NT: Bibliogr.: 34 ref.
LA: German
ER: F (Freshwater)
AB: The concentration of several trace elements was recorded weekly in 1986 and 1987 from 20 depths of lake Constance/Ueberlinger See, using atomic absorption spectrometry (AAS). Typical concentrations in mol/l were 4.4-5.3  multiplied by  10 super(-6) for strontium, 0.4-7.7  multiplied by  10 super(-7) for iron, 1.1-8  multiplied by  10 super(-8) for zinc, 3-6  multiplied by  10 super(-9) for chromium, and around 1  multiplied by  10 super(-11) for mercury. Contents of cobalt, lead, silver vanadium, and cadmium were below the detection limits of our methods. The cycling of trace elements in Lake Constance is controlled by the following mechanisms: Autochthonous precipitation of calcite decreases the epilimnetic concentration of strontium and barium, whereas variations in the concentrations of arsenic are due to biological uptake and adsorption to suspended clay. Aluminum, iron, and manganese occur mainly in particulate matter.
AN: 2692401

                                                                   1037 of 1521  
TI: Pathways and microbiology of thiosulfate transformations and sulfate reduction in a marine sediment (Kattegat, Denmark).
AU: Joergensen,-B.B.; Bak,-F.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, DK-8000 Aarhus C., Denmark
SO: APPL.-ENVIRON.-MICROBIOL. 1991. vol. 57, no. 3, pp. 847-856
LA: English
ER: M (Marine)
AB: Reductive and oxidative pathways of the sulfur cycle were studied in a marine sediment by parallel radiotracer experiments with  super(35)SO sub(4) super(2-), H sub(2) super(35)S, and  super(35)S sub(2)O sub(3) super(2-) injected into undisturbed sediment cores. The distributions of viable populations of sulfate- and thiosulfate-reducing bacteria and of thiosulfate-disproportionating bacteria were concurrently determined. Thiosulfate was concurrently oxidized to sulfate, reduced to sulfide, and disproportionated to sulfate and sulfide. There was a gradual shift from predominance of oxidation toward predominance of reduction with depth in the sediment. Disproportionation was the most important pathway overall. Thiosulfate disproportionation occurred only as cometabolism in the marine acetate-utilizing sulfate-reducing bacteria, which could not conserve energy for growth from this process alone. Oxidative and reductive cycling of sulfur thus occurred in all sediment layers with an intermediate "thiosulfate shunt" as an important mechanism regulating the electron flow.
AN: 2691391

                                                                   1038 of 1521  
TI: The influence of a changing bacterial community on trace metal scavenging in a deep-sea particle plume.
AU: Cowen,-J.P.; Li,-Yuan-Hui
AF: Dep. Oceanogr., Sch. Ocean and Earth Sci. and Technol., Univ. Hawaii at Manoa, Honolulu, HI 96822, USA
SO: J.-MAR.-RES. 1991. vol. 49, no. 3, pp. 517-542
LA: English
ER: M (Marine)
AB: An extensive set of particle samples was collected from the extended (nonbuoyant) hydrothermal plume, the distal remnant plume, and the adjacent waters in a transect across the Southern Juan de Fuca Ridge. Bacterial capsules comprised the primary species of particulate Mn. However, the data also showed significant shifts in the relative abundance of distinctive subpopulations of this bacterial community, as expressed by several consistently recurring capsule morphologies. The data are discussed with respect to distance from plume origins (relative plume age), total bacterial numbers, experimentally determined scavenging rate constants and total particulate and dissolved Mn. The geochemical cycle of Mn in an evolving hydrothermal vent plume is reflected in the distribution coefficients for Mn (K sub(D)), which increase with distance from vent origins. The potential influence that changing subpopulations of bacteria may exert on the overall scavenging behavior of Mn in this evolving natural particle population is emphasized.
AN: 2676998

                                                                   1039 of 1521  
TI: Protozoan plankton ecology.
AU: Laybourn-Parry,-J.
SO: NEW-YORK,-NY-USA-CHAPMAN-AND-HALL 1992. 231 pp
NT: Price: $99.00 (USA), $125.00 (Canada).
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: This text looks at the biology, temporal and spatial distribution patterns and the functional role of planktonic protozoa in fresh, brackish and marine waters. In recent years the importance of these organisms in ecological processes such as the flow of energy and the biogeochemical cycling of carbon, nitrogen and phosphorus in planktonic systems has become widely appreciated. While there are many books covering various planktonic biota, there is no text specifically on the planktonic protozoa. This book therefore provides aquatic biologists with a concise test on this group of organisms written by an acknowledged expert actively engaged in researching planktonic microbial processes. The chapters discuss the planktonic environment, planktonic protozoa and their ecology, important aspects of protozoan physiology, distribution and occurrence of lake protozooplankton, distribution and occurrence of marine and estuarine protozooplankton, and the functional role or protozooplankton.
AN: 2676528

                                                                   1040 of 1521  
TI: Influence of dissolved organic carbon, pH, and microbial respiration rates on mercury methylation and demethylation in lake water.
AU: Miskimmin,-B.M.; Rudd,-J.W.M.; Kelly,-C.A.
AF: Dep. Zool., Univ. Alberta, Edmonton, Alta. T6G 2E9, Canada
SO: CAN.-J.-FISH.-AQUAT.-SCI. 1992. vol. 49, no. 1, pp. 17-22
NT: Incl. bibliogr.: 27 ref.
LA: English
ER: F (Freshwater)
AB: Effects of changes in DOC concentrations, pH, and microbial respiration rates on specific rates of mercury methylation and demethylation in lake water were studied using radioisotopic techniques. Increased concentrations of DOC resulted in decreased specific rates of net methylation, possibly as a result of complexation of inorganic mercury with DOC. A reduction in pH from 7.0 to 5.0 had the greatest effect, causing to moderate increases in net methylation rate at both low and high DOC concentrations (500-2600  mu M). Rates of respiration (indicative of general rates of microbial activity), which were insensitive to pH change over the range tested (5.0-7.0), had the smallest effect on net methyl mercury production rates.
AN: 2676253

                                                                   1041 of 1521  
TI: The changing global carbon cycle: Dust to dust.
AU: Moore,-B.,III
AF: Univ. New Hampshire, Durham, NH 03824, USA
SO: MAR.-TECHNOL.-SOC.-J. 1991. vol. 25, no. 3, pp. 19-24
NT: Spec. iss.: Global Environmental Change. Part 1.
LA: English
ER: M (Marine)
AB: This paper reviews briefly the global carbon cycle and presents on introductory discussion of the role of the ocean in this cycle including comparisons with the atmosphere and the land.
AN: 2676225

                                                                   1042 of 1521  
TI: Application of a generalized scavenging model to thorium isotope and particle data at equatorial and high-latitude sites in the Pacific Ocean.
AU: Clegg,-S.M.; Bacon,-M.P.; Whitfield,-M.
AF: Sch. Environ. Sci., Univ. East Anglia, Norwich, UK
SO: J.-GEOPHYS.-RES. 1991. vol. 96, no. C11, pp. 20,655-670
LA: English
ER: M (Marine)
AB: A generalized trace metal scavenging model has been applied to particle cycle and  super(234)Th data at three equatorial Pacific sites, and to dissolved and particulate  super(228)Th,  super(230)Th, and  super(234)Th profiles at a single high-latitude station. The one-dimensional (and here steady state) model consists of two particle classes, small (suspended) and large (sinking). It is driven by particle primary production and parameterized from particle and tracer concentration and flux data. The model has been used to determine, as functions of depth, rates of particle remineralization; aggregation and disaggregation of the small and large-particle classes, respectively, and adsorption and desorption rate constants of thorium. The results are insensitive to the assumed large particle sinking rate of 150 m/d. The profiles of all three tracers at Station P are described satisfactorily by a single set of model parameters. The adsorption rate constant, normalized for the effect of particle concentration, is enhanced in the upper 100 m of the water column by a factor of 2 or greater at all sites. Values of this and the other major model parameters are consistent with earlier results for a variety of oceanic environments.
AN: 2672543

                                                                   1043 of 1521  
TI: Oxic and anoxic decomposition of tubes from the burrowing sea anemone Ceriantheopsis americanus : Implications for bulk sediment carbon and nitrogen balance.
AU: Kristensen,-E.; Aller,-R.C.; Aller,-J.Y.
AF: Inst. Biol., Odense Univ., DK-5230 Odense M, Denmark
SO: J.-MAR.-RES. 1991. vol. 49, no. 3, pp. 589-617
LA: English
ER: M (Marine)
AB: Many marine infaunal animals form organic tube and burrow linings. The infaunal sea anemone, Ceriantheopsis americanus , forms a leathery, fibrous tube lining 2-3 mm thick,  similar to 1 cm in diameter, and typically extending 20-30 cm into deposits. Tube fibers are composed of a silk-like protein copolymer, cerianthin. Tubes incubated under oxic and anoxic conditions over a period of 122 days demonstrate that initial rates of whole tube decay are 10-100 times slower than usually found for fresh planktonic debris and aquatic macrophytes despite a relatively low molar C:N ratio of  similar to 5.1. First order decomposition rate constants in oxic water, anoxic water and anoxic sediment are  similar to 0.76,  similar to 0.41 and  similar to 0.22/yr for particulate tube carbon and  similar to 0.2,  similar to 0.1 and  similar to 0.1/yr for particulate nitrogen. Tube decomposition stimulates bacterial activity in sediments from below  similar to 10 cm depth. In central Long Island Sound muds, tubes apparently account for a minimum of  similar to 0.6-1.8% and 2.8-8.4% of the steady state C and N detrital pools in the upper 10-30 cm of the sediment. C. americanus  tube production apparently accounts for  similar to 9% of the average particulate carbon and  similar to 12% of the nitrogen fluxes to the benthos.
AN: 2671523

                                                                   1044 of 1521  
TI: Nutrient cycling and the biogeochemistry of manganese, iron, and zinc in Jellyfish Lake, Palau.
AU: Landing,-W.M.; Burnett,-W.C.; Berry-Lyons,-W.; Orem,-W.H.
AF: Dep. Oceanogr., B-169, Florida State Univ., Tallahassee, FL 32306-3048, USA
SO: LIMNOL.-OCEANOGR. 1991. vol. 36, no. 3, pp. 515-525
LA: English
ER: M (Marine)
AB: The oxic waters in Jellyfish Lake, a stagnant marine lake in Palau, are depleted in NO sub(3) super(-), PO sub(4) super(3-), dissolved Si, Mn, Fe, and Zn, while the underlying anoxic waters are significantly enriched in these species and NH sub(3). NH sub(3) and PO sub(4) super(3-) regeneration and dissolved sulfide production in the anoxic zone yield a stoichiometry of C sub(138)N sub(13)P for organic matter undergoing recycling in the anoxic waters. A two-box model is used to calculate an eddy diffusion coefficient of 0.0015 cm super(2)/s across the chemocline. The upward diffusive loss of NH sub(3) added to the sedimentation rate of N and multiplied by the stoichiometric C:N ratio yields an organic carbon flux into the anoxic waters of 1,200  mu mol C/cm super(2)/yr, which is  similar to  13% of the total primary productivity.
AN: 2671461

                                                                   1045 of 1521  
TI: Geochemistry of reef interstitial waters.
AU: Tribble,-G.W.
AF: Dep. Oceanogr., Univ. Hawaii, Honolulu, HI 96822, USA
CO: 12. Annu. Albert L. Tester Memorial Symp., Hawaii, HI (USA), 2-3 Apr 1987
SO: PAC.-SCI. 1988. vol. 42, no. 1-2, pp. 135-136
NT: Summary only.
LA: English
ER: M (Marine)
AB: Water was sampled from the internal framework of a coral reef in Kaneohe Bay, Oahu. Dissolved oxygen levels were low or undetectable in the interstitial water and concentrations of dissolved methane, sulfide, and inorganic carbon were elevated. The reef interstitial water also differed from surface water in having a lower pH and higher alkalinity. Dissolved organic nitrogen and phosphorus concentrations were similar in interstitial and overlying waters, but interstitial waters were enriched with inorganic nutrients. The differences in chemical composition between reef surface water and reef interstitial water appear to result from microbial oxidation of organic matter through both oxic and anoxic pathways. Hydrological investigations indicate that the reef interstitial waters are advectively driven and that exchange with the overlying seawater occurs on a time period of several hours to a few days. The flux of nutrient-enriched water out of the reef framework may thus represent a significant source of remineralized nutrients to reef primary producers.
AN: 2670849

                                                                   1046 of 1521  
TI: High production and highstand shedding from deeply submerged carbonate banks, northern Nicaragua Rise.
AU: Glaser,-K.S.; Droxler,-A.W.
AF: Dep. Geol. and Geophys., Rice Univ., Houston, TX 77251, USA
SO: J.-SEDIMENT.-PETROL. 1991. vol. 61, no. 1, pp. 128-142
LA: English
ER: M (Marine)
AB: Because the shallow isolated carbonate banks on the northern Nicaragua Rise, the Nicaragua/Honduras and southern Jamaica carbonate shelves, and many other modern carbonate banks worldwide, are covered by an average of 20 to 30 m of water and by a thin blanket of coarse carbonate sediments, other carbonate sedimentologists have considered these banks good examples of "incipiently drowned", or even "drowned" carbonate banks. However, based on recent research on the northern Nicaragua Rise, we can demonstrate that these banks currently are healthy producers of large volumes of periplatform sediments (fine aragonite and magnesian calcite), which are exported almost entirely to the deep surrounding slopes.
AN: 2669202

                                                                   1047 of 1521  
TI: Enhanced particle fluxes in Bay of Bengal induced by injection of fresh water.
AU: Ittekkot,-V.; Nair,-R.R.; Honjo,-S.; Ramaswamy,-V.; Bartsch,-M.; Manganini,-S.; Desai,-B.N.
AF: Inst. Biogeochem. and Mar. Chem., Univ. Hamburg, Bundesst. 55, 2000 Hamburg 13, FRG
SO: NATURE. 1991. vol. 351, no. 6325, pp. 385-387
LA: English
ER: M (Marine)
AB: The melting of ice sheets during deglaciation results in the injection of large amounts of fresh water into the oceans. To investigate how such injections might influence particle fluxes in the ocean, and hence the uptake of atmospheric CO sub(2), we deployed three sediment-trap moorings (two traps in each mooring) in the northern, central and southern parts of the Bay of Bengal, respectively. From north to south, the carbonate flux increases, whereas fluxes of opal, organic carbon and particulate matter decrease. The overall flux pattern seems to be controlled by the seasonally varying input from the rivers and the accompanying shift in marine biogenic production. We conclude that freshwater pulses during deglaciation may therefore have caused similar shifts in marine biogenic production, resulting in short-term episodes of increased oceanic uptake of atmospheric CO sub(2).
AN: 2669114

                                                                   1048 of 1521  
TI: The retention of cadmium and zinc in appendicularian houses.
OT: Retention du cadmium et du zinc dans les logettes abandonnees par les appendiculaires
AU: Fisher,-N.S.; Nolan,-C.V.; Gorsky,-G.
AF: Mar. Sci. Res. Cent., State Univ. New York, Stony Brook, NY 11794-5000, USA
SO: OCEANOL.-ACTA. 1991. vol. 14, no. 4, pp. 427-430
LA: English
ER: M (Marine)
AB: The discarded houses of appendicularians can be important components of marine snow and might therefore be instrumental in mediating the vertical flux of metals from surface waters in oceanic ecosystems. Their significance in this regard depends on the retention of metals in these organic debris. To assess this, an experiment was conducted in which the release of cadmium and zinc from discarded houses of the appendicularian Oikopleura longicauda  was studied using gamma-emitting radiotracers. The retention curves of the two metals conformed with a single exponential decay loss model. The retention half-times were of the order of two days, suggesting that sinking appendicularian houses would not transport these metals to deep ocean waters but could contribute to their flux out of surface waters.
AN: 2665944

                                                                   1049 of 1521  
TI: Composition and fate of organic matter in submarine cave sediments; Implications for the biogeochemical cycle of organic carbon.
OT: Composition et devenir de la matiere organique sedimentaire dans une grotte sous-marine; consequences sur le cycle biogeochimique du carbone organique
AU: Fichez,-B.
AF: Cent. Oceanol. Marseille, Stn. Mar. Endoume, 13007 Marseille, France
SO: OCEANOL.-ACTA. 1991. vol. 14, no. 4, pp. 369-377
LA: English
ER: M (Marine)
AB: The biochemical composition of the sediments in a Mediteranean submarine cave (Marseille, France) was studied, and a budget for the biogeochemical cycle of organic carbon was calculated. Chloropigment and lipid levels were markedly lower in sediments from the dark inner section of the cave compared to the twilight outer section. These decreased levels were related to the decrease in the vertical inputs of particulate organic matter. Lower decreases were recorded in the sediment content of other organic constituents (organic carbon, organic nitrogen, carbohydrates, proteins). The anlaysis of carbohydrate and protein extracted from sediments (NaOH 1 N, 24 h, 4 degree C) yielded no significant information, demonstrating the ambiguous significance of such a chemical approach in sediments low in organic matter.
AN: 2664108

                                                                   1050 of 1521  
TI: Rare earth elements in the Mediterranean Sea and mixing in the Mediterranean outflow.
AU: Greaves,-M.J.; Rudnicki,-M.; Elderfield,-H.
AF: Dep. Earth Sci., Univ. Cambridge, Downing St., Cambridge CB2 3EQ, UK
SO: EARTH-PLANET.-SCI.-LETT. 1991. vol. 103, no. 1-4, pp. 169-181
LA: English
ER: M (Marine)
AB: Mediterranean surface waters contain elevated levels of the rare earth elements compared to similar nutrient-depleted open ocean waters. Application of a flux balance model shows that the Mediterranean is a net sink for Ce and a net source for the other REE. The abundance pattern of the excess REE required for mass balance is enriched in heavy REE and has a negative Ce anomaly. This supports a marine, possibly coastal, source for the REE. Although the magnitudes of the fluxes involved are consistent with aeolian input, an aeolian source would require large-scale removal of Ce and the light REE within the Mediterranean Sea. A mixing model to compute trace metal anomalies in the Mediterranean outflow predicts the observed REE concentrations well. This implies that Ce behaves conservatively in outflow waters over the calculated one-month period for Mediterranean water to reach the study site. Application to other trace metals gives good agreement for Al, Cd and Mn.
AN: 2661317

                                                                   1051 of 1521  
TI: Oceanic delta-13-carbon values as indicators of atmospheric oxygen depletion.
AU: Hoffman,-A.; Gruszczynski,-M.; Malkowski,-K.
AF: Inst. Paleobiol., Pol. Acad. Sci., Al. Zwirki Wigury 93, PL-02-089 Warszaw, Poland
SO: MOD.-GEOL. 1990. vol. 14, no. 3, pp. 211-221
LA: English
ER: M (Marine)
AB: Theoretical analysis of the environmental meaning and consequences of very large drops in the carbon isotopic composition of seawater demonstrates they indicate that the exosystem has developed a potential for becoming a substantial sink for oxygen. When a drop in the oceanic carbon-13-delta value is of a magnitude comparable to those recorded close to the Precambrian-Cambrian and Permian-Triassic transitions, it indicates a global-scale preponderance of organic carbon oxidation over its deposition in the ocean. Two alternative scenarios of such a process can be envisaged. The onset of deep-water circulation may bring oxygen down to the bottom of the previously stagnant and stratified ocean ("overfed-to-hungry-ocean switch" scenario). Atmospheric oxygen then sinks in the ocean, where it oxidizes the reduced chemical species that accumulated earlier at the seabottom. Alternatively, oxidation of organic carbon may occur via bacterial sulfate-to-sulfide reduction in the anoxic, lower box of stagnant and stratified ocean ("sulfate-reduction" scenario).
AN: 2658679

                                                                   1052 of 1521  
TI: The seasonal behaviour of carbon dioxide and oxygen in the coastal North Sea along the Netherlands.
AU: Hoppema,-J.M.J.
AF: Netherlands Inst. Sea Res., P.O. Box 59, 1790 AB Den Burg, Texel, Netherlands
SO: NETH.-J.-SEA-RES. 1991. vol. 28, no. 3, pp. 167-179
LA: English
ER: M (Marine)
AB: Total CO sub(2) (TCO sub(2)) distribution patterns in the coastal North Sea in different seasons showed decreasing values towards the open sea. The higher values near the coast were caused by TCO sub(2) outflow from the Rhine/Meuse. The highest values were observed in Nov, irrespective of the salinity. Mixing generally resulted in linear relationships between TCO sub(2) and salinity, but scattering was lowest in Nov. Both pH (measured) and pCO sub(2) (calculated) clearly demonstrated the influence of biological activity on the CO sub(2) system. In Nov, pCO sub(2) was very high near the coast (> 450  mu atm). This is attributed mainly to mixing, and only partly to mineralization. The oxygen distributions were consistent with those of the CO sub(2)-related parameters, the deviations being opposite. The data showed that, in accordance with theory, the equilibration of O sub(2) with the atmosphere was faster than for CO sub(2). TCO sub(2)- alkalinity diagrams were only of limited value, since normalization to constant salinity was hampered by freshwater variations of TCO sub(2) combined with the variability of the residence time of the water masses in the coastal area.
AN: 2658655

                                                                   1053 of 1521  
TI: New life discovered in Lake Baikal. A community based on bacterial chemosynthesis.
OT: Novoe v prirode-Bajkala, soobshchestvo, osnovannoe na bakterial'nom khemosinteze
AU: Kuznetsov,-A.P.; Strizhov,-V.P.; Kuzin,-V.S.; Fialkov,-V.A.; Yastrebov,-V.S.
AF: IOAN, Moscow, Russia
SO: IZV.-AN-S.S.S.R.-BIOL.. 1991. no. 5, pp. 766-772
LA: Russian
ER: F (Freshwater)
AB: The authors describe a bottom community hitherto unknown to science and first discovered in the summer of 1990. The community is an extraordinarily dense settlement of sponges, amphipods, planarians, fishes, other animals and vast mat-like bacterial bottom covers. In its structure and function the community is analogous to oceanic bottom communities found at cold or slightly heated sulfide-methane seeps and hydrated gas vents in plate subduction regions. There is evidence that the metabolism of the community is based on methane (CH sub(4)) of biogenic genesis intensively implicated in biochemosynthesis produced in the community by methanotrophic bacteria.
AN: 2657828

                                                                   1054 of 1521  
TI: Composition and bacterial utilization of photosynthetically produced organic matter in an eutrophic lake.
AU: Siuda,-W.; Wcislo,-R.; Chrost,-R.J.
AF: Dep. Environ. Microbiol., Inst. Microbiol., Univ. Warsaw, ul. Karowa 18, 00-325 Warsaw, Poland
SO: ARCH.-HYDROBIOL. 1991. vol. 121, no. 4, pp. 473-484
NT: Bibliogr.: 27 ref.
LA: English
ER: F (Freshwater)
AB: Photosynthetic production, composition and utilization of organic matter were studied in the pelagic zone of highly eutrophic Lake Mikolajskie (Mazurian Lake District, Poland). About 97% of total fixed  super(14)C-CO sub(2) was photosynthetically incorporated into algal cells, and about 3% of  super(14)C was fixed by microplankton in the darkness. Twelve percent of photosynthetically produced organic carbon (PhOC) was released by phytoplankton into the water, 8% of PhOC was respired, and about 80% of  super(14)C-PhOC remained in algal cells. Chemical composition of PhOC strongly depended upon light conditions.  super(14)C was predominantly incorporated into the two-molecular-weight compounds (LMWC) and polysaccharides. Proteins and lipids were produced in smaller quantities, however, their production significantly increased at low light intensity.
AN: 2655424

                                                                   1055 of 1521  
TI: Decomposition of Rhizophora mangle, Avicennia schaueriana  and Laguncularia racemosa  leaves in a mangrove of Paranagua Bay (southeastern Brazil).
AU: Sessegolo,-G.C.; Lana,-P.C.
AF: Cent. Biol. Mar., Univ. Fed. Parana, 83200 Pontal do Sul, Parana, Brazil
SO: BOT.-MAR. 1991. vol. 34, no. 4, pp. 285-289
LA: English
ER: M (Marine)
AB: The decomposition of senescent leaves of the mangrove species Rhizophora mangle  L., Avicennia schaueriana  Stapf et Leechman and Laguncularia racemosa  Gaertn. was investigated at Baguacu tidal creek (Paranagua Bay, SE Brazil), under subtidal, intertidal and supratidal conditions. Overall decomposition rates were evaluated by weight loss over time in litter bags. Half-life for decomposition varied between 10.5 days for Avicennia  leaves permanently immersed in the water column and 249 days for Rhizophora  leaves under supratidal conditions. Instantaneous decomposition constants (k), that ranged from -0.003 (Rhizophora , supratidal) to -0.043 (Avecennia , immersed), were consistently higher with decreasing elevation of site location, indicating that submersion frequency is important in determining the rate of plant breakdown.
AN: 2654529

                                                                   1056 of 1521  
TI: Major role of the cyanobacterium Trichodesmium  in nutrient cycling in the North Atlantic Ocean.
AU: Carpenter,-E.J.; Romans,-K.
AF: Mar. Sci. Res. Cent., State Univ. New York, Stony Brook, NY 11794-5000, USA
SO: SCIENCE-WASH.. 1991. vol. 254, no. 5036, pp. 1356-1358
LA: English
ER: M (Marine)
AB: The diazotrophic cyanobacterium Trichodesmium  is a large  similar to 0.5 by 3 millimeters) phytoplankter that is common in tropical open-ocean waters. Measurements of abundance, plus a review of earlier observations, indicate that it, rather than the picophytoplankton, is the most important primary producer (about 165 milligrams of carbon per square meter per day) in the tropical North Atlantic Ocean. Inclusion of this organism, plus the abundant diazotrophic endosymbiont Richelia intracellularis  that is present in some large diatoms, in biogeochemical studies of carbon and nitrogen may help explain the disparity between various methods of measuring productivity in the oligotrophic ocean. Carbon and nitrogen fixation by these large phytoplankters also introduces a new paradigm in the biogeochemistry of these elements in the sea.
AN: 2653224

                                                                   1057 of 1521  
TI: Scientifically based strategies for marine environmental protection and management.
AU: Gray,-J.S.; Calamari,-D.; Duce,-R.; Portmann,-J.E.; Wells,-P.G.; Windom,-H.L.
AF: Dep. Mar. Zool., Univ. Oslo, P.O. Box 1064, 0316 Blindern, Oslo 3, Norway
SO: MAR.-POLLUT.-BULL. 1991. vol. 22, no. 9, pp. 432-440
LA: English
ER: M (Marine)
AB: During the last decades, mankind has faced a wide range of environmental degradations: changes in climatic conditions and biogeochemical cycles, a number of ecoaccidents, the appearance of xenobiotics in remote areas and a general world-wide deterioration in environmental quality. The results in the aquatic environment were dramatic with effects such as massive fish kills and large areas of sea bed devoid of oxygen. Measures taken to protect the aquatic environment from such effects thus far have been based on strategies such as the Water Quality Standards, Black and Grey Lists and the Precautionary Principle.
AN: 2652863

                                                                   1058 of 1521  
TI: Ocean's role in the global carbon cycle. Foreign trip report, June 1, 1990-December 20, 1990.
AU: Joos,-L.F.
CA: Oak Ridge Natl. Lab., TN (USA)
SO: 1990. 17 pp
NT: NTIS Order No.: DE91005985/GAR.
RN: ORNL/FTR-3847 (ORNLFTR3847)
LA: English
ER: M (Marine)
AB: The traveler collaborated with Dr. J.L. Sarmiento of the Program in Atmospheric Sciences, Princeton University, and Dr. U. Siegenthaler of the University of Bern in box-model studies of the potential enhancement of oceanic CO sub(2) uptake by fertilizing the southern ocean with iron. As a result of this collaboration, a letter describing the results was submitted to the journal Nature. Sensitivity studies were carried out to gain a better understanding of the processes involved for a hypothetical iron fertilization of the ocean. (Contract AC05-84OR21400. Sponsored by Department of Energy, Washington, DC.)
AN: 2652543

                                                                   1059 of 1521  
TI: Aerobic and anaerobic mineralization of organic material in marine sediment microcosms.
AU: Hansen,-L.S.; Blackburn,-T.H.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, DK-8000 Aarhus C, Denmark
SO: MAR.-ECOL.-PROG.-SER. 1991. vol. 75, no. 2-3, pp. 283-291
NT: Bibliogr.: 40 ref.
LA: English
ER: M (Marine)
AB: Fluxes of total CO sub(2), O sub(2), NO sub(3) super(-)+NO sub(2) super(-), DON (dissolved organic nitrogen) and HS super(-) were measured across the interface of a coastal bay sediment for 43 d. The seawater overlying the defaunated sediment cores was changed continuously. Two treatments were employed: oxygenated overlying water (OX-cores) and anoxic water (AN-cores). Fluxes were measured before and after addition of an organic substrate, and loss of POM (particulate organic matter) was measured at the end of the experiment. Loss of POC (particulate organic carbon) from the sediment was the same under aerobic and anaerobic conditions. However, the highest efflux of CO sub(2) was measured in the OX-cores, and the highest efflux of DOC occurred in the AN-cores before and after addition of fresh substrate. Similarly, loss of PON (particulate organic nitrogen) from the sediment was the same in the 2 treatments, but the highest fluxes of NH sub(4) super(+) and DON were measured in the AN-cores.
AN: 2651403

                                                                   1060 of 1521  
TI: Sediment phosphorus loading beneath dense canopies of aquatic macrophytes.
AU: Frodge,-J.D.; Thomas,-G.L.; Pauley,-G.B.
AF: Washington Coop. Fish. and Wildl. Res. Unit, WH-10, Univ. Washington, Seattle, WA 98195, USA
SO: LAKE-RESERVOIR-MANAGE. 1991. vol. 7, no. 1, pp. 61-71
LA: English
ER: F (Freshwater)
AB: Dense surface canopies of aquatic macrophytes were associated with significant changes in the physical and chemical water quality of two shallow Pacific Northwest lakes. Internal loading of phosphorus (P) was observed at the sediment-water interface beneath canopies of Ceratophyllum demersum  L. and Myriophyllum exalbescens  (Fern.) Jeps. and in deep open-water areas when dissolved oxygen (DO) concentrations were  less than or equal to  0.4 mg/L. Aerobic release of P was observed at sites with surface covers of the green filamentous algae Pithophora  sp. where concentrations of DO were > 20 mg/L and pH > 9. An increase in surface P concentrations was also observed in sites dominated by the floating leafed Brasenia schreberi  Gmel., and appeared to be associated with leaf decay within the surface canopy. There was an apparent net loss of phosphorus to the sediments beneath both submergent and floating leafed canopies when DO concentrations were  greater than or equal to  0.4 mg/L. The removal or reduction of the plant canopies could simultaneously reduce anoxic P release, while increasing aerobic P release. These P cycling mechanisms should be considered in the management of aquatic macrophytes.
AN: 2650918

                                                                   1061 of 1521  
TI: The processing of elements by mires in agricultural landscape: Mass balances based on sub-surface hydrology.
AU: Kruk,-M.
AF: Dep. Plant Ecol., Inst. Ecol., Pol. Acad. Sci., Dziekanow Lesny (near Warsaw), 05-092 Lomianki, Poland
SO: EKOL.-POL. 1990. vol. 38, no. 1, pp. 73-117
NT: Published 1991.
LA: English
ER: F (Freshwater)
AB: Small mires located in hollows with no surface outflows were subject to biogeochemical studies by input-output balance method based on measurements of groundwater flows. Estimates were made of water balance as well as balance of dissolved forms of: N (including N-NO sub(3), N-NH sub(4), N sub(org)), K, Na, Ca, Mg, S-SO sub(4) and Cl. The following undrained mires were examined: two with minerotrophic fen and one with ombrotrophic-transition bog. Also a drained minerotrophic mire was studied. It was observed that nitrogen outflow from undrained mires was considerably smaller. The mire with ombrotrophic-transition bog could retain a substantial part of a scanty inflow of the examined elements, while mires with minerotrophic fen - upmost a tiny part of a rich inflow mainly from catchment basin. Drained minerotrophic mire was no longer apt to retain a majority of elements, nitrogen in particular.
AN: 2650777

                                                                   1062 of 1521  
TI: A sea of change: Monitoring the oceans' carbon cycle.
AU: Karl,-D.M.; Winn,-C.D.
SO: ENVIRON.-SCI.-TECHNOL. 1991. vol. 25, no. 12, pp. 1976-1981
LA: English
ER: M (Marine)
AN: 2650736

                                                                   1063 of 1521  
TI: Dissimilatory Fe(III) and Mn(IV) reduction.
AU: Lovley,-D.R.
AF: Water Resour. Div., U.S. Geol. Surv., 430 Natl. Cent., Reston, VA 22092, USA
SO: MICROBIOL.-REV. 1991. vol. 55, no. 2, pp. 259-287
LA: English
ER: F (Freshwater)
AB: The oxidation of organic matter coupled to the reduction of Fe(III) or Mn(IV) is one of the most important biogeochemical reactions in aquatic sediments, soils, and groundwater. This process plays an important role in the oxidation of natural and contaminant organic compounds in a variety of environments and contributes to other phenomena of widespread significance such as the release of metals and nutrients into water supplies, the magnetization of sediments, and the corrosion of metal. Until recently, much of the Fe(III) and Mn(IV) reduction in sedimentary environments was considered to be the result of nonenzymatic processes. However, microorganisms which can effectively couple the oxidation of organic compounds to the reduction of Fe(III) or Mn(IV) have recently been discovered. With Fe(III) or Mn(IV) as the sole electron acceptor, these organisms can completely oxidize fatty acids, hydrogen, or a variety of monoaromatic compounds. The available evidence indicates that this enzymatic reduction of Fe(III) or Mn(IV) accounts for most of the oxidation of organic matter coupled to reduction of Fe(III) and Mn(IV) in sedimentary environments. Little is known about the diversity and ecology of the microorganisms responsible for Fe(III) and Mn(IV) reduction, and only preliminary studies have been conducted on the physiology and biochemistry of this process.
AN: 2650048

                                                                   1064 of 1521  
TI: Microbial activity in the sediments of a eutrophic lagoon.
OT: Il ruolo dell'attivita microbica dei sedimenti nelle distrofie degli ambienti acquatici
AU: Izzo,-G.
AF: ENEA-Casaccia, C.P. 2400, 00100 Rome, Italy
CA: Gruppo Biologia Marina S.S.S.P., Torino (Italy)
CO: 19. Congr. della Societa Italiana di Biologia Marina, Naples (Italy), 24-28 Sep 1987
SO: OEBALIA. pp. 441-451
NT: 15-1, N.S.
LA: Italian
ER: B (Brackish)
AB: Th sulfate-reducing activity of a eutrophic lagoon (Orbetello, Tuscany, Italy) was measured in the sediments at two-week intervals for a period of 7 months. The summer increase of this activity seems to be responsible for anoxic crises of the water column induced by the chemical oxidation of the produced sulphides. The daily cycle of the dissolved oxygen in the water column shows a strong night consumption. The redox profiles in sediments which are considered indicators of microbial activity seem to be influenced by internal water circulation. A water flow was induced artificially to prevent anoxic phenomena.
AN: 2649171

                                                                   1065 of 1521  
TI: A link between biologically imported particulate organic nutrients and the detritus food web in reef communities.
AU: Rothans,-T.C.; Miller,-A.C.
AF: Dep. Biol., California State Univ., Long Beach, CA 90840-3702, USA
SO: MAR.-BIOL. 1991. vol. 110, no. 1, pp. 145-150
NT: Bibliogr.: 30 ref.
LA: English
ER: M (Marine)
AB: Previous work with planktivorous fishes has shown that they import particulate organic and inorganic material to reefs in the form of fecal pellets, which, in part, are deposited in crevices on the reef where these fishes shelter during their inactive period. We examined the attractiveness of fish feces to potential reef detritivores by placing traps baited with planktivorous fish feces, along with unbaited control traps, in crevices on rocky reefs at Santa Catalina Island, California, USA, between June 1982 and November 1983, and on coral reefs at St. Croix, U.S. Virgin Islands, during June 1983. Significantly more animals (the majority being crustaceans) were trapped in the baited traps compared to the unbaited controls on both reefs. There was also a significant association between the presence of trapped animals and fish feces at Santa Catalina Island (p = 0.009).
AN: 2646163

                                                                   1066 of 1521  
TI: Oceanic phytoplankton communities: Our changing perception.
AU: Glover,-H.E.
AF: Box 165, Lakeside Dr., Boothbay, ME 04537, USA
SO: REV.-AQUAT.-SCI. 1991. vol. 5, no. 3-4, pp. 307-331
LA: English
ER: M (Marine)
AB: Ocean systems were traditionally thought to be static aqueous deserts of low productivity with a low "steady-state" diffusional supply of nitrate across the thermocline. Over the last decade, this view has been increasingly challenged due to several factors: the adoption of new methodologies, increased sampling frequency, and the discovery of a diverse picophytoplankton (< 2  mu m) that provides most of the primary production. Our current view of oceanic nutrient supply recognizes the importance of episodic events that increase the nitrate flux to surface waters and rapidly enhance photosynthetic rates. Recent estimates of oceanic primary production and that portion supported by nitrate have been revised upwards, which has a direct impact upon calculations of global carbon fluxes. We now believe that there is a rapid cycling of carbon and nitrogen in the open sea that is driven by synergistic picoplankton interactions between photoautotrophs, chemoautotrophs, methanotrophs, heterotrophic bacteria, and their protozooplankton grazers in the water column and on microaggregates.
AN: 2640934

                                                                   1067 of 1521  
TI: Production and consumption of dimethyl-sulfoniopropionate in marine microbial mats.
AU: Visscher,-P.T.; Gemerden,-H.-van
AF: Div. Mar. and Atmos. Chem., Rosenstiel Sch. Mar. and Atmos. Sci., 4600 Rickenbacker Causeway, Miami, FL 33149-1098, USA
SO: APPL.-ENVIRON.-MICROBIOL. 1991. vol. 57, no. 11, pp. 3237-3242
LA: English
AB: The fate of dimethyl-sulfoniopropionate (DMSP), a major sulfonium compound in marine ecosystems, was examined in Microcoleus chthonoplastes -dominated microbial mats. Chemical decomposition of DMSP was observed under laboratory conditions at pH values higher than 10.0. pH profiles measured in situ showed that these highly alkaline conditions occurred in microbial mats. Axenic cultures of M. chthonoplastes  contained 37.3  mu mol of DMSP g of protein super(-1), which was partially liberated when the cells were subjected to an osmotic shock. DMSP-amended mat slurries showed a rapid turnover of this compound. The addition of glutaraldehyde blocked DMSP decrease, indicating biological consumption. Populations of potential dimethyl sulfide consumers were found in the top 10 mm of the mat.
AN: 2640925

                                                                   1068 of 1521  
TI: A model system derived from marine diatoms for investigating the activity of particle-associated bacteria.
AU: Griffith,-P.C.; Fletcher,-M.
AF: Cent. Mar. Biotech., Univ. Maryland, 600 E. Lombard St., Baltimore, MD 21202, USA
SO: J.-MICROBIOL.-METHODS. 1990. vol. 12, no. 2, pp. 65-74
LA: English
ER: M (Marine)
AB: A model system for examining bacterial attachment to and degradation of marine particulate matter is described. The model particles consisted of a hydrophilic matrix derived from marine diatoms, contained primarily Si, Ca and Al oxides, and had high surface area relative to weight. A marine Pseudomonas  sp. (NCMB 2021) attached readily to the particles. Biomass of free and particle-associated bacteria was quantified using direct counts, radiolabeling, and protein determination. Bacterial activity was assayed by measuring the hydrolysis of L-leucine-methylcumarinylamide, a fluorescently labeled substratum, that served as an analog to protein macromolecules. The cell-specific rate of substratum hydrolysis by attached bacteria was half that of free-living bacteria.
AN: 2636287

                                                                   1069 of 1521  
TI: Effect of growth and subsequent decomposition of blue-green algae on the transformation of iron and manganese in submerged soils.
AU: Das,-S.C.; Mandal,-B.; Mandal,-L.N.
AF: Micronutr. Res. Lab., Dep. Agric. Chem. and Soil Sci., Bidhan Chandra Krishi Viswavidyalaya, Kalyani 741235, West Bengal, India
SO: PLANT-SOIL. 1991. vol. 138, no. 1, pp. 75-84
LA: English
ER: F (Freshwater)
AB: N sub(2)-fixing blue-green algae (Cyanobacteria), besides enriching soils with N and organic carbon, may modify chemical and electro-chemical properties of the soils resulting in a change in availability of some micronutrient elements. An experiment was conducted to study the effects of growth and subsequent decomposition of blue-green algae on changes in the different forms of Fe and Mn in four soils under submerged condition. A mixed algal culture containing Anabaena, Nostoc, Cylindrospermum), and Tolypothrix  was used as inoculum. It was allowed to grow for 2 months, after which the soils were extracted. Growth of blue-green algae in submerged rice soils caused a decrease in the NH sub(4) OAc-extractable forms of Fe and MN with concomitant increases in all the other four determined forms of the elements. Such decreases and/or increases in different forms of Fe and Mn in soils were explained as being due to release of O sub(2), addition of organic matter and liberation of extracellular organic compounds by the blue-green algae during their growth.
AN: 2636174

                                                                   1070 of 1521  
TI: On the interrelationship between temporal trends in  delta  super(13)C,  delta  super(18)O, and  delta  super(34)S in the World Ocean.
AU: Hoffman,-A.; Gruszczynski,-M.; Malkowski,-K.
AF: Inst. Paleobiol., Pol. Acad. Sci., Al. Zwirki i Wigury 93, PL-02-089 Warszawa, Poland
SO: J.-GEOL. 1991. vol. 99, no. 3, pp. 355-370
LA: English
ER: M (Marine)
AB: The phenomena of (i) inverse correlation between the oceanic carbon and sulfur isotopic curves, and (ii) covariation between the oceanic carbon and oxygen isotopic curves at all their major excursions appear as paradoxes in the current paradigm of global biogeochemical cycles. These phenomena, however, are fully explicable by our model proposing that the ocean alternates between two general modes: stagnant, stratified, and net autotrophic (overfed) ocean, and vigorously mixed and net heterotrophic (hungry) ocean. The model has far-reaching implications for (i) the causal explanation of both secular trends and major shifts in the oceanic isotopic curves, and (ii) for the application of oxygen isotopic data for paleotemperature and paleoenvironment determinations.
AN: 2633775

                                                                   1071 of 1521  
TI: The transport of CO sub(2) into Arctic and Antarctic Seas: Similarities and differences in the driving processes.
AU: Anderson,-L.G.; Jones,-E.P.
AF: Dep. Anal. and Mar. Chem., Univ. Goteborg, S-412 96 Goteborg, Sweden
SO: J.-MAR.-SYST. 1991. vol. 2, no. 1-2, pp. 81-95
LA: English
ER: M (Marine)
AB: In polar regions, the partial pressure of CO sub(2) in the ocean is decreased mainly by two processes, a decrease in temperature and biological productivity. In the Arctic, the vertical transport of cooled surface water by deep convection mainly takes place in the Greenland Sea and penetrates to a very large depth, while in the Antarctic the deep convection does not reach the same depths, at least not as frequently. Biological production is significant for the vertical transport of carbon in both the Arctic and Antarctic; however, in the Arctic the production is mainly over the large shelves, while in the Antarctic it takes place mostly over the deep ocean. Total alkalinity, total carbonate, calcium, oxygen, salinity and temperature data from several expeditions in the Arctic and the SWEDARP 88/89 expedition in the Antarctic are used in this discussion.
AN: 2633567

                                                                   1072 of 1521  
TI: Geochemistry and paleoceanographic setting of central Nevada bedded barites.
AU: Jewell,-P.W.; Stallard,-R.F.
AF: Dep. Geol. and Geophys. Sci., Princeton Univ., Princeton, NJ 08544, USA
SO: J.-GEOL. 1991. vol. 99, no. 2, pp. 151-170
LA: English
ER: M (Marine)
AB: The bedded barite deposits of central Nevada are hosted by rocks of the Roberts Mountains allochthon and constitute the largest barite reserves in North America. Detailed geochemical studies of three barite deposits in the Devonian Slaven Chert indicate that rocks surrounding the barite have elevated concentrations of carbon and phosphorus relative to nonbarite-bearing rocks. Rare earth element data suggest that the barites were deposited in oxygenated seawater far from a spreading center. The assembled data suggest a biogenic rather than a hydrothermal origin for the barite deposits. A model is proposed in which the barites were deposited at the O sub(2)-H sub(2)S transition of a coastal upwelling system in the Late Devonian ocean.
AN: 2633234

                                                                   1073 of 1521  
TI: Some aspects of the nitrogen cycle in a Californian strand ecosystem.
AU: Holton,-B.,Jr.; Barbour,-M.G.; Martens,-S.N.
AF: Dep. Bot., Univ. California, Davis, CA 95616-8537, USA
SO: MADRONO. 1991. vol. 38, no. 3, pp. 170-184
LA: English
ER: M (Marine)
AB: Nitrogen inputs and storage pools were quantified for 20 months on a perennial grass dominated beach-foredune area at Pt. Reyes National Seashore, CA. Atmospheric input of ammonium and nitrate by bulk precipitation (rain + dry fallout) was 1.6 kg N/ha/yr and by summer fog condensation was 4.2 kg N/ha/yr. Non-symbiotic nitrogen fixation was not detected and fixation by a nodulated legume species is negligible relative to atmospheric inputs. The total ecosystem nitrogen pool was only 390 kg/ha, 78% of which was soil organic nitrogen, 18% was in vegetation, and 4% was inorganic soil nitrogen. Living vascular plant tissue contained 1.7% nitrogen - a value typical of crop plants on fertile soil - despite soil nitrogen content < 0.006%.
AN: 2631604

                                                                   1074 of 1521  
TI: Phosphorus solubilizing yeasts in estuarine environment.
AU: Naik,-M.V.; D'-souza,-J.; Araujo,-A.
AF: Cent. Postgrad. Instruct. and Res., Univ. Bombay, Panaji, Goa 403 001, India
SO: INDIAN-J.-MAR.-SCI. 1982. vol. 11, no. 2, pp. 197-198
LA: English
ER: B (Brackish)
AB: Estuarine yeasts (42) were qualitatively screened for phosphorus solubilizing ability and 23 isolated were later quantitatively tested in Czapek-Dox medium containing tricalcium phosphate as phosphorus source. P-solubilizing activity was maximum in pH range 6-6.5 and an incubation period of 6 days was required for an appreciable quantity of phosphorus to be leached into the medium. The maximum amount of phosphorus was solubilized by Torulopsis glabrata  (61.3%) followed by Kloeckera apiculata  (46%) and Hansenula anomala  (43%).
AN: 2631504

                                                                   1075 of 1521  
TI: Laboratory investigations into the effect of marine organic material on the sea-salt aerosol generated by bubble bursting.
AU: Cloke,-J.; McKay,-W.A.; Liss,-P.S.
AF: Sch. Environ. Sci., Univ. East Anglia, Norwich NR4 7TJ, UK
SO: MAR.-CHEM. 1991. vol. 34, no. 1-2, pp. 77-95
LA: English
ER: M (Marine)
AB: A simple aerosol generation rig has been used to investigate the effect of marine organic material on the flux and inorganic particulate enrichment of marine aerosol. Aerosol was generated in the laboratory from UK coastal seawater samples collected on the monthly basis for 1 year. Initial aerosol generation rates showed no significant seasonal trend, whereas the total amount of aerosol generated before the rate fell to the baseline reached a plateau at around 60 ml from March to October, a factor of six greater than earlier in the year. Dissolved organic carbon (DOC) and surfactant activity have been measured in seawater. The measurements show evidence of seasonal cycles for both determinants. Surfactant activity shows a broad peak in the late autumn. Peak DOC concentrations were seen in early summer. The surfactant-to-DOC ratio varies seasonally. Particulate organic carbon (POC) is highly variable, the ratio of POC to particulate loading being more useful. Peak values may indicate biological production.
AN: 2630706

                                                                   1076 of 1521  
TI: Leaf litter decomposition in three Louisiana freshwater forested wetland areas with different flooding regimes.
AU: Conner,-W.H.; Day,-J.W.,Jr.
AF: Baruch Forest Sci. Inst., Box 596, Georgetown, SC 29442, USA
SO: WETLANDS. 1991. vol. 11, no. 2, pp. 303-312
LA: English
ER: F (Freshwater)
AB: Litter decomposition was studied for one year in three Louisiana forested wetland sites with different flooding regimes. Decomposition was significantly higher in a crayfish pond where flooding was manipulated by pumping. Only 20% of the original dry mass remained after 46 weeks versus over 40% in the natural and impounded wetland forests. Nitrogen was immobilized in the natural and impounded areas but was mineralized during the spring and summer in the managed area. Phosphorus was not immobilized in the natural and impounded areas like nitrogen but was mineralized much more slowly in these areas than it was in the managed area. Because of the slower decomposition in the natural and impounded areas, falling leaf litter buries the old, partially decomposed material. Thus, there tends to be a net accumulation of organic matter, nitrogen, and phosphorus in stagnant, more flooded areas and mineralization and/or export from free-flowing areas.
AN: 2630652

                                                                   1077 of 1521  
TI: (Phosphorus in aquatic sediments: Geochemical forms and identification methods).
OT: Le phosphore dans les sediments aquatiques: Formes geochimiques et methodes d'identification
AU: Andrieux,-F.
AF: IFREMER, Cent. Brest, Dep. Environ. Littoral, B.P. 70, 29280 Plouzane, France
SO: PLOUZANE,-FRANCE-IFREMER,-CENTRE-DE-BREST 1991. no. 91.12, 71 pp
NT: IFREMER Brest DRO-EL/91.12.
LA: French
ER: M (Marine)
AB: The geochemical forms of phosphorus in particulate matter and sediments are described along with the global and specific methods used for their determination. Then, the concentrations found by several authors in different sediments are reviewed. Finally, works on the bioavailability of phosphorus from sediments are described and they indicate the difficulty of its evaluation for the different forms encountered.
AN: 2629723

                                                                   1078 of 1521  
TI: Our changing planet: The FY 1992 U.S. Global Change Research Program. A report by the Committee on Earth and Environmental Sciences. A supplement to the U.S. President's fiscal year 1992 budget.
CA: Federal Coord. Counc. for Science, Engineering and Technology, Washington, DC (USA)
SO: 1991. 102 pp
NT: NTIS Order No.: PB91-145805/GAR.
LA: English
AB: The USGCRP was developed in response to the evolving nature of Earth science research to a more multidisciplinary or Earth System Science approach. The foundation of Earth System Science is the belief that sound scientific information on global change must be derived from a comprehensive, integrated view of the interactions among key components of the Earth system, and the influence of human activities on them. The four FY 1992 Integrating Themes are: Climate Modeling and Prediction: Global Water and Energy Cycles; Global Carbon Cycle; and Ecological Systems and Population Dynamics.
AN: 2627088

                                                                   1079 of 1521  
TI: Modeling pCO sub(2) in the upper ocean. A review of relevant physical, chemical, and biological processes.
AU: Archer,-D.
CA: Washington Univ., Seattle (USA). Dep. of Oceanography
SO: REP.-U.S.-DEP.-ENERGY. 1990. 69 pp
NT: NTIS Order No.: DE91004696/GAR.
RN: DOE/RL/01830-H5T (DOERL01830H5T)
LA: English
ER: M (Marine)
AB: This report summarizes our current understanding of the physical, chemical, and biological processes that control the natural cycling of carbon dioxide (CO(sub 2)) in the surface ocean. Three families of mixed layer models have been developed. This paper explores behavioral distinctions between the three types of models, and summarizes previously published comparisons of the generality, accuracy, and computational requirements of the three models. The application of mixed layer models to treatment of sea ice is also reviewed. (Contract AC06-76RL01830. Sponsored by Department of Energy, Washington, DC.)
AN: 2625081

                                                                   1080 of 1521  
TI: Direct measurement of dissolved inorganic nitrogen exchange and denitrification in individual polychaete (Nereis virens ) burrows.
AU: Kristensen,-E.; Jensen,-M.H.; Aller,-R.C.
AF: Inst. Biol., Odense Univ., DK-5230 Odense M, Denmark
SO: J.-MAR.-RES. 1991. vol. 49, no. 2, pp. 355-377
LA: English
ER: M (Marine)
AB: The burrows of macroinfauna are significant sites of sediment-water nitrogen exchange and associated microbial activity. In this study, the exchange of dissolved inorganic nitrogen (DIN) and nitrogen cycle reaction rates were quantified in individual burrows of the estuarine polychaete Nereis virens . Burrow ventilation rate and DIN (NH sub(4) super(+), NO sub(2) super(-), NO sub(3) super(-) and N sub(2)O) exchange were determined. Indirect estimates of nitrification corresponded to the burrow release of NO sub(2) super(-) without C sub(2)H sub(2). Approximately half of the NO sub(2) super(-) + NO sub(3) super(-) uptake in burrows was due to denitrification. In microcosms with and without N. virens), denitrification was stimulated 3-fold by N. virens  and the ratio denitrification/nitrification increased. The changes in DIN flux and denitrification caused by N. virens  corresponded well to the rates extrapolated from individual burrows to the appropriate worm density. At the abundance used, N. virens  burrows were responsible for 37% and 66% of the total sediment nitrification and denitrification, respectively.
AN: 2623582

                                                                   1081 of 1521  
TI: Fungi and their biomass in detritus of the seagrass Thalassia hemprichii  (Ehrenberg) Ascherson.
AU: Sathe,-V.; Raghukumar,-S.
AF: Biol. Oceanogr. Div., Natl. Inst. Oceanogr., Dona Paula, Goa 403 004, India
SO: BOT.-MAR. 1991. vol. 34, no. 4, pp. 271-277
LA: English
ER: M (Marine)
AB: Four different stages of detritus from the seagrass Thalassia hemprichii  from two coral islands in the Lakshadweep Archipelago, Arabian Sea were examined for the presence of fungi. Direct microscopic examination revealed different kinds of hyphae and unicellular thraustochytrid fungi, particularly in later stages of decomposition. Highest values of biomass estimated by direct observations were 31840 x 10 super(-6) g mycelial fungi per g dry wt. detritus in detrital fragments from the sediment and 2320 x 10 super(-6) g per g dry wt. of detritus for thraustochytrids in dark brown decaying leaves, corresponding to 3.2 and 0.23% per g dry wt. detritus respectively. The significance of these values which are higher than those reported for other submerged marine macrophyte detritus is discussed. Isolation of fungi in culture yielded thraustochytrids and terrestrial species of mycelial fungi from detritus.
AN: 2623405

                                                                   1082 of 1521  
TI: Time-dependent coupling of inorganic and organic nitrogen uptake and regeneration in the plume of the Chesapeake Bay estuary and its regulation by large heterotrophs.
AU: Glibert,-P.M.; Garside,-C.; Fuhrman,-J.A.; Roman,-M.R.
AF: Horn Point Environ. Lab., Univ. Maryland, P.O. Box 775, Cambridge, MD 21613, USA
SO: LIMNOL.-OCEANOGR. 1991. vol. 36, no. 3, pp. 895-909
LA: English
ER: B (Brackish)
AB: Nitrogen uptake and regeneration in the plume of the Chesapeake Bay estuary was studied during a series of four cruises (1985-1986). During each season we followed the short-term patterns in inorganic (NH sub(4) super(+), NO sub(3)-, NO sub(2) super(-)), and organic (urea and dissolved free amino acids--DFAA) nitrogen uptake and regeneration as plume water aged and became incorporated into ambient coastal water over 1-3 d. There was little influence of seasonally changing temperature on inorganic nitrogen uptake rates: the highest specific and absolute hourly rates of uptake occurred in April, when the availability of total N was at a seasonal high; rates were somewhat lower in early and late summer and were lowest in February. NH sub(4) super(+) regeneration rates, on the other hand, were highly correlated with temperature, with the highest rates occurring in late summer. Rates of DFAA uptake were highest in June. Urea contributed up to 70-80% of the total N utilized during winter and summer; in spring most nitrogen uptake was in the forms of NO sub(3) super(-) and NH sub(4) super(+). In winter most organic N release was not grazer mediated, but instead was more likely due to nutrient-deficient phytoplankton. In late summer, there seemed to be more dissolved organic N release by grazers.
AN: 2622244

                                                                   1083 of 1521  
TI: High turnover rates of dissolved organic carbon during a spring phytoplankton bloom.
AU: Kirchman,-D.L.; Suzuki,-Y.; Garside,-C.; Ducklow,-H.W.
AF: Coll. Mar. Stud., Univ. Delaware, Lewes, DE 19958, USA
SO: NATURE. 1991. vol. 352, no. 6336, pp. 612-614
LA: English
ER: M (Marine)
AB: The authors directly observed rapid dissolved organic carbon (DOC) turnover by bacterioplankton during the spring phytoplankton bloom in the North Atlantic ocean. Potential turnover rates, measured in 0.8- mu m filtered samples, ranged from 0.025 to 0.363 per day, and were consistent with bacterial biomass production and uptake of dissolved nitrogen (NH super(+)@)d4, NO super(-)@)d3 and urea). Our results indirectly suggest that cycling of dissolved organic nitrogen (DON) differs from that of DOC. The high estimates of DOC concentrations and turnover rates repeated here, if found to be general, would seem to demand changes in models of carbon cycling and of the ocean's role in buffering increases in atmospheric CO sub(2).
AN: 2622122

                                                                   1084 of 1521  
TI: The accumulation of barium by marine phytoplankton grown in culture.
AU: Fisher,-N.S.; Guillard,-R.R.L.; Bankston,-D.C.
AF: Mar. Sci. Res. Cent., State Univ. New York, Stony Brook, NY 11794-5000, USA
SO: J.-MAR.-RES. 1991. vol. 49, no. 2, pp. 339-354
LA: English
ER: M (Marine)
AB: Phytoplankton have been implicated as potentially important vectors for the vertical transport of barium in the oceans. To better assess the extent to which phytoplankton can affect the geochemical cycling of barium, its bioconcentration was studied in 21 clones of marine phytoplankters belonging to 9 algal classes. Dinoflagellates and several other algae not only concentrated Ba to relatively high levels, they also accumulated Si when grown in Si-enriched medium, although they grew at least as well without added Si as with it. Ba and Si accumulation were generally negatively correlated.
AN: 2621532

                                                                   1085 of 1521  
TI: Development and assessment of an analytical system for the accurate and continual measurement of total dissolved inorganic carbon.
AU: Robinson,-C.; Williams,-P.J.-leB.
AF: University Coll. North Wales, Sch. Ocean Sci., Menai Bridge LL59 5EY, UK
SO: MAR.-CHEM. 1991. vol. 34, no. 3-4, pp. 157-175
LA: English
ER: M (Marine)
AB: An automated coulometric titration system based on that described by Johnson, Sieburth, Williams and Brandstrom (1987, Mar. Chem., 21: 117-133) has been evolved for the accurate and continual measurement of total dissolved inorganic carbon (TCO sub(2)). The instrument achieves an analytical precision (1 SD) of  plus or minus  0.5-1.0  mu mol/kg (0.025-0.05%). The accuracy of the system has been examined by a limited comparison with other coulometric-based titrators and with a manometric-based system; agreement was to 1  mu mol/kg. The capability for automatic continual analysis allows surface mapping of TCO sub(2); a sample rate of 10 analyses/h gives a mapping resolution of 102 km. Provision for frequent standardization with a liquid substandard has been included in the development. The ability to achieve high-density analyses while maintaining interlaboratory consistency and standardization constitutes a vital contribution to surveys of ocean carbon chemistry (e.g. Joint Global Ocean Flux Study (JGOFS), World Ocean Circulation Experiment (WOCE)).
AN: 2620475

                                                                   1086 of 1521  
TI: Atmospheric deposition and nitrogen inputs to coastal waters.
AU: Hinga,-K.R.; Keller,-A.A.; Oviatt,-C.A.
AF: Mar. Ecosyst. Res. Lab., Grad. Sch. Oceanogr., Univ. Rhode Island, Narragansett, RI 02882, USA
SO: AMBIO. 1991. vol. 20, no. 6, pp. 256-260
LA: English
ER: M (Marine); B (Brackish)
AB: Recent reports have suggested that the fixed nitrogen which deposits from the atmosphere onto the watershed is a significant fraction of total anthropogenic loading of nitrogen to the Chesapeake Bay. A different approach was used here to estimate the atmospheric contribution of nitrogen to Narragansett Bay, the New York Bight, Ochlockonee Bay, Laholm Bay, and Chesapeake Bay. There is probably at least a factor of four uncertainty in loading estimates. The best estimates of the contribution of nitrogen reaching these ecosystems via emissions and deposition, relative to the total anthropogenic inputs of nitrogen, ranged from 11% to essentially 100%.
AN: 2618019

                                                                   1087 of 1521  
TI: Keystone species and mangrove forest dynamics: The influence of burrowing by crabs on soil nutrient status and forest productivity.
AU: Smith,-T.J.,III; Boto,-K.G.; Frusher,-S.D.; Giddins,-R.L.
AF: Rookery Bay Natl. Estuar. Res. Reserve, Florida Dep. Nat. Resour., 10 Shell Island Rd., Naples, FL 33962, USA
SO: ESTUAR.-COAST.-SHELF.-SCI. 1991. vol. 33, no. 5, pp. 419-432
LA: English
ER: M (Marine); B (Brackish)
AB: The density of the burrowing crab fauna in a mangrove forest was reduced, using pitfall traps, to test the hypothesis that decreased burrowing would lead to: increased soil sulphide concentrations; altered nutrient concentrations; and decreased forest productivity and growth. Experiments were conducted in Rhizophora -dominated forests in north Queensland, Australia, over a 12-month period. Crabs were trapped and removed from the experimental plots during 1 week each month for a year. Soil chemical and forest growth parameters were measured at monthly intervals in the experimental and appropriate control plots. Over the course of the experiment, soil sulphide and ammonium concentrations increased to levels which were significantly higher in plots from which crabs were being removed in comparison to controls.
AN: 2616466

                                                                   1088 of 1521  
TI: MASAS -- modelling of anthropogenic substances in aquatic systems on personal computers -- application to lakes.
AU: Ulrich,-M.; Schwarzenbach,-R.P.; Imboden,-D.M.
AF: Swiss Fed. Inst. Water Resour. and Water Pollut. Control (EAWAG), HC-8600 Duebendorf, Switzerland
SO: ENVIRON.-SOFTWARE. 1991. vol. 6, no. 1, pp. 34-38
LA: English
ER: F (Freshwater)
AB: MASAS is a computer simulation program for the evaluation of the dynamic behavior of anthropogenic organic micropollutants in aquatic systems, currently implemented for lakes. It allows a user to construct models of successively increasing complexity, and to build libraries with information for compounds and for lakes. Empirical and theoretical functions are included to approximate unknown parameters. The program is being implemented in Modula-2 as a user friendly tool for the Apple Macintosh personal computer. Availability: The program will be made available to interested persons/institutions (Diskette and User Manual) in fall 1990.
AN: 2615870

                                                                   1089 of 1521  
TI: Microbial processes affecting alanine and glutamic acid in anoxic marine sediments.
AU: Burdige,-D.
AF: Dep. Oceanogr., Old Dominion Univ., Norfolk, VA 23529-0276, USA
SO: FEMS-MICROBIOL.-ECOL. 1991. vol. 85, no. 3, pp. 211-232
LA: English
ER: M (Marine); B (Brackish)
AB: The utilization of glutamic acid and alanine in anoxic marine sediments was studied using sediments collected from a tidal flat on the Atlantic Ocean side of Virginia's Eastern Shore (Bordenstake Bay) and a site in the mid-Chesapeake Bay. The observations suggest that the general pathway of amino acid utilization in anoxic sediments involves their oxidation by fermentative bacteria to produce compounds such as volatile fatty acids or H sub(2) which are then themselves used as substrates by either sulfate reducing or methanogenic bacteria.
AN: 2615107

                                                                   1090 of 1521  
TI: Microbial degradation of methanesulphonic acid: A missing link in the biogeochemical sulphur cycle.
AU: Baker,-S.C.; Kelly,-D.P.; Murrell,-J.C.
AF: Dep. Biol. Sci., Univ. Warwick, Coventry CV4 7AL, UK
SO: NATURE. 1991. vol. 350, no. 6319, pp. 627-628
LA: English
AB: Atmospheric dimethyl sulphide, arising from marine algae, cyanobacteria and salt marsh plants such as Spartina , is the principal sulphur compound entering the atmosphere from terrestrial and aquatic environments. Methanesulphonic acid (CH sub(3)SO sub(3)H; MSA) has been identified as a major product of the photochemical oxidation in the atmosphere of dimethyl sulphide. Here we describe terrestrial bacteria that grow on MSA. Their activities in the natural environment would result in the mineralization of MSA to carbon dioxide and sulphate, thus completing our understanding of this part of the sulphur cycle.
AN: 2615059

                                                                   1091 of 1521  
TI: Contaminated marine sediments: Assessment and remediation.
AU: Swartz,-R.C.
CA: Environmental Protection Agency, Narragansett, RI (USA). Environmental Research Lab.
SO: ECOL.-RES.-SER.-U.S.-ENVIRON.-PROT.-AGENCY. 1990. 18 pp
NT: NTIS Order No.: PB91-132811/GAR. ERLN-N068.
RN: EPA/600/D-90/188 (EPA600D90188)
LA: English
ER: M (Marine)
AB: Sediment toxicity tests are part of several comprehensive methods for generating sediment quality criteria. Major research needs include test methods for chronic exposures, field validation of acute toxicity tests and the geochemical integrity of test materials, the relation between toxicity and the bioavailability/partitioning of contaminants in different sediment phases, models of toxicological interactions between sediment contaminants, and sediment wasteload allocation models. (Also publ. as Environmental Research Lab., Narragansett, RI., rept. no. CONTRIB-N068. Prepared in cooperation with National Research Council, Washington, DC. Marine Board.)
AN: 2613634

                                                                   1092 of 1521  
TI: Marine processes, their relationship to pollution, and a framework for waste management (chapter 1).
AU: Baumgartner,-D.J.; Duedall,-I.W.
CA: Environmental Protection Agency, Narragansett, RI (USA). Environmental Research Lab.
SO: ECOL.-RES.-SER.-U.S.-ENVIRON.-PROT.-AGENCY. 1990. 10 pp
NT: NTIS Order No.: PB91-132829/GAR. ERLN-N067.
RN: EPA/600/D-90/187 (EPA600D90187)
LA: English
ER: M (Marine)
AB: The transport and transformation processes which influence the way in which waste materials are dispersed and incorporated into the marine environment are reviewed and summarized as a preface for appreciation of the technical papers which follow in the volume. In a similar vein the papers are discussed in relation to an outline of a risk assessment framework which may be useful in guiding both regulatory action and future research. It is concluded that marine environmental process research has a role to play, but not an exclusive role in regulation. (Also pub. as Florida Inst. of Tech., Melbourne. rept. no. CONTRIB-139 and Environmental Research Lab., Narragansett, Newport, OR., Mark O. Hatfield Marine Science Center, rept. no. CONTRIB-N067. Pub. in Oceanic Processes in Marine Pollution Transformation, v6 Chapter 1, p3-11, 1990. Prepared in cooperation with Office of Technology Assessment, Washington, DC. Sponsored by Florida Inst. of Tech.)
AN: 2613628

                                                                   1093 of 1521  
TI: Flux and recycling of bioactive substances in the surface sediments of the deep basins off southern California: Progress report.
AU: Jahnke,-R.A.
CA: Scripps Inst. of Oceanography, San Diego, CA (USA)
SO: REP.-U.S.-DEP.-ENERGY. 1988. 10 pp
NT: NTIS Order No.: DE88007999/GAR.
RN: DOE/ER/60334-T1 (DOEER60334T1)
LA: English
AB: Goals of this project are to develop an understanding of the processes that recycling biogenic debris reaching the seafloor and to quantitatively determine the role of seafloor recycling in oceanic biogenic cycles. This includes evaluating the rate at which biogenic elements are released from the sediments due to organic matter decomposition as well as the rate at which certain biogenic elements are consumed in the sediments such as the consumption of O sub 2 by oxic respiration and NO sub 3/sup/minus/by dentrification. Benthic fluxes were estimated via the Bottom Lander. Results were combined with results from other West-coast researchers and a preliminary organic carbon budget for Santa Monica Basin was estimated. During the past year, benthic fluxes have been measured by a new in situ benthic chamber instrument and a shipboard incubation method. (Contract FG05-85ER60334. Portions illegible in microfiche.)
AN: 2613069

                                                                   1094 of 1521  
TI: Program of mineralization and cycling in marine systems: Organic geochemistry of particulates and sediments (CaBS): Progress report, November 15, 1987-November 14, 1988.
AU: Venkatesan,-M.I.; Kaplan,-I.R.
CA: California Univ., Los Angeles (USA)
SO: REP.-U.S.-DEP.-ENERGY. 1988. 14 pp
NT: NTIS Order No.: DE89005045/GAR.
RN: DOE/ER/60338-5 (DOEER603385)
LA: English
ER: M (Marine)
AB: The sources of organic carbon in southern California Bight derive from both terrestrial and marine regimes. The varied organic carbon sources can be reasonably delineated within limits by the organic geochemical approach of determining various characteristic biomarkers, as well as a variety of pollution indicators. The distributions of organic biomarker compounds are characteristic of marine algae, terrestrial vascular plants, bacteria, etc. Presence of specific biomarkers also indicate the occurrence of specific species (e.g., dinosterol specific of dinoflagellates). There are some pollution indicators which one can look for in the marine environment to trace their origin to terrestrial inputs, i.e., polycyclic aromatic hydrocarbons from petroleum and combustion coprostanol from sewage etc. (Contract FG05-85ER60338. Portions illegible in microfiche.)
AN: 2613036

                                                                   1095 of 1521  
TI: Scavenging retention of metals by zooplankton fecal pellets and marine snow.
AU: Fisher,-N.S.; Nolan,-C.V.; Fowler,-S.W.
AF: Mar. Sci. Res. Cent., State Univ. New York, Stony Brook, NY 11794-5000, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1991. vol. 38, no. 10A, pp. 1261-1275
LA: English
ER: M (Marine)
AB: The scavenging and retention of nine metals in different batches of zooplankton fecal pellets and marine snow were studied in the laboratory using radiotracer techniques. Dissolved  super(60)Co,  super(65)Zn,  super(106)Ru,  super(2109)Cd,  super(110m)Ag,  super(141)Ce,  super(154)Eu,  super(237)Pu and  super(241)Am were scavenged from seawater onto euphausiid fecal pellets, marine snow and copepod fecal pellets recovered from sediment traps and onto copepod fecal pellets freshly produced in the laboratory. K sub(d) values for the different radioisotopes ranged from 8.4 x 10 super(2) to 1.9 x 10 super(5). The radiolabeled fecal pellets and marine snow, resuspended into unlabeled seawater at 2 and 15 degree C, displayed metal depuration curves generally conforming to a two-compartment model, with overall retention half-times (t sub(r1/2)s) varying with each metal and type of debris. Our results provide direct evidence that fecal pellets and marine snow can effectively scavenge metals from seawater; of the metals examined, zinc and cadmium are likely to be remineralized most rapidly in surface waters, while the others are likely to be vertically transported hundreds to thousands of meters.
AN: 2612499

                                                                   1096 of 1521  
TI: Sedimentation of pteropods in the Norwegian Sea in autumn.
AU: Bathmann,-U.V.; Noji,-T.T.; von-Bodungen,-B.
AF: Alfred-Wegener-Inst. Polar- und Meeresforsch., 2850 Bremerhaven, FRG
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1991. vol. 38, no. 10A, pp. 1341-1360
LA: English
ER: M (Marine)
AB: Pteropod vertical distribution on the Voering Plateau (Norwegian Sea) was recorded during a 3 week drifting experiment during August 1988. Parallel to sampling of hydrographical, chemical and biological properties of the water column, sediment traps recorded vertical pelagic flux at five depth strata. Pteropods (Limacina retroversa ) dominated the zooplankton and reached maximum values (> 13,600 individuals/m super(3)) in the upper 25 m of the water column; the size spectrum shifted from small (< 1 mm) towards large (> 3 mm) specimens during the study. Vertical flux at 100 m depth increased from 600 mg dry weight/m super(2)/day to 1000 mg dry weight/m super(2)/day at the end of the experiment. Trap material during the first sampling intervals consisted primarily of phytoplankton and protozoans aggregated within pteropod feeding nets. Through their feeding, reproduction and subsequent mortality pteropods were the main contributors to vertical particle flux in the eastern Norwegian Sea during 1988.
AN: 2612451

                                                                   1097 of 1521  
TI: Benthic organic carbon degradation and biogenic silica dissolution in the central equatorial Pacific.
AU: Martin,-W.R.; Bender,-M.; Leinen,-M.; Orchardo,-J.
AF: Dep. Chem., Woods Hole Oceanogr. Inst., Woods Hole, MA 02543, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1991. vol. 38, no. 12A, pp. 1481-1516
LA: English
ER: M (Marine)
AB: Shipboard whole-core squeezing was used to measure pore water concentration vs depth profiles of NO sub(3)@)u-, O sub(2) and SiO sub(2) at 12 stations in the equatorial Pacific along a transect from 15 degree S to 11 degree N at 135 degree W. The NO sub(3)@)u- and SiO sub(2) profiles were combined with fine-scale resistivity and porosity measurements to calculate benthic fluxes. After using O sub(2) profiles, coupled with the NO sub(3)@)u- profiles, to constrain the C:N of the degrading organic matter, the NO sub(3)@)u- fluxes were converted to benthic organic carbon degradation rates. The range in benthic organic carbon degradation rates is 7-30  mu mol/cm super(2)/y, with maximum values at the equator and minimum values at the southern end of the transect. The zonal trend of benthic degradation rates, with its equatorial maximum and with elevated values skewed to the north of the equator, is similar to the pattern of primary production observed in the region. Benthic organic carbon degradation is 1-2% of primary production. The range of benthic biogenic silica dissolution rates is 6.9-20  mu mol/cm super(2)/y, representing 2.5-5% of silicon fixation in the surface ocean of the region. Its zonal pattern is distinctly different from that of organic carbon degradation.
AN: 2612410

                                                                   1098 of 1521  
TI: Seasonal uptake and regeneration of inorganic nitrogen and phosphorus in a large oligotrophic lake: Size-fractionation and antibiotic treatment.
AU: Dodds,-W.K.; Priscu,-J.C.; Ellis,-B.K.
AF: Div. Biol., Ackert Hall, Kansas State Univ., Manhattan, KS 66506, USA
SO: J.-PLANKTON-RES. 1991. vol. 13, no. 6, pp. 1339-1358
LA: English
ER: F (Freshwater)
AB: Uptake and regeneration of inorganic N and P in oligotrophic Flathead Lake (Montana, USA) were measured with  super(15)N and  super(32)P incorporation and dilution experiments, six times over a seasonal cycle. These results suggests that both N and P dynamics should be considered when examining nutrient regulation of primary productivity of oligotrophic lakes, bacteria probably compete with phytoplankton for both ammonium and phosphate, biotic regeneration is the main source of nutrients to the epilimnion during stratification, and crustacean zooplankton were relatively unimportant sources of regenerated ammonium and phosphate.
AN: 2612353

                                                                   1099 of 1521  
TI: Estimating organic P utilization by freshwater plankton using ( super(32)P)ATP.
AU: Bentzen,-E.; Taylor,-W.D.
AF: Dep. Biol., Univ. Waterloo, Waterloo, Ont. N2L 3G1, Canada
SO: J.-PLANKTON-RES. 1991. vol. 13, no. 6, pp. 1223-1238
LA: English
ER: F (Freshwater)
AB: The authors examined the use of ( super(32)P)ATP for the determination of dissolved organic phosphorus (DOP) utilization by freshwater plankton. Uptake of tracer amounts of  super(32)P from ATP into different size classes of plankton demonstrated that the bacterial size fraction (0.2-1  mu m) dominates uptake, but this domination diminishes when DOP concentrations are elevated. ( super(32)P)ATP is an effective and convenient substrate for tracing DOP dynamics in a manner comparable to using  super(32)PO sub(4) super(3-) to study PO sub(4) super(3-) dynamics.
AN: 2612271

                                                                   1100 of 1521  
TI: Accumulation and biological cycle of N and P elements in the Bruguiera sexangula  mangrove forest in Hainan, China.
AU: Lin,-Peng; Wu,-Xinhua
AF: Dep. Biol., Xiamen Univ., Xiamen, People's Rep. China
SO: J.-XIAMEN-UNIV.-NAT.-SCI.-XIAMEN-DAXUE-XUEBAO. 1990. vol. 29, no. 4, pp. 463-467
LA: Chinese
ER: M (Marine)
AB: This paper deals mainly with the accumulation and biological cycle of N and P elements of 55-year-old Bruguiera sexangula  community of Hainan Island, China. The amounts of N and P in the standing crop of this community were 1427.4 kg/ha and 165.7 kg/ha. In the biological cycle of N and P of this stand, the annual values of the vegetation mineral uptake were (kg/ha  multiplied by  yr) 190.0 for N and 24.1 for P. The turnover periods of N and P were 13 and 12 years respectively.
AN: 2611909

                                                                   1101 of 1521  
TI: Seasonal and depth-related changes in the source of sinking particles in the North Atlantic.
AU: Altabet,-M.A.; Deuser,-W.G.; Honjo,-S.; Stienen,-C.
AF: Woods Hole Oceanogr. Inst., Woods Hole, MA 02543, USA
SO: NATURE. 1991. vol. 354, no. 6349, pp. 136-139
LA: English
ER: M (Marine)
AB: Large, fast-sinking particles are important in the downward transport and redistribution of biogeochemical species in the deep ocean. Using nitrogen isotope ratio,  super(15)N/ super(14)N, as an in situ tracer, we investigate the source and transformation of these particles in the North Atlantic ocean. We observe seasonal variations in  delta  super(15)N associated with seasonal changes in near-surface nitrate concentration and particle flux; the nitrogen isotope variations are consistent with, but much larger than, previously observed variability. Our results show that the signal from these near-surface changes propagates rapidly into the deep ocean, but is modified depending on the phase of the seasonal production cycle. Surprisingly, we find that  delta  super(15)N values of sinking particles decrease with depth during low-flux periods--behaviour that may occur generally in the open ocean. The sinking particles must therefore be either gaining light nitrogen or losing heavy nitrogen, an effect that we believe requires there to be another source of sinking particles, apart from recent surface production.
AN: 2611636

                                                                   1102 of 1521  
TI: An input/output flux for lead in a coastal bay off Alexandria region.
AU: Abdel-Moati,-A.R.
AF: Oceanogr. Dep., Fac. Sci., Alexandria Univ., Moharam Bay, Alexandria, Egypt
SO: WATER-AIR-SOIL-POLLUT. 1991. vol. 59, no. 3-4, pp. 261-269
LA: English
ER: M (Marine)
AB: During 1987, seawater, rain, dust and drainage water samples were collected from Abu-kir bay (360 km super(2)) east of Alexandria city to set up and evaluate the relative importance of different sources to the biogeochemical cycle of Pb in the bay. The mean total concentration of Pb in the bay water was 455  plus or minus  180 and 785  plus or minus  287 ng/kg during low and high flow periods, respectively. About 75  plus or minus  12% are in the particulate form. The bay receives annually about 8.12  plus or minus  2.18 and 6.13  plus or minus  1.06 t of Pb through agricultural and industrial discharge. In addition, 0.48  plus or minus  0.11 t/yr and 0.23  plus or minus  0.04 t/yr of Pb reaches the bay through wet and dry depositions, respectively. The outflowing surface water from the bay carries 15.4  plus or minus  3.6 t Pb/yr to the southeastern Mediterranean waters. Data from sedimentation traps indicated that the bulk sedimentation rate in the bay was 95  plus or minus  18 kg/yr elevating the concentrations of Pb in sediments to more than 64  mu g/g. The imbalance in the Pb flux (excess + 0.6 + 0.08 t) indicates Pb accumulation in the water column.
AN: 2606461

                                                                   1103 of 1521  
TI: Trace metal distribution in the coastal waters of Visakhapatnam.
AU: Prabhakaramurty,-P.V.S.; Satyanarayana,-D.
AF: Sch. Chem., Andhra Univ., Waltair, Visakhapatnam 530 003, India
SO: INDIAN-J.-ENVIRON.-PROT. 1990. vol. 10, no. 12, pp. 919-925
LA: English
ER: M (Marine)
AB: The concentration levels of dissolved and particulate trace metals (Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb) were determined in the coastal waters of Visakhapatnam, Andhra Pradesh, India, along 3 transects (Gangavaram, Harbour and Rushi Hill) at monthly intervals over a period of one year (September 1986 to August 1987). The results indicated distinct spatial and temporal variations in the study region. Dissolved and particulate fractions of Mn, Fe, Cu, Zn, Cd showed surface depletion and bottom enrichment due to their involvement in the biogeochemical cycle leading to their removal in surface and release at bottom waters. On the other hand, dissolved and particulate Pb recorded surface enrichment and bottom depletion due to anthropogenic atmospheric input. Comparison of concentration levels of trace metals obtained in the present study with earlier reports demonstrates the extent of pollution in the harbour and its impact on the coastal environment of Visakhapatnam.
AN: 2605976

                                                                   1104 of 1521  
TI: Phosphorus cycling by mussels (Unionidae: Bivalvia) in Lake St. Clair.
AU: Nalepa,-T.F.; Gardner,-W.S.; Malczyk,-J.M.
AF: Great Lakes Environ. Res. Lab., 2205 Commonwealth Blvd., Ann Arbor, MI 48105, USA
CO: Symp. on Environmental Assessment and Habitat Evaluation in the Upper Great Lakes Connecting Channels (at) 31. Conf. on Great Lakes Research, Hamilton, Ont. (Canada), 1988
SO: ENVIRONMENTAL-ASSESSMENT-AND-HABITAT-EVALUATION-OF-THE-UPPER-GREAT-LAKES-CONNECTING-CHANNELS. Munawar,-M.;Edsall,-T.-eds. 1991. vol. 219 pp. 229-250
ST: HYDROBIOLOGIA. vol. 219
LA: English
ER: F (Freshwater)
AB: The role of mussels in cycling phosphorus in Lake St. Clair, North America, during the May-Oct. period was examined by measuring concentrations in the water column and in mussel tissue, and by measuring rates of biodeposition and excretion. Mean rates of biodeposition and excretion for Lampsilis radiata siliquoidea , the most abundant species, were 6.3  mu g/P (g shell-free dry wt)/h and 1.3  mu g/P (g shell-free dry wt)/h, respectively; body tissue phosphorus content was 2.7 percent of dry wt. Seasonal changes in excretion rates appeared to be related to the gametogenic cycle of the organism, but seasonal changes in biodeposition rates were not apparent. Phosphorus assimilation efficiency for this species was about 40 percent. Overall, the mussel population in Lake St. Clair filtered about 21 MT of phosphorus, or about 13.5 percent of the total phosphorus load for the May-Oct. study period. Of this amount, about 134 MT was sedimented to the bottom via biodeposition. Mussel biodeposition may be an important source of nutrients to other biotic components in the lake such as macrophytes and invertebrate deposit-feeders.
AN: 2603326

                                                                   1105 of 1521  
TI: Chloride cycling in two forested lake watersheds in the west-central Adirondack Mountains, New York, U.S.A.
AU: Peters,-N.E.
AF: U.S. Geol. Surv., 6481-B Peachtree Industrial Blvd., WRD, Doraville, GA 30360, USA
SO: WATER-AIR-SOIL-POLLUT. 1991. vol. 59, no. 3-4, pp. 201-215
LA: English
ER: F (Freshwater)
AB: The chemistry of precipitation, throughfall, soil water, ground water, and surface water was evaluated in two forested lake-watersheds over a 4-yr period to assess factors controlling Cl super(-) cycling. Results indicate that Cl super(-) cycling in these watersheds is more complex than the generally held view of the rapid transport of atmospherically derived Cl super(-) through the excosystem. The annual throughfall Cl super(-) flux for individual species in the northern hardwood forest was 2 to 5 times that of precipitation (56 eq/ha), whereas the Na super(+) throughfall flux, in general, was similar to the precipitation flux. Concentrations of soil-water Cl super(-) sampled from ceramic tension lysimeters at 20 cm below land surface generally exceeded the Na super(+) concentrations and averaged 31  mu eq/L, the highest of any waters sampled in the watersheds, except throughfall under red spruce which averaged 34  mu eq/L. Chloride was concentrated prior to storms and mobilized rapidly during storms as suggested by increases in streamwater Cl super(-) concentrations with increasing flow.
AN: 2603287

                                                                   1106 of 1521  
TI: Empirical methods in the design of groundwater quality monitoring strategies.
AU: Rajagopal,-R.
AF: Dep. Geogr., 302 Jessup Hall, Univ. Iowa, Iowa City, IA 52242, USA
CO: Natl. Conf. on Hydraulic Engineering, New Orleans, LA (USA), 14-18 Aug 1989
SO: HYDRAULIC-ENGINEERING.-PROCEEDINGS-OF-THE-1989-NATIONAL-CONFERENCE-ON-HYDRAULIC-ENGINEERING. Ports,-M.A.-ed. 1989. pp. 416-421
LA: English
ER: F (Freshwater)
AB: Ground-water quality monitoring strategies are designed for environments ranging from the most complex to the very simple. Complexity is characterized by socio-economic, public health, and biogeochemical interactions in space and time. Arguments are offered to show that empirical methods are cost-effective for the more complex, while process-based methods are appropriate for the relatively simpler environments.
AN: 2603251

                                                                   1107 of 1521  
TI: Lipids of cultured Phaeocystis pouchetii : Signatures for food-web, biogeochemical and environmental studies in Antarctica and the Southern Ocean.
AU: Nichols,-P.D.; Skerratt,-J.H.; Davidson,-A.; Burton,-H.; McMeekin,-T.A.
AF: CSIRO Div. Oceanogr., G.P.O. Box 1538, Hobart, Tas. 7001, Australia
SO: PHYTOCHEMISTRY. 1991. vol. 30, no. 10, pp. 3209-3214
LA: English
ER: M (Marine)
AB: The lipid, fatty acid, sterol and pigment composition of cultured Phaeocystis pouchetii  were analysed by capillary GC, GC-MS, TLC-FID and HPLC. Polar lipids were the dominant class. Significant variation occurred between strains in the amount of lipid per cell; lipid content varied from 3.5 pg/cell for the axenic spherical colony forming strain A1-3, to 8.2 pg/cell for the largely flagellate strain DE10 and 7.7 pg/cell for the benthic strain. The dominant sterol was 24-methylcholesta-5,22E-dien-3 beta -ol irrespective of culture age or life stage composition. The major fatty acids for strain A1-3 were: 16:0, 18:1 omega 9c, 14:0 and 18:0, while profiles for strains DE10 and A1-4 contained 14:0, 16:0, 18:1 omega 9c and 18:0. The essential fatty acids 20:5 omega 3 and 22:6 omega 3 were only minor or trace components, demonstrating the poor nutritional quality (with respect to fatty acids) of Phaeocystis  to Antarctic grazers. However, the lipid and fatty acid content of the strains indicate that the flagellate stage is of greater nutritional value than the free floating colonies, and that the flagellate and benthic colonial stages are most biochemically alike. The major pigments in all strains were chlorophylls a and c and 19'-hexanoyloxyfucoxanthin. Minor carotenoids detected were 19'-butanoyloxyfucoxanthin, fucoxanthin, diadinoxanthin and diatoxanthin.
AN: 2601006

                                                                   1108 of 1521  
TI: The distribution of dissolved DNA in an oligotrophic and a eutrophic river of Southwest Florida.
AU: Paul,-J.H.; Cazares,-L.H.; David,-A.W.; DeFlaun,-M.F.; Jeffrey,-W.H.
AF: Dep. Mar. Sci., Univ. South Florida, 140 7th Ave. S., St. Petersburg, FL 33701, USA
SO: HYDROBIOLOGIA. 1991. vol. 218, no. 1, pp. 53-63
LA: English
ER: F (Freshwater)
AB: The distribution of dissolved DNA concentrations and some microbial variables were compared in an oligo-mesotrophic river (the Crystal River) and a phosphate-rich eutrophic river (the Alafia River) in Southwest Florida over a 15-mo. period. The greatest concentrations of dissolved DNA in the Alafia River were found in areas that contained the largest populations of phytoplankton and bacteria. Differences in dissolved DNA concentrations between these environments and more pristine environments were of the same order of magnitude (1.8 to 2.2-fold) as the differences in bacterial abundance and activity, but considerably less than differences in phytoplankton abundance and activity between such environments. Results suggest that: 1) in situ planktonic activity is a greater source of dissolved DNA than allochthonous or terrestrial sources of DOC; 2) factors that control the magnitude of heterotrophic bacterial populations are more likely to control dissolved DNA levels than factors regulating autotrophic population activity and abundance; 3) differences in dissolved DNA between eutrophic and oligo-mesotrophic environments are often much smaller than the differences in nutrient concentration between such environments.
AN: 2600452

                                                                   1109 of 1521  
TI: Circulation and exchange processes on the South Atlantic Bight continental shelf: Progress report, July 1, 1988 to June 30, 1989.
AU: Lee,-T.N.
CA: Miami Univ., FL (USA). Rosenstiel Sch. of Marine and Atmospheric Sciences
SO: REP.-U.S.-DEP.-ENERGY. 1989. 51 pp
NT: NTIS Order No.: DE89010065/GAR. Contract FG05-85ER60355.
RN: DOE/ER/60355-4 (DOEER603554)
LA: English
ER: M (Marine)
AB: The work Department of Energy sponsored Southeast US Continental Shelf program is a coordinated, multi-university, interdisciplinary investigation aimed at understanding the physical, chemical and biological processes in the South Atlantic Bight (SAB: east coast continental shelf region from Cape hatteras to Cape Canaveral). The activities of the other Program Investigators are discussed. The University of Miami component of the program involves an investigation of the physical processes regulating the transport and exchange of materials in the shelf waters. The guiding scientific objective of this work is to improve the capability for prediction of the physical environment. The principal scientific task is to determine the relative importance of the forces driving shelf circulation and exchange and to measure the shelf waters' response over variable time and space scales. The influence of physical processes on chemical and biological distributions and their interactions is studied through interdisciplinary investigations, joint analysis and interpretation of data and joint publications.
AN: 2600361

                                                                   1110 of 1521  
TI: Relationships between seepage chemistry and flow path through the near-shore sediments of an acidic lake.
AU: Schafran,-G.C.; Driscoll,-C.T.
AF: Dep. Civil Eng., Old Dominion Univ., Norfolk, VA 23529, USA
CO: 23. Congress in New Zealand, (Hamilton (New Zealand)), 8 Feb 1987
SO: CONGRESS-IN-NEW-ZEALAND-1987.-PROCEEDINGS. Sladecek,-V.-ed. 1988. vol. 23, no. 4 pp. 2262-2266
ST: VERH.-INT.-VER.-THEOR.-ANGEW.-LIMNOL.-PROC.-INT.-ASSOC.-THEOR.-APPL.-LIMNOL.-TRAV.-ASSOC.-INT.-LIMNOL.-THEOR.-APPL. vol. 23, no. 4
LA: English
ER: F (Freshwater)
AB: It was the focus of this study to investigate the variation of ground water inputs in the near-shore region of an acid lake and to assess the biogeochemical processes occurring within the near-shore sediments that influence seepage chemistry. Dart's Lake in the Adirondack Mountain region of New York State, U.S.A., was the site of this investigation. These results indicate that seepage chemistry is highly dependent on the flow path and is consistent with earlier studies that reported the importance of the hydrologic pathway in controlling groundwater chemistry.
AN: 2595876

                                                                   1111 of 1521  
TI: Radium accumulation from water by foliage of the water lily, Nymphaea violacea .
AU: Twining,-J.R.
AF: Environ. Sci. Div., Aust. Nucl. Sci. and Technol. Organ, Lucas Heights Res. Lab., Lock Mail Bag No. 1, Menai, N.S.W. 2234, Australia
CO: (23.) Congress in New Zealand, (Hamilton (New Zealand)), 8 Feb 1987
SO: CONGRESS-IN-NEW-ZEALAND-1987.-PROCEEDINGS. Sladecek,-V.-ed. 1988. vol. 23, no. 4 pp. 1954-1962
ST: VERH.-INT.-VER.-THEOR.-ANGEW.-LIMNOL.-PROC.-INT.-ASSOC.-THEOR.-APPL.-LIMNOL.-TRAV.-ASSOC.-INT.-LIMNOL.-THEOR.-APPL. vol. 23, no. 4
LA: English
ER: F (Freshwater)
AB: Radium-226 is a possible contaminant from the Ranger Uranium Mine at Jabiru, 240 km east of Darwin, in the Northern Territory of Australia. The Magela Creek floodplain, 10 km downstream supports large populations of Nymphaea violacea  during the period of inundation from Dec to Jun. The plant is important because it is a traditional food of aboriginal people has a possible role in the biogeochemical cycling of radium. This work set out to assess the rates and extent of uptake and loss of radium by the foliage of N. violacea  under laboratory conditions and to identify parameters likely to influence accumulation.
AN: 2595431

                                                                   1112 of 1521  
TI: The global beryllium 10 cycle.
AU: McHargue,-L.R.; Damon,-P.E.
AF: NSF-Arizona Facil. Radioisot. Anal., Dep. Geosci., Univ. Arizona, Tucson, AZ 85721, USA
SO: REV.-GEOPHYS. 1991. vol. 29, no. 2, pp. 141-158
LA: English
AB: The cosmogenic radionuclide  super(10)Be has generated much interest because of its potential as a tracer in the environment and applications to geology, archaeology, glaciology, and oceanography. Nevertheless, for  super(10)Be to be useful as a tool in the Earth sciences its geochemical cycle as outlined below needs to be understood more fully. Beryllium 10 (t sub(1/2) = 1.5 x 10 super(6) years) is mainly produced in the atmosphere by spallation of oxygen and nitrogen induced by secondary neutrons formed by cosmic ray interactions with the atmosphere, but some is produced in situ on the surface of the Earth. Deposition of  super(10)Be onto the surface of the Earth depends primarily on precipitation. Deposited  super(10)Be is made up of several components, primarily  super(10)Be produced in the stratosphere and in the troposphere and  super(10)Be recycled from dust and soil particles, and secondarily  super(10)Be recycled from the ocean as hygroscopic nuclei and from cosmic dust.
AN: 2594273

                                                                   1113 of 1521  
TI: Molecular biology in studies of ocean processes.
AU: Falkowski,-P.G.; LaRoche,-J.
AF: Oceanogr. and Atmos. Sci. Div., Brookhaven Natl. Lab., Upton, NY 11973, USA
SO: INT.-REV.-CYTOL. 1991. vol. 128, pp. 261-304
LA: English
ER: M (Marine)
AB: The authors describe potential applications of molecular biological techniques to study specific biological oceanographic processes. Molecular techniques are particularly useful and undoubtedly will continue to be used to understand the evolution of organisms, gene flow, and population genetics, and to construct phylogenetic trees. They also suggest the potential application of molecular techniques to understanding molecular mechanisms of key biogeochemical processes, such as nitrification, carbon fixation, silica incorporation, and iron limitation. While an understanding of mechanisms may not provide quantitative rate information, which is often desired by oceanographers, it provides a basis for understanding how physical and chemical ocean environments are related to complex biological phenomena.
AN: 2594223

                                                                   1114 of 1521  
TI: An integrated watershed/plot-scale study of element cycling in spruce ecosystems of the Black Forest.
AU: Feger,-K.-H.; Grahmer,-G.; Zoettl,-H.W.
AF: Inst. Soil Sci. and Forest Nutr., Albert-Ludwigs-Univ., Bertoldstr. 17, D-7800 Freiburg i.Br., FRG
CO: Int. Symp. on Management of Nutrition in Forests Under Stress, Freiburg (FRG), 18-21 Sep 1989
SO: WATER-AIR-SOIL-POLLUT. 1990. vol. 54, no. special, pp. 545-560
LA: English
ER: F (Freshwater)
AB: The research project ARINUS is the study of the effects of restabilization measures (fertilization with rapidly soluble Mg salts) and atmospheric deposition on the element cycling of typical spruce ecosystems in the Black Forest. The objective is to quantify the natural and anthropogenic components of element cycling at these sites which will provide a better estimation of the effects induced by external perturbations, e.g. increasing atmospheric deposition, fertilization, or biomass export. Interrelations between the terrestrial and aquatic system are assessed using an integrated approach which combines flux measurements in representative plots with balances of small experimental watersheds. This paper describes the approach, treatments, field installations, methods, and site conditions of one of the two research areas.
AN: 2591051

                                                                   1115 of 1521  
TI: Estimation of new production in the ocean by compound remote sensing.
AU: Sathyendranath,-S.; Platt,-T.; Horne,-E.P.W.; Harrison,-W.C.; Ulloa,-O.; Outerbridge,-R.; Hoepffner,-N.
AF: Biol. Oceanogr. Div., Bedford Inst. Oceanogr., Box 1006, Darmouth, N.S. B2Y 4A2, Canada
SO: NATURE. 1991. vol. 353, no. 6340, pp. 129-133
LA: English
ER: M (Marine)
AB: Oceanic new production can be estimated from remotely sensed data on ocean colour and temperature. This approach, which depends on parameterizations developed from ship observations, as well as on satellite data, yields more representative estimates of the large-scale average new production than those calculated from ship data alone.
AN: 2581899

                                                                   1116 of 1521  
TI: Do upper-ocean sediment traps provide an accurate record of particle flux?.
AU: Buesseler,-K.O.
AF: Woods Hole Oceanogr. Inst., Woods Hole, MA 02543, USA
SO: NATURE. 1991. vol. 353, no. 6343, pp. 420-423
LA: English
ER: M (Marine)
AB: Sediment traps are widely used to measure the vertical flux of particulate matter in the oceans. In the upper ocean, sediment traps have been used to determine the extent to which CO sub(2) fixed by primary producers is exported as particulate organic carbon. In addition, the observed decrease of particle flux with depth has been use to predict regeneration rates of organic matter and associated elements. Over seasonal or annual timescales, the import of limiting nutrients into the upper ocean (new production) should be balanced by particle export. Given the importance of accurately determining the sinking particle flux, it has been suggested that  super(234)Th might be used to "calibrate" shallow-trap fluxes. The author presents a re-evaluation of existing  super(234)Th data which indicates that trap-derived and model-derived  super(234)Th particle fluxes can differ by a factor of  plus or minus 3-10, suggesting that shallow traps may not provide an accurate measure of particle fluxes.
AN: 2580752

                                                                   1117 of 1521  
TI: Some aspects of deep-sea microbiology with emphasis on the environment of the Southern Ocean.
AU: Helmke,-E.; Weyland,-H.
AF: Alfred-Wegener-Inst. Polar and Mar. Res., Bremerhaven, FRG
CO: 2. Int. Marine Biotechnology Conf. (IMBC '91), Baltimore, MD (USA), 13-16 Oct 1991
SO: PROGRAM-AND-ABSTRACTS.-SECOND-INTERNATIONAL-MARINE-BIOTECHNOLOGY-CONFERENCE-IMBC-'-91. 1991. p. 73
NT: Abstract only.
LA: English
ER: M (Marine)
AB: Although our knowledge about deep-sea and especially about deep-sea adapted barophilic bacteria has increased significantly in the last ten years, the role and importance of these organisms in the food web and biogeochemical cycles as well as the linkage of psychrophilism and barophilism is not yet clear. The Southern Ocean with low temperatures throughout the entire water column proved to be an ideal area for studying these questions. Using a variety of methodological approaches employing both water and sediment samples considerable information was collected to support the idea that cold adapted barophilic bacteria are functionally dominant, at least in the abyssal zone. On the other hand cold adapted bacteria from the surface area were found to be extremely pressure sensitive.
AN: 2579804

                                                                   1118 of 1521  
TI: Aragonite and magnesian calcite fluxes to the deep Sargasso Sea.
AU: Fabry,-V.J.; Deuser,-W.G.
AF: Int. Lab. Mar. Radioact., 19 Ave. des Castellans, MC-98000, Monaco
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1991. vol. 38, no. 6A, pp. 713-728
LA: English
ER: M (Marine)
AB: Aragonite and magnesian calcite fluxes were estimated from a 14-month series of sediment trap samples from depths of 500, 1500 and 3200 m in the Sargasso Sea. No significant difference with depth was observed in fluxes of either carbonate phase. At 3200 m, the mean aragonite flux was 2.8 mg/m super(2)/day, or 13% of the total CaCO sub(3) flux. At all depths pteropods were the major source of aragonite, contributing more carbonate than heteropods by a factor of 3-24. Most of the pteropod aragonite occurred in the size fraction > 0.5 mm. At 3200 m, more than half of the pteropod mass flux in the size fraction > 0.5 mm comprised four species: Styliola subula, Clio pyramidata, Limacina inflata) and Cuvierina columnella . The mean magnesian calcite flux at 3200 m was 1.7 mg/m super(2)/day, or 8% of the total CaCO sub(3) flux. The majority of the magnesian calcite (9-12 mole % MgCO sub(3)) occurred in the finest size fraction, < 37  mu m. Evidence suggests that bryozoans attached to floating Sargassum) are the source of this magnesian calcite. The combined fluxes of aragonite and magnesian calcite accounted for 21-25% of the mean annual CaCO sub(3) flux to 1500 and 3200 m.
AN: 2579704

                                                                   1119 of 1521  
TI: Heterotrophic bacterial activity and growth rates in sediments of the continental margin of eastern Australia.
AU: Moriarty,-D.J.W.; Skyring,-G.W.; O'-Brien,-G.W.; Heggie,-D.T.
AF: CSIRO, Div. Fish., P.O. Box 120, Cleveland, Qld. 4163, Australia
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1991. vol. 38, no. 6A, pp. 693-712
LA: English
ER: M (Marine)
AB: The numbers, growth rates and productivity of heterotrophic bacteria were determined in sediment cores collected on the East Australian continental margin (28 and 32 degree S) at water depths ranging from 150 to 1000 m. The study was centered on a zone of modern phosphate nodule formation (350-460 m water depth), as bacteria had previously been implicated in the genesis of the modern phosphorites in this area. About 80% of bacterial productivity occurred in the upper 2 cm of sediment, although bacteria found at depths up to 70 cm in the sediment were capable of metabolic activity. Rates of phospholipid and protein synthesis were also determined and, when converted to productivity, the values in the upper 2 cm of sediment were mostly within a factor of 2 or 3 of values determined from DNA synthesis. Similar values were obtained for the flux of the organic carbon into the sediments, required to support metabolic activity, whether calculated from values for bacterial productivity or from a geochemical model of oxygen diffusion and consumption, using profiles of oxygen concentration in the sediments.
AN: 2579667

                                                                   1120 of 1521  
TI: Three-dimensional modeling of the global atmospheric sulfur cycle: A first step.
AU: Erickson,-D.J.,III; Walton,-J.J.; Ghan,-S.J.; Penner,-J.E.
AF: Scripps Inst. Oceanogr., A-024, La Jolla, CA 92093, USA
CO: Symp. on Global Climatic Effects of Aerosols, Reno, NV (USA), 11-13 Oct 1989
SO: ATMOS.-ENVIRON.,-PART-A. 1991. vol. 25A, no. 11, pp. 2513-2520
LA: English
ER: M (Marine)
AB: Atmospheric sulfur is known to be a major source of condensation nuclei (CN). Over continents the major source of sulfur is believed to be SO sub(2) emitted from industrial regions. Over remote marine regions, emission of biogenic dimethylsulfide (DMS) from the ocean surface is thought to be the major source of non-sea-salt sulfate and of CN. Here researchers apply a global three-dimensional model with a simplified treatment of the atmospheric sulfur cycle to address the question of whether anthropogenic sulfur transported from continents might impact marine CN concentrations over a significant fraction of the world's oceans. Processes treated in the model include transport, convective and eddy mixing, a simplified treatment of the conversion of SO sub(2) and DMS to form the condensate SO sub(4)@) super(2)- )removal of SO sub(2) and SO sub(4)@) super(2)-b)y dry deposition and wet deposition of SO sub(4)@) super(2)- )
AN: 2578904

                                                                   1121 of 1521  
TI: Geophysiology of natural marine sulfate aerosols.
AU: Anderson,-T.L.; Charlson,-R.J.
AF: Dep. Atmos. Sci., Univ. Washington, Seattle, WA 98195, USA
CO: Symp. on Global Climatic Effects of Aerosols, Reno, NV (USA), 11-13 Oct 1989
SO: ATMOS.-ENVIRON.,-PART-A. 1991. vol. 25A, no. 11, pp. 2445-2447
LA: English
ER: M (Marine)
AB: The hypothesis suggesting dimethyl sulfide (DMS) from oceanic phytoplankton as the dominant natural worldwide source of cloud condensation nuclei (CCN) is being tested in several ways. Studies ranging from the perturbation of cloud albedo by ship plumes to the sulfur content of Antarctic ice cores have revealed much about the working of the natural marine sulfur cycle and the mass flux of DMS-derived sulfur compounds. However, quantifying the relationship between DMS mass flux, or sulfate mass concentration, and CCN number remains as a major challenge.
AN: 2578834

                                                                   1122 of 1521  
TI: Aerosol formation during photooxidation of organosulfur species.
AU: Kreidenweis,-S.M.; Yin,-F.-D.; Wang,-S.-C.; Grosjean,-D.; Flagan,-R.C.; Seinfeld,-J.H.
AF: Dep. Chem. Eng., San Jose State Univ., San Jose, CA 95192, USA
CO: Symp. on Global Climatic Effects of Aerosols, Reno, NV (USA), 11-13 Oct 1989
SO: ATMOS.-ENVIRON.,-PART-A. 1991. vol. 25A, no. 11, pp. 2491-2500
LA: English
ER: M (Marine)
AB: The most abundant marine organosulfur species is dimethylsulfide (DMS), with an estimated overall flux from the world oceans of 40 plus or minus 20 Tg S/yr. This flux is a significant fraction of the global biogenic S emissions, and an understanding of the atmospheric chemistry of reduced sulfur compounds, including DMS and dimethyldisulfide (DMDS), is needed to evaluate their role in the global S budget. Measurements of aerosol formation during the photooxidation of DMS and DMDS in an outdoor smog chamber are compared with predictions from a model of aerosol nucleation and growth in the chemically reacting system. The aerosol is assumed to consist of methanesulfonic acid (MSA), sulfuric acid, and water. Source rates of the two acid species are obtained from a detailed chemical mechanism for the organosulfur precursor oxidation and are used to drive the aerosol model. Good agreement between experiment and predictions was observed for DMDS and DMS oxidation in the presence of NO sub(x), but maximum total number concentrations achieved during DMDS oxidation in the absence of NO sub(x) were somewhat underpredicted. The effect upon model predictions of variations in model input parameters is evaluated.
AN: 2578774

                                                                   1123 of 1521  
TI: Derivation and analysis of flow networks for open ocean plankton systems.
AU: Ducklow,-H.W.; Fasham,-M.J.R.; Vezina,-A.F.
AF: Horn Point Environ. Lab., Box 775, Cambridge, MD 21601, USA
SO: NETWORK-ANALYSIS-IN-MARINE-ECOLOGY.-METHODS-AND-APPLICATIONS. Wulff,-F.;Field,-J.G.;Mann,-K.H.-eds. 1989. vol. 32 pp. 159-205
ST: COAST.-ESTUAR.-STUD. vol. 32
LA: English
AB: Details are given of the production of an open ocean flow network, which could include a realistic depiction of a foodweb. Two complementary approaches were used to derive models of flow networks: an a priori steady state input-output flow analysis and an inverse approach. The results of analyses of network structure, Lindeman Trophic Aggregations and biogeochemical cycles are discussed.
AN: 2577862

                                                                   1124 of 1521  
TI: Separation of runoff components in a small mountainous watershed using stream solute data.
AU: Hirata,-T.; Muraoka,-K.
AF: Natl. Inst. Environ. Stud., Onogawa 16-2, Tsukuba, Ibaraki 305, Japan
CO: (23.) Congress in New Zealand, (Hamilton (New Zealand)), 8 Feb 1987
SO: CONGRESS-IN-NEW-ZEALAND-1987.-PROCEEDINGS. Sladecek,-V.-ed. 1988. vol. 23, no. 3 pp. 1354-1361
ST: VERH.-INT.-VER.-THEOR.-ANGEW.-LIMNOL.-PROC.-INT.-ASSOC.-THEOR.-APPL.-LIMNOL.-TRAV.-ASSOC.-INT.-LIMNOL.-THEOR.-APPL. vol. 23, no. 3
LA: English
ER: F (Freshwater)
AB: This study presented streamwater chemistry results obtained in the Tsukuba experimental forested basin, a basin designed to provide a basic understanding of nutrient dynamics in forest ecosystems. Rainfall, groundwater and streamwater were investigated since September 1984. On the basis of the observed data, the responses of the dissolved materials in the streamwater chemistry to the rainfall were used to examine runoff sources. Further contributors to the streamwater during rainfall events are examined by the use of runoff separation with an environmental tracer.
AN: 2575837

                                                                   1125 of 1521  
TI: Riparian zone as a source of phosphorus for a groundwater-dominated lake.
AU: Vanek,-V.
AF: Dep. Ecol.-Limnol., Univ. Lund, P.O. Box 65, S-221 00 Lund, Sweden
SO: WATER-RES. 1991. vol. 25, no. 4, pp. 409-418
LA: English
ER: F (Freshwater)
AB: Groundwater entering Lake Bysjoen in southern Sweden is somewhat higher in specific conductance and up to 20 times higher in phosphate than the mean for the lake. This leads to elevated values of both specific conductance and phosphate in lake water within a 500 m long and several meter wide strip along the shore. In areas not influenced by groundwater inflow, specific conductance and phosphorus content near the shore are close to that of open lake water. High concentrations of phosphate (up to 9 mg/l PO sub(4)-P) in the inflowing groundwater originate from the riparian zone surrounding the lake. It is suggested that, over a long time, this ecotone has accumulated phosphorus and other nutrients that were transported from the adjacent developed areas and arable land. This phosphorus is now entering the lake, probably as a result of increased decomposition of organic matter.
AN: 2574769

                                                                   1126 of 1521  
TI: Production and major nutrient composition of three grass species on the Magela floodplain, Northern Territory, Australia.
AU: Finlayson,-C.M.
AF: Alligator Rivers Reg. Res. Inst., Off. Superv. Sci., Post Off., Jabiru, N.T. 0886, Australia
SO: AQUAT.-BOT. 1991. vol. 41, no. 4, pp. 263-280
LA: English
ER: F (Freshwater)
AB: Seasonal changes in dry weights and nutrient concentrations in three aquatic grasses on the seasonally inundated Magela floodplain in northern Australia were investigated over an 18 month period. The dry weight of the aquatic grass species Pseudoraphis spinescens, Hymenachne acutigluma  and Oryza meridionalis  varied with water depth on the floodplain. Maximum dry weights occurred at the end of the wet season when water depth was decreasing. The perennial species P. spinescens  and H. acutigluma  had two growth periods and an annual productivity of 1.91  plus or minus  0.26 kg m super(-2) and 2.09  plus or minus  0.36 kg m super(-2), respectively, compared with 0.51  plus or minus  0.10 kg m super(-2) for the annual O. meridionalis . Relative to other aquatic and wetland plant species, the former two grasses have high production rates. The major nutrients nitrogen, phosphorus, sulphur, chloride, magnesium, calcium, sodium and potassium were generally present in low concentrations compared with concentrations in other plant species.
AN: 2573255

                                                                   1127 of 1521  
TI: Role of mangrove in mercury cycling and removal in the Jiulong Estuary.
AU: Lin,-Peng; Chen,-Ronghua
AF: Biol. Dep., Xiamen Univ., Xiamen 361005, People's Rep. China
SO: ACTA-OCEANOL.-SIN.-HAIYANG-XUEBAO. 1990. vol. 9, no. 4, pp. 622-624
LA: English
ER: M (Marine); B (Brackish)
AN: 2573005

                                                                   1128 of 1521  
TI: Methylation of inorganic selenium compounds by freshwater green algae, Ankistrodesums  sp., Chlorella vulgaris  and Selenastrum  sp.
AU: Oyamada,-N.; Takahashi,-G.; Ishizaki,-M.
AF: Ibaraki Hyg. Lab., 4-1 Atago-cho, Mito 310, Japan
SO: EISEI-KAGAKU. 1991. vol. 37, no. 2, pp. 83-88
LA: English
ER: F (Freshwater)
AB: Biomethylation of selenium (Se) by freshwater green algae, Ankistrodesmus  sp., Chlorella vulgaris  and Selenastrum  sp., which had been isolated from the Tone River and Lake Kasumigaura in Japan, were investigated. All of the three algae produced methylated Se compounds from the corresponding inorganic compounds. The formation of trimethylselenonium ion (TMSe) by algae reached a plateau 2-4 d after culturing and the amount of Se and TMSe was less than about 0.001% of the added Se. TMSe was also found in the algae and was in the range from 0.04 to 0.3% of total-Se accumulated in the algae. Green algae in the freshwater ecosystems might be related to methylation of Se, and biomethylation of Se by green algae is thought to be one of detoxification processes.
AN: 2572955

                                                                   1129 of 1521  
TI: Program of mineralization and cycling in marine systems: Organic geochemistry of particulates and sediments (CaBS): Technical progress report, November 15, 1988-May 14, 1989.
AU: Venkatesan,-M.I.; Kaplan,-I.R.
CA: California Univ., Los Angeles (USA)
SO: REP.-U.S.-DEP.-ENERGY. 1989. 3 pp
NT: NTIS Order No.: DE89015809/GAR. Contract FG05-85ER60338.
RN: DOE/ER/60338-7 (DOEER603387)
LA: English
ER: M (Marine)
AB: The principal objective of the current on-going project is to understand the processes involved in the cycling of organic carbon in the southern California Bight. This involves the evaluation of the relative flux of planktonic carbon to the seafloor versus the import of terrestrial carbon components and the determination of the rate of decomposition of sedimenting organic matter in the water column. These goals were achieved by the chemical characterization of sedimenting particles (from traps) as well as in the near surface sediments. The organic matter in the marine regime comprises contribution from land plants, marine productivity (plankton and bacteria) as well as anthropogenic sources. At UCLA, researchers have been focusing on the chemical characterization of selected classes of organic carbon compounds derived from these various sources to understand the vertical flux and the chemical composition of the particulate organic matter which are controlled by complex transport, transformation, degradation and remineralization processes.
AN: 2570874

                                                                   1130 of 1521  
TI: The mineralization of chitin in the sediments of the Ythan Estuary, Aberdeenshire, Scotland.
AU: Hillman,-K.; Gooday,-G.W.; Prosser,-J.I.
AF: Rowett Res. Inst., Greenburn Rd., Bucksburn, Aberdeen AB2 9SB, UK
SO: ESTUAR.-COAST.-SHELF-SCI. 1989. vol. 29, no. 6, pp. 601-612
LA: English
ER: M (Marine)
AB: Reliable methods have been developed for the quantitative estimation of chitin, chitosan and chitin deacetylase in sediment samples, as well as two methods for the estimation of chitinase in these samples. The differing substrates used in the latter two methods have produced distinct "depth profiles" for chitinase activity which suggest the presence of more than one chitinolytic system in the sediments of the Ythan estuary. Studies on the mineralization of chitin in these sediments have revealed a complex system with a number of unexpected features. The rate of chitin degradation was reduced in late summer, possibly due to the heavy seaweed growth which covers the mud flats at this time, although the potential degradative activities of the enzymes chitinase and chitin deacetylase were higher in summer than in winter.
AN: 2567946

                                                                   1131 of 1521  
TI: (Bio)geochemical reactions in aquifer material from a thermal energy storage site.
AU: Brons,-H.J.; Griffioen,-J.; Appelo,-C.A.J.; Zehnder,-A.J.B.
AF: Dep. Microbiol., Wageningen Agric. Univ., Hesselink van Suchtelenweg 4, 6703 CT Wageningen, Netherlands
SO: WATER-RES. 1991. vol. 25, no. 6, pp. 729-736
LA: English
AB: The mobilization of organic compounds and the release of CO sub(2) was studied in aquifer material from a site chosen for thermal energy storage (ETS). These processes have been measured aerobically and anaerobically within a temperature range of 4-95 degree C in sediment samples consisting of either quartz-rich coarse sand or peaty clay. At temperatures above 45 degree C organic carbon compounds, including fulvic acids, were mobilized from both sediments resulting in an increased chemical oxygen demand of the water phase. Complexation of calcium and magnesium by fulvic acids resulted in the supersaturation of the water phase with regard to calcite and dolomite and thus prevented the precipitation of these carbonates. The highest rates of CO sub(2) release were observed during the first 4 days. Aerobically, the maximum velocity for CO sub(2) formation varied between 35 and 800 (sand) or 15 and 150 (peaty clay)  mu mol CO sub(2) per gram volatile solids per day. Anaerobically, similar rates were observed, namely 25-500 (sand) and 10-110 (peaty clay)  mu mol CO sub(2) per gram volatile solids. At temperatures above 55 degree C, CO sub(2) was produced purely chemically.
AN: 2564129

                                                                   1132 of 1521  
TI: Measurement of benthic nutrient fluxes in Mediterranean shellfish farms: A methodological approach.
AU: Grenz,-C.; Plante-Cuny,-M.-R.; Plante,-R.; Alliot,-E.; Baudinet,-D.; Berland,-B.
AF: Cent. Oceanol. Marseille, Stn. Mar. Endoume, rue de la Batterie des Lions, 13007 Marseille Cedex, France
SO: OCEANOL.-ACTA. 1991. vol. 14, no. 2, pp. 195-201
LA: French
ER: M (Marine)
AB: Benthic chambers were used to investigate fluctuations in nutrient fluxes and oxygen changes when comparing 2 benthic biota. Muddy sediments located under mussel-cultivation ropes were compared with a station outside the mussels' influence. Biodeposition from the mussels results in a drastic increase in the nutrient fluxes. A standard procedure is established in order to give reliable comparisons between stations and seasons: as a rule it should include six-hour periods of incubation with sampling intervals of two hours and at least 4 benthic chambers - preferably six - at each station.
AN: 2559440

                                                                   1133 of 1521  
TI: Sediment interactions with submersed macrophyte growth and community dynamics.
AU: Barko,-J.W.; Gunnison,-D.; Carpenter,-S.R.
AF: Environ. Lab., Waterw. Exp. Stn., Vicksburg, MS 39180-6199, USA
SO: AQUAT.-BOT. 1991. vol. 41, no. 1-3, pp. 41-65
NT: Special issue: Ecology of submersed aquatic macrophytes.
LA: English
ER: F (Freshwater)
AB: The authors review and synthesize information available in the literature on sediment interactions with submersed macrophyte growth and community dynamics. Sources of particular nutrients for uptake by submersed macrophytes are critically evaluated. Sediment physical and chemical properties are considered as a product of macrophyte growth as well as potential delimiters of growth. Aspects of macrophyte nutrition that influence littoral nutrient dynamics and macrophyte community composition are highlighted, with attention to factors affecting sediment nutrient availability. Interactive effects of sediment nutrient depletion, sedimentation, bioturbation, and microbial activity on macrophyte growth are emphasized. Major linkages and feedbacks between aquatic macrophytes and sediment properties are considered in terms of elemental exchanges and responses at the ecosystem level. Changes in macrophyte community composition during lake aging, or over relatively shorter time periods, are suggested to occur partially in response to altered sediment properties.
AN: 2559269

                                                                   1134 of 1521  
TI: Galerucella nymphaeae  (Col., Chrysomelidae) grazing increases Nuphar  leaf production and affects carbon and nitrogen dynamics in ponds.
AU: Setaelae,-H.; Maekelae,-I.
AF: Univ. Jyvaeskylae, Dep. Biol., SF-40100, Jyvaeskylae, Finland
SO: OECOLOGIA. 1991. vol. 86, no. 2, pp. 170-176
LA: English
ER: F (Freshwater)
AB: The grazing effects of the waterlily beetle Galerucella nymphaeae  on Nuphar lutea  stands were studied in 3 ponds in central Finland. Production of floating leaves of N. lutea  and growth in the G. nymphaeae  population were investigated in the ponds and bioenergetics of the beetle larvae in the laboratory. Combination of field and laboratory data enabled estimation of the effect of the beetle on the production of floating leaves of N. lutea  and the consequences of grazing for the input of detritus from Nuphar  into the ponds. Adults and larvae of G. nymphaeae  consumed 3.0-6.1% of the net annual floating leaf production during the growing period. In addition to consumption losses, feeding accelerated the degradation rate of the leaves. This was associated with an increased flow of detrital material of Nuphar  origin, and also with increased production of floating leaves in the ponds.
AN: 2553483

                                                                   1135 of 1521  
TI: Annual material processing by a salt marsh-estuarine basin in South Carolina, USA.
AU: Dame,-R.F.; Spurrier,-J.D.; Williiams,-T.M.; Kjerfve,-B.; Zingmark,-R.G.; Wolaver,-T.G.; Chrzanowski,-T.H.; McKellar,-H.N.; Vernberg,-F.J.
AF: Dep. Mar. Sci., Coast. Carolina Coll., Conway, SC 29526, USA
SO: MAR.-ECOL.-PROG.-SER. 1991. vol. 72, no. 1-2, pp. 153-166
NT: Bibliogr.: 71 ref.
LA: English
ER: M (Marine)
AB: A synthesis of a comprehensive annual study of material processing in the Bly Creek marsh-estuarine basin is described. The project design provides statistical estimates of material fluxes for the water column, salt marsh, and oyster reef subsystems. Material processing by the Bly Creek marsh-estuarine basin is constituent- and subsystem-specific. Inflows of material via rain, streamwater, and groundwater are small and relatively unimportant compared to tidal fluxes. The salt marsh dominates the basin in aerial extent and in terms of net material fluxes. Most constituents exhibit significant net annual import to the salt marsh. Only DON is exported from the marsh and from the basin at significant levels. The salt marsh appears to recycle most of the nitrogen and phosphorus needed for marsh grass primary production. Sufficient inorganic particulate material is imported to allow the salt marsh to maintain its elevation with respect to ongoing sea-level rise.
AN: 2551723

                                                                   1136 of 1521  
TI: Nutrients and chlorophyll at the interface of a watershed and an estuary.
AU: Jordan,-T.E.; Correll,-D.L.; Miklas,-J.; Weller,-D.E.
AF: Smithsonian Environ. Res. Cent., P.O. Box 28, Edgewater, MD 21037-0028, USA
SO: LIMNOL.-OCEANOGR. 1991. vol. 36, no. 2, pp. 251-267
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: The authors investigated the fates of nutrients entering the Rhode River estuary from its watershed and from atmospheric deposition. Production or consumption of materials in the upper estuary was calculated from a mixing model with chloride as a conservative tracer. The upper estuary produced chlorophyll and dissolved PO sub(4) super(3) super(-) (DPO sub(4) super(3) super(-)) but consumed particulate PO sub(4) super(3) super(-) (PPO sub(4) super(3) super(-)), total inorganic N, dissolved organic N, and particulate organic C. These net fluxes were influenced more by shallow, open-water areas than by the tidal marshes which cover two-thirds of the area of the upper estuary. Ratios of chlorophyll to organic C, N, and P suggest that most of the suspended particulate organic matter in the upper estuary was produced by phytoplankton rather than derived from watershed inputs. The consumption of nitrate due to phytoplankton production and the production of DPO sub(4) super(3) super(-) due to release from particulate P after deposition in sediments resulted in low inorganic N:P ratios, contrasting sharply with the lower estuary and adjacent Chesapeake Bay.
AN: 2551032

                                                                   1137 of 1521  
TI: Study of carbon dioxide (CO sub(2)) problems through marine science.
AU: Honda,-M.
AF: Mar. Res. and Dev. Dep., JAMSTEC, 2-15 Natsushima-cho, Yokosuka 237, Japan
SO: REP.-JAPAN-MAR.-SCI.-TECHNOL.-CENT. 1990. no. 24, pp. 189-222
LA: Japanese
ER: M (Marine)
AB: In order to grasp the trend of carbon dioxide (CO sub(2)) increase, which causes worldwide climatic changes, and to predict the global environment in the future, it is important to understand the carbon budget and carbon cycle on the earth exactly. As the ocean is 300 times in mass and 1100 times in thermal capacity bigger than the atmosphere, it is necessary to understand the process of the carbon cycle in the ocean and to know how the ocean reacts to the CO sub(2) increase in the atmosphere. For this purpose, the study of CO sub(2) exchange through the sea surface and interaction between atmosphere, ocean, and biomass must be done accurately. Especially it is needed to carry out the observations under special conditions, when it is very difficult to do with using ordinary research vessels, in the characteristic area (arctic zone, equatorial zone, or coastal zone etc.). Coral reef is one of these characteristic areas, because the production is so high and CO sub(2) is removed through the calcification process by coral. This reviews papers discussing the carbon cycle in the ocean and considers the ability of fixing CO sub(2) by coral reef.
AN: 2546404

                                                                   1138 of 1521  
TI: Burrowing beetles of the genus Bledius  (Staphylinidae) as agents of bioturbation in the emergent areas and shores of an athalassic inland lake (Fuente de Piedra, south of Spain).
AU: Garcia,-C.M.; Niell,-F.X.
AF: Dep. Ecol., Fac. Cienc., Campus Univ. Teatinos, 29071-Malaga, Spain
SO: HYDROBIOLOGIA. 1991. vol. 215, no. 2, pp. 163-173
LA: English
ER: B (Brackish)
AB: Bledius (Elbidus) bicornis  and B. (Eucerotobledius) furcatus  (Coleoptera: Staphylinidae) are the most important burrowing species in the emergent areas and shores in the athalassic lake of Fuente de Piedra (Malaga, S. of Spain). A first estimate of the importance of these organisms in this system is presented. These insects kick out sediment during their burrowing activity, which accumulates on the surface near the burrows as tumuli which can be easily eroded. The lake perimeter (17 km) is densely colonized (usual densities from 1700 to 2500 ind/m super(2)). The amount of granulated material that can be potentially kicked out was 46.22 g dry wt/m super(2)/day. At the same time, the material that constitutes the tumuli shows different characteristics from the compact ground below the surface. Thus, it is relatively enriched with organic matter (6.15 g per square meter), soluble phosphate (406.5  mu g/m super(2)) and ammonium (4856  mu g/m super(2)), whereas it lacks nitrate.
AN: 2546105

                                                                   1139 of 1521  
TI: Algal control of elemental sedimentary fluxes in Lake Constance.
AU: Stabel,-H.-H.
AF: Limnol. Inst., Univ. Konstanz, Mainaustr. 212, D-7750 Konstanz, FRG
CO: 23. Congress in New Zealand, (Hamilton (New Zealand)), 8 Feb 1987
SO: CONGRESS-IN-NEW-ZEALAND-1987.-PROCEEDINGS. Sladecek,-V.-ed. 1988. vol. 23, no. 2 pp. 700-706
ST: VERH.-INT.-VER.-THEOR.-ANGEW.-LIMNOL.-PROC.-INT.-ASSOC.-THEOR.-APPL.-LIMNOL.-TRAV.-ASSOC.-INT.-LIMNOL.-THEOR.-APPL. vol. 23, no. 2
LA: English
ER: F (Freshwater)
AB: It was the aim of this investigation to relate the main settling phases of predominant elements to the seasonality in the development of specific phytoplankton species. In Lake Constance the settling material is dominated by calcium carbonate, followed in order of significance by diatomaceous silica and organic matter (i.e. algae and organic debris). The seasonal fluctuations in the sedimentation rates of organic carbon were not related to seasonal changes in the phytoplankton primary productivity.
AN: 2546054

                                                                   1140 of 1521  
TI: Chemical characterization of polysaccharide from the slime layer of the cyanobacterium Microcystis flos-aquae  C3-40.
AU: Plude,-J.L.; Parker,-D.L.; Schommer,-O.J.; Timmerman,-R.J.; Hagstrom,-S.A.; Joers,-J.M.; Hnasko,-R.
AF: Dep. Biol., Univ. Wisconsin, Oshkosh, WI 54901, USA
SO: APPL.-ENVIRON.-MICROBIOL. 1991. vol. 57, no. 6, pp. 1696-1700
LA: English
ER: F (Freshwater)
AB: Macromolecular material from the slime layer of the cyanobacterium Microcystis flos-aquae  C3-40 was defined as material that adhered to cells during centrifugation in growth medium but was dislodged by washing with deionized water and retained within dialysis tubing with a molecular-weight cutoff of 3,500. At each step of this isolation procedure, the slime was observed microscopically. Cells in the centrifugal pellet were surrounded by large amounts of slime that excluded negative stain, whereas cells that had been washed with water lacked visible slime. Two independently isolated lots of slime contained no detectable protein (< 1%, wt/wt) and consisted predominantly of anthrone-reacting polysaccharide. Sugars in a hydrolysate of slime polysaccharide were derivatized with trimethylsilylimidazole and examined by gas chromatography-mass spectrometry. The composition of the slime polysaccharide was 1.5% (wt/wt) galactose, 2.0% glucose, 3.0% xylose, 5.0% mannose, 5.5% rhamnose, and 83% galacturonic acid.
AN: 2546013

                                                                   1141 of 1521  
TI: Size-fractionated uptake and regeneration of ammonium and phosphate in a tropical lake.
AU: Fisher,-T.R.; Doyle,-R.D.; Peele,-E.R.
AF: Horn Point Lab., Univ. Maryland, CEES, Cambridge, MD 21613, USA
CO: 23. Congress in New Zealand, (Hamilton (New Zealand)), 8 Feb 1987
SO: CONGRESS-IN-NEW-ZEALAND-1987.-PROCEEDINGS. Sladecek,-V.-ed. 1988. vol. 23, no. 2 pp. 637-641
ST: VERH.-INT.-VER.-THEOR.-ANGEW.-LIMNOL.-PROC.-INT.-ASSOC.-THEOR.-APPL.-LIMNOL.-TRAV.-ASSOC.-INT.-LIMNOL.-THEOR.-APPL. vol. 23, no. 2
LA: English
ER: F (Freshwater)
AB: The activity of planktonic size fractions in a tropical lake near the Amazon River were examined as part of a general investigation of the biogeochemistry of floodplains. Size fractioning of the plankton was used to attempt to separate different groups of organisms and to measure the rates of N and P cycling within each size fraction. Particularly in focus was the role of bacterioplankton in the uptake and regeneration of N and P. The data indicated that a large fraction of N and P cycling in Lake Calado occurs in the < 3  mu m, largely heterotrophic, size fraction of the plankton. Greater than 1/2 of the P uptake and 10-50% of the ammonium uptake appears to be due to heterotrophic bacteria-sized organisms, and  approximately equals  1/2 of the ammonium regeneration appears to occur in the same fraction, probably by different organisms of approximately the same size.
AN: 2545894

                                                                   1142 of 1521  
TI: How plankton change the climate (JGOFS).
AU: Williamson,-P.; Gribbin,-J.
AF: Plymouth Mar. Lab., Citadel Hill, Plymouth PL1 2PB, UK
SO: NEW-SCI. 1991. vol. 129, no. 1760, pp. 48-52
LA: English
ER: M (Marine)
AB: The oceans store about 50 times more carbon than the air, and, each year, oceans and atmosphere exchange around 15 times as much carbon dioxide as human activities produce. To predict how carbon dioxide will build up in future, and, in turn, understand changes in the climate, we need to understand how the ocean carbon cycle works. This is the aim of the Joint Global Ocean Flux Study (JGOFS), a 10-year programme that forms the main project in the International Geosphere Biosphere Programme, which investigates environmental change on a world scale. JGOFS oceanographers, biologists and chemists investigated the North Atlantic in 1989 to find out more about how and why plankton grow, what then happens to the carbon that they fix in their tissue, and what effect these organisms have on the exchange of carbon dioxide between air and sea. One target was to find out exactly what happens in the spring, when vast numbers of phytoplankton "bloom" across the oceans over a few weeks. Researchers were particularly interested in measuring the partial pressure of carbon dioxide at the surface of the sea.
AN: 2544964

                                                                   1143 of 1521  
TI: Role of bacteria in the North Sea ecosystem.
AU: Billen,-G.; Joiris,-C.; Meyer-Reil,-L.; Lindeboom,-H.
AF: Univ. Brussels, Campus La Plaine, CP 221, 1050 Brussels, Belgium
CO: Int. Symp. on the Ecology of the North Sea, (Netherlands), 18-22 May 1988
SO: NETH.-J.-SEA-RES. 1990. vol. 26, no. 2-4, pp. 265-293
LA: English
ER: M (Marine)
AB: For about 15 years methods available to assess the role of bacteria in organic matter cycling of aquatic ecosystems have been considerably improved. Their application to the North Sea deeply modified the vision of the ecological structure of this ecosystem which prevailed in the early seventies, as summarized e.g. by Steele (1974). A critical examination of the methodology utilized for measuring standing stock and activities of bacteria in the water column and the sediments of the North Sea is presented and the results of these measurements summarized.
AN: 2542454

                                                                   1144 of 1521  
TI: Biogeochemical processes governing exposure and uptake of organic pollutant compounds in aquatic organisms.
AU: Farrington,-J.W.
AF: Environ. Sci. Program, Univ. Massachusetts, Harbor Campus, Boston, MA 02125, USA
CO: Symp. on Chemically Contaminated Aquatic Food Resources and Human Cancer Risk, Research Triangle Park, NC (USA), 29-30 Sep 1988
SO: ENVIRON.-HEALTH-PERSPECT. 1991. vol. 90, pp. 75-84
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: This paper reviews current knowledge of biogeochemical cycles of pollutant organic chemicals in aquatic ecosystems with a focus on coastal ecosystems. There is a bias toward discussing chemical and geochemical aspects of biogeochemical cycles and an emphasis on hydrophobic organic compounds such as polynuclear aromatic hydrocarbons, polychlorinated biphenyls, and chlorinated organic compounds used as pesticides. The complexity of mixtures of pollutant organic compounds, their various modes of entering ecosystems, and their physical chemical forms are discussed. Important factors that influence bioavailability and disposition (e.g., organism-water partitioning, uptake via food, food web transfer) are reviewed. These factors include solubilities of chemicals; partitioning of chemicals between solid surfaces, colloids, and soluble phases; variables rates of sorption, desorption; and physiological status of organism. It appears that more emphasis on considering food as a source of uptake and bioaccumulation is important in benthic and epibenthic ecosystems when sediment-associated pollutants are a significant source of input to an aquatic ecosystem. Progress with mathematical models for exposure and uptake of contaminant chemicals is discussed briefly.
AN: 2542415

                                                                   1145 of 1521  
TI: Selectivity in metal uptake by stationary phase microbial populations.
AU: Premuzic,-E.T.; Lin,-Mow; Zhu,-Hong-Li; Gremme,-A.M.
AF: Dep. Appl. Sci., Brookhaven Natl. Lab., Upton, NY 11973, USA
SO: ARCH.-ENVIRON.-CONTAM.-TOXICOL. 1991. vol. 20, no. 2, pp. 234-240
LA: English
ER: F (Freshwater)
AB: In the interaction of metals with the cellular biomass of microorganisms in aqueous solutions, cell wall constituents have been implicated as being responsible for metal binding. Chemical and structural characteristics of cell membranes vary with species and should therefore influence the selective capacity for uptake of different metals by different microorganisms, and thus also influence the behavior of metallic species in the environment. While the rates of uptake of metals by microorganisms have been studied extensively, the comparative capacity for selective uptake of metals by different species of microorganisms under identical experimental conditions has not been studied systematically. To test for this property, cellular biomass derived from eight representative microorganisms has been allowed to interact under similar experimental conditions with acidic solutions of seven heavy metals. The results of these studies show that, in addition to metal selectivity, there is also a species dependent differentiation in the uptake capacity.
AN: 2541985

                                                                   1146 of 1521  
TI: Top predators in the Southern Ocean: A major leak in the biological carbon pump.
AU: Huntley,-M.E.; Lopez,-M.D.G.; Karl,-D.M.
AF: Scripps Inst. Oceanogr., Univ. California at San Diego, La Jolla, CA 92093, USA
SO: SCIENCE-WASH.. 1991. vol. 253, no. 5015, pp. 64-66
LA: English
ER: M (Marine)
AB: Primary productivity in the Southern Ocean is approximately 3.5 gigatons of carbon per year, which accounts for nearly 15 percent of the global total. The presence of high concentrations of nitrate in Antarctic waters suggests that it might be possible to increase primary production significantly and thereby alleviate the net accumulation of atmospheric carbon dioxide. An analysis of the food web for these waters implies that the Southern Ocean may be remarkably inefficient as a carbon sink. This inefficiency is caused by the large flux of carbon respired to the atmosphere by air-breathing birds and mammals, dominant predators in the unusually simple food web of Antarctic waters. These top predators may transfer into the atmosphere as much as 20 to 25 percent of photosynthetically fixed carbon.
AN: 2541843

                                                                   1147 of 1521  
TI: Distribution of dissolved iron in sediment pore waters at submillimetre resolution.
AU: Davison,-W.; Grime,-G.W.; Morgan,-J.A.W.; Clarke,-K.
AF: Inst. Environ. and Biol. Sci., Univ. Lancaster, Lancaster LA1 4YQ, UK
SO: NATURE. 1991. vol. 352, no. 6333, pp. 323-325
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: Much effort has been directed at measuring concentration gradients at the sediment/water interface of aquatic systems, where the biogeochemical cycling of natural and pollutant species is particularly active. Precise measurements of oxygen gradients using microelectrodes and estimates from independently determined fluxes suggest that concentration gradients in this region often extend only to depths of  similar to 1 mm, much less than the resolution ( similar to 1 centimetre) of conventional techniques. We have developed a new method for measuring pore-water composition in which diffusive equilibrium is established rapidly (within minutes) in a thin film of gel inserted in the sediment. On removal, the dissolved components are fixed, allowing chemical measurements to be made at high spatial resolution (<1 mm) on a stable solid phase. Using MeV-proton-induced X-ray emission (PIXE) to analyse the dried gel, we have measured iron concentrations in lacustrine pore waters at submillimeter resolution, revealing steep concentration gradients and sub-surface maxima consistent with a hypothesis of localized, reductive dissolution of fresh material.
AN: 2540026

                                                                   1148 of 1521  
TI: Methylated sulfur compounds in microbial mats: In situ concentrations and metabolism by a colorless sulfur bacterium.
AU: Visscher,-P.T.; Quist,-P.; van-Gemerden,-H.
AF: Dep. Microbiol., Univ. Groningen, Kerklaan 30, 9751 NN Haren, Netherlands
SO: APPL.-ENVIRON.-MICROBIOL. 1991. vol. 57, no. 6, pp. 1758-1763
LA: English
ER: M (Marine)
AB: The concentrations of the volatile organic sulfur compounds methanethiol, dimethyl disulfide, and dimethyl sulfide (DMS) and the viable population capable of DMS utilization in laminated microbial ecosystems were evaluated. Significant levels of DMS and dimethyl disulfide (maximum concentrations of 220 and 24 nmol cm super(3)/sediment, respectively) could be detected only at the top 20 mm of the microbial mat, whereas methanethiol was found only at depth horizons from 20 to 50 mm (maximum concentration of 42 nmol cm super(3)/sediment). DMS concentrations in the surface layer doubled after cold hydrolysis of its precursor, dimethyl-sulfoniopropionate. Most-probable-number counts revealed 2.2 x 10 super(5) cells cm super(3)/sediment, in the 0- to 5-mm depth horizon, capable of growth on DMS as the sole source of energy. An obligately chemolithoautotrophic bacillus designated strain T5 was isolated from the top layer of the marine sediment. Continuous culture studies in which DMS was the growth-limiting substrate revealed a maximum specific growth rate of 0.10/h and a saturation constant of 90  mu mol/l for aerobic growth on this substrate.
AN: 2537720

                                                                   1149 of 1521  
TI: Lead removal from contaminated water by a mixed microbial ecosystem.
AU: Bender,-J.A.; Archibold,-E.R.; Ibeanusi,-V.; Gould,-J.P.
AF: Dep. Biol., Morehouse Coll., Atlanta, GA 30314, USA
CA: International Assoc. on Water Pollution Research and Control, London (UK)
CO: 14. Bienn. Conf. of the IAWPRC: Water Pollution Research and Control, Brighton (UK), 18-21 Jul 1988
SO: WATER-POLLUTION-RESEARCH-AND-CONTROL,-BRIGHTON,-PART-5. Lijklema,-L.;et-al.-eds. 1989. vol. 21, no. 12 pp. 1661-1664
ST: WATER-SCI.-TECHNOL. vol. 21, no. 12
LA: English
ER: F (Freshwater)
AB: This study explored the advantages of using an integrated ecosystem for the uptake of lead and examined some of the possible mechanisms for the transfer of the metal through the system with eventual binding in the microbial biomass. Strategies were applied to (1) stimulate enhanced production of biomass and consequent lead recovery by simple enrichments of the microbial environment, and (2) increase the microbial tolerance and lead uptake capacity by adaptation of the component species. The microbial ecosystem employed was one which arose spontaneously after pond enrichment with silaged grass clippings and moved through a predictable microbial succession. Ecosystem processes and microbial relationships resulted in the mobilization of metal in the soil bed and water column with ultimate deposition in the surface biomass. The stable silage-microbe biomass, floating at the top of the pond, bound the metal for extended periods of time.
AN: 2535280

                                                                   1150 of 1521  
TI: Depletion of barium and radium-226 in Black Sea surface waters over the past thirty years.
AU: Falkner,-K.K.; O'-Neill,-D.J.; Todd,-J.F.; Moore,-W.S.; Edmond,-J.M.
AF: Groupe Rech. Geod. Spat., Cent. Natl. Etud. Spat., 18 Ave. Edouard Belin, 31055 Toulouse Cedex, France
SO: NATURE. 1991. vol. 350, no. 6318, pp. 491-494
LA: English
ER: M (Marine)
AB: The nearly landlocked waters of the Black Sea support a valuable fishery, but are also particularly vulnerable to anthropogenic disturbance. Here we use dissolved barium and radium-226 as tracers, to investigate the biogeochemical health of the sea. Both elements are brought to surface waters by vertical mixing of deeper, enriched waters, and by rivers; these inputs should ordinarily be balanced by outflow of surface waters at the Bosphorus, and by biologically mediated removal of  super(226)Ra-bearing barite. We show, however, that surface-water inventories have been substantially depleted over the past few decades. Observations suggest that steady-state cycling of these elements has been perturbed by increased primary productivity, presumably fuelled by nutrients from industry and agricultural runoff, and to a lesser extent by decreased fluvial sediment loads owing to extensive impoundment of rivers in the region.
AN: 2535226

                                                                   1151 of 1521  
TI: The mechanism controlling plant nutrient concentrations in the northern Adriatic Sea.
AU: Gilmartin,-M.; Degobbis,-D.; Revelante,-N.; Smodlaka,-N.
AF: Dep. Zool., Univ. Maine, Orono, ME 04469, USA
SO: INT.-REV.-GESAMT.-HYDROBIOL. 1990. vol. 75, no. 4, pp. 425-445
NT: Bibliogr.: 77 ref.
LA: English
ER: M (Marine)
AB: A 20 year data set for the northern Adriatic was analyzed and the factors establishing the nutrient environment identified. Concentrations ranged widely (TIN 0.0-78, PO sub(2) 0.01-1.1, and SiO sub(4) 0.0-59 mmol/m super(3)). In early winter remineralization increased concentrations. Characteristic winter, late spring and fall phytoplankton blooms alternately decreased and increased concentrations, as modified by river input. In summer nutrients were minimal under a semi-closed circulation pattern and high vertical stability, due to closely coupled nitrogen and phosphorus assimilation-regeneration processes and biogenic silica sedimentation. "New" primary production supported mainly by river input of "new" nutrients approximated "regenerated" primary production supported by regenerated nutrients, making the ecosystem especially sensitive to eutrophication pressure from anthropogenic increases in the Po River nutrient load.
AN: 2534558

                                                                   1152 of 1521  
TI: Anaerobic microbial biogeochemistry in sediments from two basins in the Gulf of Maine: Evidence for iron and manganese reduction.
AU: Hines,-M.E.; Bazylinski,-D.A.; Tugel,-J.B.; Lyons,-W.B.
AF: Inst. Stud. Earth, Oceans and Space, Univ. New Hampshire, Durham, NH 03824, USA
SO: ESTUAR.-COAST.-SHELF-SCI. 1991. vol. 32, no. 4, pp. 313-324
LA: English
ER: M (Marine)
AB: Rates of sulphate reduction, denitrification and glucose turnover were determined in surface sediments collected from Jeffreys and Wilkinson Basins in the Gulf of Maine. These data were compared to porewater profiles of iron and manganese. Three distinct anaerobic biogeochemical situations were evident: sulphate reduction was dominant and active near the sediment-water interface (deeper portions of Jeffreys Basin); denitrification was active in the upper few centimetres and was underlain by rapid sulphate reduction (slope of Jeffreys Basin); denitrification was dominant (Wilkinson Basin). An apparent iron and manganese reduction region was evident in all cores. Since glucose turnover was active and both denitrification and sulphate reduction were low within this metal reduction zone it is possible that microbial metal reduction is a significant process within the basin sediments.
AN: 2532355

                                                                   1153 of 1521  
TI: Pressure tolerance of oceanic flagellates: Implications for remineralization of organic matter.
AU: Turley,-C.M.; Carstens,-M.
AF: Plymouth Mar. Lab., Citadel Hill, Plymouth PL1 2PB, UK
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1991. vol. 38, no. 4A, pp. 403-413
LA: English
ER: M (Marine)
AB: Active growth of the total mixed flagellate population, comprising three species isolated from the euphotic zone in the northeast Atlantic, occurred up to pressures of 200 atm. (equivalent to 2000 m water depth). At pressures greater than 200 atm. there was a steady decrease in total flagellate numbers. These results could be misinterpreted to conclude that pressures greater than 200 atm. have a deleterious effect on flagellates. When the effects of pressure were investigated at the species level a different picture emerges. One species, Paraphysomonas butcheri , was weakly barotolerant reproducing at up to 100 atm. Another, Bodo curvifilus , had a wide barotolerance dividing at up to pressures of 300 atm., while the third, a Cercomonas -like species, only grew at pressures of 300 atm. and over. Such results indicate the importance of investigations at the species level as well as population level.
AN: 2531044

                                                                   1154 of 1521  
TI: Ice-core record of oceanic emissions of dimethylsulphide during the last climate cycle.
AU: Legrand,-M.; Feniet-Saigne,-C.; Saltzman,-E.S.; Germain,-C.; Barkov,-N.I.; Petrov,-V.N.
AF: Lab. Glaciol. et Geophys. Environ., B.P. 96, 38402 St. Martin d'Heres, Cedex, France
SO: NATURE. 1991. vol. 350, no. 6314, pp. 144-146
LA: English
ER: M (Marine)
AB: The Vostok ice core in Antarctica has provided one of the longest climate records, enabling the stable-isotope, major-ion and gas composition of the atmosphere to be reconstructed over many thousands of years. Depth profiles along this core of methanesulphonate and non-seasalt sulphate (produced by the atmospheric oxidation of dimethylsulphide), provide the first historical record of biogenic sulphur emissions from the Southern Hemisphere oceans over a complete glacial-interglacial cycle (160 kyr), and indicate increased oceanic emissions of dimethylsulphide during the later stages of the glacial period, compared with the present day. The observed glacial-interglacial variations in methanesulphonate and non-seasalt sulphate confirm that the ocean-atmosphere sulphur cycle is extremely sensitive to climate change.
AN: 2528220

                                                                   1155 of 1521  
TI: Particle (plankton) size structure across the Azores Front (Joint Global Ocean Flux Study North Atlantic bloom experiment).
AU: Kahru,-M.; Nommann,-S.; Zeitzschel,-B.
AF: Inst. Ecol. and Mar. Res., Tallinn, Estonia
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1991. vol. 96, no. C4, pp. 7083-7088
LA: English
ER: M (Marine)
AB: The horizontal distributions of particle size spectrum and chlorophyll a concentration across the northern edge of the North Atlantic Subtropical Gyre along 21 degree W were studied as part of the Joint Global Ocean Flux Study North Atlantic Bloom Experiment in March-April, 1989. An abrupt change in the particle size spectrum at 32 degree 40'N was located within the broad thermohaline front between the central gyre water in the south and the Azores Current in the north. Whereas the small particulate fraction (1-10  mu m) and chlorophyll a concentration were similar (within a factor of 2), the abundance of the "diatom" size fraction (28-72  mu m) showed a drastic increase by more than an order of magnitude in the Azores Current. The diatom fraction seemed to contribute little to the chlorophyll pool, indicating a postbloom condition.
AN: 2528121

                                                                   1156 of 1521  
TI: Sulfate reduction in marine sediments from the Baltic Sea-North Sea transition.
AU: Joergensen,-B.B.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, DK-8000 Aarhus C, Denmark
SO: OPHELIA. 1989. vol. 31, no. 1, pp. 1-15
LA: English
ER: M (Marine)
AB: The spatial distribution and intensity of sulfate reduction was studied in the upper 0-15 cm of coastal sediments by radiotracer technique. The study area extended from the eastern North Sea through Skagerrak and Kattegat into the Belt Sea at the entrance to the Baltic Sea. The 27 sampling stations ranged from pure sand to clayey mud with organic contents from 0.2 to 13% dry weight. Water depths ranged from 7 to 200 m. Depth-integrated sulfate reduction rates were mostly 1-5 mmol/m super(2)/d in the Skagerrak-Kattegat-Belt Sea area. Lowest rates, 0.08-1.0 mmol/m super(2)/d, were encountered in low-organic sands from exposed parts of the North Sea. Extremely high rates, 17-30 mmol/m super(2)/d, were found in the Helgoland Bight, SE North Sea, near the mouth of the Elbe River. Intensive sulfate reduction was associated with areas of fine-grained sediment and with high deposition rates of organic detritus. The degree of pyritization correlated positively to sulfate reduction rates (r = 0.63) and to FeS concentrations (r = 0.70). In deeper stations of northern Kattegat and Skagerrak, < 5% of the iron occurred as pyrite.
AN: 2527794

                                                                   1157 of 1521  
TI: Oxygen uptake, bacterial distribution, and carbon-nitrogen-sulfur cycling in sediments from the Baltic Sea-North Sea transition.
AU: Joergensen,-B.B.; Revsbech,-N.P.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, DK-8000 Aarhus C, Denmark
SO: OPHELIA. 1989. vol. 31, no. 1, pp. 29-49
LA: English
ER: M (Marine)
AB: Chemical zonations and bacterial distribution and metabolism were studied at fourteen sediment stations in the Belt Sea, the Kattegat, and the Skagerrak. Water depths were 14-200 m and sediment types ranged from clay and silt to fine sand. The oxic zone as determined by microelectrodes was only 1.3-5.6 mm deep while the oxidized zone (Eh > + 100 mV) was one to several cm. Roughly 90% of the oxidized layer was thus anoxic. A pH minimum occurred just below the oxic-anoxic interface. Subsurface nitrate maxima extended to depths of 1.5-5 cm. Total bacterial densities at the sediment surface were 0.25-10.0 x 10 super(8)/cm super(3). Bacterial distributions showed no correlation with the measured rates of aerobic or anaerobic metabolism. Acetate turnover rates highly exceeded sulfate reduction, probably due to problems of identifying the bacterially available acetate pool and its specific radioactivity. A rough carbon budget for the Belt Sea and Kattegat areas showed that 44% of the total primary production in the water column reached the sea floor by sedimentation.
AN: 2527386

                                                                   1158 of 1521  
TI: Formation of methylmercaptan and dimethylsulfide from methoxylated aromatic compounds in anoxic marine and fresh water sediments.
AU: Finster,-K.; King,-G.M.; Bak,-F.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, DK-8000 Aarhus C, Denmark
SO: FEMS-MICROBIOL.-ECOL. 1990. vol. 74, no. 4, pp. 295-302
LA: English
ER: M (Marine); F (Freshwater)
AB: Anaerobic formation of dimethylsulfide (DMS) and methylmercaptan (MSH) in anoxic sulfide-containing slurries from marine and fresh water sediments was stimulated by addition of syringate (4-hydroxy,3,5,-dimethoxybenzoate) and 3,4,5-trimethoxybenzoate. The release of DMS and MSH occurred during the consumption of the aromatic monomers and ceased after their depletion. This study demonstrates a previously unknown microbial process by which DMS and MSH are formed during anaerobic decomposition of methoxylated aromatic compounds in marine and freshwater sediments.
AN: 2520708

                                                                   1159 of 1521  
TI: A rate for the scavenging of fine particles by macroaggregates in a deep estuary.
AU: Lavelle,-J.W.; Cudaback,-C.N.; Paulson,-A.J.; Murray,-J.W.
AF: NOAA/Pac. Mar. Environ. Lab., Seattle, WA 98195, USA
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1991. vol. 96, no. C1, pp. 783-790
LA: English
ER: M (Marine)
AB:  super(234)Th activity profiles in Puget Sound have been studied using a model that incorporates reversible exchanges between dissolved, fine particulate, and macroaggregate Th reservoirs. Macroaggregate settling is made responsible for the downward flux of Th and the vertical gradients of activity in measured profiles. Least squares fits of model to data yield rates/time scales for the exchange processes involved. Rates of sorption and remobilization characterizing the exchange between dissolved and fine-particulate forms of the isotope cannot be individually identified from these data, but acceptable model values include those measured in the laboratory. Rates of sorption that depend on particulate concentrations which increase to the seafloor result in profiles of dissolved Th having above-bottom maxima. Based on inferred exchange rates, the residence time for fine particles introduced at the surface of this deep ( similar to 200 m) estuary is estimated to be 11-16 days when w sub(s) = 100 m/d.
AN: 2519150

                                                                   1160 of 1521  
TI: Iron availability, nitrate uptake, and exportable new production in the Subarctic Pacific.
AU: Banse,-K.
AF: Sch. Oceanogr., Univ. Washington, Seattle, WA 98195, USA
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1991. vol. 96, no. C1, pp. 741-748
LA: English
ER: M (Marine)
AB: Iron-limitation of phytoplankton was recently postulated as the reason for the high nutrient (N, P) but low phytoplankton concentrations offshore in the subarctic and equatorial Pacific, as well as the circumpolar southern ocean. This hypothesis led to the suggestion that small additions of iron to those large areas might be a way of removing significant amounts of anthropogenic CO sub(2) from the atmosphere. Rates of nitrate uptake in bioassays from the open Gulf of Alaska by Martin et al. (1989) are reinterpreted. During the exponential phase of phytoplankton growth, iron addition affected the rate of nitrate uptake significantly at only one of the 3 stations. It is suggested that in the field, grazing normally seems to prevent the phytoplankton from reaching concentrations that reduce the iron (and nitrate) to levels that depress division rates drastically. Although nitrate uptake may be equated with new production, the export to depth of new organic material (and hence of CO sub(2)) is not predictable from assays in small (liter) containers, especially so because the role of the large grazers on the size composition of the phytoplankton and the production of large sinking particle is not evaluated.
AN: 2518477

                                                                   1161 of 1521  
TI: Ammonium recycling versus denitrification in Chesapeake Bay sediments.
AU: Kemp,-W.M.; Sampou,-P.; Caffrey,-J.; Mayer,-M.; Henriksen,-K.; Boynton,-W.R.
AF: Horn Point Environ. Lab., Univ. Maryland, P.O. Box 775, Cambridge, MD 21613, USA
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 7, pp. 1545-1563
LA: English
ER: M (Marine); B (Brackish)
AB: Contemporaneous measurements are reported for nitrification, denitrification, and net sediment-water fluxes of NH sub(4) super(+) and NO sub(3) super(-) in the mesohaline region of Chesapeake Bay. Seasonal cycles over a 2-yr period were characterized by a midsummer maximum in NH sub(4) super(+) efflux to the overlying water and a May peak in NO sub(3) super(-) removal from water by sediments. Coherent temporal patterns for nitrification and denitrification were observed, with relatively high values in spring and fall and virtual elimination of both processes in summer. Indirect measurements indicate that nitrification was limited by the shallow O sub(2) penetration (<1 mm) here compared to reports for other marine sediments (2-6 mm). In addition, a strong positive correlation between the two processes suggested that denitrification was generally controlled by nitrification. Comparisons of NO sub(3) super(-) fluxes and net nitrification rates (nitrification minus NO sub(3) super(-) reduction to NH sub(4) super(+)) revealed that measurements of denitrification with the acetylene block method systematically underestimated actual rates.
AN: 2510639

                                                                   1162 of 1521  
TI: Impact of eutrophication on the silicate cycle of man-made basins in the Rhine Delta.
AU: Admiraal,-W.; van-der-Vlugt,-J.C.
AF: Natl. Inst. Public Health and Environ. Prot., P.O. Box 1, 3720 BA Bilthoven, Netherlands
SO: HYDROBIOL.-BULL. 1990. vol. 24, no. 1, pp. 23-36
NT: Special issue: Research on perturbed aquatic ecosystems.
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: The impact of eutrophication on the biogeochemical cycle of silicate in the Rhine Delta was analysed by 1) comparing the seasonal variation in river water, stagnant fresh water and coastal seawater and 2) observations in well-controlled experimental reservoirs subjected to different regimes of phosphate precipitation. The high input of dissolved silicate from Rhine water was rapidly depleted in receiving water systems through vigorous phytoplankton (diatom) growth. In reservoirs ca. 50% of the silicate input was retained over a seven years' observation period. Regeneration of silicate immobilized by diatoms was accelerated by very dense blooms of phytoplankton in reservoirs and in Lake IJssel that increased the pH value over 9.
AN: 2510601

                                                                   1163 of 1521  
TI: Stable carbon isotopes and the C:N ratio in the estuaries of the Pamlico and Neuse Rivers, North Carolina.
AU: Matson,-E.A.; Brinson,-M.M.
AF: Mar. Lab., Univ. Guam, UOG Stn., Mangilao 96923, Guam
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 6, pp. 1290-1300
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: The C:N and stable C isotope ratios ( delta  super(13)C) of sedimentary and seston organic C (OC) were used to identify OC sources and sites of deposition in two large estuaries in North Carolina. In the upper 10 km of the oligohaline zones, C:N ratios of sediment are characteristic of particulate terrestrial plant material (> 15). The  delta  super(13)C values increase linearly with distance from freshwater tributaries to the mouths of the estuaries ( similar to  20 ppt salinity), > 40 km from the ocean. Observed gradients in isotopic and C:N ratios imply that conservative mixing of freshwater and marine OC occurs. Phytoplankton in the estuaries produce at least 10 times more particulate OC than is delivered in runoff, however, and its biomass is recycled at rates much faster than those of water exchange. The observed gradients are therefore largely attributed to recycling of a resident pool of estuarine C, atmospheric CO sub(2), and an increasing marine bicarbonate fraction from the salt wedge downriver. Essentially lentic conditions in these estuaries ensure the dominance of in situ biological processes.
AN: 2510398

                                                                   1164 of 1521  
TI: The sulfur cycle of freshwater sediments: Role of thiosulfate.
AU: Joergensen,-B.B.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, DK-8000 Aarhus C, Denmark
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 6, pp. 1329-1342
LA: English
ER: F (Freshwater)
AB: The formation and pathways of thiosulfate (S sub(2)O sub(3) super(2-)) in anoxic sediment were studied in the Odder River and Brabrand Lake, Denmark. Time-course experiments were done in slurries with four  super(35)S tracers: SO sub(4) super(2-), H sub(2)S, and S sub(2)O sub(3) super(2-) with either the inner (oxidized) or the outer (reduced) S atom labeled. The two sediments gave similar results. Of all the S sub(2)O sub(3) super(2-) consumed in Brabrand Lake sediment, 6% was oxidized, 50% was reduced, and 44% was disproportionated. S sub(2)O sub(3) super(2-) disproportionation is an inorganic fermentation in certain SO sub(4) super(2-)-reducing bacteria by which the inner and outer S atoms are simultaneously transformed into SO sub(4) super(2-) and sulfide, respectively. Altogether, 28% of the S sub(2)O sub(3) super(2-)-S was converted into SO sub(4) super(2-) and 72% was converted into sulfide. S sub(2)O sub(3) super(2-) inhibited SO sub(4) super(2-) reduction by 75%. The immediate products of anoxic sulfide oxidation were 34% SO sub(4) super(2-) and 66% S sub(2)O sub(3) super(2-). Half of the oxidized sulfide was ultimately converted into SO sub(4) super(2-) and half was recycled back to sulfide via S sub(2)O sub(3) super(2-). Two-thirds of the S in the sulfide-thiosulfate "minicycle" remained at an oxidation state of -2. S sub(2)O sub(3) super(2-) is thus a key intermediate in the S cycle, both as a main product of anoxic sulfide oxidation and as a shunt between oxidative and reductive pathways.
AN: 2510378

                                                                   1165 of 1521  
TI: Distribution of dissolved trace metals in western Bay of Bengal.
AU: Satyanarayana,-D.; Murty,-P.V.S.P.
AF: Andhra Univ., Sch. Chem., Visakhapatnam 503 003, India
SO: INDIAN-J.-MAR.-SCI. 1990. vol. 19, no. 3, pp. 206-211
LA: English
ER: M (Marine)
AB: Concentrations of Ni, Zn, Cd, Cu, Mn, Pb and Fe were determined in 93 water samples (17 inshore and 7 offshore stations) collected at different depths from the western Bay of Bengal in March 1988. Surface distribution showed that relatively high concentrations of trace metals and nutrients are associated with low salinities in inshore and vice versa in the offshore waters. The depth profiles on Ni, Zn and Cd with surface depletion and bottom enrichment resembled those of nutrients, indicating their involvement in biogeochemical cycles. While the profiles of Cu were indicative of its involvement in the scavenging process at intermediate depth, those of Mn and Pb with surface enrichment and bottom depletion, appeared to be controlled by river inputs and anthropogenic atmospheric flux. However, surface enrichment and bottom depletion observed in the case of Fe profiles, contrary to its normal oceanic distribution, are attributed to the precipitation and/or adsorption on suspended particles leading to its transport to the sediments. The atomic ratios of Ni, Zn and Cd with nutrients were evaluated through their regression equations and compared with those reported earlier for Pacific, Atlantic and Indian Oceans.
AN: 2509850

                                                                   1166 of 1521  
TI: Analytical phosphorus fractionation of sediment trap material.
AU: Liebezeit,-G.
AF: Nationalparkverwalt., Oekosystemforsch. Niedersaechs. Wattenmeer, Virchowstr. 1, W-2940 Wilhelmshaven, FRG
SO: MAR.-CHEM. 1991. vol. 33, no. 1-2, pp. 61-69
LA: English
ER: M (Marine)
AB: Sediment trap samples from the Sea of Marmara, the North Sea, the South China Sea and the Voering Plateau were analysed for water- and acid-extractable inorganic and total organic phosphorus. Whereas water-extractable P accounts for < 3.6% of total P, acid-extractable P represents up to 62%. Inorganic phosphorus may originate from biogenic carbonate and silica, detrital clay minerals, fish debris and atmospheric fallout. The relative contributions from these sources are reviewed.
AN: 2508176

                                                                   1167 of 1521  
TI: Trace elements in lacustrine sediments.
OT: Elementi in traccia e sedimenti lacustri
AU: Baudo,-R.; Ferrari,-A.; Pranzo,-A.
CA: Istituto Italiano di Idrobiologia, Verbania Pallanza (Italy)
SO: DIRECTOR'-S-REPORT-ON-THE-SCIENTIFIC-ACTIVITY-OF-THE-INSTITUTE-FOR-THE-YEAR-1987.  RELAZIONE-DEL-DIRETTORE-SULL'-ATTIVITA-SCIENTIFICA-DELL'-INSTITUTO-NELL'-ANNO-1987. Bernardi,-R.-de-ed. 1989. no. 19 pp. 22-26
ST: DOC.-IST.-ITAL.-IDROBIOL. no. 19
LA: Italian
ER: F (Freshwater)
AB: Since 1986 sediments from several Italian lakes have been sampled with the objective of relating their chemical composition to the geochemistry of the respective drainage basins and eventually spotting possible modifications of the biogeochemical cycles due to human activities.
AN: 2505481

                                                                   1168 of 1521  
TI: Remobilization of Cu from marine particulate organic matter and from sewage.
AU: Paulson,-A.J.; Curl,-H.C.,Jr.; Cokelet,-E.D.
AF: Pacific Mar. Environ. Lab., NOAA, 7600 Sand Point Way NE, Seattle, WA 98115-0070, USA
SO: MAR.-CHEM. 1991. vol. 33, no. 1-2, pp. 41-60
LA: English
ER: M (Marine)
AB: The possible causes of enrichments of dissolved Cu in the bottom waters of Puget Sound were examined in a series of experiments designed to measure the release of Cu from surface marine organic suspended matter and from sewage-derived particles under ambient conditions. Decomposition of organic matter and ion-exchange controlled the release of about one-third of the Cu bound to large particles (> 53  mu m). In contrast, no Cu was released from smaller particles (< 53  mu m) suspended in natural seawater and only 5% of the Cu on small particles was released into artificial seawater with a low dissolved Cu concentration. Within 15 min of mixing primary primary effluent with natural seawater, 40% of the dissolved Cu was lost from solution by flocculation. Between 15 min and 4 days, 25% of the total effluent Cu was released back into solution. This release could have originated either from particulate Cu on the original sewage particles or from the flocculated Cu that was formed from dissolved Cu within the first 15 min.
AN: 2501133

                                                                   1169 of 1521  
TI: Zinc budget in the Mediterranean Sea: A hypothesis for non-steady-state behavior.
AU: Ruiz-Pino,-D.P.; Nicolas,-E.; Bethoux,-J.P.; Lambert,-C.E.
AF: Lab. Phys. et Chim. Mar., Univ. Paris 6, UA CNRS, B.P. 8, F06230 Villefranche-sur-Mer, France
SO: MAR.-CHEM. 1991. vol. 33, no. 1-2, pp. 145-169
LA: English
ER: M (Marine)
AB: The concentrations of Zn were determined in surface and deep-water samples at 11 sites in the Mediterranean Sea during the PHYCEMED 2 (Oct 1983) cruise. The Zn vertical profile is marked by a surface concentration (typically 3.0 nmol/kg in the Western Basin) higher than in the open ocean where the surface layer is Zn depleted. The subsurface layer (between 30 and 80 m) shows Zn and salinity minimun values along the path of the Atlantic inflow throughout the Western Basin. A weak intermediate maximum is present between 200- and 400-m depth, whereas Zn values are homogeneous in the deep waters from  similar to 300-m depth, as are T and S values. In deep water, the Zn/P ratios are similar to those of plankton; this is a good argument for a biological Zn cycle, which may explain the intermediate maximum caused by remineralization of organic matter settling from the euphotic layer. The deep layer is expected to be homogeneous as a result of the basin dynamics, whereas the biological cycle will induce a Zn depletion in the surface layer.
AN: 2501026

                                                                   1170 of 1521  
TI: The role of microorganisms in sedimentation in the ocean.
OT: Rol' mikroorganismov v sedimentatsionnykh protsessakh v okeane
AU: Stupakova,-T.P.; Dubinina,-G.A.; Demina,-L.L.
AF: IOAN SSSR, Moscow, USSR
SO: MIKROBIOLOGIYA-MICROBIOLOGY. 1991. vol. 60, no. 1, pp. 148-156
LA: Russian
ER: M (Marine)
AB: A study was made of the ability of Moraxella  sp. D-431 and fraction from individual cells of bacterioplankton taken from various depths in the Southwest Pacific to accumulate Cu, Ni, Co, Fe and Mn at the initial concentrations of 0.1-100  mu g/l. The accumulation rates of the metals were as follows: Cu = Co = Fe > Ni > Mn and they varied from 0.5 to 0.7 multiplied by 10 super(6) and from 2 to 3 multiplied by 10 super(7) in Moraxella) sp. and bacterioplankton respectively, which was by 2 or 3 orders higher than the respective values known for other hydrobionts. The results have shown that bacterioplankton contributes greatly towards heavy metal accumulation in suspended matter and sea water.
AN: 2499291

                                                                   1171 of 1521  
TI: (Accumulation of radionuclides by fish at the initial period of radioactive contamination of a river ecosystem.).
OT: Nakoplenie radionuklidov ryboj v nachal'nyj period radioaktivnogo zagryazneniya rechnoj ehkosistemy
AU: Vintsukevich,-N.V.; Tomilin,-Yu.A.
AF: Obl. Sanit. Ehpidemiol. Stn. Nikolaev, USSR
SO: EHKOLOGIYA. 1990. no. 5, pp. 35-40
LA: Russian
ER: F (Freshwater)
AB: The content of radionuclides in water components of the Dnieper River after the Chernobyl accident contamination was studied. Radionuclide composition of water, plants, bottom sediments and fish is considered. Concentration of radionuclides in various parts of body of bream, perch, pike-perch, roach, silver bream, white-eyed bream and sabrefish is tabled by individual elements. The least amount of  super(90)Sr was accumulated in muscular tissue. The paper compares estimated human consumption of contaminated fish with the standards of sanitation rules for nuclear power plants in the USSR.
AN: 2499105

                                                                   1172 of 1521  
TI: Stable isotopic and carbonate cyclicity in Lower Cretaceous deep-sea sediments: Dominance of diagenetic effects.
AU: Thierstein,-H.R.; Roth,-P.H.
AF: Geol. Inst., ETH Cent., CH-8092 Zurich, Switzerland
SO: MAR.-GEOL. 1991. vol. 97, no. 1-2, pp. 1-34
LA: English
ER: M (Marine)
AB: Oxygen and carbon isotopic variability of dominant (< 38  mu m) carbonate fraction within bedded, organic-carbon rich Lower Cretaceous sediment intervals from various DSDP sites are closely correlated with preservational changes in the carbonates. Isotopic fluctuations are absent where carbonate contents vary little and where the carbonate fraction is dominated by biogenic phytoplankton remains. Within each of the studied intervals oxygen and carbon isotopic ratios become increasingly more negative in samples with carbonate higher than about 60% in which the proportion of diagenetic microcarbonate increases rapidly. Carbon isotopic ratios show a trend towards positive values in samples with carbonate contents of less than 40% and strong signs of dissolution. The taxonomic composition of nannofossil assemblages varies little within single intervals, despite significant differential diagenesis among individual beds; this points towards ecological stability of oceanic surface waters during the deposition of alternating beds. Bedding is, however, closely related to changing bioturbation intensity, indicating repeated fluctuations of the deep-water renewal rates and oxygen supply.
AN: 2498518

                                                                   1173 of 1521  
TI: RRS Discovery  Cruise 191, 11 May-05 Jun 1990. Biogeochemical Ocean Flux Studies (BOFS Cruise A2).
AU: Angel,-M.V.; et-al.
AF: Inst. Oceanogr. Sci., Deacon Lab., Wormley, Godalming, Surrey GU8 5UB, UK
SO: CRUISE-REP.-INST.-OCEANOGR.-SCI.-DEACON-LAB. 1991. no. 222, 78 pp
LA: English
ER: M (Marine)
AB: This report describes the scientific activities carried out on Discovery  Cruise 191, the second in a series of three cruises on Discovery  run under the aegis of the Biogeochemical Ocean Flux Study (BOFS). The aim of these three cruises and two simultaneous cruises on Charles Darwin  was to conduct the Lagrangian experiment during the 1990 spring bloom, and to follow the fate of carbon fixed by photosynthesis.
AN: 2494743

                                                                   1174 of 1521  
TI: A statistical analysis of the contribution of structural groups of plankton to inorganic carbon fixation.
OT: Funktsional'naya rol' strukturnykh grupp planktona v fiksatsii neorganicheskogo ugleroda. Statisticheskij podkhod
AU: Smirnov,-N.A.; Demchev,-V.V.; Fedorov,-V.D.
AF: Gos. Univ., Moscow, USSR
SO: BIOL.-NAUKI. 1991. no. 3, pp. 141-159
LA: Russian
ER: M (Marine)
AB: Individual contribution was estimated of nannomicro-picophyto- and bacterioplankton to the total fixation of C in CO sub(2) at the expense of photosynthesis and dark assimilation (nannomicro- and picoplankton) and chemosynthesis and heterotrophic assimilation (bacterioplankton). Factorial experiment was made using a combination of methods of fractional filtration and selective biochemical inhibition. A general model of selective inhibition is presented. A statistical approach was developed to estimate the model parameters which imply intensive  super(14)C fixation by functional groups. The method was successfully applied to estimates of phyto- and bacterioplankton production in the White Sea estuaries.
AN: 2491286

                                                                   1175 of 1521  
TI: The organosulphur cycle: Aerobic and anaerobic processes leading to turnover of C sub(1)-sulphur compounds.
AU: Kelly,-D.P.; Baker,-S.C.
AF: Higher Educ. Aff., Nat. Environ. Res. Counc., Polaris House, North Star Ave., Swindon SN2 1EU, UK
CO: 6. Int. Symp. on Microbial Growth on C sub(1)-Compounds, Goettingen (FRG), 20-25 Aug 1989
SO: MICROBIAL-GROWTH-ON-C-sub1-COMPOUNDS. Andreesen,-J.R.;Bowien,-B.-eds. 1990. vol. 87, no. 3-4 pp. 241-246
ST: FEMS-MICROBIOL.-REV. vol. 87, no. 3-4
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: The processes generating and transforming those C sub(1)-organosulphur compounds which are major intermediates in the biogeochemical cycling of sulphur are summarised. The biological and chemical interconversions of the methylated sulphides, methane sulphonate, carbon disulphide and carbonyl sulphide are significantly influenced by diverse microorganisms, including autotrophic thiobacilli, methylotrophs, methanogens and sulphate-reducing bacteria. The major biogenic sulphur gas is dimethyl sulphide. A major atmospheric photochemical oxidation product from this is methane sulphonate, which can contribute to the acidity of rain. New data and ideas on the microbiological fate of methane sulphonate and of natural and anthropogenic carbon disulphide are presented.
AN: 2481631

                                                                   1176 of 1521  
TI: (PCB in the marine environment: Biogeochemistry and ecotoxicology.).
OT: Les polychlorobiphenyles (PCB) en milieu marin: Biogeochimie et ecotoxicologie
AU: Marchand,-M.; Abarnou,-A.; Marcaillou-Lebaut,-C.
AF: IFREMER Cent. Brest, DRO/EL, B.P. 70, 29280 Plouzane, France
SO: RAPP.-SCI.-TECH.-IFREMER. PLOUZANE-FRANCE-IFREMER-CENTRE-BREST,-SERVICE-DOCUMENTATION-PUBLICATIONS 1990. no. 18, 162 pp
LA: French
ER: M (Marine)
AB: This report synthesizes the knowledge on the behaviour, bioconcentration processes and ecotoxicity of PCB in the marine environment. Contamination levels of the French coasts are examined. Concentration levels, mechanisms and fluxes between geochemical reservoirs are assessed. Emphasis is given on sublethal effects and toxicity mechanisms. Quality standards used in European Community countries are listed. Conclusions and recommendations for environmental management and research are given.
AN: 2473465

                                                                   1177 of 1521  
TI: Dynamics of nutrient cycling of the Valdes Bay-Punta Cero pond system (Peninsula Valdes, Patagonia) Argentina.
AU: Esteves,-J.L.; Varela,-D.E.
AF: Cent. Nac. Patagonico, Blvd. Maritimo Alte. Brown s/n, 9120, Puerto Madryn, Argentina
SO: OCEANOL.-ACTA. 1991. vol. 14, no. 1, pp. 51-58
LA: English
ER: M (Marine)
AB: Valdes Bay constitutes a very interesting land-sea interface (LSI) at Peninsula Valdes. A gravel bank separates the bay from the open sea. The general characteristics (physical, chemical and biological) of this ecosystem and the chemical composition of the seawater coming in and out were analyzed. Nutrient cycling (nitrogen and phosphate) was very intense and involved a high primary productivity. These nutrients were principally produced at the gravel bank, where oxygen was consumed by heterotrophic activity and nitrification processes. The latter process consumed 1 to 7% of the oxygen. Extrapolating to the 35-km bank, a value of 6.8 metric tons of nitrogen would be produced daily.
AN: 2473049

                                                                   1178 of 1521  
TI: (Anaerobic biodegradation of calcified skeletons in the marine environment: 2. Chemical approach.).
OT: Biodegradation anaerobique des structures squelettiques en milieu marin: 2. Approche chimique
AU: Simon,-A.; Poulicek,-M.; Machiroux,-R.; Thorez,-J.
AF: Lab. Morphol., Syst. Ecol. Anim., Univ. Liege, Inst. Zool., quai Van Beneden 22, 4020 Liege, Belgium
SO: CAH.-BIOL.-MAR. 1990. vol. 31, no. 3, pp. 365-384
LA: French
ER: M (Marine)
AB: The experimental approach of anaerobic biodegradation processes was undertaken in the Calvi Bay (Corsica) and in an aquarium. Three types of calcified skeletons were considered: isolated prismatic layer of Pinna nobilis  (bivalvia) shell, nacreous layer of Nautilus pompilius  (cephalopod) shell and stereom of Sphaerechinus granularis  (echinoid) skeletal plates. The experimental material was embedded into organoclastic sand-filled closed jars retrieved periodically (1, 3, 6 or 9 months). I.C.P. and X-ray diffraction analysis, protein, chitin and enzymatic activity estimation showed that calcified skeleton biodegradation occurred very fast in anaerobiosis. Anoxic weathering was almost as fast as the aerobic one. Biodegradation patterns were very different from one type of calcified skeleton to another, caused by differences of organic matter distribution. In opposition to "classical" views, it is shown that anoxic biodegradation processes occur in very similar ways as oxic ones.
AN: 2473033

                                                                   1179 of 1521  
TI: (Influence of biodeposition by filter-feeding bivalves on the evolution of salt-marsh meiobenthic communities.).
OT: Influence de la biodeposition de bivalves filtreurs sur les peuplements meiobenthiques d'un marais maritime
AU: Dinet,-A.; Sornin,-J.-M.; Sabliere,-A.; Delmas,-D.; Feuillet-Girard,-M.
AF: Lab. Arago, 66650 Banyuls-sur-Mer, France
SO: CAH.-BIOL.-MAR. 1990. vol. 31, no. 3, pp. 307-322
LA: French
ER: B (Brackish)
AB: The influence of biodeposition by filter-feeding bivalves (Crassostrea gigas  and Mytilus edulis ) on the evolution of salt-marsh meiobenthic communities of the French Atlantic coast was studied over a 15-month period. Quantitative variations of meiofauna were analyzed monthly and, during some phases of the year cycle, at two or three-days intervals. The reasons for the recorded faunal variations were searched by principal component analysis among the main physico-chemical factors of the environment and more especially those related to the particulate organic matter of sediments. Over the concerned period, it seemed difficult to point out the subtle effects of biodeposition on meiofauna as the seasonal factor, basically thermal, was found responsible for the largest quantitative variations observed in the communities. Nematodes and harpacticoid copepods inversely reacted to the massive input of biodeposits. Finally, the most striking effect of these was a lowering of populations very likely due to the strong reduction of the substrate (negative Eh) and a rather high content of ammonium in interstitial waters.
AN: 2472387

                                                                   1180 of 1521  
TI: Effects of solar ultraviolet radiation on biogeochemical dynamics in aquatic environments: Report of a workshop held in Woods Hole, Massachusetts on 23-26 October 1989.
AU: Blough,-N.V.; Zepp,-R.G.
CA: Woods Hole Oceanographic Inst., MA (USA)
SO: TECH.-REP.-WOODS-HOLE-OCEANOGR.-INST. 1990. 201 pp
NT: NTIS Order No.: AD-A221 119/1/GAR. Contract N00014-90-J-1154.
RN: WHOI-90-09 (WHOI9009)
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: To better assess the possible ramifications of changing UV levels on biogeochemical dynamics, this workshop assembled a diverse group of experts, including atmospheric chemists and physicists and aquatic chemists, biochemists and biologists. Participants were asked to help identify and more clearly define: i) the potential effects of climate change on ground level solar UV (and visible) radiation, ii) the impacts of solar UV radiation on geochemical processes in aquatic systems, iii) the effects of solar UV radiation on biological processes, with emphasis on the possible effects of enhanced UV-B (280-320 nm) radiation. Participants were asked to discuss experimental and theoretical approaches to better characterize and model these processes on both regional and global scales. Questions that were addressed at the workshop included.
AN: 2465656

                                                                   1181 of 1521  
TI: Savannah River Ecology Laboratory annual report for the period ending July 31, 1989. Volume 2. Appendices.
CA: Savannah River Ecology Lab., Aiken, SC (USA). Div. of Stress and Wildlife Ecology
SO: 1990. 67 pp
NT: NTIS Order No.: DE90012110/GAR.
RN: SRO-819-20-Vol.2 (SRO81920Vol2)
LA: English
ER: F (Freshwater)
AB: Opportunities to study and understand the importance of both man-induced and natural environmental stresses are available to researchers on the Savannah River Site (SRS). Energy technologies have an impact on natural habitats and the associated plant and animal communities in a variety of ways. The transport, fate, and ecological effects of a variety of chemicals such as radionuclides, organic contaminants, and trace metals must be understood. In addition, construction, forestry programs, thermal releases, and other activities that affect terrestrial and aquatic environments are recognized nationally as having major impacts. These concerns have led to a variety of questions about the consequences of SRS activities on environmental systems and form a basis for research by scientists at Savannah River Ecology Laboratory (SREL). (Contract AC09-76SR00819. Sponsored by Department of Energy, Washington, DC. Portions of this document are illegible in microfiche products.)
AN: 2465620

                                                                   1182 of 1521  
TI: Annual report of ecological research for the period ending July 31, 1989. Volume 1. Main report.
CA: Savannah River Ecology Lab., Aiken, SC (USA). Div. of Stress and Wildlife Ecology
SO: 1990. 25 pp
NT: NTIS Order No.: DE90012109/GAR.
RN: SRO-819-20-Vol. 1 (1)
LA: English
ER: F (Freshwater)
AB: Opportunities to study and understand the importance of both man-induced and natural environmental stresses are available to researchers on the Savannah River Site (SRS). These concerns have led to a variety of questions about the consequences of SRS activities on environmental systems and form a basis for research by scientists at Savannah River Ecology Laboratory (SREL). Research at SREL can involve a variety of approaches, including field research, research in controlled environments such as greenhouses, and laboratory studies that require the use of sophisticated instrumentation. Highlights of research activities during FY89 at SREL over the past year are presented. Complete abstracts of specific projects are appended. (Contract AC09-76SR00819. Sponsored by Department of Energy, Washington, DC. Portions of this document are illegible in microfiche products.)
AN: 2465586

                                                                   1183 of 1521  
TI: Eutrophication in Hiroshima Bay.
AU: Seiki,-T.; Date,-E.; Izawa,-H.
AF: Hiroshima Prefect. Res. Cent. Environ. Sci., 1-6-29, Minami-machi, Minami-ku, Hiroshima 734, Japan
CO: Int. Conf. on the Environmental Management of Enclosed Coastal Seas '90: EMECS '90, Kobe, Hyogo Prefect. (Japan), 3-6 Aug 1990
SO: ENVIRONMENTAL-MANAGEMENT-AND-APPROPRIATE-USE-OF-ENCLOSED-COASTAL-SEAS-EMECS-'-90. Goda,-T.;et-al.-eds. 1991. vol. 23 pp. 95-99
ST: MAR.-POLLUT.-BULL. vol. 23
LA: English
ER: M (Marine)
AB: Several researches for eutrophication in the northern Hiroshima Bay were carried out to investigate nutrient budgets in aquatic circulation processes, i.e. primary production, settling flux of particulate organic matter (POM) and the benthic remineralization. It became apparent from these investigations that primary production contributed to the organic pollution in the northern bay than land based organic loadings by a factor of 10, that approx. 70-80% of the POM originating in phytoplankton were easily remineralized into inorganic nutrients during the settling process in water, and that approx. 60% of nitrogen and 70% of phosphorus in POM settled on the sediments might be returned to the water column by the release from benthic sediment.
AN: 2463112

                                                                   1184 of 1521  
TI: Creation of a new nonfeeding aquaculture system in enclosed coastal seas.
AU: Inui,-M.; Itsubo,-M.; Iso,-S.
AF: Tech. Cent., Tokyo Kyuei Co., Ltd., Saitama Prefect., Kawaguchi City, Shiba-tsurugamaru 6906-10, Japan
CO: Int. Conf. on the Environmental Management of Enclosed Coastal Seas '90: EMECS '90, Kobe, Hyogo Prefect. (Japan), 3-6 Aug 1990
SO: ENVIRONMENTAL-MANAGEMENT-AND-APPROPRIATE-USE-OF-ENCLOSED-COASTAL-SEAS-EMECS-'-90. Goda,-T.;et-al.-ed.. 1991. vol. 23 pp. 321-325
ST: MAR.-POLLUT.-BULL. vol. 23
LA: English
ER: M (Marine)
AB: Eutrophication has occurred in the enclosed coastal seas, presenting a serious environmental problem. To prevent such a situation, we propose to create a new biogeochemical, recycle system whereby nutrients flowing into the seas would be returned to land by means of a combined system of aquacultures of non-feeding type. The system consists of culture of seaweeds, culture of filter feeding animals, and culture of mud feeding animals. However, the development of culture in the enclose coastal seas inevitably leads to overproduction. To promote and sustain the system, it is important not only to develop the industrial utilization of each of the cultured products, but also set up an organization of cooperations between the fishery cooperatives, local citizens and local governments.
AN: 2462117

                                                                   1185 of 1521  
TI: Scavenging processes of marine particles in Osaka Bay.
AU: Montani,-S.; Mishima,-Y.; Okaichi,-T.
AF: Dep. Bioresour. Sci., Fac. Agric., Kagawa Univ., Miki, Kagawa 761-07, Japan
CO: Int. Conf. on the Environmental Management of Enclosed Coastal Seas '90: EMECS '90, Kobe, Hyogo Prefect. (Japan), 3-6 Aug 1990
SO: ENVIRONMENTAL-MANAGEMENT-AND-APPROPRIATE-USE-OF-ENCLOSED-COASTAL-SEAS-EMECS-'-90. Goda,-T.;et-al.-eds. 1991. vol. 23 pp. 107-111
ST: MAR.-POLLUT.-BULL. vol. 23
LA: English
ER: M (Marine)
AB: The scavenging processes of marine particles in Osaka Bay was investigated using bioelement (C,N,P) distribution as an indicator. Nutrient concentrations in the water and bioelement contents in suspended particles, sinking particles and surface sediment were monitored for three years (1985 to 1987). Large variations appeared to depend on environmental conditions. Bioelement concentrations in suspended particles and sinking particles decrease remarkably going from the inner part of the bay to the offshore water area. Our results suggested that the position of the tidal front in Osaka Bay agrees very closely with 20-30 m water depth; the chemical character of suspended particles and sinking particles was considerably different from across the tidal frontal area. According to the chemical character of sinking particles at the offshore water area station, these particles are mainly made up of "old particles" of which the labile organic matter fraction was already decomposed. Sedimentation of nitrogen in the inner part of the bay accounts for approximately 6% of all nitrogen inputs to Osaka Bay.
AN: 2461904

                                                                   1186 of 1521  
TI: Impact of nutrient enrichment and their relation to the algal bloom in the Adriatic Sea.
AU: Vukadin,-I.
AF: Inst. Oceanogr. and Fish., 58000 Split, Yugoslavia
CO: Int. Conf. on the Environmental Management of Enclosed Coastal Seas '90: EMECS '90, Kobe, Hyogo Prefect. (Japan), 3-6 Aug 1990
SO: ENVIRONMENTAL-MANAGEMENT-AND-APPROPRIATE-USE-OF-ENCLOSED-COASTAL-SEAS-EMECS-'-90. Goda,-T.;et-al.-eds. 1991. vol. 23 pp. 145-148
ST: MAR.-POLLUT.-BULL. vol. 23
LA: English
ER: M (Marine)
AB: Extraordinary manifestations of eutrophication in the Adriatic Sea during the last few years have been due to the combined effects of different physico-chemical and meteorological factors. Permanent inputs of nutrients, particularly in the northern Adriatic via river runoffs and municipal sewage during calm summers, cause marked stratification of the water column and reduction of horizontal advection. These two effects provide the ideal conditions for single a species bloom. An attempt has been made to calculate the nutrient balance which allows a better interpretation of algal blooms in the Adriatic.
AN: 2461673

                                                                   1187 of 1521  
TI: Nitrogen forms in the South Atlantic.
OT: Formy azota v Yuzhnoj Atlantike
AU: Arzhanova,-N.V.; Zubarevich,-V.L.; Naletova,-I.A.
AF: VNIRO, Moscow, USSR
SO: OKEANOLOGIYA-OCEANOLOGY. 1990. vol. 30, no. 6, pp. 936-944
LA: Russian
ER: M (Marine)
AB: Spatial distribution of mineral and organic forms of N and relations between the 2 forms in the water column is considered for various latitudinal zones of the South Atlantic. It is stated that a considerable decrease in the total content of mineral forms of N from Antarctica to the equator (from 15-30 down to 1  mu g-at/l in the photic layer) the N sub(org) level was maintained at 15-20 and 10-20  mu g-at/l at the surface and in deeper layers respectively. High concentrations of N (> 30 and > 20  mu g-at/l at the surface and in deeper layers respectively were typical of the Antarctic Convergence and subtropical anticyclonic zones). The contribution of urea N and aminoacids to the total N sub(org) was found to vary from 5 to 30 and 20% respectively.
AN: 2459303

                                                                   1188 of 1521  
TI: (Basic provisions of the theory of functioning of aquatic ecosystems.).
OT: Osnovnye polozheniya teorii funktsionirovaniya vodnykh ehkosistem
AU: Alimov,-A.F.
AF: ZIN AN SSSR, Leningrad, USSR
SO: GIDROBIOL.-ZH.-HYDROBIOL.-J. 1990. vol. 26, no. 6, pp. 3-12
LA: Russian
AB: The paper reviews the major points of the theory of functioning of water ecosystems which is regarded as a variable interaction of fluxes of energy, matter and information which ensure stability of these systems under specific conditions. Stability is a relatively constant value of the average structural and functional characteristics in specific conditions for a sufficiently long period of time. The author considers the potential ways of studying the structure, formation and interaction of energy, matter and information fluxes from the angle of the theories of biological production, of information and thermodynamics.
AN: 2459020

                                                                   1189 of 1521  
TI: Ocean-atmosphere interactions in the global biogeochemical sulfur cycle.
AU: Andreae,-M.O.
AF: Biogeochem. Dep., Max Planck Inst. Chem., P.O. Box 3060, D-6500 Mainz, FRG
CO: 32. IUPAC Congr. in the Section on Atmospheric and Marine Chemistry, Stockholm (Sweden), 2-7 Aug 1989
SO: MAR.-CHEM. 1990. vol. 30, no. 1-3, pp. 1-29
NT: Special issue.
LA: English
ER: M (Marine)
AB: Marine algae produce dimethylsulfonium propionate, which may be enzymatically cleaved to yield the volatile dimethylsulfide (DMS). There are no simple relationships with algal biomass or primary productivity, but the concentration of DMS in the ocean is regulated by a complicated interplay of algal speciation and trophic interactions. Part of the biogenically produced DMS diffuses into the atmosphere, where it is oxidized, mostly to aerosol sulfate. The ability of these aerosol particles to nucleate cloud droplets, and thereby influence the reflectivity and stability of clouds, forms the basis of a proposed geophysiological feedback loop involving phytoplankton, atmospheric sulfur, and climate. Carbonylsulfide (COS) is produced photochemically from dissolved organic matter in seawater. Diffusion of COS from the ocean to the atmosphere is a globally significant source of this gas, which participates in the stratospheric ozone cycle. Hydrogen sulfide and carbon disulfide are produced in the surface ocean, but the oceans are a minor source to the troposphere.
AN: 2453079

                                                                   1190 of 1521  
TI: Chemical processes at the sediment-water interface.
AU: Santschi,-P.; Hoehener,-P.; Benoit,-G.; Buchholtz-ten-Brink,-M.
AF: Texas A&M Univ., Galveston, TX 77553-1675, USA
CO: 32. IUPAC Congr. in the Section on Atmospheric and Marine Chemistry, Stockholm (Sweden), 2-7 Aug 1989
SO: MAR.-CHEM. 1990. vol. 30, no. 1-3, pp. 269-315
NT: Special issue.
LA: English
ER: M (Marine)
AB: Discusses chemical transformations that take place during early diagenesis in sediments, and which are fueled by supply rates of organic carbon and electron acceptors. Current knowledge of the cycling of the electron acceptors O, N, Mn, Fe and S is assessed, and the important role of transport reactions described. Elemental fluxes across the sediment-water interface can be described from first principles only if the coupling of physical, chemical and biological processes is better understood.  Chemical reactions within this region must be considered an integral part of a three-dimensional network of interactions. Hence, the apparent coexistence of chemical species considered "incompatible" by thermodynamic models can be a consequence of the three-dimensional nature of redox gradients. The microbiological, chemical and physical interactions of dissolved, colloidal and particulate organic carbon, and iron and manganese oxides play a crucial role in the early diagenetic reactions at the sediment-water interface. Their effects on diagenetic reactions, and on trace elements in solution and adsorbed to particles, are discussed. Furthermore, we emphasize the way in which hydrodynamics can control elemental fluxes in environments with high carbon rain rates.
AN: 2452902

                                                                   1191 of 1521  
TI: Importance of continental margins in the marine biogeochemical cycling of carbon and nitrogen.
AU: Walsh,-J.J.
AF: Dep. Mar. Sci., Univ. South Florida, 140 7th Ave. S., St. Petersburg, FL 33701, USA
SO: NATURE. 1991. vol. 350, no. 6313, pp. 53-55
LA: English
ER: M (Marine)
AB: The continental margins occupy less than 20% of the surface area of the world ocean, and it is widely assumed that they do not play a significant part in the oceanic biogeochemical cycles of carbon and nitrogen. Data from 32 sediment-trap moorings, 16 in the deep sea and 16 on the continental slope, suggest that at an average depth of 2,650 m on the slope, the combined rain of surviving shelf and slope particles yields a mean carbon flux of 6.9 g C/m super(2)/yr - about ten times that at the same average depth in the deep sea (0.8 g C/m super(2)/yr). Because the area of the deep sea is about ten times greater than that of the continental slopes, using the sediment-trap data and assuming a carbon/nitrogen ratio of 5:1, the equivalent total particulate offshore nitrogen loss is 0.5 x 10 super(14) g N/yr at 2,650 m. If these trap observations are generally representative of the oceans and continental margins, then the supply of dissolved nitrate to the overlying euphotic zones should also be similar. Here I provide an independent estimate of the annual supply of onwelling nitrate from the deep sea to the shelves and find that it may balance the offshore flux of carbon, suggesting that the continental margins and deep sea are equally important in the carbon and nitrogen biogeochemical cycles.
AN: 2449252

                                                                   1192 of 1521  
TI: Nitrogen, phosphorus, and biogenic silicon budgets for the northern Adriatic Sea.
AU: Degobbis,-D.; Gilmartin,-M.
AF: Rudjer Boskovie Inst., Cent. Mar. Res., 52210 Rovinj, Yugoslavia
SO: OCEANOL.-ACTA. 1990. vol. 13, no. 1, pp. 31-45
LA: English
ER: M (Marine)
AB: Proximate nitrogen, phosphorus and biogenic silicon budgets were calculated for the northern Adriatic, one of the most productive subregions of the Mediterranean Sea, and the main processes driving the biogeochemical cycle of these biogenic elements were ranked as to their relative importance. The results support the assumed importance of the nutrient contribution by the Po River (at least 50% of the inputs) whose waters thereby influence a large part of the northern Adriatic.
AN: 2448473

                                                                   1193 of 1521  
TI: Dynamics and controls of methane oxidation in a Danish wetland sediment.
AU: King,-G.M.
AF: Darling Mar. Cent., Univ. Maine, Walpole, ME 04573, USA
SO: FEMS-MICROBIOL.-ECOL. 1990. vol. 74, no. 4, pp. 309-324
LA: English
ER: F (Freshwater)
AB: The patterns and controls of methane oxidation in a Danish wetland sediment have been determined using a combination of slurry and intact core techniques. Results from slurries indicated that methane oxidation was effectively inhibited by low concentrations of nitrapyrin (9  mu M) and acetylene (0.5  mu M) but that oxidation was relatively insensitive to pH between 6 and 8; in addition, high concentrations of ammonia (1 mM) decreased oxidation, especially at alkaline pH. Kinetic analyses of methane oxidation in slurries indicated that V sub(max) was high relative to values reported for other sediments, that V sub(max) changed seasonally, that K sub(m) was consistently low (2-4  mu M) and that threshold values were low (3-5 nM) but insufficient to allow consumption of atmospheric methane. Analyses based on intact cores indicated that the extent of methane oxidation was highly dependent on oxygen availability, particularly as affected by benthic photosynthesis or the presence of algal mats.
AN: 2447638

                                                                   1194 of 1521  
TI: Biological removal of dimethyl sulphide from sea water.
AU: Kiene,-R.P.; Bates,-T.S.
AF: Univ. Georgia Mar. Inst., Sapelo Island, GA 31327, USA
SO: NATURE. 1990. vol. 345, no. 6277, pp. 702-705
LA: English
ER: M (Marine)
AB: Dimethyl sulphide (DMS) is an important sulphur-containing trace gas in the atmosphere. Relatively little is known about the biogeochemical and physical processes that control the concentration of DMS in sea water. Here we present data from incubation experiments, carried out at sea, which show that DMS is removed by microbial activity. In the eastern, tropical Pacific Ocean, DMS turnover is dominated by biological processes, with turnover times for biological DMS removal generally more than ten (3-430) times faster than turnover by ventilation to the atmosphere. The results have significant implications for climate feedback models involving DMS emissions, and highlight the importance of the microbial food web in oceanic DMS cycling.
AN: 2447583

                                                                   1195 of 1521  
TI: Sequentially extracted metals in Adirondack lake sediment cores.
AU: White,-J.R.; Gubala,-C.P.
AF: Sch. Pub. and Environ. Aff., Indiana Univ., Bloomington, IN 47405, USA
SO: J.-PALEOLIMNOL. 1990. vol. 3, no. 3, pp. 243-252
LA: English
ER: F (Freshwater)
AB: Metal deposition patterns have been examined in sediment cores from 3 lakes in the Adirondack region of New York (USA). Sequential chemical extraction of Al, Fe, Mn, Pb, and Zn has yielded information on their chemical nature and potential mechanisms involved in their deposition. Results indicate historical changes in watershed chemistry may have influenced metal chemistry in these lakes. In two systems known to have been acidified in recent time by acidic deposition (Big Moose L. & Deep L.), concentrations of labile Al (in Cl-C4 fraction) increase after 1940-1950, corresponding with lake acidification as inferred from diatom assemblages. Chemical stratigraphies of Fe and Mn are most likely dominated by internal biogeochemical cycling within sediments.
AN: 2447343

                                                                   1196 of 1521  
TI: TOXIWASP.
AU: Schramm,-K.-W.
AF: Dep. Ecol. Chem. and Geochem., Univ. Bayreuth, Bayreuth, FRG
SO: TOXICOL.-ENVIRON.-CHEM. 1990. vol. 26, no. 1-4, pp. 55-60
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: TOXIWASP combines most of the kinetic structure of EXAMS 2 with the transport capabilities of WASP (Water Analysis Simulation Program). TOXIWASP uses variable chemical degradation rates from chemical properties and the environmental conditions of the aquatic ecosystem. These rates are reduced from pseudo first-order rates to first-order rates including the processes hydrolysis, biotransformation, phototransformation, oxidation, and volatilisation. Assuming ultimate local equilibrium, and using a chemical dependent partition coefficient as well as spatially varying environmental carbon fractions, sorption onto sediments and biomass is calculated. Environmental alternations could be specified in any time scale by providing monitoring data. TOXIWASP generates total sediment and chemical concentrations every time step in every segment, including surface water, subsurface water, surface bed and subsurface bed. Advection, dispersion, mass loading, sedimentation, and scour affect sediment concentration in the water column and in the bed sediment concentrations depend on burial and erosion. In addition chemical concentrations are influenced by degradation, sediment-water dispersion, and percolation. Lateral transport of chemical within the bed is neglected and transport data are not calculated in the program.
AN: 2444591

                                                                   1197 of 1521  
TI: A nitrogen-based model of plankton dynamics in the oceanic mixed layer.
AU: Fasham,-M.J.R.; Ducklow,-H.W.; McKelvie,-S.M.
AF: Inst. Oceanogr. Sci., Deacon Lab., Nat. Environ. Res. Counc., Brook Rd., Wormley, Godalming GU8 5UB, UK
SO: J.-MAR.-RES. 1990. vol. 48, no. 3, pp. 591-639
LA: English
ER: M (Marine)
AB: As a first step toward the development of coupled, basin scale models of ocean circulation and biogeochemical cycling, the authors present a model of the annual cycles of plankton dynamics and nitrogen cycling in the oceanic mixed layer. The model is easily modified and runs in FORTRAN on a personal computer. In our initial development and exploration of the model's behavior we have concentrated on modeling the annual cycle at Station "S" near Bermuda using seven compartments (Phytoplankton, Zooplankton, Bacteria, Nitrate, Ammonium, Dissolved organic nitrogen and Detritus). This choice of compartments and the attendant flows permits a functional distinction between new and regenerated production. We have examined over 200 different runs and carried out sensitivity analyses. These model runs reproduce the annual cycles of areal NPP, an average annual NPP, new production, and particulate N flux values reported in the literature. The model demonstrates that currently accepted values for these annual fluxes can be reconciled only if the f-ratio has a high annual average. At present, the annual average f-ratio is poorly quantified due to undersampling in fall and winter.
AN: 2443163

                                                                   1198 of 1521  
TI: On the biochemical degradation of urea in aqueous solution--review.
OT: Zum biochemischen Harnstoffabbau in waessriger Loesung--Uebersicht
AU: Gunkel,-K.; Kuemmel,-R.; Tuempling,-W.V.
AF: Berirkshygieneinsp. und -Inst. Max von Pettenkofer, Juri-Gagarin-Ring 124, Erfurt, 5020, FRG
SO: ACTA-HYDROCHIM.-HYDROBIOL. 1990. vol. 18, no. 1, pp. 3-20
LA: German
ER: M (Marine); B (Brackish); F (Freshwater)
AB: Urea from natural and anthropogenic sources is one of the most interesting nitrogen compounds in an aquatic environment. Results of experimental investigations are presented for the successive biochemical urea transformation into nitrates via ammonium and nitrite species. Kinetic models based on a combination of Michaelis-Menten and Monod equations have been derived which describe reasonably well the course of the enzymatic reactions and the concentration-time profiles of different N oxidation states. Main factors affecting the rates of nitrogen metabolization are the initial concentration of ureolytic bacteria, the physical state of the nitrifying microorganisms, and the concentration of toxic organics added to the system under study.
AN: 2441473

                                                                   1199 of 1521  
TI: EXAMS 2. EXposure Analysis Modeling System.
AU: Schramm,-K.-W.
AF: Dep. Ecol. Chem. and Geochem., Univ. Bayreuth, Bayreuth, FRG
SO: TOXICOL.-ENVIRON.-CHEM. 1990. vol. 26, no. 1-4, pp. 73-82
LA: English
AB: EXAMS 2 was developed by Burns et al. for rapid evaluation of the behavior of organic chemicals in aquatic ecosystems. EXAMS 2 computes from the chemistry and the relevant transport and physicochemical properties of the compounds and the ecosystem: Expected environmental concentrations. The fate of chemicals due to transport and transformation processes. The persistence of chemicals in the systems once chemical loadings terminate. The program is interactive and allows the user to define and store the properties of the chemicals and environments. Loadings, transport, and transformations are combined into a set of differential equations assuming conservation of mass. Entering and leaving chemical mass into and from the environment is treated as the algebraic sum of external loadings, transport processes that export chemicals from the system, and transformation processes that convert chemicals to their transformation products. Water bodies can be combined via a set of several compartments or distinct zones of the environment as benthic, epilimnic, hypolimnic, and littoral subzones. EXAMS 2 accepts standard water-quality and limnological parameters.
AN: 2441428

                                                                   1200 of 1521  
TI: MESEP: Modelling environmental scenarios in ponds.
AU: Schramm,-K.-W.; Goss,-K.-U.
AF: Dep. Ecol. Chem. and Geochem., Univ. Bayreuth, Bayreuth, FRG
SO: TOXICOL.-ENVIRON.-CHEM. 1990. vol. 26, no. 1-4, pp. 123-128
LA: English
ER: F (Freshwater)
AB: MESIP is fugacity model which can predict the fate of organic hydrophobic chemicals in aquatic ecosystems. In this paper a short introduction to the mathematical model is presented together with a more detailed listing of the required input data. Comparison of the calculated and measured fate of a fluorescent whitening compounds in an artificial outdoor pond is shown.
AN: 2441243

                                                                   1201 of 1521  
TI: (Mercury in the marine environment: Biogeochemistry and ecotoxicology.).
OT: Le mercure en milieu marin: Biogeochimie et ecotoxicologie
AU: Cossa,-D.; Thibaud,-Y.; Romeo,-M.; Gnassia-Barelli,-M.
AF: IFREMER Cent. Nantes, B.P. 1049, 44037 Nantes Cedex, France
SO: RAPP.-SCI.-TECH.-IFREMER. 1990. no. 19, 130 pp
LA: French
ER: M (Marine)
AB: This report synthesizes the knowledge on the biogeochemical cycle, bioconcentration processes and ecotoxicity of mercury in the marine environment. Man induced changes on the mercury cycle, especially along the French coasts, are reviewed. Concentration levels, mechanisms and fluxes between geochemical reservoirs are assessed. Emphasis is given on sublethal effects and toxicity mechanisms. Quality standards used in European Community countries are listed. Conclusions and recommendations for environmental management and research are given.
AN: 2440884

                                                                   1202 of 1521  
TI: Bacterial regeneration of ammonium and phosphate as affected by the carbon:nitrogen:phosphorus ratio of organic substrates.
AU: Tezuka,-Y.
AF: Otsu Hydrobiol. Stn., Kyoto Univ., Shimosakamoto, Otsu 520-01, Japan
SO: MICROB.-ECOL. 1990. vol. 19, no. 3, pp. 227-238
LA: English
ER: F (Freshwater)
AB: The effect of carbon: nitrogen: phosphorus (C:N:P) ratio of organic substrates on the regeneration of ammonium and phosphate was investigated by growing natural assemblages of freshwater bacteria in mineral media supplemented with the simple organic C, N, and P sources (glucose, asparagine, and sodium glycerophosphate, respectively) to give 25 different substrate C:N:P ratios. Both ammonium and phosphate were regenerated when C:N and N:P atomic ratios of organic substrates were  less than or equal to 10:1 and  less than or equal to 16:1, respectively. Only ammonium was regenerated when C:N and N:P ratios were  less than or equal to 10:1 and  greater than or equal to 10-20:1, respectively. On the other hand, neither ammonium nor phosphate was regenerated when C:N and N:P ratios were  greater than or equal to 15:1 and  greater than or equal to 5:1, respectively. In no case was phosphate alone regenerated. As bacteria were able to alter widely the C:N:P ratio of their biomass, the growth yield of bacteria appeared primarily dependent on the substrate carbon concentration, irrespective of a wide variation in the substrate C:N:P ratio.
AN: 2439238

                                                                   1203 of 1521  
TI: (Antarctic ice record: Climate and atmosphere evolution over the last climatic cycle.).
OT: Archives glaciaires de l'Antarctique: Climat et environnement atmospherique au cours du dernier cycle climatique
AU: Raynaud,-D.
AF: Lab. Glaciol. et Geophys. Environ., CNRS, B.P. 96, 38402 St Martin d'Heres Cedex, France
SO: OCEANOLOGY:-EVENTS,-FUTURE-AND-PREDICTION..  OCEANOLOGIE:-ACTUALITE-ET-PROSPECTIVE. Denis,-M.-ed. 1989. pp. 155-167
LA: French
ER: M (Marine)
AB: The advantages and limitations of the ice record are discussed and compared with the oceanic record. Three main aspects of the Antarctic ice record over the last climatic cycle are presented: the evolution of atmospheric temperature in Antarctica, the evolution of two important greenhouse gases (CO sub(2) and CH sub(4)) and evolution of various aerosols of different origins. The results indicate the close interactions between biogeochemical cycles, atmospheric composition and climate.
AN: 2437344

                                                                   1204 of 1521  
TI: The coral reef: An owner-built, high-density, fully-serviced, self-sufficient housing estate in the desert - or is it?.
AU: Kinsey,-D.W.
AF: Great Barrier Reef Mar. Park Auth., Townsville, Qld. 4810, Australia
CO: Joint Israel-U.S. Workshop on Marine Symbiosis: From Molecular Biology to Ecosystem Function, Eilat (Israel), 11-16 Mar 1990
SO: SYMBIOSIS. 1991. vol. 10, no. 1-3, pp. 1-22
LA: English
ER: M (Marine)
AB: Coral reefs usually are portrayed as the ultimate example of exosystem symbiosis and organisation. It has been suggested that this extreme of integration, and perhaps predictability, is the result of necessity in the "desert" of the oceanic world. Actually, reefs do not need to live in oceanic deserts. In fact, it is doubtful whether the oligotrophic oceans are as desert-like as once supposed. Reefs develop in a wide range of nutrient environments, and the resulting configuration is extremely variable on all scales from gross reef morphology down to detailed community structure. Nevertheless, the majority of reefs have very predictable zonation, zonal width, sources and sink areas, and community metabolic rates. The paper examines the development of the author's "philosophy" of reef biogeochemical performance over 30 years and also draws heavily on ideas developed by S.V. Smith.
AN: 2431798

                                                                   1205 of 1521  
TI: Impacts of forests on water chemistry.
AU: Mahendrappa,-M.K.
AF: For. Canada, Marit. Reg., P.O. Box 4000, Fredericton, N.B. E3B 5P7, Canada
CO: Symp. on the Acidification of Organic Waters in Kejimkujik National Park, Nova Scotia, Canada, Wolfville, N.S. (Canada), 25-27 Oct 1988
SO: WATER-AIR-SOIL-POLLUT. 1989. vol. 46, no. 1-4, pp. 61-72
LA: English
ER: F (Freshwater)
AB: Forest canopies and soil organic horizons have been identified as 2 major components of forest ecosystems interacting with and altering the chemistry of rainwater. Data, collected over a 13-yr period from different softwood and hardwood stands located in central New Brunswick, are presented to demonstrate differences among stands in their ability to alter the chemistry of rainwater. In both the canopies and the soil organic horizons, retention and exchange processes are affective in altering the chemistry of rainwater. Significant species effects are recognized in the partitioning of rainwater into throughfall, stemflow, and interception, and in altering of its chemistry. Stemflow components generally contribute to acidity, while throughfall reduces acidity of rainwater. Some of the chemical characteristics of rainwater reaching the forest floor are shown to be similar to those of streams associated with the forest stands.
AN: 2429129

                                                                   1206 of 1521  
TI: Carbon and nitrogen budgets of the Arabian Sea.
AU: Somasundar,-K.; Rajendran,-A.; Kumar,-M.D.; Gupta,-R.S.
AF: Natl. Inst. Oceanogr., Dona Paula, Goa 403 004, India
SO: MAR.-CHEM. 1990. vol. 31, no. 4, pp. 363-377
LA: English
ER: M (Marine)
AB: From the available data, carbon and nitrogen budgets have been estimated for the Arabian Sea (0-25 degree N, 50-80 degree E), taking into consideration the possible sources of fluxes. By our model calculations the annual fluxes into and out of the Arabian Sea were estimated to be 446 and 530 trillion grams (Tg) for carbon, and 8.06 and 3.60 Tg for nitrogen, respectively. The carbon budget was found to be negatively balanced by 84 Tg/year. A possible source to compensate for this deficit could be from the northward movement of Antarctic Bottom Water in the bottom layers, which are probably enriched with anthropogenic carbon dioxide. Annually,  similar to 74 Tg of carbon in the form of carbon dioxide escaped into the atmosphere from the Arabian Sea; this is higher than the global average fluxes from the tropical oceans. The percentage loss of carbon (14.0%) to the atmosphere was much lower than that of nitrogen (56.9%). Out of the total amount of denitrified nitrogen (29.5 Tg) only  similar to 7% was lost to the atmosphere. This model suggests that  similar to 6 Tg N/year of denitrified nitrogen of the world's oceans could be liberated to the atmosphere through the surface layer of denitrified areas.
AN: 2428239

                                                                   1207 of 1521  
TI: Nd isotopes as tracers in water column particles: The western Mediterranean Sea.
AU: Grousset,-F.E.; Henry,-F.; Minster,-J.F.; Monaco,-A.
AF: UA CNRS 197, Dep. Geol.-Oceanogr., Univ. Bordeaux I, Ave. Facultes, 33405 Talence Cedex, France
SO: MAR.-CHEM. 1990. vol. 31, no. 4, pp. 389-407
LA: English
ER: M (Marine)
AB: Measurements of Nd isotopic ratios in sediment trap materials are reported on samples obtained from the western Mediterranean Sea margin (Gulf of Lions). Trap samples from two different seasons were examined. For the summer-autumn series (Oct), the fluvial inputs are relatively weak, and the Saharan aerosol influence is clearly identified in the particles trapped in the surface water (0-100 m). Isotopic ratios can be explained by a mixture of low values, corresponding to Saharan detrital aerosol particles, with higher radiogenic ratios similar to values reported earlier for the Mediterranean watermass, which are carried by biogenic particulate components. On the other hand, bottom layers are more probably invaded by particles coming from the shelf and the neighbouring rivers. For the winter-spring series (Mar), high particle fluxes coming from the distant Rhone river and advected along the shelf and margin by ocean currents, are the dominant component in the surface and intermediate trap-samples. However, the near-bottom particulate flux and the sediments reflect the more local river signature.
AN: 2425029

                                                                   1208 of 1521  
TI: Phycological reviews 2: The role of dissolved organic nitrogen in phytoplankton nutrition, cell biology and ecology.
AU: Antia,-N.J.; Harrison,-P.J.; Oliveira,-L.
AF: Dep. Bot., Univ. British Columbia, Vancouver, B.C. V6T 2B1, Canada
SO: PHYCOLOGIA. 1991. vol. 30, no. 1, pp. 1-89
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: This review aims to cover all conceivable aspects of both marine and freshwater dissolved organic nitrogen (DON) from the moment of its inception (through release by various aquatic organisms) to its assimilation (and utilization as nutrient) by phytoplankton, to its metabolism and consequent impact on cell biology, and its ultimate turnover within the framework of ecological interactions. Attention is focused on DON vis-a-vis phytoplankton while dealing with the above mentioned aspects, although DON is also known to play various roles in the biology of heterotrophic bacteria and protozoa.
AN: 2423373

                                                                   1209 of 1521  
TI: Bioturbation and manganese cycling in hemipelagic sediments.
AU: Aller,-R.C.
AF: Mar. Sci. Res. Cent., SUNY, Stony Brook, NY 11794-5000, USA
CO: The Deep Sea Bed: Its Physics, Chemistry and Biology. A Discussion, London (UK), 5-6 Apr 1989
SO: THE-DEEP-SEA-BED:-ITS-PHYSICS,-CHEMISTRY-AND-BIOLOGY. Charnock,-H.;Edmond,-J.M.;McCave,-I.N.;Rice,-A.L.;Wilson,-T.R.S.-eds. 1990. vol. 331 pp. 51-68
ST: PHILOS.-TRANS.-R.-SOC.-LOND.,-A. vol. 331
LA: English
ER: M (Marine)
AB: The activities of infaunal macrobenthos have major influences on the types, rates and distributions of diagenetic reactions involving manganese in relatively carbon-rich deep-sea and nearshore sediments. In some non-sulphidic hemipelagic deposits of the eastern equatorial Pacific (Panama Basin) biogenic reworking drives internal cycles of manganese, which can apparently account for up to ca. 100% of organic carbon oxidation and reduction of O sub(2) supplied (diffusively) to the sea floor. The occurrence and geometry of manganese oxide encrusted biogenic structures imply specific adaptations of infauna to manganese based microbial activity in hemipelagic sediments like the Panama Basin.
AN: 2423145

                                                                   1210 of 1521  
TI: Bacterial biomass and activity in deep sediment layers from the Peru margin.
AU: Parkes,-R.J.; Cragg,-B.A.; Fry,-J.C.; Herbert,-R.A.; Wimpenny,-J.W.T.
AF: Dep. Geol., Univ. Bristol, Wills Memorial Build., Queen's Rd., Bristol BS8 1RJ, UK
CO: The Deep Sea Bed: Its Physics, Chemistry and Biology. A Discussion, London (UK), 5-6 Apr 1989
SO: THE-DEEP-SEA-BED:-ITS-PHYSICS,-CHEMISTRY-AND-BIOLOGY. Charnock,-H.;Edmond,-J.M.;McCave,-I.N.;Rice,-A.L.;Wilson,-T.R.S.-eds. 1990. vol. 331 pp. 139-153
ST: PHILOS.-TRANS.-R.-SOC.-LOND.,-A. vol. 331
LA: English
ER: M (Marine)
AB: The distribution of bacterial biomass and activity down to 80 m below the sea floor was investigated in sediments from the Peru margin, collected as part of the Ocean Drilling Programme, leg 112. Bacteria were present in all sediment depths sampled. Although direct bacterial counts decreased with depth there was no indication of a more rapid decline in the deeper layers and thus it is likely that bacteria should be present to much greater depths than those examined in this study. A significant number of the bacteria within the sediment were dividing and hence the bacteria were active and not just surviving. Bacteria were able to be cultured in laboratory media, from all depths, further confirming the viability of these organisms in situ. Bacterial sulphate reduction and methanogenesis were measured even in the deepest samples, although there were marked changes in rates with depth. There were also significant changes in the dominant populations of different types of viable bacteria and their associated activity with sediment depth.
AN: 2423104

                                                                   1211 of 1521  
TI: The role of lesser snow geese as nitrogen processors in a sub-arctic salt marsh.
AU: Ruess,-R.W.; Hik,-D.S.; Jefferies,-R.L.
AF: Biol. Res. Lab., 130 College Place, Syracuse Univ., Syracuse, NY 13244, USA
SO: OECOLOGIA. 1989. vol. 79, no. 1, pp. 23-29
LA: English
ER: M (Marine)
AB: Ammonia volatilization losses from faeces of lesser snow geese (Chen caerulescens caerulescens ) were measured during the summer of 1987 on the salt-marsh flats at La Perouse Bay. Amounts of ammonia volatilized increased with increasing ambient temperature, and ranged from 1.0 to 15.1 mg N/100 mg of nitrogen present as soluble ammonium ions at the start of the 8-h experiment. Using estimates of faecal deposition reported previously, the annual loss via volatilization was estimated at 0.08 g N/m super(2), or 7.9% of the nitrogen present in goose faeces. Percent change in soluble ammonium ions in fresh faeces after 8 h ranged from -51.1% to +41.1%, indicating that net mineralization of organic nitrogen occurred in some of the faeces. Microbial respiration of fresh goose faeces increased exponentially with temperature. However, variable rates of net mineralization per unit rate of respiration indicated that the substrate quality affected microbial immobilization and thus net nitrogen mineralization.
AN: 2423103

                                                                   1212 of 1521  
TI: Heterotrophic bacterial populations and primary production in fish ponds under different management practices.
AU: Ayyappan,-S.; Purushothaman,-C.S.; Saha,-P.K.; Pani,-K.C.
AF: Cent. Inst. Freshwater Aquacult., Kausalyagang, Bhubaneswar-751 002, Orissa, India
SO: J.-AQUACULT.-BHUBANESWAR. 1991. vol. 1, pp. 11-29
LA: English
ER: F (Freshwater)
AB: Aerobic heterotrophic bacterial populations in water and sediment and primary production of carp polyculture ponds under different management practices, viz., fortnightly application of cowdung in heaps, spray-application of cowdung on alternate days, gradual leaching of inorganic fertilizers, manual raking of pond bottom and bioturbation by common carp, (Cyprinus carpio ), were studied along with growth of bacterial populations under simulated conditions. Bacterial counts were maximal in ponds with agitated bottom, in spite of absence of allochthonous organic enrichment. Generation time and generation number of the population in the water and sediment media were in the ranges of 0.9-24.8 h, 0.7-21.2 h and 0.2-5.3, 0.2-6.4 resp., indicating intense bacterial activities. Primary production levels in the ponds were moderate (1.13-6.77 g C/m super(3)/d), comprising high (31.27-139.82%) respiration values. Results emphasize the significance of the heterotrophic food chain in fish pond ecosystems and demonstrate the positive effects of simple measures like bottom raking on sediment-water interactions.
AN: 2423077

                                                                   1213 of 1521  
TI: Role of microorganisms in the association of trace elements with particles.
AU: Sunda,-W.G.
AF: Beaufort Lab., Southeast Fish. Cent., NMFS, NOAA, Beaufort, NC 28516, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 82
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: Recent experiments in metal ion buffer systems indicate that the ratio of intracellular to adsorbed extracellular Mn and Zn in photoplankton cells increases dramatically as their free ion concentrations are decreased toward levels thought to exist in seawater. This means that the relative proportion of adsorbed vs intracellular trace metals may change considerably between trace-metal-rich upwelled seawater and depleted oceanic seawater. Trace metal uptake by cells has been shown to be controlled by free ion concentrations of the metal in question as well as those of competing metal ions.
AN: 2420887

                                                                   1214 of 1521  
TI: A need to study interactive effects.
AU: Santschi,-P.H.
AF: EAWAG Swiss Fed. Inst. Technol., 8600 Dubendorf, Zurich, Switzerland
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 81
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: The development of surface chemical models has largely centered on interfacial reactions in well-defined systems. However, the extension of such models to problems of trace element and pollutant cycling has some problematical aspects arising from phYsical and biological "interactive" effects which are, as yet, non-deterministic. Better information on thermodynamic constants is necessary, but not sufficient to reach this goal. This means that surface chemistry has to deal more with interactive effects, such as those arising from trace metal-colloids-large particle interactions, or bacteria-phytoplankton-zooplankton-benthos foodchains, or organic C-trace metal interactions at particle surfaces under the influence of light.
AN: 2420871

                                                                   1215 of 1521  
TI: Important future research for environmental organic chemistry.
AU: Prahl,-F.G.
AF: Sch. Oceanogr., Oregon State Univ., Corvallis, OR 97331, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 117
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: A major proportion of the organic matter synthesized by terrestrial and marine organisms does not survive long after the death of the biological source. Only a few percent is preserved in soils and aquatic sediments as a part of the geological record. On a molecular scale, however, the organic matter synthesized by organisms is not recycled uniformly. Careful study of residual organic molecular fossils preserved in sedimentary records has provided, and will continue to provide, valuable clues, refining our understanding of specific aspects of the C cycle.
AN: 2420028

                                                                   1216 of 1521  
TI: The influence of the sediment community on chemical transformations.
AU: Johnson,-K.S.
AF: Mar. Sci. Inst., Univ. California, Santa Barbara, CA 93106, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 115
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: Geochemical studies of chemical transformations near the sediment-water interface are often characterized by a lack of appreciation for the importance of biological processes. Many of the interesting processes that occur in this region are oxidation- reduction reactions driven by the microbial community. Yet, it is customary for geochemists to ignore the impact of this community on processes occurring within the sediments. The transport of chemicals often occurs due to irrigation of the sediments by macro-organisms. I believe that it is essential for our field to explicitly consider biological processes if we are to obtain accurate models of early diagenesis.
AN: 2420000

                                                                   1217 of 1521  
TI: Chemical and physical characterization of chromophoric organic material.
AU: Zika,-R.G.
AF: Univ. Miami, Rosenstiel Sch. Mar. and Atmos. Sci., Div. Mar. and Atmos. Chem., 4600 Richenbacker Causeway, Miami, FL 33149-1098, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 pp. P. 69
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: Our current understanding of the nature of photochemistry in the ocean indicates that a major portion of the reactions are initiated by the uncharacterized organic chromophores. This material has collectively been given names such as humic substance, Gelbstoffe, heteropolycondensate, or unknown chromophores (UCs). There are believed to be two primary origins for the UCs. One suggests that the material is mostly of riverine origin and exhibits quasi-conservative behavior in the ocean. The other view is that the UCs are formed in situ by autooxidative reactions of plankton-derived organic compounds.
AN: 2419999

                                                                   1218 of 1521  
TI: Coming to grips with the variability of surface water chemistry.
AU: Watson,-A.J.
AF: Mar. Biol. Assoc., Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 105
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: The chemistry of the ocean, particularly the surface layer, is continually changing. The most interesting substances are those which (like nutrients, CO sub(2) and O sub(2)) interact with marine life, and it is precisely those which are most variable. Satellite pictures show that productivity is often highly patchy, with phytoplankton blooms intricately convoluted by mesoscale eddies. Changes are so rapid that there seems little chance of getting a detailed global view of ocean chemistry if we are to be forever limited to taking data from occasional research cruises. One possible way that we might increase the amount of information available, especially about seasonal variations, would be to design chemical instrumentation for mounting on autonomous "data buoys" which could operate untended for months at a time.
AN: 2419993

                                                                   1219 of 1521  
TI: Questions for the modelling group.
AU: Whitfield,-M.; Turner,-D.
AF: Lab., Citadel Hill, Plymouth PL1 2PB, UK
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 pp. 95-96
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AN: 2419986

                                                                   1220 of 1521  
TI: Panel 2: The nature of reactions on marine particle surfaces.
AU: Honeyman,-B.O.; Adamson,-A.W.; Murray,-J.W.
AF: EAWAG, CH-8600, Dubendorf-Zurich, Switzerland
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 pp. 19-26
ST: APPL.-GEOCHEM. vol. 3, no. 1
LA: English
ER: M (Marine)
AB: The subject of this paper--the nature of the reactions at particle surfaces in seawater--was approached in four foci: (1) the distribution of U-Th series isotopes in the oceans and the evidence for scavenging; (2) the problem of organic coatings on surfaces and organic complexation of metals in seawater; (3) the role of metal uptake by marine organisms; and (4) the approaches and problems for modelling marine scavenging.
AN: 2419984

                                                                   1221 of 1521  
TI: Modelling the dynamics of ocean systems.
AU: Whitfield,-M.
AF: Lab., Citadel Hill, Plymouth PL1 2PB, UK
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 94
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: Substantial progress has been made in the development of baseline models for seawater using thermodynamic equilibrium concepts. The application of equilibrium models to marine systems has highlighted many important examples of chemical processes maintained far from equilibrium. The main challenges to the modeller now lie in assessing the dynamics of the system by providing (a) a proper assessment of kinetic controls on chemical processes and (b) an accurate representation of the interaction between biological processes and the chemistry of the oceans.
AN: 2419977

                                                                   1222 of 1521  
TI: Solute-particle and particle-particle reaction in seawater.
AU: Morel,-F.M.M.
AF: Dep. Civ. Eng., Build. 48-423, MIT, Cambridge, MA 02139, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 pp. P. 80
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: Further understanding of marine chemistry of trace elements depends on the elucidation of: (1) the nature of the chemical binding of elements and compounds to the surface of "dead" particles, the thermodynamics and kinetics of that binding, and the factors that control it, (2) the nature of biological surface reactions and uptake mechanisms, their specificity, reversibility and biological finality. (3) the relative role of physical, chemical (aggregation, disaggregation, settling) and biological processes in controlling the fate of marine particles, (4) the potential role of microparticles (say < 0.1  mu m) which are typically analyzed with the soluble phase but have physical-chemical properties of solids and participate in particle-interaction dynamics.
AN: 2419975

                                                                   1223 of 1521  
TI: Key problems in the organic chemistry of marine waters and sediments.
AU: Hedges,-J.I.
AF: Sch. Oceanogr., WB-10, Univ. Washington, Seattle, WA 98195, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 113
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: A variety of fundamental problems remain to be solved concerning processes that affect the origin and fates of organic substances in seawater and marine sediments. The processes themselves range from trace metal scavenging to photochemistry and C cycling. Although the myriad of organic substances involved in these processes can be daunting, this complexity represents a correspondingly large potential source of information that remains almost untapped.
AN: 2419971

                                                                   1224 of 1521  
TI: The nature and reactions of marine surfaces: Unresolved problems.
AU: Hunter,-K.A.
AF: Chem. Dep., Univ. Otago, P.O. Box 56, Dunedin, New Zealand
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 pp. P. 78
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: We have, as yet, very little information on the binding mechanisms responsible for reactive element scavenging by marine particles. We need techniques to study ion-binding by real surfaces under natural conditions in order to resolve this dilemma. The dynamics of the scavenging process are still poorly understood. The physical and electrical properties of small riverine particles are profoundly altered when they enter the sea, with demonstrable effects on particle size and colloidal state, e.g. Fe. What are the factors which determine the rate of particle interaction, and the size and morphology of aggregates? Surface organic films on particles look like being great solvents for organic pollutants. What is the importance of organic scavenging by particles?
AN: 2419952

                                                                   1225 of 1521  
TI: Origin, composition and fate of dissolved organic carbon.
AU: Repeta,-D.J.
AF: Dep. Chem., Woods Hole Oceanogr. Inst., Woods Hole, MA 02543, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 102
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: One of the most important outstanding problems in marine chemistry in which significant advances in our understanding can be achieved through the application of modern chemistry and chemical technology is the origin, composition, and fate of dissolved organic C. Organic C dissolved in seawater constitutes one of the largest potentially "reactive" reservoirs of C on the planet (10 super(18) g C). At present there are no known sinks for dissolved organic C, although photochemical oxidation has been suggested.
AN: 2419951

                                                                   1226 of 1521  
TI: Problems in chemical oceanography and marine chemistry.
AU: Dyrssen,-D.
AF: Dep. Anal. and Mar. Chem., Univ. Goteborg, Goteborg S-412 96, Sweden
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 101
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AN: 2419944

                                                                   1227 of 1521  
TI: The nature of reactions on particle surfaces in seawater.
AU: Fisher,-N.S.
AF: Oceanogr. Sci. Div., Brookhaven Natl. Lab., Upton, NY 11973, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 pp. P. 76
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: One area regarding metal-particle interactions which has received comparatively little study is the degree to which metals, once associated with biogenic particulates, are retained by these particles as they sink through the water column. To what extent can we consider the association of different metals with biogenic debris irreversible? What are the rates of release of different metals from particulate matter, and how are these rates influenced by environmental factors? It is really self-evident that this information would have direct bearing on our understanding of the particle-mediated flux of metals in marine systems.
AN: 2419924

                                                                   1228 of 1521  
TI: What do we need to know about kinetics in marine chemistry?.
AU: Dickson,-A.G.
AF: Mar. Phys. Lab., S-002, Scripps Inst. Oceanogr., La Jolla, CA 92093-0902, USA
CO: CHEMRAWN IV. Modern Chem. and Chem. Technol. Appl. to the Ocean and Its Resources, Keystone, CO (USA), 4-9 Oct 1987
SO: CHEMRAWN-IV.-MODERN-CHEMISTRY-AND-CHEMICAL-TECHNOLOGY-APPLIED-TO-THE-OCEAN-AND-ITS-RESOURCES.-PROCEEDINGS-OF-AN-INTERNATIONAL-CONFERENCE-AND-WORKSHOP-SPONSORED-BY-THE-INTERNATIONAL-UNION-OF-PURE-AND-APPLIED-CHEMISTRY,-HELD-AT-KEYSTONE,-COLORADO,-U.S.A.,-4-9-OCTOBER-1987. Goldberg,-E.D.-ed. 1988. vol. 3, no. 1 p. 88
ST: APPL.-GEOCHEM. vol. 3, no. 1
NT: Summary only.
LA: English
ER: M (Marine)
AB: The oceans comprise a multifaceted chemical environment. A wide variety of chemical, physical, and biological processes occur, each with its own characteristic scales of time and space. It is the interaction between these various processes that fascinates the marine chemist. How should one study such a varied and dynamic system? The identification and measurement of the parameters which control the kinetics of such processes will be a goal of marine chemists for some time.
AN: 2419922

                                                                   1229 of 1521  
TI: CHEMRAWN IV. Modern Chemistry and Chemical Technology Applied to the Ocean and Its Resources. Proceedings of an International Conference and Workshop Sponsored by the International Union of Pure and Applied Chemistry, held at Keystone, Colorado, U.S.A., 4-9 October 1987 (CHEMRAWN IV: An overview).
AU: Goldberg,-E.D.-(ed.); Hitchon,-B.
AF: Appl. Geochem.
CO: CHEMRAWN IV: Modern Chemistry and Chemical Technology Applied to the Ocean and its Resources. Int. Conf. and Workshop, Keystone, CO (USA), 4-9 Oct 1987
SO: APPL.-GEOCHEM. 1988. vol. 3, no. 1, 140 pp
LA: English
ER: M (Marine)
AB: The International Union of Pure and Applied Chemistry (IUPAC), of which the International Association of Geochemistry and Cosmochemistry (IAGC) is an Associated Organization, sponsors a series of conferences with the general title CHEMRAWN, which stands for CHEMical Research Applied to World Needs. Each conference is important, in its own right, to the future well being of mankind. None, however, has the potential global impact on the very existence of the human race as does CHEMRAWN IV, the subject of this issue of Applied Geochemistry. Global change has been the subject of much research in the past decade. It was the recognition of the need to link experts in ocean geochemistry and chemistry that led to CHEMRAWN IV. The conference was structured in a series of five problem areas, each comprising short statements by geochemists and chemists summarizing their perceived needs for research and posing questions for deliberation by panels set up to address the problem areas.
AN: 2419920

                                                                   1230 of 1521  
TI: Nutrient release rates from the sediments of Saginaw Bay, Lake Huron.
AU: Ullman,-W.J.; Aller,-R.C.
AF: Coll. Mar. Stud., Univ. Delaware, Lewes, DE 19958, USA
SO: HYDROBIOLOGIA. 1989. vol. 171, no. 2, pp. 127-140
LA: English
ER: F (Freshwater)
AB: Direct measurements of net production rates and pore water profiles of solutes in the fine-grained sediments of Saginaw Bay, imply corresponding steady-state fluxes to the overlying water of 1.1-1.3 (I), 450-1010 (NH sub(4) super(+)), 1250-2650 (Si(OH) sub(4)), 3000-3400 (Ca super(2+)), 440-1330 (Mg super(2+)), 1.5-728 (Fe super(2+)), and 179-281 (Mn super(2+))  mu moles/m super(2)/day and 11.0-11.8 (alkalinity) meq/m super(2)/day at 17.5 degree C. Silica production rates in sediments apparently follow first order kinetics with a rate coefficient of  similar to 0.09/day and a steady-state silica concentration of 1.2 mM at 23.5 degree C. The remaining solutes follow kinetics approximately independent of solute concentration over the range of concentrations observed. Solute production rates are consistent with observed solute profiles only if lateral diffusion gradients are maintained in the sediments by the burrowing and irrigation activity of benthic organisms such as Chironomous). Extrapolated silica fluxes from Lake Huron sediments balance the estimated biogenic silica flux to the sediments.
AN: 2410786

                                                                   1231 of 1521  
TI: New production at the VERTEX time-series site.
AU: Knauer,-G.A.; Redalje,-D.G.; Harrison,-W.G.; Karl,-D.M.
AF: Univ. South. Mississippi Cent. Mar. Sci., John C. Stennis Space Cent., SSC, MS 39529, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1990. vol. 37, no. 7A, pp. 1121-1134
LA: English
ER: M (Marine)
AB: Particulate organic carbon and nitrogen fluxes measured with free-floating sediment traps deployed six times over an 18-month period were combined with  super(14)C primary production and  super(15)N uptake measurements in order to obtain annual estimates of new production (NP) and associated f-ratios at the VERTEX time-series site. The site, located in the northeast Pacific Ocean at 33 degree N, 139 degree W, was occupied at trimonthly intervals to conduct water column studies and to recover/redeploy the sediment traps. The upper 250 m of the VERTEX site exhibited considerable variability in some biological properties over seasonal time scales. The f-ratio appeared to be inversely related to primary production, with lowest estimates obtained during the period of highest productivity. Values of annual NP derived from various estimates were remarkably similar ranging from 13-17 g C/m super(2)/y. The average annual f-ratio ranged from 0.11 to 0.14.
AN: 2408861

                                                                   1232 of 1521  
TI: Anomalous nutrient distribution in the equatorial Pacific in April 1988: Evidence for rapid biological uptake.
AU: Bender,-M.L.; McPhaden,-M.J.
AF: Grad. Sch. Oceanogr., Univ. Rhode Island, Kingston, RI 02881, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1990. vol. 37, no. 7A, pp. 1075-1084
LA: English
ER: M (Marine)
AB: Nutrients in the central equatorial Pacific are normally enriched at the Equator, with concentrations gradually falling to the north and south. This pattern reflects input by equatorial upwelling, with slow removal as waters flow poleward. In April 1988, we observed minima in SiO sub(2) and NO sub(3-) + NO sub(2-) concentrations near the Equator. (SiO sub(2)) in particular dropped to minima at 2.5 degree N and 1-2.5 degree S, rose to maxima at 3 degree N and 3-6 degree S, then fell off in the normal pattern. Such minima are unusual features not clearly evident in data from other equatorial Pacific transects. A period of anomalous hydrographic conditions preceded the time of our chemical observations. Between February 1988 and April 1988, the anomalously warm conditions which characterized the equatorial Pacific during the 1986-1987 El Nino/Southern Oscillation event ended, and the thermocline shoaled sharply. The authors speculate that the anomalous nutrient distributions we observed in April are related to the regional hydrography of the preceding months. Physical forcing may have triggered rapid biological SiO sub(2) and NO sub(3-) removal, producing the anomalous nutrient distribution we observed.
AN: 2408851

                                                                   1233 of 1521  
TI: Phosphorus metabolism in coral reef communities: Dynamics in the water column.
AU: Sorokin,-Yu.I.
AF: Oceanol. Dep., Gelendzhik-7, Krasnodar District 353470, USSR
SO: AUST.-J.-MAR.-FRESHWAT.-RES. 1990. vol. 41, no. 6, pp. 775-783
LA: English
ER: M (Marine)
AB: Phosphorus dynamics were studied in the coral reef waters of Heron and Wistari Reefs in the Capricornia group, Great Barrier Reef, Australia. All studies were made during August-October 1986. Labelled phosphate (PO sub(4)- super(33)P) was used to measure total uptake as well as uptake by bacterioplankton. Rates of total PO sub(4)-P uptake by microplankton varied between 20 and 120 ng P/L/h at water temperatures of 20-24 degree C. The daily (24 h) uptake rate of PO sub(4)-P was 0 multiplied by 5-3 multiplied by 0  mu g/L. The ambient PO sub(4)-P content of water over the reefs was low (0 multiplied by 03-0 multiplied by 3  mu mol/L, or 1-10  mu g P/L). Turnover time of PO sub(4)-P in the water column of these reef areas is therefore very short, being in the range of 2-8 days, even when its possible net consumption by bottom biota is ignored. Bacterioplankton, not phytoplankton, was found to be the major consumer of inorganic phosphorus in the waters. The results of these estimations are discussed in terms of the importance of active phosphorus dynamics in the water column to the nutrient budget of the coral reef ecosystem.
AN: 2407357

                                                                   1234 of 1521  
TI: Fate of added  super(15)N labelled nitrogen in a Sagittaria lancifolia  L. Gulf Coast marsh.
AU: DeLaune,-R.D.; Lindau,-C.W.
AF: Lab. Wetland Soils and Sediments, Louisiana State Univ., Baton Rouge, LA 70803-7511, USA
SO: J.-FRESHWAT.-ECOL. 1990. vol. 5, no. 3, pp. 265-268
LA: English
ER: F (Freshwater)
AB: Response of Sagittaria lancifolia  L. to added  super(15)N labelled nitrogen was studied in a Louisiana Gulf Coast freshwater marsh. The amount of the added labelled NH sub(4) super(+)-N remaining in the soil or plant tissue was determined several times during the growing season. Above-ground biomass increased by approximately 100 percent following the addition of 10 g NH sub(4) super(+)-N/m super(2). There was no significant nitrogen loss from the soil during the growing season after the labelled inorganic nitrogen was apparently immobilized into the soil organic nitrogen pool.
AN: 2406029

                                                                   1235 of 1521  
TI: A comparison of detritus processing between permanent and intermittent headwater streams.
AU: Richardson,-W.B.
AF: Savannah River Ecol. Lab., Drawer E, Aiken, SC 29801, USA
SO: J.-FRESHWAT.-ECOL. 1990. vol. 5, no. 3, pp. 341-357
LA: English
ER: F (Freshwater)
AB: The pattern of leaf pack decomposition and density and biomass of the associated invertebrate detritivore community of an intermittent and a perennially flowing headwater stream were compared in autumn and spring. Leaf packs of high (Alnus rugosa ) and low (Fraxinus americana ) nitrogen content were used. The intermittent stream had a depauparate shredder fauna and was numerically dominated by collectors. Lack of shredding detritivores, combined with decreased duration of submersion, resulted in reduced potential for processing of particulate carbon relative to the permanently flowing stream.
AN: 2405741

                                                                   1236 of 1521  
TI: Aragonite production by pteropod molluscs in the subarctic Pacific.
AU: Fabry,-V.J.
AF: Chem. Dep., Woods Hole Oceanogr. Inst., Woods Hole, MA 02543, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 11A, pp. 1735-1751
LA: English
ER: M (Marine)
AB: Daily aragonite production of thecosomatous pteropods in the subarctic Pacific was estimated using the instantaneous growth rate and size-frequency methods. At Ocean Sta. PAPA during July 1985, samples for production estimates of two pteropod species, Clio pyramidata  and Limacina helicina , were collected in plankton tows using nets of different mesh sizes (303, 150 and 73  mu m) to include all size classes of pteropods. Estimates of calcium carbonate biomass of C. pyramidata  and L. helicina  were 67 and 155 mg CaCO sub(3)/m super(2), respectively. Based on a model of annual production, pteropod aragonite accounts for 4-13% of the estimated total CaCO sub(3) production of 12-20 g CaCO sub(3)/m super(2)/y. Results of the model suggest that coccolithophorids are the major producers of CaCO sub(3) at Sta. PAPA, contributing 59-77% of the estimated total CaCO sub(3) production.
AN: 2397812

                                                                   1237 of 1521  
TI: Flux of transuranium nuclides and chlorinated hydrocarbons in the northwestern Mediterranean.
AU: Fowler,-S.W.; Ballestra,-S.; Villeneuve,-J.-P.
AF: IAEA, Int. Lab. Mar. Radioact., 19 Ave. Castellans, MC 98000, Monaco
SO: CONT.-SHELF-RES. 1990. vol. 10, no. 9-11 Sep, pp. 1005-1023
LA: English
ER: M (Marine)
AB: The transuranium nuclides, plutonium and americium, and selected chlorinated hydrocarbon compounds have been measured in sediment trap samples, bottom sediments and waters. These measurements have been used to quantify vertical fluxes and elucidate particulate biogeochemical cycles, of these man-made contaminants in the northwestern Mediterranean. Sediment trap experiments in the Gulf of Lions (Lacaze-Duthiers Canyon) have shown that transuranic fluxes are considerably higher in the Gulf of Lions, than those which have been reported for the northeast Pacific; principally this is due to the relatively high mass fluxes in this region of the Mediterranean. Water, surface sediment and sediment trap data indicate that  super(241)Am is being transported downward (via particle settling) more rapidly than  super(239-240)Pu. From direct flux measurement, residence times for  super(239-240)Pu and  super(241)Am in the upper 300 m were computed to be 2.5 and 0.14 years, respectively. Comparison of  super(239-240)Pu concentrations in the water column in 1986, with similar measurements made 5-11 years earlier suggests that fallout input to the Mediterranean has decreased by nearly a factor of 2 during the period 1975-1986.
AN: 2397465

                                                                   1238 of 1521  
TI:  super(210)Po,  super(210)Pb in sediment trap particles on a Mediterranean continental margin.
AU: Heussner,-S.; Cherry,-R.D.; Heyraud,-M.
AF: Lab. Sedimentol. Geochim. Mar., CNRS URA 715, Univ. Perignan, 66025 Perpignan, France
SO: CONT.-SHELF-RES. 1990. vol. 10, no. 9-11, pp. 989-1004
LA: English
ER: M (Marine)
AB: Concentrations of the natural radionuclides  super(210)Po and  super(210)Pb were measured in particulate matter collected in sediment traps, deployed in the Gulf of Lions during the first phase of the ECOMARGE programme (between July 1985 and April 1986). The data obtained are unexceptional in terms of the absolute concentrations measured, but show interesting features in the  super(210)Po/ super(210)Pb activity ratios. These are high (about 6) in samples collected in summer at 50 m depth, they are above unity in all except one of the 50 and 100 m depth samples, and are less than unity in most of the deeper (300 and 600 m) samples. There is a clear tendency for  super(210)Po to covary with organic matter and biogenic silica; likewise, for  super(210)Pb to covary with carbonates and refractory silicates. Particulate matter fluxes and nuclide fluxes into the deep traps were very high in winter. The utility of the  super(210)Po/ super(210)Pb activity ratios, as indicators of the origin of these fluxes, is highlighted.
AN: 2397390

                                                                   1239 of 1521  
TI: Seasonality and composition of particulate fluxes during ECOMARGE-I, western Gulf of Lions.
AU: Monaco,-A.; Courp,-T.; Heussner,-S.; Carbonne,-J.; Fowler,-S.W.; Deniaux,-B.
AF: Lab. Sedimentol. Geochim. Mar., Univ. Perpignan, Ave. Villeneuve, 66025 Perpignan Cedex, France
SO: CONT.-SHELF-RES. 1990. vol. 10, no. 9-11, pp. 959-987
LA: English
ER: M (Marine)
AB: As part of the ECOMARGE program (ECOsystemes de MARGE continentale), sequential sediment traps were deployed on the continental margin of the Gulf of Lions, in the northwestern Mediterranean Sea. Two sites located in the southwestern part of this region were selected for the first phase of the experiment: inner shelf (bottom depth: 27 m) and continental slope (Lacaze-Duthiers Canyon, bottom depth: 650 m). Total mass, organic matter, opal, carbonate and siliciclastic residue fluxes were measured biweekly at 50, 100, 300 and 600 m in the upper part of the Lacaze-Duthiers Canyon (from July 1985 to April 1986) and for longer periods (2 weeks to 2 months) at 10 and 25 m on the shelf (from May 1985 to June 1986). Mass fluxes increased generally with depth, reaching values as high as 20,000 mg m super(-2)/d in the 600 m slope (canyon) trap; this indicated lateral transport of biogenic and abiogenic particulate matter, from local (adjacent shelf and upper slope waters) and distant origin (Rhone River).
AN: 2397344

                                                                   1240 of 1521  
TI: Particle fluxes and ecosystem response on a continental margin: The 1985-1988 Mediterranean ECOMARGE experiment.
AU: Monaco,-A.; Biscaye,-P.; Soyer,-J.; Pocklington,-R.; Heussner,-S.
AF: Lab. Sedimentol. Geochim. Mar., Univ. Perpignan, Ave. Villeneuve, 66025 Perpignan, France
SO: CONT.-SHELF-RES. 1990. vol. 10, no. 9-11, pp. 809-839
LA: English
ER: M (Marine)
AB: The first experiment of the ECOMARGE programme (ECOsystemes de MARGE continentale) was initiated in 1983-1984, in the Gulf of Lions (northwestern Mediterranean Sea). The objectives of the ECOMARGE--I experiment were: to quantify the transfer of particulate matter, in general, and of organic carbon, in particular, from its introduction to and formation in the waters of the continental shelf--to its consumption or sedimentation on the shelf or its transfer to the slope and deep sea; and to understand the processes involved in that transfer, consumption and sedimentation together with their variability in space and time. The results of that experiment, from 1983 to 1988, are presented in this Special Issue. The highlights of the results are summarised in this paper.
AN: 2396907

                                                                   1241 of 1521  
TI: Dissolved titanium in the open ocean.
AU: Orians,-K.J.; Boyle,-E.A.; Bruland,-K.W.
AF: Dep. Oceanogr., Univ. British Columbia, Vancouver, B.C. V6T 1W5, Canada
SO: NATURE. 1990. vol. 348, no. 6299, pp. 322-325
LA: English
ER: M (Marine)
AB: Here we present measurements of titanium profiles in the open ocean. Dissolved titanium is found to be a reactive short-residence-time element, with a unique and highly non-uniform spatial distribution. Dissolved titanium is depleted in surface waters and enriched in deep waters, with a range of more than two orders of magnitude, and there are several indications that it is scavenged (removed by biotic or abiotic processes). This unusual oceanic distribution makes titanium potentially useful as a new tracer of chemical transport processes in deep waters.
AN: 2396826

                                                                   1242 of 1521  
TI: Fluxes and budget of organic matter in the benthic boundary layer over the northwestern Mediterranean margin.
AU: Buscail,-R.; Pocklington,-R.; Daumas,-R.; Guidi,-L.
AF: Lab. Sedimentol. Geochim. Mar., CNRS UA 715, Univ. Perpignan, Ave. de Villeneuve, 66025 Perpignan Cedex, France
SO: CONT.-SHELF-RES. 1990. vol. 10, no. 9-11, pp. 1089-1122
LA: English
ER: M (Marine)
AB: Sediment traps were deployed at depths of 26 and 645 m at 2 stations on the continental margin of the Gulf of Lions (northwestern Mediterranean). During the same period, surficial sediments were sampled by box corer. The material collected by bottom sediment traps and in corresponding surface sediments was analysed for total organic carbon, hydrolysable organic carbon, nitrogen, sugars, amino acids and lignin-derived compounds. Seasonal variations in organic inputs and the difference between particles from bottom layers and sediment were compared.
AN: 2396733

                                                                   1243 of 1521  
TI: Tracers and constituents indicating the nature of organic fluxes, their origin and the effect of environmental conditions.
AU: Gadel,-F.; Puigbo,-A.; Alcaniz,-J.M.; Charriere,-B.; Serve,-L.
AF: Lab. Sedimentol. Geochim, Mar., Ave. Villenueve, Univ. Perpignan, France
SO: CONT.-SHELF-RES. 1990. vol. 10, no. 9-11, pp. 1039-1062
LA: English
ER: M (Marine); B (Brackish)
AB: The nature of particulate organic matter was studied in suspended material sampled by bottles, particles collected by sediment traps and deposits from deltaic and open sea ecosystems of the northwestern Mediterranean. Elemental analyses were combined with pyrolysis-gas chromatography-mass spectrometry and with analysis of individual compounds such as phenols separated by high-performance liquid chromatography. Two marine prodeltas were compared: organic matter was more degraded in suspended material and sediments collected in the submarine delta of the Rhone River. Organic material originating from the river was transported further offshore, as indicated by a higher content of aromatic hydrocarbons and phenols. In the southwestern part of the Gulf of Lions, the prodelta reflected the influence of local rivers, with lower discharges.
AN: 2396685

                                                                   1244 of 1521  
TI: Contribution of the Rhone River to organic carbon inputs to the northwestern Mediterranean Sea.
AU: Cauwet,-G.; Gadel,-F.; Souza-Sierra,-M.M.-de; Donard,-O.; Ewald,-M.
AF: Lab. Sedimentol. Geochim. Mar., URA CNRS 715, Univ. Perpignan, France
SO: CONT.-SHELF-RES. 1990. vol. 10, no. 911, pp. 1025-1037
LA: English
ER: M (Marine)
AB: Particulate and dissolved organic carbon were determined in coastal waters of the Gulf of Lions, during several cruises from 1986. The input by the Rhone River and its seasonal variability are studied and new data are given concerning the contribution to the Mediterranean Sea. Fluorescence measurements show the limited influences on the open sea of surface particulate matter, but suggest a bottom transport during which diagenetic evolution can occur. The remobilization of dissolved organic matter is also stressed.
AN: 2396684

                                                                   1245 of 1521  
TI: Release of extracellular organic carbon from phytoplankton: An experimental approach.
AU: Riemann,-B.
AF: Int. Agency 14C Determination, Water Qual. Inst., Agern Alle 11, DK-2970 Hoersholm, Denmark
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 p. 35
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: Traditionally, measurements of extracellular release of organic carbon (EOC) from phytoplankton is measured by means of 14C-technique. It is proposed to utilize growth of aquatic bacteria as markers of exudation from phytoplankton in laboratory experiments in which phytoplankton is the only carbon source for the bacteria. Batch cultures of natural populations of freshwater bacteria were diluted in a mixture of inorganic medium + EOC from cultures of exponentially growing freshwater phytoplankton. The algae were grown in inorganic medium. The bacteria were mixed with various concentrations of algae, and bacterial production and increase in cell number were measured during periods of 72 h and compared with algal biomass, cell, surface and cell volume. Bacterial production always covaried with algal biomass suggesting a close coupling between algal biomass and release of EOC. Moreover, in most experiments, algal photosynthesis was positively correlated to bacterial production.
AN: 2387559

                                                                   1246 of 1521  
TI: Phytoplankton exudation: Income tax or property tax?.
AU: Bjoernsen,-P.K.
AF: Mar. Biol. Lab., Univ. Copenhagen, Strandpromenaden 5, DK-3000 Helsingoer, Denmark
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 p 33
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: A considerable proportion of phytoplankton primary production is exudated as dissolved organic matter and rapidly utilised by bacterioplankton. The exudation is traditionally interpreted as an active release of photosynthesis in periods of nutrient stress when carbon fixation is faster than biomass build-up. This "overflow" hypothesis is criticized in an ecological and physiological context. An alternative hypothesis is presented, that a major part of the exudation can be explained as a passive diffusion of low molecular weight organic compounds through the algal cell membrane. This "leakage" hypothesis is supported by a theoretical calculation from data on lipid bilayer membrane permeability to organic molecules and by literature data from field observations and laboratory experiments. The ecological and methodological implications of the two hypotheses are discussed.
AN: 2387533

                                                                   1247 of 1521  
TI: Microbial interactions during decomposition of Phragmites  litter.
AU: Gunatilaka,-A.; Mendez,-M.C.; Herndl,-G.
AF: Inst. Zool., Univ. Vienna, Althanstr. 14, A-1090 Vienna, Austria
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 p. 127
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: P. australis  is the most important emergent macrophyte in the littoral zone of Neusiedlersee, contributing to > 99% of the vegetation cover (178 km super(2)), serving as the major source of organic detritus input into the lake ecosystem. Information available on the role of microbes in the decomposition of Phragmites litter is scarce. The initial phase of the microbial succession was followed in laboratory incubation experiments. Free-living bacterial biomass (as determined by AODC) increased about by one order of magnitude within the first day. Thereafter, nanoflagellates entered exponential growth resulting in a decline in the free-living bacterial population. While the free-living microbial (heterotrophic bacteria + nanoflagellates) community exhibited typical prey-predator oscillations in abundance, the attached microbial community showed a more complex colonization pattern. The initial colonizers of Phragmites litter were coccoid bacteria with a mean volume similar to that of the free-living counterpart.
AN: 2387024

                                                                   1248 of 1521  
TI: Assimilation of free monosaccharides and amino acids relative to bacterial production in eutrophic lake water.
AU: Joergensen,-N.O.G.
AF: Inst. Microbiol., R. Vet. and Agric. Univ., Rolighedsvej 21, DK-1958 Frederiksberg C, Denmark
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 pp. 99-110
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
LA: English
ER: F (Freshwater)
AB: Bacterial assimilation of dissolved free glucose, fructose and amino acids was studied in two eutrophic lakes and in a laboratory experiment. Assimilation rates were related to the actual bacterial production. Natural concentrations of free fructose in the lakes were measured combining separation by HPLC with a post-column colour reaction of the saccharides. Free amino acids were quantified as fluorescent derivatives. Concentrations of free glucose, fructose and amino acids in the lakes were 33-95 nM, 7-55 nM and 6-34 nM, respectively. Assimilation (respiration + incorporation) of the organic compounds on the average sustained 6.7, 11 and 61% of the bacterial carbon requirement. Glucose was the predominant compound assimilated, followed by either fructose or amino acids. A large production of both monosaccharides and amino acids occurred during the experiments. Generally the bacterial production varied independently of concentrations and assimilation rates of the tested organic compounds.
AN: 2386946

                                                                   1249 of 1521  
TI: Measurement of exoenzymatic activity in streambed sediments using methylumbelliferyl-substrates.
AU: Marxsen,-J.
AF: Limnol. Flussstn., Max-Planck-Inst. Limnol., Postfach 260, D-6407 Schlitz, FRG
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Witzel,-K.-P.;Straskrabova,-V.-ed. 1990. no. 34 pp. 21-28
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
LA: English
ER: F (Freshwater)
AB: 4-Methylumbelliferyl-substrates were used to measure the activity of extracellular  beta -D-glucosidase and phosphatase in small central European streams. The substrates could be used for stream water, sandy sediments, and coarser artificial substrata. Although  beta -D-glucosidase activity per unit surface area was about ten times higher in coarse particulate sediments than in sandy sediments, maximum activity per unit volume was observed in sandy sediments. This means that for the stream as a whole, the greater proportion of the exoenzymatic cleavage activity occurs in the sandy streambed deposits.
AN: 2386935

                                                                   1250 of 1521  
TI: Microorganisms in marine sediments: Considerations concerning activity measurements.
AU: Meyer-Reil,-L.-A.
AF: Inst. Oceanol., Univ. Kiel, Duesternbrooker Weg 20, D-2300 Kiel, FRG
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 pp. 1-6
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
LA: English
ER: M (Marine)
AB: The measurement of microbial activities in marine sediments suffers from both an insufficient consideration and knowledge of benthic microbial life characteristics and an uncritical application of methods to the sediment environment. This paper illustrates that sediments are highly complex environments, the activity of which is based on the extracellular enzymatic decomposition of particulate organic material. The information available calls for the use of undisturbed sediments in activity measurements and a critical application of methods. Furthermore, new approaches are needed to follow microbial activity responses in the sediment environment.
AN: 2386931

                                                                   1251 of 1521  
TI: Production and utilization of organic matter by microplankton in an eutrophic lake.
AU: Siuda,-W.; Wcislo,-R.
AF: Dep. Environ. Microbiol., Univ. Warsaw, Karowa 18, 00-325 Warsaw, Poland
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 pp. 67-73
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
LA: English
ER: F (Freshwater)
AB: Production and utilization of photosynthetic organic matter were studied in the pelagic zone of highly eutrophicated Lake Mikolajskie, Mazurian Lake District, Poland.  similar to 97% of the total fixed  super(14)CO sub(3) (TFC) was incorporated photosynthetically by algal cells, and 3% was fixed by microplankton in darkness. In the course of photosynthesis  similar to 20% of TFC was released into the water,  similar to 10% and 70% of TFC was respired and remained in microplankton particulate fraction (POC), respectively. The chemical composition of POC produced was strongly dependent upon light conditions during photosynthesis. Radiocarbon was mainly incorporated into water soluble low molecular weight compounds (LMWC) and polysaccharide fractions. The increased contribution of proteins and lipids to POC was found when algal photosynthesis was light limited. Released organic carbon and the LMWC fraction of POC were preferentially utilized by aquatic bacteria. Supplementation of water samples with LMWC stimulated the bacterial growth rates and production.
AN: 2386871

                                                                   1252 of 1521  
TI: A numerical model of phosphorus exchange between the sediments and the near-bottom water in a lake.
AU: Mitraszewski,-P.; Uchmanski,-J.
AF: Lab. Med. Phys., Inst. Exp. Phys., Warsaw Univ., Hoza 69, 00-681 Warsaw, Poland
SO: EKOL.-POL. 1989. vol. 36, no. 3-4, pp. 317-346
LA: English
ER: F (Freshwater)
AB: A model describing phosphorus exchange between the sediments and the near-bottom water in a lake has been presented. The effect has been considered of bottom animals (Chironomidae and Tubificidae), through their respiratory activity, on this process. It has been found that: (a) under anaerobic conditions the model is more sensitive to parameter variation, (b) estimated by sensitivity analysis of the model, the proportion of phosphorus released by benthonic organisms comes up to 30%, (c) the role of Chironomidae larvae in phosphorus release from sediments is greater than that of Tubificidae.
AN: 2386867

                                                                   1253 of 1521  
TI: Production and respiration of free-living bacterioplankton in a eutrophic lake.
AU: Bell,-R.T.
AF: Inst. Limnol., Uppsala Univ., S-75122 Uppsala, Sweden
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 p. 171
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: Although measurements of heterotrophic bacterial production have proliferated during the past decade, estimates of the total carbon flux (i.e. - including respiration) through the bacterioplankton are fewer. Bacterioplankton production (thymidine method), total plankton respiration and bacterioplankton (< 1-  mu m size fraction) respiration (ETS method calibrated against the Winkler oxygen method; R:ETS = 0.9 for bacteria and 0.26 for total plankton) were measured from May to September, 1987 in hyper-eutrophic Lake Vallentunasjoen, Sweden. Bacterial production ranged from 1-6  mu g C/l/h, and bacterial respiration from ca 1.5 to 11  mu g C/l/h. The bacterial carbon conversion efficiency ranged from 10-50%, averaging 32% and was significantly correlated with the bacterial growth rate. Respiration by the < 1-  mu m size fraction was from 20-70% of total plankton respiration.
AN: 2386753

                                                                   1254 of 1521  
TI: Group report. How do organic acids interact with solutes, surfaces, and organisms?.
CO: Dahlem Workshop on Organic Acids in Aquatic Ecosystems, Berlin (FRG), 7-12 May 1989
SO: ORGANIC-ACIDS-IN-AQUATIC-ECOSYSTEMS.-REPORT-OF-THE-DAHLEM-WORKSHOP-ON-ORGANIC-ACIDS-IN-AQUATIC-ECOSYSTEMS.-BERLIN-1989,-MAY-7-12. Perdue,-E.M.;Gjessing,-E.T.-eds. 1990. pp. 223-243
ST: LIFE-SCI.-RES.-REP.
LA: English
AB: An examination is made of interactions that influence the temporal and spatial variability of organic acids in aquatic ecosystems. Organic acids can interact with different species of organisms, with other solutes such as cations and metals and with particulate surfaces. Those interactions relevant to water quality, such as eutrophication, acidification and drinking water treatment are discussed in particular.
AN: 2386721

                                                                   1255 of 1521  
TI: Compositional indicators of organic acid sources and reactions in natural environments.
AU: Hedges,-J.
AF: Sch. Oceanogr., WB-10, Univ. Washington, Seattle, WA 98195, USA
CO: Dahlem Workshop on Organic Acids in Aquatic Ecosystems, Berlin (FRG), 7-12 May 1989
SO: ORGANIC-ACIDS-IN-AQUATIC-ECOSYSTEMS.-REPORT-OF-THE-DAHLEM-WORKSHOP-ON-ORGANIC-ACIDS-IN-AQUATIC-ECOSYSTEMS.-BERLIN-1989,-MAY-7-12. Perdue,-E.M.;Gjessing,-E.T.-eds. 1990. pp. 43-63
ST: LIFE-SCI.-RES.-REP.
LA: English
AB: Both bulk chemical measurements (e.g., elemental, isotopic, and spectral analyses) and molecular tracers (biomarkers) can be used to determine the sources and reaction histories of organic acids in natural environments. This paper reviews selected characterization methods of these 2 types and critically evaluates their strengths and weaknesses. Finally, research directions are suggested that might lead to more accurate and sensitive procedures for determining the sources and pathways of organic acids in natural environments.
AN: 2386675

                                                                   1256 of 1521  
TI: Marine amorphous aggregates (marine snow) as a model system of the "microbial loop".
AU: Herndl,-G.J.
AF: Inst. Zool., Univ. Vienna, Althanstr. 14, A-1090 Vienna, Austria
CO: 4. Int. Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Ceske Budejovice (Czechoslovakia), 1988
SO: PROCEEDINGS-OF-THE-FOURTH-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Straskrabova,-V.-ed. 1990. no. 34 p. 265
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 34
NT: Summary only.
LA: English
ER: M (Marine)
AB: In the Northern Adriatic Sea, marine snow dry mass varied between 3.4-9.1 mg/l; mean total carbohydrate (TCHO) content of marine snow ranges from 200-800  mu g TCHO/ml (marine snow). TCHO in marine snow was found to be enriched by a factor (EF) of 304 as compared to the surrounding water (x@u- = 0.82  mu g TCHO/ml). The microhererotrophic community in marine snow was dominated by bacteria, choanoflagellates and monads. (EF: 1.3-290). O sub(2)-flux measurements revealed that 90% of the pelagic gross primary production and  similar to 70% of the mineralization activity is bound to marine snow during summer. Batch cultures with marine snow were designed to investigate the influence of marine snow on the free-living microbial community. The degree of the development of the microheterotrophic food chain was quantified using the ratio (nanoflagellate biomass/bacterial biomass) x 100. Ratios of > 100 were maintained most of the time, suggesting that additional food sources other than free-living bacteria were exploited by the nanoflagellates population.
AN: 2386600

                                                                   1257 of 1521  
TI: Simulation model of phosphorus cycling in the epilimnion of a eutrophic lake.
AU: Uchmanski,-J.
AF: Inst. Paleobiol., Pol. Acad. Sci., Al. Zwirki i Wigury 93, 02-089 Warsaw, Poland
SO: EKOL.-POL. 1989. vol. 36, no. 3-4, pp. 347-386
LA: English
ER: F (Freshwater)
AB: The model describes time-related changes in six variables: concentration of dissolved orthophosphate phosphorus P-PO sub(4), phytoplankton, bacteria, detritus, non-predatory zooplankton, and predatory zooplankton in the epilimnion of Lake Glebokie, Poland. The stability of the model was analysed, and it has been found that the variables show damped oscillations around equilibrium points. Results of numerical experiments are presented, simulating a cessation of fish farming in the lake, changes in the level and timing of phosphorus inflow to the epilimnion from deeper layers of the lake, and changes in temperature and light conditions. The results show that the inflow of phosphorus from deeper layers largely influences the values of the model variables.
AN: 2383085

                                                                   1258 of 1521  
TI: Methods for improving the efficiency of calibration of a model of phosphorus cycling in a lake ecosystem.
AU: Loga,-M.
AF: Inst. Environ. Eng., Warsaw Tech. Univ., Nowowiejska 20, 00-653 Warsaw, Poland
SO: EKOL.-POL. 1989. vol. 36, no. 3-4, pp. 387-406
LA: English
ER: F (Freshwater)
AB: The author describes methods for improving the efficiency of calibration of a model of phosphorus cycling in a lake ecosystem. The traditional trial and error method is not an efficient tool for estimating the parameters of ecological models. The degree of complication of a typical ecological model also makes it impossible to use available formal algorithms. Two techniques can, however, be suggested which considerably improve the process of parameter estimation. One of them is the method of step by step merging subsequent state equations, and the other that of aiding the estimation process with sensitivity analysis.
AN: 2382864

                                                                   1259 of 1521  
TI: Alkylmercury species in the Equatorial Pacific.
AU: Mason,-R.P.; Fitzgerald,-W.F.
AF: Dep. Mar. Sci., Univ. Connecticut, Avery Point, Groton, CT 06340, USA
SO: NATURE. 1990. vol. 347, no. 6292, pp. 457-459
LA: English
ER: M (Marine)
AB: We now report evidence of monomethyl and dimethyl mercury in the low-oxygen waters of the Equatorial Pacific. The presence of these species has important implications for our understanding of the biogeochemical cycling of mercury in the marine environment. Although the source of monomethyl mercury in open-ocean fish is still unknown, our data show that a pathway exists for the accumulation of methylated mercury in marine pelagic fish.
AN: 2382786

                                                                   1260 of 1521  
TI: Estimation of forms of phosphorus in the Venoge River during storm events.
OT: Estimation des formes du phosphore dans la riviere Venoge en crue
AU: Zhang,-L.; Gregor,-D.J.; Vernet,-J.P.
AF: Inst. F.A. Forel, Univ. Geneva, 10 Route de Suisse, CH-1290 Versoix, Switzerland
CO: 2. Conf. Int. des Limnologues d'Expression Francaise, Aussois (France), 24-28 May 1988
SO: REV.-SCI.-EAU. 1989. vol. 2, no. 4, pp. 709-720
LA: French
ER: F (Freshwater)
AB: To gain a better understanding of phosphorus transport in a storm-dependent river system, water samples were collected near the mouth of the River Venoge, Switzerland, during 5 storm events. A multivariate progressive analysis of the measured P data set shows that total particulate P (TPP) can be estimated as a function of two parameters, the % of a suspended sediment (SS) fraction coarser than 63  mu m and the soluble reactive phosphorus (SRP) concentration measured in filtered water. On the other hand, general statistical relationships exist between the various forms of phosphorus. Total soluble phosphorus (TSP) is dependent upon SRP. Organic phosphorus (OP) and non-apatite inorganic phosphorus (NAIP) can be approximately assessed from TPP, measured or calculated. Then, apatite phosphorus (AP), inorganic phosphorus (IP) and total phosphorus in raw water can be calculated by means of summation/substraction operations.
AN: 2379637

                                                                   1261 of 1521  
TI: Responses in bacterial activity to changing conditions in plankton -- probable controlling mechanisms.
AU: Simek,-K.; Fuksa,-J.K.
CO: Int. Conf. on Reservoir Limnology and Water Quality, Ceske Budejovice (Czechoslovakia), 15 Jun 1987
SO: PROCEEDINGS-OF-THE-INTERNATIONAL-CONFERENCE-ON-RESERVOIR-LIMNOLOGY-AND-WATER-QUALITY.-1.-PHYSICAL-LIMNOLOGY,-MATHEMATICAL-MODELS-AND-MICROBIAL-DECOMPOSITION. Henderson-Sellers,-B.;Straskrabova,-V.-eds. 1989. no. 33 pp. 239-248
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 33
LA: English
ER: F (Freshwater)
AB: Parameters of total activity of bacterioplankton were determined by means of  super(14)C-glucose uptake (V sub(max)) and the incorporation of tritiated amino acids (AA). Parameters of individual activity were determined by the autoradiographic method using AA (% of metabolizing cells) and  super(3)H-thymidine (% of "probably dividing" cells) during both seasonal and diel cycles. A close relationship was found between microbial activity and the diel cycle of photosynthesis. On a seasonal time-scale, significant relationships were found between counts of metabolizing bacteria and phytoplankton biomass. The relationship between the former and the biomass of Cladocera) was even more significant.
AN: 2379309

                                                                   1262 of 1521  
TI: Vertical distribution of planktonic bacteria and its seasonal changes in a shallow reservoir.
AU: Markosova,-R.; Benediktova,-M.; Volkova,-A.
CO: Int. Conf. on Reservoir Limnology and Water Quality, Ceske Budejovice (Czechoslovakia), 15 Jun 1987
SO: PROCEEDINGS-OF-THE-INTERNATIONAL-CONFERENCE-ON-RESERVOIR-LIMNOLOGY-AND-WATER-QUALITY.-1.-PHYSICAL-LIMNOLOGY,-MATHEMATICAL-MODELS-AND-MICROBIAL-DECOMPOSITION. Henderson-Sellers,-B.;Straskrabova,-V.-eds. 1989. no. 33 p. 257
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 33
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: The authors tried to find a correlation between seasonal changes of vertical distribution of planktonic bacteria and the fluctuations of the organic material in the water column. In the Hostivar reservoir (up to 130  mu g/l chlorophyll-a) the phytoplankton should be considered as a main source of organic bacterial nutrients. Seasonal changes in heterotrophic mesophilic bacteria, coliform bacteria, faecal streptococci and direct counts of bacteria were studied during two following seasons. The results were compared with fluctuations of temperature, oxygen and ammonium content, chlorophyll-a concentration, BOD sub(1) and BOD sub(5). The vertical distribution revealed maximum counts at a maximal depth 7 metres: 8.8 x 10 super(6) cells/ml. The epilimnial bacterial counts correlated with those of the phytoplankton, whereas bacterial counts in the hypolimnion were in a correlation with ammonium nitrogen. Phytoplankton was identified as a main source of organic nutrients in the reservoir. The contribution to the total nutrient pool was calculated to be 44 and 57% in 1982 and 1983, respectively.
AN: 2379241

                                                                   1263 of 1521  
TI: Bacterial utilization of photosynthetically produced dissolved and particulate organic matter and the role in C-flux of Lake Stechlin.
AU: Babenzien,-C.; Babenzien,-H.-D.
CO: Int. Conf. on Reservoir Limnology and Water Quality, Ceske Budejovice (Czechoslovakia), 15 Jun 1987
SO: PROCEEDINGS-OF-THE-INTERNATIONAL-CONFERENCE-ON-RESERVOIR-LIMNOLOGY-AND-WATER-QUALITY.-1.-PHYSICAL-LIMNOLOGY,-MATHEMATICAL-MODELS-AND-MICROBIAL-DECOMPOSITION. Henderson-Sellers,-B.;Straskrabova,-V.-eds. 1989. no. 33 pp. 225-235
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 33
LA: English
ER: F (Freshwater)
AB: The aim of this study was to quantify the microbial capacity in relation to primary production in C-flux of oligotrophic Lake Stechlin. Primary production, exudation, and bacterial assimilation of exudates were measured with the  super(14)C-method and a particle size fractionation technique. Production of  super(14)CO sub(2) was employed as an estimate of the mineralization rate. With natural phytoplankton populations average exudation rates of 50% in the oligotrophic Lake Stechlin and 20% in the eutrophic Lake Dagow were obtained. On average 20% and 8% of the primary production respectively was assimilated by the bacterial population in the two lakes. 40 to 90% of the bacterial production was based on the utilization of exudates.
AN: 2378113

                                                                   1264 of 1521  
TI: Oxygen and nitrate new production and remineralization in the North Atlantic subtropical gyre.
AU: Sarmiento,-J.L.; Thiele,-G.; Key,-R.M.; Moore,-W.S.
AF: Atmos. and Oceanic Sci. Program, Princeton Univ., Princeton, NJ 08540, USA
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1990. vol. 95, no. C10, pp. 18303-8315
LA: English
ER: M (Marine)
AB: New estimates are obtained of oxygen utilization rates on isopycnal surfaces in the North Atlantic subtropical gyre thermocline based on tritium inventories (2.4-3.5 mol m super(-2)/yr) and  super(228)Ra measurements (8.5  plus or minus  0.8 mol m super(-2)/yr). Arguments are given for why the tritium inventory oxygen utilization rate estimate may be too low. The  super(228)Ra results are combined with recent estimates of oxygen utilization within the thermocline as well as estimates of oxygen production in the mixed layer, to suggest a tentative overall oxygen balance for the whole water column.
AN: 2375509

                                                                   1265 of 1521  
TI: Abiotic transformations of iron and phosphate in humic lake water revealed by double-isotope labeling and gel filtration.
AU: Jones,-R.I.; Salonen,-K.; de-Haan,-H.
AF: Div. Biol. Sci., Inst. Environ. and Biol. Sci., Univ. Lancaster, Lancaster LA1 4YQ, UK
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 491-497
LA: English
ER: F (Freshwater)
AB: Abiotic transformations of Fe and PO sub(4) super(3-) in humic water from Finnish forest lakes were studied by Sephadex G-100 gel filtration following incubation of filtered (0.2  mu m) epilimnetic water samples to which both  super(55)FeCl sub(3) multiplied by 6H sub(2)O and  super(32)PO sub(4) super(3-) had been added. The simultaneous movement of  super(55)Fe and  super(32)P to higher molecular-weight fractions (10,000-20,000 MW) depended on the presence of dissolved humic substances (DHS). In the absence of DHS almost all  super(55)Fe, probably as inorganic hydrolyzed iron particles, sorbed to the Sephadex. In the absence of quasi-equilibrium between free and DHS-bound  super(32)PO sub(4) super(3-), the DHS-Fe-PO sub(4) super(3-) complex readily released  super(32)PO sub(4) super(3-)-P. Compared to the  super(32)P binding,  super(55)Fe binding was rapid. More than 20% of the Fe had been bound after only 1 min, whereas for labeled PO sub(4) super(3-) this percentage was reached only after 24 h.
AN: 2368760

                                                                   1266 of 1521  
TI: Algal use of sedimentary phosphorus from an Amazon floodplain lake: Implications for total phosphorus analysis in turbid waters.
AU: Engle,-D.L.; Sarnelle,-O.
AF: Dep. Biol. Sci., Univ. California, Santa Barbara, CA 93106, USA
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 483-490
LA: English
ER: F (Freshwater)
AB: Chemical forms of P and and their availabilities to Selenastrum capricornutum  were measured in sediments collected from Lago Calado, an Amazon floodplain lake. Postbioassay analysis confirmed that Selenastrum  used  similar to 60-70% of the P in the NaOH-extracted fraction during a 9-d incubation. No evidence for algal use of Ca-bound P or organic P was found. Methodological comparisons revealed that persulfate digestion may not adequately recover algal-available particulate P in waters high in inorganic turbidity. An average of 26% of the algal-available P in Amazon River water was in particulate form.
AN: 2368606

                                                                   1267 of 1521  
TI: Biogeochemistry of carbon in the Amazon River.
AU: Richey,-J.E.; Hedges,-J.I.; Devol,-A.H.; Quay,-P.D.; Victoria,-R.; Martinelli,-L.; Forsberg,-B.R.
AF: Sch. Oceanogr. and Quaternary Res. Cent., Univ. Washington, Seattle, WA 98195, USA
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 352-371
LA: English
ER: F (Freshwater)
AB: Depth-integrated, discharge-weighted water samples were collected over 1,800 km of the Amazon River on 8 cruises at different stages of the hydrograph, 1982-1984. Fine (FPOC, < 63  mu m) and coarse (CPOC, > 63  mu m) particulate organic carbon as weight percentage of suspended sediment varied between 0.9-1.5% for FPOC and 0.5-3.4% for CPOC. Concentrations of FPOC ranged from 5 mg/liter upriver to 2 mg/liter downriver in the mainstem and from 6 mg/liter in the Rio Madeira to < 1 in the Rio Negro. CPOC had similar distribution patterns, but with concentrations 15-30% those of FPOC. Dissolved organic carbon (DOC) average 4-6 mg/liter in the mainstem and up to 12 mg/liter in the Rio Negro. Upriver dissolved inorganic carbon (DIC) concentrations of about 1,200  mu M were diluted by tributaries and floodplain drainage to 600  mu M at the most downriver site.
AN: 2367693

                                                                   1268 of 1521  
TI: Diel cycles in microbial manganese oxidation and manganese redox speciation in coastal waters of the Bahama Islands.
AU: Sunda,-W.G.; Huntsman,-S.A.
AF: NMFS, NOAA, Southeast Fish. Cent., Beaufort Lab., Beaufort, NC 28516-9722, USA
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 325-338
LA: English
ER: M (Marine)
AB: We observed pronounced diel cycles in formation rates of particulate Mn in coastal waters of the Bahama Islands. Specific rates during the day were 1/20th-1/70th of maximum nighttime rates and there was an associated 3-5-fold decrease in the ratio of particulate to dissolved Mn during the day. The strong suppression of rates after sunrise probably results from photoinhibition of microbially catalyzed Mn(II) oxidation. The decrease in Mn(II) oxidation during the day along with photodissolution of Mn oxides observed in previous investigations appear to contribute to the increased ratio of dissolved Mn to particulate Mn oxides during daylight.
AN: 2367630

                                                                   1269 of 1521  
TI: Microbial biomass in the coastal plume of Chesapeake Bay: Phytoplankton-bacterioplankton relationships.
AU: Malone,-T.C.; Ducklow,-H.W.
AF: Horn Point Environ. Lab., Univ. Maryland Syst., Cent. Environ. and Estuarine Stud., P.O. Box 775, Cambridge, MD 21613, USA
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 296-312
LA: English
ER: M (Marine); B (Brackish)
AB: Turnover rate of suspended organic matter (POC) increased seasonally with temperature as the proportions of POC accounted for by bacterioplankton increased relative to phytoplankton. The proportion of phytoplankton productivity that cycled through bacterioplankton averaged 13% and showed little seasonal variability. These results imply changes in the pathways and rates by which phytoplankton and bacterioplankton production were consumed or exported from the plume. Time series of 1-3 d next to surface drifters within the plume provided some insight into the nature of these changes. In February when the turnover rate of POC was low, phytoplankton biomass declined relative to bacterioplankton due to sedimentation of large diatoms. Low bacterioplankton biomass was associated with high rates of predation by heterotrophic microflagellates. In August when POC was turning over rapidly, phytoplankton biomass declined relative to bacterioplankton due to selective grazing by copepods.
AN: 2367576

                                                                   1270 of 1521  
TI: Estimation of ammonification and ammonium assimilation in surficial coastal and estuarine sediments.
AU: Sumi,-T.; Koike,-I.
AF: Chikushigaoka High Sch., 2-13-1 Noma Minami-ku Fukuoka, 815, Japan
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 270-286
LA: English
ER: M (Marine); B (Brackish)
AB: Ammonification and NH sub(4) super(+) assimilation is slurries of surface sediments from Japanese coastal and estuarine areas were studied with  super(15)NH sub(4) super(+) tracers. In completely aerobic sediments, where NO sub(3) super(-) reduction is negligible, the Blackburn  super(15)NH sub(4) super(+) dilution model can be applied to estimate the ammonification rate after a correction for nitrification is made. In semiaerobic sediments, where significant NO sub(3) super(-) reduction occurs, a mathematical model based on the change of  super(15)NH sub(4) super(+) and  super(15)NO sub(3) super(-) with time was successfully applied to estimate the ammonification rate. The rate of NH sub(4) super(+) assimilation can be obtained directly from the incorporation of  super(15)NH sub(4) super(+) into particles in the sediments after correcting for  super(15)NH sub(4) super(+) dilution during incubation. The rate of ammonification ranged from 5.8 to 220 ng-atoms N (g sediment) super(-1)/h and that of NH sub(4) super(+) assimilation ranged from 6.2 to 114, indicating both large seasonal and local variations. Both NH sub(4) super(+) assimilation and ammonification were significantly correlated with ATP biomass, NH sub(4) super(+), and organic N contents in sediments.
AN: 2367263

                                                                   1271 of 1521  
TI: Rapid ammonium cycling and concentration-dependent partitioning of ammonium and phosphate: Implications for carbon transfer in planktonic communities.
AU: Suttle,-C.A.; Fuhrman,-J.A.; Capone,-D.G.
AF: Mar. Sci. Inst., Univ. Texas at Austin, P.O. Box 1267, Port Aransas, TX 78373-1267, USA
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 424-433
LA: English
ER: M (Marine)
AB: A short-lived radioactive isotope of nitrogen ( super(13)N, half-life = 10 min) of very high specific activity (> 100 mCi/ mu mol) was used to study NH sub(4) super(+) uptake at near-ambient concentrations in natural planktonic communities. The turnover times of the dissolved NH sub(4) super(+) pool in Long Island Sound ranged from tens of hours between April and early June to a fraction of an hour between mid-June and late July. Up to 50% of the ambient NH sub(4) super(+) flux into particulate material from Long Island Sound was attributable to organisms passing 1.0- mu m polycarbonate filters. Partitioning of NH sub(4) super(+) uptake among size classes was, however, very concentration-dependent. A 0.5  mu M addition resulted in an increase in NH sub(4) super(+) uptake by the > 3- mu m size class of from 33% to > 80% of the total. Because slight increases in NH sub(4) super(+) and PO sub(4) super(3-) concentration result in greater uptake by larger organisms with higher C:N and C:P ratios, distributing these nutrients in "patches" of elevated concentration results in more C being transferred to higher level consumers.
AN: 2367244

                                                                   1272 of 1521  
TI: Variations in sedimentary carbon remineralization rates in the White Oak River estuary, North Carolina.
AU: Kelley,-C.A.; Martens,-C.S.; Chanton,-J.P.
AF: Curric. Mar. Sci., 12-5 Venable Hall CB 3300, Univ. North Carolina, Chapel Hill, NC 27599-3300, USA
SO: LIMNOL.-OCEANOGR. 1990. vol. 35, no. 2, pp. 372-383
LA: English
ER: B (Brackish)
AB: Rates of microbially mediated sedimentary organic carbon remineralization vary along the salinity gradient of the White Oak Estuary. A direct comparison of two sites, one upriver dominated by methanogenesis and one downriver dominated by sulfate reduction, indicates a more rapid rate of remineralization upriver. The uncertainties in the yearly fluxes are calculated from observed in duplicate flux measurements. About 43% of the incoming organic C is remineralized at both sites. The greater remineralization upriver, of which 47% can be attributed to methanogenesis, appears to be supported by rapid decomposition of detritus derived from freshwater, emergent and submersed macrophytes. The high organic C content of these upriver sediments may, however, result from the long-term storage of slower degrading plants.
AN: 2367188

                                                                   1273 of 1521  
TI: Controls on surface water chemistry in the southern Blue Ridge and Piedmont Provinces.
AU: Stauffer,-R.E.
AF: 3633 Humphrey Lane, Lexington, KY 40502, USA
SO: WATER-AIR-SOIL-POLLUT. 1990. vol. 52, no. 1-2, pp. 79-96
LA: English
ER: F (Freshwater)
AB: Using lake and stream data collected during the National Surface Water Survey (NSWS), and corrected for regional wet deposition and local cultural contamination, the role of weathering in supplying base cations C sub(B), silica, and alkalinity is evaluated for the southern Blue Ridge (SBR) and southern Piedmont (SPM) Provinces of the United States. Silicate weathering can account for virtually all of the non-cultural (Na+K) leaving the catchments, consistent with the weathering of feldspars to kaolinite, and in some dilute montane catchments, gibbsite. The net export of divalent C sub(B) (Ca+Mg) represents 62 to 66% (median values) of total C sub(B) export for the regional NSWS index sample populations; the alkalis account for the remainder. The median percentage (Ca+Mg) is significantly lower (53%) for SBR special sites, consistent with their unusual vulnerability to acid deposition. Exchange-leaching currently accounts for < 17% of the divalent C sub(B) mobilized in these SBR and SPM catchments, possibly because of the high regional retention rates for both nitrate and sulfate.
AN: 2366986

                                                                   1274 of 1521  
TI: Relationship of reservoir biogeochemical processes to the structural integrity of the world's first totally roller compacted concrete dam.
AU: Larson,-D.W.
AF: Hydraul. and Hydrol., Water Qual., U.S. Army Corps Eng., Portland Dist., P.O. Box 2946, Portland, OR 97208, USA
CO: Int. Conf. on Reservoir Limnology and Water Quality, Ceske Budejovice (Czechoslovakia), 15-20 Jun 1987
SO: PROCEEDINGS-OF-THE-INTERNATIONAL-CONFERENCE-ON-RESERVOIR-LIMNOLOGY-AND-WATER-QUALITY.-3.-KEY-FACTORS-OF-RESERVOIR-LIMNOLOGY,-EUTROPHICATION,-WATER-QUALITY-AND-ITS-PREDICTION. Lind,-O.T.;Sladecek,-V.;Straskrabova,-V.-eds. 1990. no. 33 pp. 949-964
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 33
LA: English
ER: F (Freshwater)
AB: Willow Creek Dam is a U.S. Army Corps of Engineers flood-control project located on a tributary of the Columbia River (Willow Creek) in north-central Oregon, U.S.A. Willow Creek Reservoir is extremely eutrophic and is well stratified thermally during summer. By August, the reservoir's hypolimnion is anoxic and contains high concentrations of hydrogen sulfide (up to 11 mg/l) and other chemically reduced substances. Apparent defects in the dam's concrete matrix have provided avenues for substantial leakage of hypolimnetic waters. Seepage entering the dam's tunnels and gallery is highly enriched with hydrogen sulfide and dissolved lime. There is concern that oxidation of hydrogen sulfide by chemosynthetic bacteria, producing sulfuric acid, is corroding the dam's concrete.
AN: 2366143

                                                                   1275 of 1521  
TI: Radiocarbon evidence of fossil-carbon cycling in sediments of a nearshore hydrocarbon seep.
AU: Bauer,-J.E.; Spies,-R.B.; Vogel,-J.S.; Nelson,-D.E.; Southon,-J.R.
AF: Mar. Res. Div., Scripps Inst. Oceanogr., Univ. California at San Diego, La Jolla, CA 92093, USA
SO: NATURE. 1990. vol. 348, no. 6298, pp. 230-232
LA: English
ER: M (Marine)
AB: Widespread seepage of petroleum and natural gas in the southern California continental borderland provides an opportunity to study the long-term fate and biogeochemical effects of hydrocarbons in nearshore sedimentary environments. The hydrocarbons that enrich seep sediments have been hypothesized to serve as a carbon and energy source for sediment metabolism and infaunal populations. Here we present  super(14)C natural abundances in sediment total organic carbon (TOC), pore-water dissolved inorganic carbon (DIC) and infauna from in and around a hydrocarbon seep off southern California which were measured to help test this hypothesis. Concentrations of  super(14)C in each pool reflect the admixture of fossil ( super(14)C-depleted) seep-derived carbon with carbon from the euphotic zone. The  super(14)C depletion in TOC and DIC increased with proximity to the seepage zone and with sediment depth;  super(14)C abundances differed between meiofauna and macrofauna, suggesting that the two groups incorporate fossil carbon in different ways. The results indicate that fossil carbon can indeed comprise a major component of these carbon pools in nearshore seep sediments.
AN: 2363484

                                                                   1276 of 1521  
TI: Global change expedition: Nutrient, chlorophyll-a and primary productivity data, NOAA ship MT. Mitchell , 14 July-6 September 1988.
AU: Frazel,-D.W.; Berberian,-G.A.; Hitchcock,-G.L.
CA: National Oceanic and Atmospheric Adm., Miami, FL (USA). Atlantic Oceanographic and Meteorological Labs.
SO: NOAA-DATA-REP. 1989. 66 pp
NT: NTIS Order No.: PB90-220336/GAR.
RN: NOAA-DR-ERL-AOML-15 (NOAADRERLAOML15)
LA: English
AB: During the period of 14 July-6 September 1988, a multifaceted oceanographic research cruise called the Global Change Expedition was made on the NOAA Ship MT. Mitchell in the North Atlantic Ocean. The objective of the cruise was to study the atmospheric and oceanic processes affecting the biogeochemical cycles of carbon, nitrogen, sulfur, and trace metals. Emphasis was made on compounds of these elements that would influence the radiation balance of the earth and hence, of global climate. Measurements from hydrocasts for nutrients, phytoplankton biomass, and productivity were made on a daily basis during the period. The report represents the biological and chemical (nutrient) data from the cruise. (Prepared in cooperation with Nova Univ. Oceanographic Center, Dania, FL (USA).)
AN: 2362437

                                                                   1277 of 1521  
TI: Distribution of glycosylglycerols and oligosaccharides in the marine environment and their ecological significance in the deep sea.
AU: Sakugawa,-H.; Handa,-N.; Yagi,-K.
AF: Water Res. Inst., Nagoya Univ., Chikusa-ku, Nagoya 464, Japan
SO: MAR.-BIOL. 1990. vol. 106, no. 2, pp. 309-313
NT: Bibliogr.: 36 ref.
LA: English
ER: M (Marine)
AB: Determination of low molecular weight carbohydrates in marine environments indicated that 1-O- beta -D-galactosylglycerol, 6-O- alpha -D-galactosyl-1-O- beta -D-galactosylglycerol, sucrose, laminaribiose and laminaritriose are widely distributed in seawaters, suspended and sinking particles, and sediments in coastal as well as in deep-sea waters (e.g. Mikawa Bay and Sagami Bay, Kumano Nada (offshore Japan), and northwest North Pacific Ocean, Bering Sea and Antarctic Ocean: collections during 1978-1984). Identification of these glycosylglycerols and oligosaccharides in algal cells such as a flagellate (Olisthodisus luteus ), blue-green algae (e.g. Trichodesmium  sp.) and a diatom (Reptocylindrus denicus ) strongly suggests that these sugars are photosynthetically produced by algae in the euphotic zone and are then rapidly transported to the deep sea as sinking particles which can be collected by sediment-trap experiments.
AN: 2362355

                                                                   1278 of 1521  
TI: Hydrothermal and microbial processes at Loihi Seamount, a mid-plate hot-spot volcano.
AU: Karl,-D.M.; Brittain,-A.M.; Tilbrook,-B.D.
AF: Dep. Oceanogr., Univ. Hawaii at Manoa, Honolulu, HI 96822, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 11A, pp. 1655-1673
LA: English
ER: M (Marine)
AB: Active hydrothermal vents have been discovered at the summit of Loihi Seamount, Hawaii, in an area referred to as Pele's Vents. The active vent field is characterized by iron-rich nontronite deposits, warm (30 degree C) hydrothermal fluids, extensive bacterial mats and by the conspicuous absence of large benthic animals. Chemical analyses of collected water samples has revealed the presence of elevated concentrations of Si, NH super(+)@)d4, PO sub(4)@)u- super(3), dissolved inorganic carbon (DIC), methane (CH sub(4)) and bacterial cells in the discharged vent fluids, relative to ambient bottom seawater. Bacterial mats collected from the vent field are comprised of long filaments coated with Fe precipitates. It is hypothesized that these tubular structures are formed by the growth and metabolism of Fe-oxidizing bacteria.
AN: 2358170

                                                                   1279 of 1521  
TI: The wind-driven "biological pump" and carbon removal in the ocean.
OT: Die Wind-getriebene "biologische Pumpe" und der Kohlenstoffentzug im Ozean
AU: Haake,-B.; Ittekkot,-V.
AF: Geol. Palaeontol. Inst. und Mus., Univ. Hamburg, D-2000 Hamburg, FRG
SO: NATURWISSENSCHAFTEN. 1990. vol. 77, no. 2, pp. 75-79
LA: German
ER: M (Marine)
AB: Fixation of carbon dioxide into organic tissues in the ocean and its subsequent sinking act as a "biological pump" removing CO sub(2) from the atmosphere and surface waters to the deep sea. Most of this sinking occurs in large, biologically formed aggregates made up of organic matter, organism frustules and mineral matter. Strong winds bring nutrient-rich subsurface water to the euphotic zone and increase biological productivity, i.e., CO sub(2) fixation. More importantly, dust particles introduced simultaneously to the sea surface become incorporated into large aggregates thereby increasing densities of settling particles and, as a consequence, effecting the rapid removal of newly fixed organic matter to the deep ocean. These recent findings have important implications for the carbon cycling in the sea.
AN: 2356651

                                                                   1280 of 1521  
TI: Natural abundance of  super(15)N in particulate nitrogen and zooplankton in the Chesapeake Bay.
AU: Montoya,-J.P.; Horrigan,-S.G.; McCarthy,-J.J.
AF: Mus. Comp. Zool., Harvard Univ., Cambridge, MA 12138, USA
SO: MAR.-ECOL.-PROG.-SER.. 1990. vol. 65, no. 1, pp. 35-61
NT: Bibliogr.: 36 ref.
LA: English
ER: M (Marine)
AB: Samples of dissolved inorganic nitrogen (DIN), particulate nitrogen (PN), and several species of zooplankton were collected at a series of stations in the main channel of the Chesapeake Bay, USA, during cruises in spring and fall 1984. The overall gradient of DIN concentrations along the axis of the Bay appears to be less important than local processes in determining the distribution of  super(15)N in PN. The  delta  super(15)N of the zooplankton species sampled generally increased with trophic level. The  delta  super(15)N of the copepod Acartia tonsa  was higher than that of PN by 4.2  plus or minus  2.3 ppt (x@u-  plus or minus  SD) in spring and 3.3.  plus or minus  1.0 ppt (x@u-  plus or minus  SD) in fall. Similarly,  delta  super(15)N of the ctenophore Mnemiopsis leidyi  was higher than that of A. tonsa  by 2.0  plus or minus  2.6 ppt (x@u-  plus or minus  SD) in spring and 3.3  plus or minus  1.0 ppt (x@u-  plus or minus  SD) in fall. A reversal of the usual relationship between A. tonsa  and M. leidyi  occurred near the southern end of the Bay during spring, where  delta  super(15)N of the copepod was greater than that of the ctenophore by as much as 4.9 ppt.
AN: 2354709

                                                                   1281 of 1521  
TI: Chromium biogeochemical cycle in Abu Kir Bay, East of Alexandria, Egypt.
AU: Aboul-Dahab,-O.
AF: Oceanogr. Dep., Fac. Sci., Univ. Alexandria, Alexandria, Egypt
SO: ESTUAR.-COAST.-SHELF-SCI. 1989. vol. 29, no. 4, pp. 327-340
LA: English
ER: M (Marine); B (Brackish)
AB: Abu Kir Bay, east of Alexandria, is affected by two main point sources of pollution, namely Tabia Pumping Station and Lake Edku Outlet. Chromium was measured in the Bay effluents, sea water, marine organisms of different trophic levels, and sediments. The surface distribution of Cr in the coastal waters showed the impact of Tabia Pumping Station on the Bay. Algae and crabs play a critical role in the biological transport of Cr and can be considered the best accumulators of the element.
AN: 2354691

                                                                   1282 of 1521  
TI: NFLUX: A test of vertical nitrogen flux by diel migrant biota.
AU: Longhurst,-A.R.; Bedo,-A.; Harrison,-W.G.; Head,-E.J.H.; Horne,-E.P.; Irwin,-B.; Morales,-C.
AF: Biol. Oceanogr. Div., Bedford Inst. Oceanogr., Dep. Fish. and Oceans, P.O. Box 1006, Dartmouth, N.S. B2Y 4A2, Canada
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 11A, pp. 1705-1719
LA: English
ER: M (Marine)
AB: At a station (NFLUX), occupied for 10 days in the northern Sargasso Sea, we assembled data to test the hypothesis that diel migrant biota in the open ocean induce a downward flux of dissolved inorganic nitrogen that is significant in relation to the passive flux under gravity of particulate organic nitrogen at the base of the photic zone. We found that NH super(+)@)d4 excretion rates by day at depths below the photic zone were approximately 8% of particulate nitrogen flux obtained by a sediment trap array at the same depth. This figure is in the lower part of the range of values calculated previously for 10 published station data sets; we attribute this to the quite high rate of passive flux relative to primary production at the NFLUX station.
AN: 2354663

                                                                   1283 of 1521  
TI: Mass balance of biogeochemically active materials (C, N, P,) in a hypersaline gulf.
AU: Smith,-S.V.; Veeh,-H.H.
AF: Hawaii Inst. Mar. Biol., Univ. Hawaii at Manoa, 1000 Pope Rd., Honolulu, HI 96822, USA
SO: ESTUAR.-COAST.-SHELF-SCI. 1989. vol. 29, no. 3, pp. 195-215
LA: English
ER: M (Marine); B (Brackish)
AB: We have examined the mass balance of water, salt, C, N, and P in Spencer Gulf, a large inverse estuary in South Australia. The fluxes of C, N, and P are biologically mediated, and we look for a plausible interaction among these fluxes. The CO sub(2) system appears remarkably "balanced" by its fluxes - to relatively constant pH, PCO sub(2), and calcite saturation state. We conclude that supply of PO sub(4) super(3-) largely controls characteristics of C and N flux. The controls postulated for P include CaCO sub(3) precipitation, CO sub(2) gas flux, organic C production, and N fixation.
AN: 2353244

                                                                   1284 of 1521  
TI: Bacterial cycling of minerals that affect plant growth in waterlogged soils: A review.
AU: Laanbroek,-H.J.
AF: Inst. Ecol. Res., R. Neth. Acad. Sci., P.O. Box 40, 6666 ZG Heteren, Netherlands
CO: Symp. in Adaptation of Plants to Flooding, Wageningen (Netherlands), Dec 1988
SO: ADAPTATION-OF-PLANTS-TO-FLOODING. Blom,-C.W.P.M.-ed. 1990. vol. 38, no. 1 pp. 109-125
ST: AQUAT.-BOT. vol. 38, no. 1
NT: Special issue.
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: Plant growth in waterlogged soils may be greatly affected by reduced minerals such as ammonium, manganous and ferrous ions, and sulphide. A more detailed description is given of the microbial and chemical processes that lead to reduced minerals, as well as of the micro-organisms involved. Reduction processes do not occur simultaneously, but consecutively according to a fixed sequence: oxygen, nitrate, manganese (IV) oxide, ferric oxide, sulphate and carbon dioxide. Special attention is paid to the microbial mechanisms of mutual exclusion of reduction processes. Re-oxidation of reduced minerals occurs at the oxic-anoxic interfaces in the flooded soil, i.e. at the oxidized upper layers of the soil and in the oxidized rhizosphere of waterlogged plants with aerenchyma. The micro-organisms involved in the oxidation processes with oxygen are mentioned in relation to their ecological niches.
AN: 2352450

                                                                   1285 of 1521  
TI: The evolution of saline lake waters: Gradual and rapid biogeochemical pathways in the Basotu Lake District, Tanzania.
AU: Kilham,-P.; Cloke,-P.L.
AF: Dep. Biol., Univ. Michigan, Ann Arbor, MI 48109-1048, USA
CO: 4. Int. Symp. on Athalassic (Inland) Saline Lakes, Banyoles (Spain), 2-8 May 1988
SO: SALINE-LAKES. Comin,-F.A.;Northcote,-T.G.-eds. 1990. vol. 197 pp. 35-50
ST: HYDROBIOLOGIA. vol. 197
LA: English
ER: B (Brackish)
AB: The biogeochemical evolution of solutes markedly alters the chemistry in the closed-basin maar lakes that comprise the Basotu Lake District (Tanzania, East Africa). Examination of 11 (out of 13) lakes in the Basotu Lake District identified two distinct evolutionary pathways: a gradual path and a rapid path. During the course of biogeochemical evolution these waters follow either the gradual path alone or a combination of the gradual and rapid paths. Solute evolution along the gradual path is determined by all the biogeochemical processes that for these waters appear to be tightly coupled to evaporative concentration (e.g. mineral precipitation, sorption and ion exchange, CO sub(2) degassing, and sulfate reduction).
AN: 2351357

                                                                   1286 of 1521  
TI: Role of zooplankton in the nitrogen cycle off the west coast of the South Island, New Zealand, winter 1987.
AU: James,-M.R.
AF: Taupo Res. Lab., Div. Water Sci., Dep. Sci. and Ind. Res., P.O. Box 415, Taupo, New Zealand
SO: N.Z.-J.-MAR.-FRESHWAT.-RES. 1989. vol. 23, no. 4, pp. 507-518
LA: English
ER: M (Marine)
AB: Zooplankton abundance, feeding, and ammonia regeneration rates were measured along three transects off the west coast of the South Island, New Zealand, in winter (July) 1987. Crustacean nauplii and copepodites dominated the 55-200  mu m fraction of the microzooplankton. Tintinnid population dynamics were related to the degree of freshwater influence. Tintinnid species with silica-encrusted bowls were common close inshore and species with no encrustations were common offshore. The most abundant macrozooplankton were the small copepod Acartia ensifera, Paracalanus indicus, Oithona similis, Centropages aucklandicus , and Clausocalanus jobei. A. ensifera  dominated at the inshore stations, whereas the outer stations had a mixture of neritic/outer shelf and oceanic species.
AN: 2350574

                                                                   1287 of 1521  
TI: Nitrogen assimilation by three size fractions of the winter phytoplankton off Westland, New Zealand.
AU: Chang,-F.H.; Vincent,-W.F.; Woods,-P.H.
AF: New Zealand Oceanogr. Inst., Div. Water Sci., Dep. Sci. and Ind. Res., Priv. Bag, Kilbirnie, Wellington, New Zealand
SO: N.Z.-J.-MAR.-FRESHWAT.-RES. 1989. vol. 23, no. 4, pp. 491-505
LA: English
ER: M (Marine)
AB: The assimilation of ammonium, nitrate, and urea by the phytoplankton community off the Westland coast was measured in a detailed series of  super(15)N-assays in mid winter, 1987. The average nitrogen (N) uptake rates for the three substrates for three size classes of phytoplankton (< 2, < 20, < 200,  mu m) followed the distribution of biomass as measured by chlorophyll a, with higher values inshore. Nitrate accounted for 56% of the total N utilised by the entire community (< 200  mu m), whereas ammonium and urea made up c. 19 and 25%, respectively. These data imply that new N provided a greater nutritional source than regenerated N for the growth of the dominant size components (< 2, 2-20  mu m) of the midwinter phytoplankton community.
AN: 2350559

                                                                   1288 of 1521  
TI: Distribution of arsenite and total dissolved arsenic in major French estuaries: Dependence on biogeochemical processes and anthropogenic inputs.
AU: Seyler,-P.; Martin,-J.M.
AF: Inst. Biogeochim. Mar., UA 386 CNRS, Ec. Norm. Super. 1, Rue Maurice Arnoux, F-92120 Montrouge, France
SO: MAR.-CHEM. 1990. vol. 29, no. 2-3, pp. 277-294
LA: English
ER: B (Brackish)
AB: The distribution of arsenite (As (III)), total dissolved arsenic and particulate arsenic was studied in major French rivers/estuaries which are representative of polluted, unpolluted, macrotidal and stratified systems. In the Rhone Estuary (with flushing time of the order of 1 day) the maximum of dissolved arsenic (25-50 nM) occurring in the low-salinity zone is related to the variability of the river input. In the Gironde Estuary (flushing time 20-86 days) arsenite and total dissolved As concentrations vs. chlorinity plots show a maximum (45 nm for dissolved arsenic) located in the low-salinity zone within the turbidity maximum. In the Loire fluvio-estuarine system the maxima of arsenite (15 nM) and total dissolved arsenic (25 nM) are attributed to the anthropogenic inputs from land-based industries, and especially from the coal-power plant. The dissolved arsenic discharge has been estimated at 40 tons/yr.
AN: 2336702

                                                                   1289 of 1521  
TI: Downward flux of particulate fatty acids in the Central Arabian Sea.
AU: Reemtsma,-T.; Haake,-B.; Ittekkot,-V.; Nair,-R.R.; Brockmann,-U.H.
AF: Geol.-Palaeontol. Inst. und Mus., Univ. Hamburg, Bundesstr. 55, 2000 Hamburg 13, FRG
SO: MAR.-CHEM. 1990. vol. 29, no. 2-3, pp. 183-202
LA: English
ER: M (Marine)
AB: Particulate matter collected at 732 and 2914 m during a time-series sediment trap experiment (sampling interval 13 days) in the Central Arabian Sea (14 degree 29'N, 64 degree 46'E; water depth 4016 m) was analysed for its fatty acid and organic carbon contents. The sampling period covered the summer monsoon of 1986. Contents of organic carbon and fatty acid decrease with increasing particle fluxes. At 732 m fatty acids account for 0.6-4% of organic carbon. Particulate organic matter collected during high productivity and high-flux periods exhibits signs of less intense degradation within the surface layers. Selective degradation of fatty acids diminishes their contribution to organic carbon in the deeper trap (0.3-0.7%). Despite this, the seasonality in fatty acid flux is maintained down to the deep ocean.
AN: 2336638

                                                                   1290 of 1521  
TI: Element budgets of two contrasting catchments in the Black Forest (Federal Republic of Germany).
AU: Feger,-K.H.; Brahmer,-G.; Zoettl,-H.W.
AF: Inst. Soil Sci. and Forest Nutr., Albert-Ludwig-Univ., D-7800 Freiburg im Breisgau, FRG
SO: J.-HYDROL.-AMST.. 1990. vol. 116, no. 1-4, pp. 85-99
LA: English
AB: Rainfall and throughfall inputs of all major cations and anions, via open-field bulk precipitation and canopy throughfall, are compared with streamwater outputs in two forested catchments at higher altitudes of the Black Forest. The sites differ considerably in terms of bedrock geology, soil type soilwater characteristics, topography, and forest management history. Deposition at both sites is almost equal and, in contrast to other forest areas in Central Europe, of a low-to-moderate level. Dry deposition does not seem to play an important role. Distinct differences in the elemental output emerge owing to the differing site conditions. At Villingen, deposited nitrogen is almost totally retained, whereas at Schluchsee, nitrogen output and input are of the same order of magnitude. This is consistent with the different nitrogen nutrition level of the stands, microbial turnover in the soil, and former management practices (change of tree species, excessive nutrient export). Sulphur is not retained in either of the catchments.
AN: 2334089

                                                                   1291 of 1521  
TI: Longitudinal patterns of concentration-discharge relationships in stream water draining the Hubbard Brook Experimental Forest, New Hampshire.
AU: Lawrence,-G.B.; Driscoll,-C.T.
AF: Dep. Plant and Soil Sci., Deering Hall, Univ. Maine, Orono, ME 04469, USA
SO: J.-HYDROL.-AMST.. 1990. vol. 116, no. 1-4, pp. 147-165
LA: English
ER: F (Freshwater)
AB: Longitudinal variations of concentration-discharge relationships and chemical fluxes were evaluated in two headwater streams at the Hubbard Brook Experimental Forest, New Hampshire. At high elevations changes in subsurface flow paths explained variations in H super(+), inorganic Al and Si concentrations, whereas variations of DOC concentration were inconsistent with this mechanism. Flow responses of middle and low elevation subcatchments were influenced by variable contributions of hydrologic source areas and the elevational concentration gradient which exists in these catchments, but in most cases were not consistent with responses predicted by changes in flow paths. Spatial patterns of chemical fluxes indicate that catchment neutralization processes increased in effectiveness in the downslope direction. However, this pattern can be interrupted by secondary tributaries, which originate in variable source areas that contribute acidic surface runoff during high flow conditions.
AN: 2334067

                                                                   1292 of 1521  
TI: Hydrogeochemical variations in Hafren forest stream waters, Mid-Wales.
AU: Neal,-C.; Smith,-C.J.; Walls,-J.; Billingham,-P.; Hill,-S.; Neal,-M.
AF: Inst. Hydrol., Maclean Build., Crowmarsh Gifford, Wallingford OX10 8BB, UK
SO: J.-HYDROL.-AMST.. 1990. vol. 116, no. 1-4, pp. 185-200
LA: English
ER: F (Freshwater)
AB: Results are presented to assess the effects of conifer planting/harvesting and acidic oxide deposition on streamwater quality in a 25 to 45-year-old sitka spruce plantation on acid moorland. Hafren forest streamwater chemistry varies for different components: nitrate, bromide, total iodine and total organic carbon show seasonal oscillations varying in phase and amplitude; aluminium and hydrogen ion concentrations vary as a function of flow; manganese and cobalt remain approximately constant except under very dry conditions when concentrations reduce by up to 10 fold. No direct link exists between rain and streamwater chemistry: streamwater chemistry variations are determined primarily by hydrological and chemical reactions in the surface organic-rich soils and the underlying inorganic soils/bedrock. Reactions in the organic-rich horizons involve the generation of acidic conditions and the mobilization/transport of transition metals that can be easily hydrolysed. Biologically mediated breakdown processes determine, in part, the hydrochemical behaviour of dissolved organic carbon, the nutrients, bromine and iodine.
AN: 2334043

                                                                   1293 of 1521  
TI: Biogeochemical cycling of manganese at hydrothermal vents.
AU: Tebo,-B.M.
CA: Scripps Inst. of Oceanography, La Jolla, CA (USA). Marine Biological Research Div.
SO: 1990. 4 pp
NT: NTIS Order No.: AD-A219 360/5/GAR. Contract N00014-87-K-0532.
LA: English
ER: M (Marine)
AB: The interactions between bacteria and metals in the ocean are profoundly important both in environments with high levels of metals, such as hydrothermal vents. Metals affect primary productivity by both metal limitation of phytoplankton growth and by serving as a potential energy source for bacterial (autotrophic) growth. In addition, the highly charged surfaces of metal oxide particles, which, to a large extent, are microbially produced, govern much trace metal and organic geochemistry. The role these oxides surfaces play is evident both in hydrothermal vent plumes (which, because they are dispersed hundreds of kilometers away from venting sources, have a profound influence on the chemistry and ecology of the deep sea) as well as in the photic zone.
AN: 2333795

                                                                   1294 of 1521  
TI: Precipitation, throughfall, soil solution and stream-water chemistry in a holm-oak (Quercus ilex ) forest.
AU: Roda,-F.; Avila,-A.; Bonilla,-D.
AF: Cent. Rec. Ecol. i Apl. For., Univ. Auton. Barcelona, 08193 Bellaterra, Spain
SO: J.-HYDROL.-AMST.. 1990. vol. 116, no. 1-4, pp. 167-183
LA: English
ER: F (Freshwater)
AB: Bulk precipitation, throughfall, soil solution at 20 and 40 cm depths, and stream water were monitored for 2-4 years in a holm-oak forest on schists in the Montseny Mountains (NE Spain). Bulk precipitation was mildly acidic, with Ca super(2+) and SO sub(4)@) super(2)-a)s dominant ions. Canopy interactions produced a throughfall less acidic than bulk precipitation and enriched in all other ions. Large amounts of K super(+) were leached from the canopy. Magnesium in net throughfall behaved similarly to K super(+), and it is concluded that leaching makes a major contribution to Mg super(2+) enrichment beneath the canopy. Judging from the moderate increase of Na super(+) and Ca super(2+) in throughfall, dry deposition rates for both marine and continental aerosols were low in the studied stand, probably because of its sheltered topographic position within a well-vegetated massif, coupled with moderate tree height and low canopy roughness. It is concluded that: (1) this forest does not currently receive acidic atmospheric deposition; (2) the neutralization capacity of the soil-bedrock system is quite high; (3) biotic regulation and silicate weathering are the major processes shaping the solution biogeochemistry in this Mediterranean forest ecosystem.
AN: 2333631

                                                                   1295 of 1521  
TI: Effects of vegetation type on the biogeochemistry of small catchments (Mont Lozere, France).
AU: Lelong,-F.; Dupraz,-C.; Durand,-P.; Didon-Lescot,-J.F.
AF: Lab. Hydrogeol. et UA 724, CNRS, Univ. Orleans, B.P. 6759, 45067 Orleans, Cedex 2, France
SO: J.-HYDROL.-AMST.. 1990. vol. 116, no. 1-4, pp. 125-145
LA: English
ER: F (Freshwater)
AB: Input-output budgets are presented for 3 granitic catchments, with contrasting vegetation types (Spruce, Beech and grassland), for the Mont Lozere region of France. Budget results are compared with information for analogous catchments with varying atmospheric pollution loading. Comparisons show relatively small losses of cations and marked sulphate retention in the soils (particularly for the beech and grassland sites) of the Mont Lozere catchments. Retention of sulphate may be underestimated, particularly for the spruce site, owing to occult and dry deposition inputs which have not been measured. Specific effects of the vegetation type upon the soil dynamics and the biological functioning of the ecosystem are described. Losses of the base cations are least significant for the beech forest, and this is linked to low bicarbonate production coupled with high sulphate retention in the soil.
AN: 2333607

                                                                   1296 of 1521  
TI: Hydrological and hydrochemical fluxes through vegetation and soil in the Allt a'Mharcaidh, western Cairngorms, Scotland: Their effect on streamwater quality.
AU: Ferrier,-R.C.; Walker,-T.A.B.; Harriman,-R.; Miller,-J.D.; Anderson,-H.A.
AF: Macaulay Land Use Res. Inst., Craigiebuckler AB9 2QJ, UK
SO: J.-HYDROL.-AMST.. 1990. vol. 116, no. 1-4, pp. 251-266
LA: English
ER: F (Freshwater)
AB: A detailed investigation of the hydrochemical alteration of input water by vegetation and soils was undertaken in an upland catchment in the Cairngorm Mountain region of Scotland. The composition of catchment outflow water reflects the hydrological routing of water through different soil horizons and the importance of long residence time water. There is uptake of nitrogen and neutralization of incoming anthropogenic acidity by the vegetation, and sulphate adsorption in the mineral soils. Streamwater quality is dominated by the contribution of long residence time water, especially during base flow. Sulphate retention and cation release are the major neutralization mechanisms buffering outflow chemistry at this site.
AN: 2333567

                                                                   1297 of 1521  
TI: A thiosulfate shunt in the sulfur cycle of marine sediments.
AU: Joergensen,-B.B.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, 8000 Aarhus C, Denmark
SO: SCIENCE-WASH.. 1990. vol. 249, no. 4965, pp. 152-154
LA: English
ER: M (Marine)
AB: The oxidation of sulfide, generated by bacterial sulfate reduction, is a key process in the biogeochemistry of marine sediments, yet the pathways and oxidants are poorly known. By the use of  super(35)S-tracer studies of the S cycle in marine and freshwater sediments, a novel shunt function of thiosulfate (S sub(2)O sub(3) super(2-)) was identified. The S sub(2)O sub(3) super(2-) constituted 68 to 78 percent of the immediate HS super(-)-oxidation products and was concurrently (i) reduced back to HS super(-), (ii) oxidized to SO sub(4) super(2-), and (iii) disproportionated to HS super(-) + SO sub(4) super(2-). The small thiosulfate pool is thus involved in a dynamic HS super(-)-S sub(2)O sub(3) super(2-) cycle in anoxic sediments. The disproportionation of thiosulfate may help account for the large difference in isotopic composition ( super(34)S/ super(32)S) of sulfate and sulfides in sediments and sedimentary rocks.
AN: 2331411

                                                                   1298 of 1521  
TI: Two-isotope characterization of N sub(2)O in the Pacific Ocean and constraints on its origin in deep water.
AU: Kim,-Kyung-Ryul; Craig,-H.
AF: Dep. Oceanogr., Seoul Natl. Univ., Seoul 151-742, Rep. Korea
SO: NATURE. 1990. vol. 347, no. 6288, pp. 58-61
LA: English
ER: M (Marine)
AB: Three decades after the first study of nitrous oxide (N sub(2)O) in the ocean, the marine geochemistry of this compound is of exceptional interest for two reasons: first, the need to understand the role of N sub(2)O in both nitrification and denitrification in the sea, and second, the importance of N sub(2)O in the stratospheric ozone cycle and as a greenhouse trace gas that, molecule for molecule, is 200 times more effective than carbon dioxide. Related questions concern the role of the ocean as a source or sink of tropospheric N sub(2)O and the processes responsible for its production and consumption in the sea. Our approach to these problems is one that has been successful in studies of H sub(2)O geochemistry and sources of atmospheric CO (ref. 9): the simultaneous study of two isotopic components of a molecule, here the  super(15)N/ super(14)N and  super(18)O/ super(16)O ratios.
AN: 2324362

                                                                   1299 of 1521  
TI: Role of sub-micrometre particles in the ocean.
AU: Isao,-K.; Hara,-S.; Terauchi,-K.; Kogure,-K.
AF: Ocean Res. Inst., Univ. Tokyo, Nakano, Tokyo 164, Japan
SO: NATURE. 1990. vol. 345, no. 6272, pp. 242-244
LA: English
ER: M (Marine)
AB: Particulate matter plays an important part in biogeochemical cycles in the ocean; as particles settle out of the water column, they carry with them carbon and other adsorbed chemicals. Here the authors present results from epifluorescence microscopy and from particle counting which have allowed us to determine the vertical distribution of submicrometre particles (size range 0.38-1  mu m). We find that > 95% of these particles are non-living and occur in the upper layers of the ocean (50 m) in concentrations of the order of 10 million per millilitre. Many of the non-living particles seem to be fragile and flexible, and seem to have a high water content and to be composed largely of organic material. The size distribution of these submicrometre particles leads the authors to conclude that a significant portion (at least 10%) of "dissolved" organic material may in fact be in the form of these small particles, as suggested by Sharp.
AN: 2313377

                                                                   1300 of 1521  
TI: Limnology of four groundwater-fed saline lakes in south-western Australia.
AU: Burke,-C.M.; Knott,-B.
AF: Dep. Zool., Univ. Western Australia, Nedlands, W.A. 6009, Australia
SO: AUST.-J.-MAR.-FRESHWAT.-RES. 1989. vol. 40, no. 1, pp. 55-68
LA: English
ER: B (Brackish)
AB: Salinity, temperature, dissolved oxygen (DO), pH and total alkalinity (TA) were measured in four saline lakes of Yalgorup National Park, Western Australia, primarily over an 18-month period, July 1985 to January 1987, but also during 1987 and in 1988. These are shallow (<3 m) ground-water sinks with no surface drainage. Rainfall and hence ground-water inflow to the lakes was highly seasonal and occurred mainly between May and October. Lakes Hayward, North Newnham and South Newnham were consistently hypersaline (e.g. Hayward 61-214 g/L) and Hayward and North Newnham were stratified from autumn to early summer. The bottom layer of water in Hayward was usually supersaturated (to 430%) with respect to DO, because of the photosynthetic activity of the benthic microbial communities (BMC). During spring, extensive growth of the charophyte Lamprothamnium papulosum  across the sediments in Lake Pollard increased DO (from c. 140% saturation) and pH (from c. 8 multiplied by 5 to c. 10), but lowered specific TA (from 0 multiplied by 26 to 0 multiplied by 07 meq/L per unit salinity); later removal of the L. papulosum  by swans reduced DO to 50% saturation and pH to 7 multiplied by 5, and increased specific TA to 0 multiplied by 15 meq/L per unit salinity.
AN: 2313202

                                                                   1301 of 1521  
TI: Transfer and biogeochemistry of organic matter at the water-sediment interface in a north-western Mediterranean canyon.
AU: Buscail,-R.; Gadel,-F.
AF: Lab. Sedimentol. Geochim. Mar., UA 715 CNRS, Univ. Perpignan, 66025 Perpignan, France
CO: 8. Int. Symp. on Environmental Biogeochemistry, Nancy (France), 14 Sep 1987
SO: RECL.-TRAV.-LAB.-SEDIMENTOL.-GEOCHIM.-MAR.-UNIV.-PERPIGNAN. 1987. vol. 4, 1 p
NT: Summary only.
LA: English
ER: M (Marine)
AB: With reference to the biogeochemical cycles of organic carbon in the marine environment, we study the transfer of organic matter and its deposits from the coastal zone near a river mouth to the base of the northwestern margin of the Gulf of Lion. Five bathymorphologic sites were sampled in the Locaze-Luthiers canyon with a Reineck box-corer. The importance of continental or marine sources is stressed by physico-chemical characteristics of suspended matter collected near the bottom by sediment traps.
AN: 2309157

                                                                   1302 of 1521  
TI: Role of heterotrophic bacteria in regulating ammonium utilization, new production and CO sub(2) cycling.
AU: Keil,-R.G.; Kirchman,-D.L.
AF: Coll. Mar. Stud., Univ. Delaware, Lewes, DE 19958, USA
CA: Marine Technology Soc., Washington, DC (USA)
IEEE Ocean Engineering Soc., New York, NY (USA)
CO: Oceans '89, Seattle, WA (USA), 18-21 Sep 1989
SO: OCEANS-'-89:-THE-GLOBAL-OCEAN.-VOLUME-1:-FISHERIES,-GLOBAL-OCEAN-STUDIES,-MARINE-POLICY-AND-EDUCATION,-OCEANOGRAPHIC-STUDIES. 1989. p. 292
ST: OCEANS-'-89.
NT: Summary only.
RN: IEEE-89CH2780-5 (IEEE89CH27805)
LA: English
ER: M (Marine)
AB: Ammonium cycling partly determines nitrate utilization by phytoplankton, new production, and indirectly the exchange of CO sub(2) between the atmosphere and the oceans. The role heterotrophic bacteria play in ammonium cycling is unclear. Investigations in the subarctic Pacific and the midcontinental Atlantic shelf indicate that heterotrophic bacteria consume or regenerate ammonium in response to the supply of dissolved free amino acids. Results of whole water incubations with  super(15)NH sub(4) super(+) indicate that bacteria can consume  similar to 30% of the ammonium taken up in subarctic Pacific waters. Additional experiments using  super(15)NH sub(4) super(+) tracers show that amino acid additions (0.3-1.0  mu M) inhibit uptake of ammonium by bacteria. In 0.8  mu m size fractions dominated by heterotrophic bacteria, bacteria regenerated ammonium only when amino acid supply met or exceeded bacterial nitrogen demand. In coastal mid-Atlantic waters, amino acid additions (1.0  mu M) have been shown to inhibit uptake of  super(15)N-nitrate by phytoplankton.
AN: 2308642

                                                                   1303 of 1521  
TI: Erosion and sediment yield research -- some recent perspectives.
AU: Walling,-D.E.
AF: Dep. Geogr., Univ. Exeter, Exeter EX4 4RJ, UK
SO: J.-HYDROL.-AMST.. 1988. vol. 100, no. 1-3, pp. 113-141
LA: English
AB: Recent assessments of both the on-farm and off-farm costs of soils loss and sedimentation have emphasized the relevance of research in the field of erosion and sedimentation and this has been further underscored by an increasing awareness of the importance of sediment-associated transport in the movement of contaminants through terrestrial and aquatic ecosystems. In response to these challenges, research has expanded and several new foci of interest can be identified. This review considers three which are seen to be of particular significance.
AN: 2308465

                                                                   1304 of 1521  
TI: Phosphorus budget in an atoll lagoon.
AU: Charpy,-L.; Charpy-Roubaud,-C.J.
AF: ORSTOM Tahiti, P.O. Box 529, Papeete, French Polynesia
CO: 6. Int. Coral Reef Symp., Townsville, Qld. (Australia), 8-12 Aug 1988
SO: PROCEEDINGS-OF-THE-SIXTH-INTERNATIONAL-CORAL-REEF-SYMPOSIUM,-TOWNSVILLE,-AUSTRALIA,-8th-12th-AUGUST-1988.-VOLUME-2:-CONTRIBUTED-PAPERS-MINI-SYMPOSIUM-1-TO-10-14. Choat,-J.H.;Barnes,-D.;Borowitzka,-M.A.;Coll,-J.C.;Davies,-P.J.;Flood,-P.;Hatcher,-B.G.;et-al.-eds.. 1988. pp. 547-550
LA: English
ER: M (Marine)
AB: The different states of phosphorus (mineral, organic, dissolved and particulate) were studied between 1982 and 1987 in the oceanic and lagoon waters and sediment pore waters of the atoll of Tikehau. Fluxes associated with the different forms of phosphorus were measured or estimated. The percentages of phosphorus forms in the lagoon are 58% for the dissolved organic (DOP), 23% for the phosphates (PO sub(4)) and 18% for the particulate organic (POP). Living POP is composed by 28% of phytoplankton, 20% of heterotrophs < 5  mu m, 26% of heterotrophs 5  mu m-35  mu m and 26% of zooplankton (35  mu m - 2000  mu m). Phosphate flux from sediment give all the phosphorus required by phytobenthic production. Detritus probably come from reef production. POP exportation from the lagoon represents only 2.5% of phytoplankton production.
AN: 2304638

                                                                   1305 of 1521  
TI: Nitrogen fixation by epilithic periphyton in small arctic lakes in response to experimental nitrogen and phosphorus fertilization.
AU: Bergmann,-M.A.; Welch,-H.E.
AF: Dep. Fish. Oceans, 501 University Crescent, Winnipeg, Man. R3T 2N6, Canada
SO: CAN.-J.-FISH.-AQUAT.-SCI. 1990. vol. 47, no. 8, pp. 1545-1550
NT: Incl. bibliogr.: 22 ref.
LA: English
ER: F (Freshwater)
AB: Epilithic periphyton played a moderate role in the nitrogen budget small arctic lakes located at Saqvaqjuac, N.W.T. The acetylene reduction technique used to estimate nitrogen fixation indicated that periphyton in 0-2 m water depth were capable of fixing up to 0.86 mg N m super(-2) h during the period of active nitrogen fixation from July to September 1981. Far Lake was fertilized with phosphorus for 3 yr and had a higher rate of fixation than did a P- and N-fertilized lake or a control lake, in agreement with similar studies on temperate and subarctic lakes. A numerical model based on incoming light was used to predict the amount of nitrogen fixed in each study lake throughout the season.
AN: 2304390

                                                                   1306 of 1521  
TI: Some characteristic features and regularities of sedimentogenesis in the northwestern part of the Black Sea (composition and distribution of suspended matter).
OT: Nekotorye osobennosti i zakonomernosti sedimentogeneza v severo-zapadnoj chasti Chernogo morya (veshchestvennyj sostav i raspredelenie vzvesi)
AU: Khrustalev,-Yu.P.; Chernousov,-S.Ya.; Denisov,-V.I.
AF: Gos. Univ. Rostov, USSR
SO: OKEANOLOGIYA-OCEANOLOGY. 1990. vol. 30, no. 2, pp. 288-294
LA: Russian
ER: M (Marine)
AB: Based on the results of expeditional studies conducted in 1979-1985 regularities of influx, distribution and accumulation of particulate suspended matter are analysed. Major types of suspensions are distinguished and patterns of their distribution by seasons are revealed. Solid river discharge, water dynamics and plankton abundance are identified as decisive factors governing seasonality in the distribution of suspended matter concentrations.
AN: 2303624

                                                                   1307 of 1521  
TI: Detritus in coral reef ecosystems: Fluxes and fates.
AU: Alongi,-D.M.
AF: Australian Inst. Mar. Sci., P.M.B. No. 3, Townsville, M.C., Qld. 4810, Australia
CO: 6. Int. Coral Reef Symp., Townsville (Australia), 8-12 Aug 1988
SO: PROCEEDINGS-OF-THE-SIXTH-INTERNATIONAL-CORAL-REEF-SYMPOSIUM,-TOWNSVILLE,-AUSTRALIA,-8th-12th-AUGUST-1988.-VOLUME-1:-PLENARY-ADDRESSES-AND-STATUS-REVIEWS. Choat,-J.H.;Barnes,-D.;Borowitzka,-M.A.;Coll,-J.C.;Davies,-P.J.;Flood,-P.;Hatcher,-B.G.;Hopley,-D.;et-al.-eds.. 1988. pp. 29-36
NT: Incl. bibliogr.: 74 ref.
LA: English
ER: M (Marine)
AB: Present models of detritus fluxes on coral reefs are too simplistic in ignoring or underestimating the role of microbes, the influence of water-column hydrography on the distribution and abundances of organisms and particulate and dissolved nutrients, and rates of detritus consumption by reef organisms. Biochemical changes in aging reef detritus and the magnitude of biogeochemical cycles on coral reefs are largely unknown, despite their acknowledged importance in detrital recycling in other marine systems. A review of the reef literature indicates that most of the above-cited aspects continue to be ignored. It is plausible that microbes, particularly in subsurface anaerobic sediments, are a sink for carbon in coral reef ecosystems.
AN: 2301962

                                                                   1308 of 1521  
TI: The trophic roles of bacteria in marine ecosystems are complicated by synergistic-consortia and mixotrophic-cometabolism.
AU: McN.-Sieburth,-J.
AF: Grad. Sch. Oceanogr., Univ. Rhode Island, Bay Campus, S. Ferry Rd., Narragansett, RI 02822-1197, USA
CO: 1. Int. Symp. on the Microbial Ecology of the Mediterranean Sea (MEM I), Sorrento (Italy), Jun 1987
SO: ASPECTS-OF-MARINE-MICROBIOLOGY. Jones,-E.B.G.;Miller,-J.D.-eds. 1988. vol. 21, no. 2 pp. 117-128
ST: PROG.-OCEANOGR. vol. 21, no. 2
LA: English
ER: M (Marine)
AB: This paper deals with the following topics. 1. Stable, Stratified Ecosystems: Ideal Habitats for Trophic Studies on Marine Bacteria; 2. Synergistic Consortia; 3. Upper Ocean Processes may be Dependent upon the Consortia in Oxic-Anoxic Microparticulates; 4. Mixotrophic Cometabolism; 5. "Bacterial Growth Rates" and "Trophic Rates", the appropriate use of radioisotopes.
AN: 2301365

                                                                   1309 of 1521  
TI: Mineralization of organic material in coastal eutrophic ecosystems according to available terminal electron acceptors.
AU: Marty,-D.; Bertrand,-J.C.; Caumette,-P.; Bianchi,-A.
AF: Microbiol. Mar., CNRS, ER 223, Campus Luminy, Case 907, 70 Route Leon Lachamp, F-13288 Marseille, Cedex 9, France
CO: 1. Int. Symp. on the Microbial Ecology of the Mediterranean Sea (MEM I), Sorrento (Italy), Jun 1987
SO: ASPECTS-OF-MARINE-MICROBIOLOGY. Jones,-E.B.G.;Miller,-J.D.-eds. 1988. vol. 21, no. 2 pp. 167-176
ST: PROG.-OCEANOGR. vol. 21, no. 2
LA: English
ER: M (Marine)
AB: In aquatic ecosystems, the flux of organic matter to bottom sediments depends on primary productivity at the ocean surface and on water depth. In most coastal and intertidal areas, detrital input to the bottom sediments is appreciable, consequently, the neritic sediments are important sites of mineralization and nutrient regeneration of deposited organic matter. This organic matter can be oxidized via oxidative and/or fermentative processes by transfer of electrons to terminal acceptors. The distribution of sedimentary microbial communities involved in carbon flow depends on the availability of diverse electron acceptors and on the efficiency of the different bacteria employing specific electron acceptors.
AN: 2301151

                                                                   1310 of 1521  
TI: The significance of microalgal blooms for fisheries and for the export of particulate organic carbon in oceans.
AU: Legendre,-L.
AF: Dep. Biol., Univ. Laval, Ste-Foy, Que. G1K 7P4, Canada
SO: J.-PLANKTON-RES. 1990. vol. 12, no. 4, pp. 681-699
LA: English
ER: M (Marine)
AB: Microalgal blooms are rapid increases in biomass, caused by locally enhanced primary production and resulting in abnormally high cell concentrations. Hydrodynamical processes may control blooms through the agency of irradiance and/or nutrients. In the oceans, phytoplankton blooms primarily governed by irradiance include the spring outburst, as well as the ice-edge, under-ice, winter, upwelling and estuarine blooms. Those primarily governed by nutrients comprise the tidal, summer, episodic and exceptional blooms. In addition, there are blooms of ice-microalgae. Blooms reflect low recycling, and a large degree of uncoupling between increased primary production and grazing by zooplankton. As a consequence, they often result in high sedimentation of intact cells and faecal pellets. Microalgal blooms provide unique information on the potential fate (and not on the rate) of primary production in marine ecosystems.
AN: 2296767

                                                                   1311 of 1521  
TI: Assessment of inorganic nitrogen fluxes across the sediment-water interface in a tropical lagoon.
AU: Corredor,-J.E.; Morell,-J.M.
AF: Univ. Puerto Rico, Dep. Mar. Sci., Mayaguez 00709, Puerto Rico
SO: ESTUAR.-COAST.-SHELF-SCI. 1989. vol. 28, no. 6, pp. 339-345
LA: English
ER: M (Marine); B (Brackish)
AB: Fluxes of ammonium and nitrate plus nitrite between the sediment and the water column in a shallow tropical lagoon were computed using experimental incubations and theoretical calculations based on observed gradients. Rates computed by the 2 methods compared favourably in the case of ammonium but differed significantly in the case of nitrate plus nitrite. Whereas calculations based on observed gradients predict a net flux of the latter species from the sediment to the water column, experimental incubations show active uptake of nitrate and nitrite by the sediment. It was demonstrated that this uptake is biologically mediated.
AN: 2292684

                                                                   1312 of 1521  
TI: Heavy metals in Narragansett Bay sediments.
AU: Bender,-M.
AF: Off. Mar. Programs, Mar. Resour. Build., URI Narragansett Bay Campus, Narragansett, RI 02882-1197, USA
SO: MARITIMES. 1989. vol. 33, no. 4, pp. 5-7
LA: English
ER: M (Marine)
AB: Anthropogenic additions of heavy metals to Narragansett Bay from domestic and industrial activities have come to exceed the natural sources of heavy metals. This can be seen clearly by the abundance of trace metals in the water, sediments, and animals near population centers, industrial sites, and sewage discharges. The abiological behavior of metals in estuaries is largely governed by their solubility in the presence of oxygen and sulfide. When oxygen is present, as it is in estuarine waters, manganese and iron tend to form precipitates which will cause those metals to be incorporated onto particles and transferred to the sediment. When sulfide is present, as it is in estuarine sediments rich in organic debris, it will combine with metals such as copper, cadmium, zinc, and lead. The metal sulfides that form are highly insoluble and will tend to be sequestered in the sediments. Pollutant trace metals added to the Bay can, in principal, be assimilated into natural cycles. However, trace metals in the Bay have been raised to such high concentrations by pollution that their abundance far exceeds biological requirements.
AN: 2291934

                                                                   1313 of 1521  
TI: Ascending and descending fluxes of lipid compounds in North Atlantic and North Pacific abyssal waters.
AU: Grimalt,-J.O.; Simoneit,-B.R.T.; Gomez-Belinchon,-J.I.; Fischer,-K.; Dymond,-J.
AF: Dep. Environ. Chem. (CID-CSIC), Jordi Girona 18, 08034-Barcelona, Spain
SO: NATURE. 1990. vol. 345, no. 6271, pp. 147-150
LA: English
ER: M (Marine)
AB: Based on the sediment-trap experiments, the authors show that upward fluxes determine the biogeochemical cycling of some lipids in abyssal waters. Up-to-down flux ratios ranging between 0.19-190% and 15-13,000% have been found for sterols and fatty acids, respectively. The ascending organic material corresponds essentially to zooplankton and crustacean debris, whereas algal patterns dominate in the settling particles. Results indicate that formation of buoyant matter in abyssal waters may act as a selection mechanism by which some lipid components are recycled back to the upper water levels whereas others keep descending towards the bottom. This previously unreported process has implications for the interpretation of the lipid record in oceanic sediments, especially when molecular stratigraphy is used for palaeoenvironmental assessment.
AN: 2290405

                                                                   1314 of 1521  
TI: The behaviour of  super(59)Fe in marine microhabitat.
AU: Cai,-Fulong; Chen,-Ying; Xu,-Pi'-an; Qiu,-Manhua
AF: 3rd Inst. Oceanogr., SOA, Xiamen, People's Rep. China
SO: ACTA-OCEANOL.-SIN.-HAIYANG-XUEBAO. 1989. vol. 8, no. 3, pp. 423-429
LA: English
ER: M (Marine)
AB: Under artificial conditions the  super(59)Fe morphology in sea water, its concentration in sediment and phytoplankton, its distribution and metabolism in tissue organs of marine animals were studied. The results showed that the morphology of  super(59)Fe was in a particulate state in sea water. The adsorption rule of  super(59)Fe by three kinds of sediments was similar, and the concentration ability of  super(59)Fe by phytoplankton was very strong. Critical concentration organs of  super(59)Fe by marine animals were viscera, and gross radioactivity of  super(59)Fe was mainly concentrated in protein. The concentration factor of  super(59)Fe by DNA was the highest one. After excretion experiment,  super(59)Fe of all the tissue organs was not detected. A small part of  super(59)Fe remained in the organic acid and protein state. There was a redistribution process in sediment for  super(59)Fe.
AN: 2289650

                                                                   1315 of 1521  
TI: Water pollution: Pesticides in aquatic environments. January 1978-December 1989 (a bibliography from Pollution abstracts).
CA: National Technical Information Serv., Springfield, VA (USA)
SO: SPRINGFIELD,-VA-USA-NTIS 1990. 71 pp
NT: NTIS Order No.: PB90-864620/GAR. 135 refs.
LA: English
AB: This bibliography contains citations concerning the physicochemical and biochemical dynamics of pesticides in aquatic environments. The effects of organophosphorus, organochlorine, and arsenical pesticides on marine, surface, and groundwater ecosystems are discussed. Topics include biological fate and transformation of pesticides in waters, sources of release and transport of pesticides, bioaccumulation and metabolism of pesticides by aquatic organisms, ecological concentration and degradability of pesticides in model ecosystems, marine ecology, and guidelines for pesticide registration and pesticide effluents. (This updated bibliography contains 135 citations, 15 of which are new entries to the previous edition). (Supersedes PB89-853733. Prepared in cooperation with Cambridge Scientific Abstracts, Washington, DC.)
AN: 2287315

                                                                   1316 of 1521  
TI: Evidence from carbon isotope measurements for diverse origins of sedimentary hydrocarbons.
AU: Freeman,-K.H.; Hayes,-J.M.; Trendel,-J.-M.; Albrecht,-P.
AF: Biogeochem. Lab., Dep. Chem. and Geol., Geol. Build., Indiana Univ., Bloomington, IN 47405-5101, USA
SO: NATURE. 1990. vol. 343, no. 6255, pp. 254-256
LA: English
AB: The organic matter found in sedimentary rocks must derive from many sources; not only from ancient primary producers but also from consumers and secondary producers. In all of these organisms, isotope effects can affect the abundance and distribution of  super(13)C in metabolites. Here, by using an improved form of a previously described technique in which the effluent of a gas chromatograph is continuously analysed isotopically, we report evidence of the diverse origins of sedimentary organic matter. The record of  super(13)C abundances in sedimentary carbonate and total organic carbon can be interpreted in terms of variations in the global carbon cycle. Our results demonstrate, however, that isotope variations within sedimentary organic mixtures substantially exceed those observed between samples of total organic carbon. Resolution of isotope variations at the molecular level offers a new and convenient means of refining views both of localized palaeoenvironments and of control mechanisms within the global carbon cycle.
AN: 2286364

                                                                   1317 of 1521  
TI: Peatland ice/water quality.
AU: Kadlec,-R.H.; Li,-Xiang-Ming
AF: Dep. Chem. Eng., Univ. Michigan, Ann Arbor, MI 48109-2136, USA
SO: WETLANDS. 1990. vol. 10, no. 1, pp. 93-106
LA: English
ER: F (Freshwater)
AB: Freezing of the shallow water in a northern peatland caused downward movement of solutes. Nutrients and tracers were rejected from overlying water, with lesser effects in a wetland receiving treated municipal wastewater. Concentration profiles within the ice are controlled by starting concentrations and rate of freezing. High concentrations near the ice top are caused by initial fast freezing, but solute accumulations near the soil surface can cause high concentrations at the lower ice surface also. Chloride partitions most strongly; nutrients or biologically active species partition less strongly. Complex mass and energy balance calculations can provide reasonable estimates of chloride concentrations, but sufficient field data would rarely be available to execute detailed predictions for other ions. Processes involving ice are important in the reallocation of dissolved species within peatlands. Ice formation can cleanse a closed-basin wetland once each year.
AN: 2285855

                                                                   1318 of 1521  
TI: Methods of studies of aquatic microorganisms.
OT: Metody izucheniya vodnykh mikroorganizmov
AU: Kuznetsov,-S.I.; Dubinina,-G.A.
SO: MOSKVA-USSR-NAUKA 1989. 288 pp
NT: Incl. bibliogr.: 426 ref.
LA: Russian
AB: The book falls into 3 parts dealing with: 1) traditional and new methods of the "in vivo" and "in vitro" studies of aquatic microorganisms; 2) cultivation and counting of major groups of microorganisms participating in C, N, S, Fe and Mn cycles in water bodies and 3) estimation of intensity of microbiological processes.
AN: 2285680

                                                                   1319 of 1521  
TI: Coagulation on bubbles allows microbial respiration of oceanic dissolved organic carbon.
AU: Kepkay,-P.E.; Johnson,-B.D.
AF: Biol. Oceanogr. Div., Dep. Fish. and Oceans, Bedford Inst. Oceanogr., Dartmouth, N.S. B2Y 4A2, Canada
SO: NATURE. 1989. vol. 338, no. 6210, pp. 63-65
LA: English
ER: M (Marine)
AB: Dissolved organic carbon in sea water (DOC) is one of the chief reservoirs of reactive organic carbon on the planet. To determine the rate at which this carbon breaks down, a long standing paradox must be solved. DOC appears to be remarkably unreactive, yet it must be reactive to maintain the mass balance between organic carbon in the ocean and CO sub(2) in the atmosphere. It is shown that the coagulation of colloidal DOC on bubble surfaces initiates the rapid microbial respiration of carbon which would otherwise be less accessible to the biota. This coupling of respiration to surface coagulation as a physical means of regenerating a substantial fraction (5-15%) of oceanic DOC could be a key factor in the mechanism required to recycle a recalcitrant reservoir of carbon back to CO sub(2).
AN: 2284651

                                                                   1320 of 1521  
TI: Water filtration by dissipative beaches.
AU: McLachlan,-A.
AF: Oregon Inst. Mar. Biol., Univ. Oregon, Charleston, SC 97420, USA
SO: LIMNOL.-OCEANOGR. 1989. vol. 34, no. 4, pp. 774-780
LA: English
ER: M (Marine)
AB: Dissipative or low-gradient beaches are expected to filter low volumes of seawater. This idea was tested on the Oregon coast on two high-energy dissipative beaches with medium and fine sand and found to be correct, filtered volumes being 0.1-7 m super(3)/m/d. Input was mainly due to tidal effects as most wave energy was dissipated in the surf zone. During a very high-energy event on a high tide, however, filtered volume increased by an order of magnitude as a consequence of increased wave input.
AN: 2283494

                                                                   1321 of 1521  
TI: Kinetics of dissolution of Antarctic diatom frustules and the biogeochemical cycle of silicon in the Southern Ocean.
AU: Treguer,-P.; Kamatani,-A.; Gueneley,-S.; Queguiner,-B.
AF: Lab. Chim. Ecosyst. Mar., Inst. Etud. Mar., Univ. Bretagne Occidentale, F-29287 Brest-Cedex, France
SO: POLAR-BIOL. 1989. vol. 9, no. 6, pp. 397-403
NT: 47 ref.
LA: English
ER: M (Marine)
AB: The objectives of this work are: 1) measuring the dissolution rates of biogenic silica for specific and natural assemblages of Antarctic diatoms, at conditions prevailing in Antarctic surface waters during summer; 2) simulating the fate of the biogenic silica particles settling down through the cold and turbulent waters of the Circumpolar Current.
AN: 2279767

                                                                   1322 of 1521  
TI: Annual cycles and budget of nutrients in Berre Lagoon (Mediterranean Sea, France).
AU: Arfri,-R.
AF: Cent. Oceanol. Marseille, (UA 41), Fac. Sci. Luminy, Marseille, France
SO: INT.-REV.-GESAMT.-HYDROBIOL. 1989. vol. 74, no. 1, pp. 29-49
LA: English
ER: B (Brackish)
AB: The annual cycles of nutrients in the Etang de Berre were studied in 1985. An estimation is proposed for a nutrient budget. Seasonal variability is important, and a biological control of nutrient availability (locally remineralized products) results in a hydrologically controlled system (nutrients carried by continental waters) which produces the very high microalgal biomass in the lagoon. The seasonal halocline brings the euphotic layer very close to the remineralization site. Nutrients are then constantly available to the phytoplankton.
AN: 2274966

                                                                   1323 of 1521  
TI: Microbial utilization of naturally occurring hydrocarbons at the Guaymas Basin hydrothermal vent site.
AU: Bazylinski,-D.A.; Wirsen,-C.O.; Jannasch,-H.W.
AF: Biol. Dep., Woods Hole Oceanogr. Inst., Woods Hole, MA 02543, USA
SO: APPL.-ENVIRON.-MICROBIOL. 1989. vol. 55, no. 11, pp. 2832-2836
LA: English
ER: M (Marine)
AB: The Guaymas Basin (Gulf of California; depth, 2,000 m) is a site of hydrothermal activity in which petroliferous material is formed by thermal alteration of deposited planktonic and terrestrial organic matter. The authors investigated certain components of these naturally occurring hydrocarbons as potential carbon sources for a specific microflora at these deep-sea vent sites. Respiratory conversion of (1- super(14)C)hexadecane and (1(4,5,8)- super(14)C)naphthalene to  super(14)CO sub(2) was observed at 4 degree C and 25 degree C, and some was observed at 55 degree C, but none was observed at 80 degree C. Bacterial isolates were capable of growing on both substrates as the sole carbon source. All isolates were aerobic and mesophilic with respect to growth on hydrocarbons but also grew at low temperatures (4 to 5 degree C). These results correlate well with previous geochemical analyses, indicating microbial hydrocarbon degradation, and show that at least some of the thermally produced hydrocarbons at Guaymas Basin are significant carbon sources to vent microbiota.
AN: 2271250

                                                                   1324 of 1521  
TI: Sulfur-containing amino acids as precursors of thiols in anoxic coastal sediments.
AU: Kiene,-R.P.; Malloy,-K.D.; Taylor,-B.F.
AF: Rosenstiel Sch. Mar. and Atmos. Sci., Univ. Miami, 4600 Rickenbacker Causeway, Miami, FL 33149-1098, USA
SO: APPL.-ENVIRON.-MICROBIOL. 1990. vol. 56, no. 1, pp. 156-161
LA: English
ER: M (Marine)
AB: Sulfur-containing amino acids were examined as precursors for thiols in anoxic coastal sediments. Substrates (10 to 100  mu M) were anaerobically incubated with sediment slurries; thiols were assayed as isoindole derivatives by high-performance liquid chromatography; and microbial transformations of thiols, in contrast to their chemical binding by sediment particles, were identified by inhibition with a mixture of chloramphenicol and tetracycline. Methionine and homocysteine were transformed to methanethiol and 3-mercaptopropionate (3-MPA); methionine stimulated mainly methanethiol production, whereas homocysteine generated more 3-MPA than methanethiol. 2-Keto-4-methiolbutyrate yielded results similar to those with methionine, indicating that demethiolation yields methanethiol at the keto-acid level. Glutathione gave rise to cysteine, which was further transformed to 3-mercaptopyruvate and thence to mercaptoacetate and mercaptoethanol. Mercaptoethanol was oxidized to mercaptoacetate, which was biologically consumed.
AN: 2271162

                                                                   1325 of 1521  
TI: Marine microbiology: A need for deep-sea diving?.
AU: Jannasch,-H.W.
AF: Woods Hole Oceanogr. Inst., Woods Hole, MA 02543, USA
SO: MAR.-TECHNOL.-SOC.-J. 1990. vol. 24, no. 2, pp. 38-41
NT: Special issue: A deepest ocean presence.
LA: English
ER: M (Marine)
AB: Studies in deep-sea microbiology are an essential part of global biogeochemistry and of biological oceanography in particular. Discovering the heterogeneity of microbial populations and their activities on the deep-sea floor was not possible without the capability of visual surveying and sample collecting during manned diving operations. This lack of uniformity not only refers to hydrothermal vents and cold seeps but also to the discontinuous accumulations of organic deposits in seafloor depressions at a large range of scales and the resulting formation of nutrient enriched anoxic pockets. Free-vehicles have aided in this work. The rapid developments of ROV capabilities promise wide geographical spread of microbial deep-sea studies. In planning to extend our diving operations to the oceans' maximum depths, the simultaneous development and use of all of these approaches will be essential, and it is greatly hoped that economic consideration will not force us into making premature choices.
AN: 2270920

                                                                   1326 of 1521  
TI: Biological research needs for submersible access to the greatest ocean depths.
AU: Robison,-B.H.; Wishner,-K.
AF: Monterey Bay Aquar. Res. Inst., Pacific Grove, CA, USA
SO: MAR.-TECHNOL.-SOC.-J. 1990. vol. 24, no. 2, pp. 34-37
NT: Special issue: A deepest ocean presence.
LA: English
ER: M (Marine)
AB: Despite the availability of DSV Alvin  to the oceanographic community, the great majority of the living space in the deep sea is not accessible to researchers. Based on what we have learned from submersible work within Alvin's  4 km depth range, conventional sampling methods such as trawls and dredges give a restricted and biased view of both pelagic and benthic ecology. This paper presents a preliminary outline of biological research topics to be conducted by submersibles in deep water. In the deep water column we need to assess the identities, abundances, and small-scale distribution patterns of the constituent midwater fauna. At the benthic boundary layer we need to study biogeochemical cycling and the energetic coupling between pelagic and benthic communities. On the deep seafloor we need to investigate the variability of faunal distributions and abundances, in steady state and in response to a variety of perturbations. In all of these deep habitats we need to study the dynamic, functional aspects of ecology that can only be examined through direct observations and sampling.
AN: 2268895

                                                                   1327 of 1521  
TI: Dynamics of mineral phosphate in water column in the East Pacific.
OT: Dinamika mineral'nogo fosfata v tolshche vody vostochnoj chasti Tikhogo okeana
AU: Sorokin,-Yu.I.
AF: Yuzhn. Otd. IOAN SSSR, Gelendzhik, USSR
SO: OKEANOLOGIYA-OCEANOLOGY-MOSC.. 1990. vol. 30, no. 1, pp. 70-77
LA: Russian
ER: M (Marine)
AB: The total intensity of PO sub(4)-P consumption by microplankton (A sub(t)) is shown to reach maximum values (150-280 ng/l/h) in upwelling zone and in the zone of phytoplankton bloom caused by this upwelling at the Peruvian section. In other areas of this section in surface water layers it constituted 40-80 ng/l. In waters of lower productivity of Central American and Californian sections it decreased to 20-40 ng/l. At the vertical profile A sub(t) maxima were recorded at upper boundary of thermocline. In the zones of phytoplankton bloom 60-80% of total PO sub(4)-P consumption is accounted for phytoplankton. In the zones of enhanced bacteria number phytoplankton share in PO sub(4)-P total consumption decreased to 20-40%. Data are presented to show absence of correlation between PO sub(4)-P concentration in water and productivity level. It is emphasized that the above parameters of PO sub(4)-P dynamics can be used to obtain characteristics of functional state and succession phase of development of marine plankton communities.
AN: 2267823

                                                                   1328 of 1521  
TI: Particulate organic carbon of the south-eastern portion of the South China Sea.
AU: Ichikawa,-T.; Law,-A.T.
AF: Dep. Biol., Fac. Sci., Kagoshima Univ., Korimoto, Kagoshima 890, Japan
SO: EKSPEDISI-MATAHARI-'-87:-A-STUDY-ON-THE-OFFSHORE-WATERS-OF-THE-MALAYSIAN-EEZ. Mohsin,-A.K.M.;Mohamed,-M.I.H.-eds. 1988. no. 8 pp. 37-42
ST: OCCAS.-PUBL.-FAC.-FISH.-MAR.-SCI.-UNIV.-PERTANIAN-MALAYS. no. 8
LA: English
ER: M (Marine)
AB: Particulate organic carbon in sea water was measured in samples collected in the waters off West Malaysia (Borneo) during the cruise of R.V. Kagoshima-Maru  (Matahari Expedition '87). The carbon concentrations at 16 stations changed from 54 to 142  mu gC/l. The integrated amount of particulate organic carbon in the water column (0-50 m) at each station was in the range 3.7 to 6.0 gC/m super(2).
AN: 2266559

                                                                   1329 of 1521  
TI: The effect of iron nutrition on photosynthesis and nitrogen fixation in cultures of Trichodesmium  (Cyanophyceae).
AU: Rueter,-J.G.; Ohki,-K.; Fujita,-Y.
AF: Dep. Biol., Portland State Univ., Portland, OR 97207-0751, USA
SO: J.-PHYCOL. 1990. vol. 26, no. 1, pp. 30-35
LA: English
ER: M (Marine)
AB: Cultures of Trichodesmium  NIBB 1067 were grown in the synthetic medium AQUIL with a range of iron added from none to 5 x 10 super(-7) M Fe for 15 days. Chlorophyll-a cell counts, and total cell volume were two or three times higher in medium with 10 super(-7) M Fe than with no added Fe. Oxygen production rate per chlorophyll-a was over 60% higher with higher iron. Increased iron stimulated photosynthesis at all irradiances from about 12-250  mu E/m super(2)/s. Nitrogen fixation rate, estimated from acetylene reduction, for 10 super(-7) and 10 super(-8) M Fe cultures was approximately twice that of the cultures with no added Fe. The range of rates of O sub(2) production and N sub(2) fixation in cultures at the iron concentrations used were similar to the rates from natural samples of Trichodesmium) from both the Atlantic and the Pacific oceans. This similarity may allow this clone to be used, with some caution, for future physiological ecology studies. This study demonstrates the importance of iron to photosynthesis and nitrogen fixation and suggests that Trichodesmium  plays a central role in the biogeochemical cycles of iron, carbon and nitrogen.
AN: 2261352

                                                                   1330 of 1521  
TI: Dimethylsulfide and the alga Phaeocystis pouchetii  in Antarctic coastal waters.
AU: Gibson,-J.A.E.; Garrick,-R.C.; Burton,-H.R.; McTaggart,-A.R.
AF: Australian Antarctic Div., Channel Highw., Kingston, Tas. 7050, Australia
SO: MAR.-BIOL. 1990. vol. 104, no. 2, pp. 339-346
NT: 43 ref.
LA: English
ER: M (Marine)
AB: The concentrations of dimethylsulfide (DMS), dimethyl-sulfoniopropionate (DMSP) and dimethylsulfoxide (DMSO) were measured in water collected from the Southern Ocean 10 km offshore from Davis Station, Antarctica, during the period May 1987 to Jan 1988, inclusive. During winter and spring, when the sea-ice was up to 1.9 m thick, DMS, DMSP and DMSO concentrations were low (0.2 to 1.5 nM), as were phytoplankton numbers. The maximum concentration of the sulfur compounds generally occurred in top 10 m of the water column. DMS levels rose dramatically from early Dec onwards, reaching a peak of 290 nM at a depth of 15 m in Jan. This concentration is higher than reported elsewhere in the ocean. These high concentrations occurred at the same time as a bloom of the alga Phaeocystis pouchetii . A significant correlation occurred between DMS concentration and cell numbers of the alga.
AN: 2260449

                                                                   1331 of 1521  
TI: What happens to zooplankton faecal pellets? Implications for material flux.
AU: Lampitt,-R.S.; Noji,-T.; Bodungen,-B.-von
AF: Inst. Oceanogr. Sci., Deacon Lab., Wormley, Godalming, Surrey GU8 5UB, UK
SO: MAR.-BIOL. 1990. vol. 104, no. 1, pp. 15-23
NT: 51 ref.
LA: English
ER: M (Marine)
AB: In 1987/1988 we carried out experiments using adult copepods of mixed species but dominated by Centropages hamatus  collected in Kiel Bight (FRG). We have demonstrated that copepods can be highly adept at breaking up their own pellets while ingesting only a small proportion, a behaviour we define as "coprorhexy". The microbiota is probably unable to cause significant modification to faecal pellets before they are fragmented within a few hours of their production. Thereafter, microbial remineralisation will become important. Many of the "difficult" field data can be readily explained if the process of coprorhexy is taken into account and, indeed, breakage of large particles by crustacean zooplankton may be an important process in modifying material transport in the ocean. Copepods appear to perform coprorhexy by removing the peritrophic membrane with its attached bacterial flora and this may then be ingested.
AN: 2260301

                                                                   1332 of 1521  
TI: Extracellular organic carbon (EOC) in the genus Carpophyllum  (Phaeophyceae): Diel release patterns and EOC lability.
AU: Soendergaard,-M.
AF: Inst. Life Sci. and Chem., Roskilde Univ., P.O. Box 260, DK-4000 Roskilde, Denmark
SO: MAR.-BIOL. 1990. vol. 104, no. 1, pp. 143-151
NT: 37 ref.
LA: English
ER: M (Marine)
AB: Release of extracellular organic carbon (EOC) by the four species of the brown algal genus Carpophyllum  was investigated in light:dark incubations of 30 to 40 h duration using a  super(14)C-method. Plants were collected during 1986 in the Hauraki Gulf area, Auckland, New Zealand. In C. maschalocarpum  and C. plumosum  rather low release rates in light (2 to 5% of the photosynthetic rates) were followed by high release rates after 4 to 5 h in darkness (10 to 15% of previous photosynthetic rates). The opposite pattern, with high release in light and low in darkness, was found in experiments with C. angustifolium  and C. flexuosum . The pattern with substantially higher release in dark than in light is observed for the first time. EOC products were dominated by small molecules (< 1000 daltons) in all four species and both in light and darkness.
AN: 2260142

                                                                   1333 of 1521  
TI: Interaction between supply of nutrients, primary production, sedimentation and oxygen consumption in SE Kattegat.
AU: Rydberg,-L.; Edler,-L.; Floderus,-S.; Graneli,-W.
AF: Inst. Oceanogr., Box 4038, S-400 40 Goeteborg, Sweden
SO: AMBIO. 1990. vol. 19, no. 3, pp. 134-141
NT: Special issue: Marine eutrophication.
LA: English
ER: M (Marine)
AB: Intensive measurements of nutrient fluxes, carbon and nitrogen assimilation, sedimentation and oxygen consumption within the SE Kattegat are used in an effort to follow the coupling between increasing nutrient supply and decreasing deep-water oxygen concentrations. The investigated area is a part of the strongly stratified Baltic estuary, with a hampered deep-water exchange and a large supply of nitrogen from nearby anthropogenic sources. Measurements were undertaken during 1981-1988. The results are discussed, mainly in terms of annual or seasonal mean values. The average primary production, 11.4 mol C/m super(2) was surprisingly well correlated with the uptake of inorganic nitrogen, which averaged 1.68 mol N/m super(2) (11.1 mol C/m super(2), using the Redfield ratio). The oxygen consumption (deep water and benthic) which averaged 20 mol O sub(2)/m super(2)/d, was well correlated  both with the measured nitrate uptake and with the external supply of nitrate to the surface water.
AN: 2257934

                                                                   1334 of 1521  
TI: Nutrient dynamics of the Baltic Sea.
AU: Wulff,-F.; Stigebrandt,-A.; Rahm,-L.
AF: Askoe Lab., Univ. Stockholm, S-106 91 Stockholm, Sweden
SO: AMBIO. 1990. vol. 19, no. 3, pp. 126-133
NT: Special issue: Marine eutrophication.
LA: English
ER: M (Marine)
AB: A prerequisite for understanding the large-scale eutrophication of the Baltic Sea is an understanding of the factors responsible for regional and long-term variations of nutrients. This article summarizes recent studies on the changes in overall total amounts and the distribution pattern of nutrients. The total amounts of phosphorus and nitrogen have increased over the last few decades. On the other hand, silicate levels have been decreasing, indicating a higher net primary production and sedimentation of diatoms. A series of models has been used to test our present understanding of the critical processes controlling nutrient and oxygen conditions. It is shown that a few morphometric factors are essential, like shallow sill depth at the entrance of the estuarine-like sea and shallow mean depth. It is also shown that phosphorus, nitrogen and silicate differ in terms of residence times and their response to external loading.
AN: 2257815

                                                                   1335 of 1521  
TI: (Transformation of organic and biogenic matters under anthropogenic eutrophication of lakes.).
OT: Transformatsiya organicheskogo i biogennykh veshchestv pri antropogennom ehvtrofirovanii ozer
AU: Drabkova,-V.G.; Stravinskaya,-E.A.-(eds.)
SO: LENINGRAD-USSR-NAUKA 1989. 270 pp
NT: Incl. bibliogr.: 254 ref.
LA: Russian
ER: F (Freshwater)
AB: The intensity of productional and destructional processes as dependent on arrival and transformation of biogenic matters is estimated with reference to the lakes of Latgal upland (eastern Latvia) subjected to man-induced effects. The arrival of P and N from bottom sediments is shown to be an important factor responsible for the content of these substances in water. The relationship between inner and outer biogenic load on the lakes is presented. The intensity of P consumption and regeneration by biological communities of different trophic levels in water and lake bottom sediments is considered.
AN: 2255241

                                                                   1336 of 1521  
TI: Optical modeling of the upper ocean in relation to its biogenous matter content (case 1 water).
AU: Morel,-A.
AF: Lab. Phys. et Chim. Mar., Univ. Pierre et Marie Curie, Villefranche-Sur-Mer, France
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1988. vol. 93, no. C9, pp. 10749-768
LA: English
ER: M (Marine)
AB: The aim of the present study is to review and tentatively to interpret the optical behavior of oceanic case 1 waters, those waters for which phytoplankton and their derivative play a predominant role in determining their optical properties. Chlorophyll-like pigment concentration is used as the index to quantify the algal material (living and detrital), and statistical relationships between this index and the depth of the euphotic layer, the spectral values of the attenuation coefficient for downwelling irradiance, or the scattering coefficient are investigated. On the basis of these statistical relationships a pigment-dependent optical model is developed. Other geophysical or geochemical applications are derived which concern the heating rate due to penetrating visible radiations or the rate of energy storage due to photosynthesis.
AN: 2239550

                                                                   1337 of 1521  
TI: (Tin and organotins in the marine environment: Biogeochemistry and ecotoxicology.).
OT: L'etain et les organoetains en milieu marin: Biogeochimie et ecotoxicologie
AU: Alzieu,-C.
AF: IFREMER, Cent. Nantes, BP 1049, 44037 Nantes Cedex, France
SO: RAPP.-SCI.-TECH.-IFREMER. PLOUZANE-FRANCE-IFREMER,-CENT.-BREST,-SERVICE-DOCUMENTATION-and-PUBLICATION 1989. no. 17, 93 pp
LA: French
ER: M (Marine)
AB: This report synthesizes the knowledge on the biogeochemical cycle, bioconcentration processes and ecotoxicity of tin and organotins in the marine environment. Concentrations levels, biomethylation mechanisms and exchanges between sediments and water are assessed. Emphasis is given on tributyltin sublethal effects, toxicity mechanisms and no effect levels for the most sensitive organisms. Regulations on the use of organotins as antifoulants in paints are examined. Conclusions and recommendations for environmental management and research are given.
AN: 2232000

                                                                   1338 of 1521  
TI: (Cadmium in marine environment.).
OT: Le cadmium en milieu marin
AU: Cossa,-D.; Lassus,-P.
AF: IFREMER, Cent. Nantes, Rue de l'Ile d'Yeu, BP 1049, 44037 Nantes Cedex 01, France
SO: RAPP.-SCI.-TECH.-IFREMER. PLOUZANE-FRANCE-IFREMER,-CENT.-BREST,-SERVICE-DOCUMENTATION-and-PUBLICATION 1989. no. 16, 112 pp
LA: French
ER: M (Marine)
AB: This report synthesizes the knowledge on the biogeochemical cycle, bioconcentration processes and ecotoxicity of cadmium in the marine environment. Man induced changes on the cadmium cycle, especially along the French coasts are reviewed. Concentration levels, mechanisms and fluxes between geochemical reservoirs are assessed. Emphasis is given on sublethal effects and toxicity mechanisms. Quality standards used in European Community countries are listed. Conclusions and recommendations for environmental management and research are given.
AN: 2231970

                                                                   1339 of 1521  
TI: Organic matter degradation and nutrient regeneration in Australian freshwaters: 1. Methods for exoenzyme assays in turbid aquatic environments.
AU: Boon,-P.I.
AF: Murray-Darling Freshwater Res. Cent., P.O. Box 921, Albury, N.S.W. 2640, Australia
SO: ARCH.-HYDROBIOL. 1989. vol. 115, no. 3, pp. 339-359
NT: Bibliogr.: 44 ref.
LA: English
ER: F (Freshwater)
AB: A method was developed using p-nitrophenol and p-nitroaniline derivatives to measure exoenzyme activity in turbid waters. Maximum activity occurred at temperatures of 40 degree C or above. The response to variations in pH was complex, with some systems showing no clear optimum but others showing an optimum at either pH of 7.5 or pH 9.0-10.0. Only 25% of the enzyme system-site combinations generated linear Lineweaver-Burke plots, indicating that many exoenzyme systems were active simultaneously in the degradation of organic detritus. The maximum rate of activity occurred with aminopeptidase (up to 107  mu mol/l/d), followed by alkaline phosphatase (up to 42  mu mol/l/d). There was little lipase or  alpha -D glucosidase activity in the any water body, except in a highly-eutrophied lagoon. Rates were consistently higher in billabongs than in rivers, and most activity was associated with particles rather than being free in the water column.
AN: 2225377

                                                                   1340 of 1521  
TI: New production and export of organic matter to the deep ocean: Consequences of some recent discoveries.
AU: Legendre,-L.; Gosselin,-M.
AF: Dep. Biol., Univ. Laval, Ste-Foy, Que. G1K 7P4, Canada
SO: LIMNOL.-OCEANOGR. 1989. vol. 34, no. 7, pp. 1374-1380
LA: English
ER: M (Marine)
AB: It is generally accepted that planktonic new production is equivalent to the export of particulate organic matter (POM) to the deep ocean. The difference between new (P sub(N)) and total (P sub(T)) primary production is regenerated production (P sub(R)), which is fueled by nutrients regenerated in surface waters by the heterotrophic food web. New and regenerated production in the euphotic zone can be estimated from the uptake of  super(15)N-labeled nitrate (P sub(N)) and that of ammonia and urea (P sub(R)). The ratio of new to total production (P sub(N):P sub(T)), when estimated independently can be used to computer P sub(N) from P sub(T) in cases where the latter has been measured directly (e.g. from photosynthetic assimilation of  super(14)C-labeled CO sub(2)).
AN: 2221552

                                                                   1341 of 1521  
TI: Influence of coupling of sorption and photosynthetic processes on trace element cycles in natural waters.
AU: Fuller,-C.C.; Davis,-J.A.
AF: Water Resour. Div., U.S. Geol. Surv., Menlo Park, CA 94025, USA
SO: NATURE. 1989. vol. 340, no. 6228, pp. 52-54
LA: English
ER: F (Freshwater)
AB: We have studied the effect of diurnal cycling of pH on dissolved arsenate in a perennial stream contaminated with arsenic. As expected, a diurnal cycle in arsenate concentration was observed, but surprisingly, the arsenate cycle lags several hours behind the pH cycle. Laboratory experiments show that the lag results from a slow approach to sorption equilibrium. Our observations demonstrate that the coupling of photosynthesis and sorption processes may have an important influence on the cycling of many trace elements and emphasize the importance of understanding sorption kinetics in modelling these processes.
AN: 2220988

                                                                   1342 of 1521  
TI: Upon the role of vegetation in sulfur storage in mangrove soils (Senegal). Preliminary results.
OT: Sur le role de la vegetation dans le stockage du soufre dans les sols de mangrove (Senegal). Resultats preliminaires
AU: Feller,-C.; Trichet,-J.; Fontes,-J.C.; Marius,-C.
AF: ORSTOM, c/o CPB-CNRS, LP 6831, Assoc. Univ. Nancy I, BP 5, 54501 Vandoeuvreles-Nancy Cedex, France
SO: SOIL-BIOL.-BIOCHEM. 1989. vol. 21, no. 7, pp. 947-952
LA: English
ER: B (Brackish)
AB: Plant organs, plant residues at different degrees of decomposition, and the surface soil (0-5 cm) of a Rhizophora  mangrove in Saloum Island (Senegal) were analyzed for total C, N, S and amino acid content and for sulfur isotopical composition ( delta  super(34)S). These preliminary results emphasize the possible role of vegetation (roots and leaves) on S storage in mangrove soils.
AN: 2220692

                                                                   1343 of 1521  
TI: Aspects of the phosphorus cycle in Hartbeespoort Dam (South Africa). Phosphorus kinetics.
AU: Thornton,-J.A.
AF: City Planner's Dep., Cape Town City Counc., P.O. Box 1694, Cape Town 8000, South Africa
SO: HYDROBIOLOGIA. 1989. vol. 183, no. 2, pp. 87-95
LA: English
ER: F (Freshwater)
AB: The role of biotic processes in a warm, monomictic, hypertrophic African impoundment (Hartbeespoort Dam) is examined using  super(32)P radiobioassays. Phosphorus demand is assessed by phosphorus turnover times, alkaline phosphatase activity, cellular phosphorus status and the phosphorus deficiency index. Long turnover times indicative of an enriched system were recorded, ranging from 9 h to 1992 h, with no evidence of phosphorus stress being present. These turnover times support the hypothesis that the phosphorus cycle in Hartbeespoort Dam is dominated by the algal community which is shown to play an important role in phosphorus cycling within the water column. However, hydrological processes remain the driving force in phosphorus seasonality in the lake.
AN: 2216536

                                                                   1344 of 1521  
TI: A model of biogeochemical cycling of phosphorus, nitrogen, oxygen, and sulphur in the ocean: One step toward a global climate model.
AU: Shaffer,-G.
AF: Oceanogr. Inst., Univ. Gothenburg, Gothenburg, Sweden
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1989. vol. 94, no. C2, pp. 1979-2004
LA: English
ER: M (Marine)
AB: A ocean model is developed which, for prescribed physics, deals with interrelationships between chemical distributions, biogeochemical sinks and sources, chemical reactions at redox fronts, and transport across the air-sea and sediment-water interfaces. The model focuses on biogeochemical cycling of phosphorus, nitrogen, oxygen, and sulphur in an ocean forced by river input of nutrients. This is a natural starting point for a global climate model since ocean circulation and biology determine atmospheric CO sub(2) concentrations for a given inventory of inorganic C and oceanic production is controlled mainly by the availability to inorganic P and/or N. A general approach is taken to look at oxic versus anoxic conditions, P versus N limitation of primary production, with or without inorganic removal of phosphate to the sediments. Chemical species considered are PO sub(4) super(3-)-P, NO sub(3) super(-)-N, O sub(2), NH sub(4) super(+)-N and H sub(2)S-S. Results indicate that a change from oxic to weakly anoxic conditions at middepths in a P-limited ocean would lead to strong local denitrification and low nitrate concentrations throughout the water column.
AN: 2215036

                                                                   1345 of 1521  
TI: Vertical fluxes of nitrate associated with salt fingers in the world's oceans.
AU: Hamilton,-J.M.; Lewis,-M.R.; Ruddick,-B.R.
AF: Phys. Chem. Sci., Bedford Inst. Oceanogr., Dartmouth, N.S., Canada
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1989. vol. 94, no. C2, pp. 2137-2145
LA: English
ER: M (Marine)
AB: The primary means by which the oceans serve as a sink for atmospheric carbon dioxide is through the vertical flux of sinking organic carbon derived from primary photosynthetic production in the upper ocean. Its rate of loss to the deep sea, the "new production", is rigorously constrained by the upward flux of the limiting nutrient, nitrate. New production estimates have been made by using velocity microstructure measurements to infer nitrate fluxes, where it is assumed that turbulent production (mixing) balances viscous energy dissipation. However, estimates based on a salt finger convection model lead to nitrate fluxes which are as much as an order of magnitude larger than a turbulent mixing model predicts and agree much better with fluxes inferred from biological uptake measurements and tracer studies. Heat flux estimates are higher by less than a factor of 3. Observations of the "scaled dissipation ratio"  Gamma , based on velocity and temperature microstructure, may provide a means of distinguishing between the 2 mixing hypotheses. Where both turbulent production and salt fingering contribute to the mixing this distinction is more difficult, but by using measurements of  Gamma  the potential error in the vertical flux estimate due to an improper choice of mixing models is greatly reduced.
AN: 2214051

                                                                   1346 of 1521  
TI: Geochemical considerations on trace element distributions in suspended matter and sediments at the river-sea interface, Adige River mouth, northern Adriatic Sea.
AU: Boldrin,-A.; Juracic,-M.; Menegazzo-Vitturi,-L.; Rabitti,-S.; Rampazzo,-G.
AF: Mar. Biol. Inst., CNR, 30122, Venezia, Italy
SO: APPL.-GEOCHEM. 1989. vol. 4, no. 4, pp. 409-421
LA: English
ER: B (Brackish)
AB: The particulate matter at the Adige River mouth has been investigated in order to determine the natural geochemical processes in the estuarine environment, and the anthropogenic influence on the biogeochemical cycling of heavy metals. The determination of suspended matter and sediment physicochemical characteristics (grain size, mineralogy, organic matter content, specific surface area), and of concentrations of major and trace elements in the Adige River mouth in different hydrological conditions, has shown that this mouth acts as a trap for most heavy metals. Moderate anthropogenic influence on Cu, Pb, Cd, and Cr concentrations has been recognised in the Adige River. The environmental fate of these elements is determined by the same natural processes, and therefore accumulation in front of the river mouth occurs.
AN: 2213983

                                                                   1347 of 1521  
TI: Parametrization of nutrient sources and discharge in the ocean.
OT: Parametrizatsiya istochnikov i stokov biogenov v okeane
AU: Ryabchenko,-V.A.
AF: Otd. IOAN AN SSSR, Leningrad, USSR
SO: METEOROL.-GIDROL. 1990. no. 2, pp. 78-87
LA: Russian
ER: M (Marine)
AB: A simple seasonal model of an ecosystem of the upper quasihomogeneous layer of the ocean is constructed and verified with reference to the results of observations available. The sensitivity of the model to representation of poorly-known parameters is investigated and their optimum values are determined. The model is shown to reflect satisfactory the seasonal variability in biological sources and discharge of nutrients and it can be employed in global models describing nutrient distribution in the ocean.
AN: 2209496

                                                                   1348 of 1521  
TI: Comparison of detritus dynamics in two tidal freshwater wetlands.
AU: Findlay,-S.; Howe,-K.; Austin,-H.K.
AF: Inst. Ecosyst. Stud., New York Bot. Gard., Mary Flagler Cary Arbor., Millbrook, NY 12545, USA
SO: ECOLOGY. 1990. vol. 71, no. 1, pp. 288-295
LA: English
ER: F (Freshwater)
AB: The authors have examined the generation and persistence of detritus in two contrasting tidal freshwater wetlands on the Hudson River. These wetlands offer a difference in vegetation, with Tivoli South Bay dominated by a floating-leafed macrophyte (water-chestnut, Trapa natans ) and North Bay a typical Typha  marsh. In South Bay, there was a large amount of water-chestnut dry biomass (400 g/m super(2)) available to enter the detritus pool, but there was no increase in the standing stock of benthic organic matter following senescence of water-chestnut. Estimates show that mineralization plus leaching of dissolved material are sufficient to remove much of the detritus. In the Typha) marsh, there is a large amount of detritus generated ( approximately equals 25% of annual primary production) and this material persists as a thick litter layer.
AN: 2207208

                                                                   1349 of 1521  
TI: The influence of different litter bag designs on the breakdown of leaf material in a small mountain stream.
AU: Stewart,-B.A.; Davies,-B.R.
AF: Freshwater Res. Unit, Zool. Dep., Univ. Cape Town, Rondebosch, South Africa
SO: HYDROBIOLOGIA. 1989. vol. 183, no. 2, pp. 173-177
LA: English
ER: F (Freshwater)
AB: Leaf breakdown of two riparian tree species, Cunonia capensis  L. and Ilex mitis  (L.) Radlk. was investigated in vitro at Window Stream, Table Mountain, using three different designs of litter bag. Breakdown of Cunonia  and Ilex  in coarse-mesh (5 mm) litter bags was very rapid (respectively 14.79 and 13.93% loss d super(-1)), and was significantly greater than the loss of leaf material of 1% d super(-1) for both species from fine-mesh bags (180  mu m). Differences recorded between fine-mesh and composite-mesh bags (180  mu m mesh with 5 mm mesh top) represented macro-invertebrate ingestion, and at t = 28 d, amounted to 67.57% material loss in Cunonia  and 62.58% in Ilex . The losses due to microbial activity and leaching, 31.28% in Cunonia  and 29.17% in Ilex  were not significantly different. Future leaf breakdown experiments in mountain streams must take cognisance of differential fragmentation losses before inferences can be made as to both invertebrate feeding preferences and biological decomposition of leaves.
AN: 2207157

                                                                   1350 of 1521  
TI: Storage and dynamics of subsurface detritus in a sand-bottomed stream.
AU: Metzler,-G.M.; Smock,-L.A.
AF: Dep. Biol., Virginia Commonwealth Univ., Richmond, VA 23284, USA
SO: CAN.-J.-FISH.-AQUAT.-SCI. 1990. vol. 47, no. 3, pp. 588-594
NT: Incl. bibliogr.: 28 ref.
LA: English
ER: F (Freshwater)
AB: Annual mean storage of buried detritus (0-20 cm depth) in a first-order, sand-bottomed stream was 4.8 kg AFDM/m super(2), approximately one order of magnitude greater than surface storage. Forty percent of the buried detritus was wood > 8 mm; much of the remainder was 1-8 mm particles. Exchange of detritus between surface and shallow sediments occurred throughout the year; exchange between surface and deep sediments occurred only during spates. About 21% of estimated autumnal leaf input to the stream became buried. Given the large quantity of detritus stored in the subsurface, its slow processing rate and the episodic nature of its release from deep storage, the hyporheic area of this stream has an important effect on the stream's carbon spiralling length, energetics, and trophic dynamics.
AN: 2207130

                                                                   1351 of 1521  
TI: Low molecular weight carboxylic acids in the sea. Photooxidative production and biological cycling.
AU: Mopper,-K.
CA: Miami Univ., FL (USA). Rosenstiel Sch. of Marine and Atmospheric Sciences
SO: 1987. 5 pp
NT: NTIS Order No.: AD-A189 748/7/GAR. Contract N00014-85-C-0020.
LA: English
ER: M (Marine)
AB: A large fraction of dissolved organic matter (DOM) in seawater is composed of biologically refractory substances. The authors propose to examine organic acid photo-production in seawater as a tool to evaluate the importance of photofragmentation of biologically refractory organic matter in the sea. Laboratory studies will be integrated with a sea-going program, SOLARS, to establish a broad data base for the spatial and temporal distribution of organic acids in coastal and oceanic waters.
AN: 2203631

                                                                   1352 of 1521  
TI: Biogeochemical cycling of organic matter in acidic environments: Are microbial degradative processes adapted to low pH?.
AU: Benner,-R.; Lewis,-D.L.; Hodson,-R.E.
CA: Environmental Protection Agency, Athens, GA (USA). Environmental Research Lab.
SO: ECOL.-RES.-SER.-U.S.-ENVIRON.-PROT.-AGENCY. 1987. 25 pp
NT: NTIS Order No.: PB87-195392/GAR. Prepared with Georgia Univ., Athens.
RN: EPA/600/D-87/176 (EPA600D87176)
LA: English
ER: F (Freshwater)
AB: The rates of microbial degradation of a variety of dissolved and particulate substrates in water and sediment from the Okefenokee Swamp, Georgia, and Corkscrew Swamp, Florida, are compared. The relationship between pH and rates of biodegradation or organic substrates was determined for natural microbial assemblages and for several bacterial isolates from these environments. Results suggest that microbial degradative processes that rely on extracellular enzymes are depressed at low pHs, whereas the microbial utilization of low-molecular-weight compounds that can be directly transported into cells is not substantially affected by variations in pH from 4 to 8.
AN: 2203310

                                                                   1353 of 1521  
TI: VERTEX: Phytoplankton/iron studies in the Gulf of Alaska.
AU: Martin,-J.H.; Gordon,-R.M.; Fitzwater,-S.; Broenkow,-W.W.
AF: Moss Landing Mar. Lab., Moss Landing, CA 95039, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 5A, pp. 649-680
LA: English
ER: M (Marine)
AB: VERTEX studies were performed in the Gulf of Alaska in order to test the hypothesis that iron deficiency was responsible for the phytoplankton's failure to remove major plant nutrients from these waters. In view of the observed Fe distributions and the results of phytoplankton Fe enrichment experiments, it was concluded that Gulf of Alaska atmospheric Fe input rates are sufficient to support moderately high rates of primary productivity; however, not enough Fe is available to support the high growth rates that would lead to normal major nutrient depletion. Enhanced Fe input does occur along the Alaska continental margin, where normal NO sub(3) surface depletion is observed. Coccolithophorids appear to be best able to cope with low Fe conditions; however, they cannot compete with diatoms when Fe is readily available.
AN: 2190336

                                                                   1354 of 1521  
TI: Seasonal oxygen cycles and biological new production in surface waters of the subarctic Pacific Ocean.
AU: Emerson,-S.
AF: Sch. Oceanogr., Univ. Washington, Seattle, WA 98195, USA
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1987. vol. 92, no. C6, pp. 6535-6544
LA: English
ER: M (Marine)
AB: Seasonal cycles of oxygen, temperature and salinity at Ocean Weather Station P in the subarctic Pacific Ocean reveal a regular 4-6% supersaturation of oxygen in the surface waters during the summers of the 10-year period 1969-1978. The main processes causing supersaturation are surface water heating and the net effect of primary production and community respiration. The biological and heating signals are separated using a mixed layer model and estimates for the air-water gas exchange rate speed. Biological new production during the summer (mid-May to mid-August) is estimated to be 100-300 mg C m super(-2)/d.
AN: 2190168

                                                                   1355 of 1521  
TI: Detrital processing in seagrass systems: A review of factors affecting decay rates, remineralization and detritivory.
AU: Harrison,-P.G.
AF: Dep. Bot., Univ. British Columbia, Vancouver, B.C. V6T 2B1, Canada
SO: AQUAT.-BOT. 1989. vol. 35, no. 3-4, pp. 263-288
LA: English
ER: M (Marine)
AB: The literature on three related aspects of the ecological role of seagrass detritus was analysed for clues to the factors that determine the rates of decomposition, the amount of remineralization vs. immobilization of nitrogen and the nutritional value of the detritus to animals. Rates of decomposition (usually < 1% of dry wt./day) are generally low compared with other vascular macrophyte sources of detritus, but are influenced by many variables, e.g., chemical composition and growth state of the plant when decay begins, pre-treatments given the plant material (drying, grinding), methods of incubating (litterbags, enclosed microcosms), and the physical and chemical environment in which decay occurs. Standard techniques are lacking, making comparisons difficult.
AN: 2190166

                                                                   1356 of 1521  
TI: Nitrogen isotope fractionation by oceanic zooplankton.
AU: Checkley,-D.M.,Jr.; Miller,-C.A.
AF: Dep. Mar., Earth, and Atmos. Sci., Box 8208, North Carolina State Univ., Raleigh, NC 27695-8208, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 10, pp. 1449-1456
LA: English
ER: M (Marine)
AB: The ratio of  super(15)N: super(14)N for particulate matter suspended in oceanic, surface waters is high after recent nitrate depletion and low in the stable, oligotrophic ocean. We hypothesize that zooplankters and other pelagic heterotrophs produce  super(15)N-depleted ammonium and  super(15)N-enriched particulate matter that are, respectively, recycled in and exported from the euphotic zone and thus cause the low values of  super(15)N: super(14)N in oligotrophic seas. Heretofore, this pattern was attributed to nitrogen-fixation by the phytoplankton. We measured the ratio of  super(15)N: super(14)N in the bodies and excreted ammonium of zooplankters from the northwest Pacific Ocean and compared these values to the ratio of  super(15)N: super(14)N for subeuphotic, dissolved nitrate.
AN: 2190147

                                                                   1357 of 1521  
TI: Phytoplankton, nutrients, and turbidity in the Chesapeake, Delaware, and Hudson estuaries.
AU: Fisher,-T.R.; Harding,-L.W.,Jr.; Stanley,-D.W.; Ward,-L.G.
AF: Univ. Maryland-CEES, Horn Point Environ. Lab., Cambridge, MD 21613, USA
SO: ESTUAR.-COAST.-SHELF-SCI. 1988. vol. 27, no. 1, pp. 61-93
LA: English
ER: M (Marine)
AB: Estuaries receive continuous inputs of nutrients from their freshwater sources; but the fate of the inputs is poorly known. Chesapeake and Delaware Bays frequently show a turbidity maximum in the oligohaline region, a chlorophyll maximum in clearer waters seaward of the turbidity maximum, and a nutrient-depleted zone at the highest salinities. In the Hudson River estuary, mixing diagrams were dominated by lateral waste inputs from New York City, and nutrient removal could not be estimated. In Chesapeake Bay, there was consistent removal of total N, nitrate, phosphate, and silicate from the water column, whereas in Delaware Bay, total N, ammonium, total P, and phosphate were removed. Phytoplankton accumulation was associated with inorganic nutrient removal, suggesting that phytoplankton uptake was a major process responsible for nutrient removal.
AN: 2190068

                                                                   1358 of 1521  
TI: Production of biologically refractory dissolved organic carbon by natural seawater microbial populations.
AU: Brophy,-J.E.; Carlson,-D.J.
AF: Coll. Oceanogr., Oregon State Univ., Corvallis, OR 97331, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 4A, pp. 497-507
LA: English
ER: M (Marine)
AB: Carbon from glucose and leucine added at natural concentrations to seawater was biologically transformed to higher molecular weight (mol. wt) dissolved materials that persisted through 6 months of incubation. At the end of incubation, the amount of carbon in high mol. wt dissolved fractions was approximately equal to the amount of carbon incorporated into particulate fractions. In tests of their resistance to biological utilization, only 1-17% of the high mol. wt materials were respirated when re-incubated with seawater microbial populations, whereas 40-75% of the monomers were respired over the same time span. In situ transformations of biologically available carbon may be an important source of refractory dissolved organic carbon in the oceans.
AN: 2189884

                                                                   1359 of 1521  
TI: Nutrient fluxes during extended blooms of Arctic ice algae.
AU: Cota,-G.F.; Prinsenberg,-S.J.; Bennett,-E.B.; Loder,-J.W.; Lewis,-M.R.; Anning,-J.L.; Watson,-N.H.F.; Harris,-L.R.
AF: Dep. Fish. and Oceans, Mar. Ecol. Lab., Bedford Inst. Oceanogr., Dartmouth, N.S., Canada
SO: J.-GEOPHYS.-RES.-C-OCEANS. 1987. vol. 92, no. C2, pp. 1951-1962
LA: English
ER: M (Marine)
AB: Estimates of nutrient demand by dense mats of ice algae in the high Arctic indicate that substantial nutrient fluxes are necessary to satisfy the observed growth over the 2-month bloom. In our study area, Barrow Strait, the quantity of nutrients in the surface-mixed layer is about 3-10 times greater than estimates of total demand during the bloom, and nutrient fluxes in the water column are estimated to be of the same order of magnitude as algal demand. In the latter half of the bloom, when biomass levels are high, it appears that established populations of ice algae may experience cyclic conditions of nutrient limitation during neap tides when nutrient fluxes are minimal.
AN: 2187122

                                                                   1360 of 1521  
TI: Biological nitrogen fixation (acetylene reduction) associated with green algal (cyanobacterial) communities in the Beachwood Mangrove Nature Reserve. 1. The effect of environmental factors on acetylene reduction activity.
AU: Mann,-F.D.; Steinke,-T.D.
AF: Dep. Bot., Univ. Durban-Westville, Priv. Bag X54001, Durban 400, South Africa
SO: S.-AFR.-J.-BOT.-S.-AFR.-TYDSKR.-PLANTKD. 1989. vol. 55, no. 4, pp. 438-446
LA: English
AB: Nitrogen fixation of blue-green algae (cyanobacteria) associated with Avicennia marina  (Forssk.) Vierh. pneumatophores and wet and dry surface sediments was investigated in the Beachwood Mangrove Nature Reserve by means of the acetylene reduction technique. Studies revealed percentage moisture and temperature to be the prime factors influencing ARA (acetylene reduction activity) in these habitats and rates were highest under submerged conditions and at 22 degree C. High concentrations of inorganic nitrogen (between 1 and 5 mg/l) significantly depressed ARA in all habitats. Increases in ARA occurred with increase in light intensity up to 40  mu E m super(-2)/s, with negligible dark rates being recorded in association with the wet and dry surface sediments. Significant dark rates of ARA and stimulation of ARA by sucrose in association with the pneumatophores indicated that bacteria may also be contributing to ARA in this habitat. No organic carbon stimulation was noted in the other sites. Salinity had little effect on ARA over the range generally experienced in each habitat.
AN: 2183566

                                                                   1361 of 1521  
TI: Preliminary studies of fungi communities on Rhizophora mangle .
AU: Barreto,-M.B.; Bastardo,-H.; Bonilla,-A.
AF: Inst. Zool. Trop., Univ. Cent. Venezuela, PBO 47058 Caracas 1041-A, Venezuela
CA: Japanese Soc. for Marine Biotechnology, Tokyo (Japan)
Foundation for Advancement of International Science
ICSU Int. Scientific Comm. for Biotechnology
CO: 1. Int. Marine Biotechnology Conf. (IMBC '89), Tokyo (Japan), 4-6 Sep 1989
SO: PROGRAM-OF-THE-FIRST-INTERNATIONAL-MARINE-BIOTECHNOLOGY-CONFERENCE-IMBC-'-89. 1989. p. 79
NT: Summary only.
LA: English
ER: M (Marine)
AB: An important coastal zone in tropical and sub-tropical zones is dominated by mangrove forest. Its plays an important role in the productivity of detritus biomass of estuarine ecosystems. Recently there has been a great interest for the activity of fungi in the decomposition processes of mangrove roots from the point of view of the importance of these functional groups during the dynamics of mineralization of plant material from mangrove forest. Rhizophora mangle  and water samples were taken from Tacarigua Lagoon and cultivated in Petri dishes by spread method. Among the most abundant were Aspergillus  sp. and Penicillum  which represent 44% of the total population. The biochemical tests performed on the fungal community showed that the major percentage of fungi are able to degrade lignocellulose compounds and mineralize organic phosphorous and nitrogen.
AN: 2183477

                                                                   1362 of 1521  
TI: Cadmium movement and accumulation in a sediment-water-plant system.
AU: Peverly,-J.H.
AF: Dep. Agron., Cornell Univ., Ithaca, NY 14853, USA
CO: University of Missouri's 22. Annu. Conf. on Trace Substances in Environmental Health, St. Louis, MO (USA), 23-26 May 1988
SO: TRACE-SUBSTANCES-IN-ENVIRONMENTAL-HEALTH-22. Hemphill,-D.D.-ed. 1988. pp. 399-409
LA: English
ER: F (Freshwater)
AB: Studies in 1986 of cadmium (Cd) mobilization from dosed pond sediments after inputs stopped in 1983 indicated that Cd may be absorbed by rooted aquatic plants and thus returned to the aquatic food chain. The limits of this process were studied in 1987. Cd in plants, water, and sediments was determined and characterized in replicated, outdoor aquaria after single acute dosages. The aquaria were representative of the hardwater, non-flowing impoundments 1.1m deep used in 1986. Over 60 mgCd m super(-2) was absorbed from sediments by plants in the higher Cd treatments and accumulated in root and leaf tissues. Electron microscopy and x-ray analysis confirmed its presence in cell walls. This represented a considerable return of sediment Cd to the aquatic food chain.
AN: 2179692

                                                                   1363 of 1521  
TI: Cycling of methane, carbon monoxide, nitrous oxide, and hydroxylamine in a meromictic, coastal lagoon.
AU: Butler,-J.H.; Pequegnat,-J.E.; Gordon,-L.I.; Jones,-R.D.
AF: Coop. Inst. Res. Environ. Sci., Univ. Colorado/NOAA, Boulder, CO 80309, USA
SO: ESTUAR.-COAST.-SHELF-SCI. 1988. vol. 27, no. 2, pp. 181-203
LA: English
ER: B (Brackish)
AB: The vertical distributions of methane, carbon monoxide, nitrous oxide, and hydroxylamine were measured in a seasonally stratified, coastal lagoon in northern California. The production of gases was estimated from mass-balance calculations where possible, including considerations of diffusion and microbial oxidation. From late spring through most of the summer the lagoon remained oligotrophic, with biological activity concentrated near the pycnocline and the sediments.
AN: 2179189

                                                                   1364 of 1521  
TI: Spatial and temporal variability in south San Francisco Bay (USA). 2. Temporal changes in salinity, suspended sediments, and phytoplankton biomass and productivity over tidal time scales.
AU: Cloern,-J.E.; Powell,-T.M.; Huzzey,-L.M.
AF: U.S. Geol. Surv., MS 496, 345 Middlefield Rd., Menlo Park, CA 94025, USA
SO: ESTUAR.-COAST.-SHELF-SCI. 1989. vol. 28, no. 6, pp. 599-613
LA: English
ER: M (Marine); B (Brackish)
AB: Short-term variability of a conservative quantity (salinity) and two nonconservative quantities (chlorophyll a, suspended particulate matter) was measured across a sampling grid in the South San Francisco Bay estuary. Both chlorophyll a and SPM varied periodically with tidal stage (increasing on ebbing currents). For surface salinity, most (70-80%) of the observed intratidal variability was correlated with the tidal flux, both in the deep channel and over the lateral shoals. The short-term variability of SPM concentration was only weakly correlated with the advective flux, indicating that local sources of SPM (resuspension) are important. Hence, the magnitude and mechanisms of intratidal variability differ among constituents and among bathymetric regimes in this estuary.
AN: 2175002

                                                                   1365 of 1521  
TI: Periplatform carbonate flux in the northern Bahamas.
AU: Pilskaln,-C.H.; Neumann,-A.C.; Bane,-J.M.
AF: Monterey Bay Aquarium Res. Inst., Pacific Grove, CA 93950, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 9A, pp. 1391-1406
LA: English
ER: M (Marine)
AB: In a preliminary effort to quantify the off-bank transport and vertical flux of shallow-water carbonates, a sediment trap was moored at 500 m in Northwest Providence Channel, northern Bahamas. Two months of particulate flux data collected during a fair-weather, storm-free period revealed that the flux components differed significantly from that of the underlying sediments. The results suggest that the flux and deposition of bank-derived carbonates in the periplatform environment are variable on a temporal scale, where a relatively minor proportion of bank-derived components is deposited during calm, storm-free periods, with the balance delivered during the passage of frequent, low-amplitude seasonal storms and occasional hurricanes.
AN: 2174291

                                                                   1366 of 1521  
TI: Amelioration of storm-water quality by a freshwater estuary.
AU: Klarer,-D.M.; Millie,-D.F.
AF: Ohio Dep. Nat. Resour., Old Woman Creek State Nat. Preserve and Natl. Estuar. Res. Reserve, 2514 Cleveland Rd., East, Huron, OH 44839, USA
SO: ARCH.-HYDROBIOL. 1989. vol. 116, no. 3, pp. 375-389
NT: Incl. 38 ref.
LA: English
ER: F (Freshwater)
AB: The role of Old Woman Creek estuary, Lake Erie (U.S.A.) in ameliorating the quality of storm-water flow was investigated. Chemical parameters in water samples collected immediately following three distinct storm events displayed one of three patterns: 1) decreasing concentrations due to dilution by storm-water runoff, 2) increasing concentrations due to sediment input and/or surface runoff, and 3) increasing concentrations attributed to storm interflow. Outflow/inflow ratios of chemical concentrations indicated that up to 60% of the metals and up to 80% of the biologically-important nutrients were retained within the estuary. Amelioration of storm-water quality was attributed to sedimentation, biological uptake, and geochemical processes.
AN: 2169204

                                                                   1367 of 1521  
TI: In situ holographic imaging of settling particles: Applications for individual particle dynamics and oceanic flux measurements.
AU: Costello,-D.K.; Carder,-K.L.; Betzer,-P.R.; Young,-R.W.
AF: Dep. Mar. Sci., Univ. South Florida, 140 Seventh Ave. South, St. Petersburg, FL 33701, USA
SO: DEEP-SEA-RES.-A-OCEANOGR.-RES.-PAP.. 1989. vol. 36, no. 10, pp. 1595-1605
LA: English
ER: M (Marine)
AB: A new dual-axis holographic imaging system provides a means for estimating in situ the sizes, shapes, settling rates and densities of both individual particles and aggregates. The optical system utilizes two independent imaging systems with HeNe laser illumination to record holographically the particles moving through the collection cup from two orthogonal perspectives. Four free-drifting, holographically equipped sediment traps have been utilized on three cruises to the North Pacific Ocean. The holographically determined dynamic densities for individual particles include high-density material of eolian origin and also lower density organic material. Such optically enhanced sediment traps provide a means of directly recording particle settling dynamics and may also provide insight into biological activity within sediment traps.
AN: 2164315

                                                                   1368 of 1521  
TI: Geochemical characteristics of transformation of inorganic sulfur in the Black Sea water column.
OT: Geokhimicheskie osobennosti transformatsii neorganicheskikh form sery v tolshche vod Chernogo morya
AU: Sovga,-E.E.; Eremeev,-L.V.; Solov'-eva,-L.V.
AF: Mor. Gidrofiz. Inst. AN Ukrainian SSR, Sevastopol', Ukrainian SSR, USSR
SO: GEOKHIMIYA. 1989. no. 11, pp. 1648-1655
LA: Russian
ER: M (Marine)
AB: Based on the results of surveys made during the 44th cruise of the R/V Mikhail Lomonosov  a scheme was constructed showing S transformations as a result of chemical and microbiological processes. Areas are revealed of active S reduction and intense oxidation of H sub(2)S in the zone of coexistence of O sub(2) and H sub(2)S and in the off-bottom layer. Microbiological mechanism of molecular S occurrence in the water column in considered in detail.
AN: 2163720

                                                                   1369 of 1521  
TI: Microbiological and biogeochemical processes in the oceanic water column as indicators of hydrothermal activity.
OT: Mikrobiologicheskie i biogeokhimicheskie protsessy v vodnoj tolshche okeana kak pokazateli aktivnosti podvodnykh gidroterm
AU: Gal'-chenko,-V.F.; Ivanov,-M.V.; Lein,-A.Yu.
AF: Inst. Mikrobiol. AN SSSR, Moscow, USSR
SO: GEOKHIMIYA. 1989. no. 8, pp. 1075-1088
LA: Russian
ER: M (Marine)
AB: An approximate method is described aimed at detecting hydrothermal spring from board the vessel based on dark fixation of 14CO sub(2) and CH sub(4) oxidation using 14C isotope and bacterial counts. The abundance of bacteria was by 1-2 orders higher in near-bottom waters above hydrothermal fields and the microbial activity was by 2-4 orders higher than in the rest of the water column. Anomalous abundance of specific groups of bacteria was in good agreement with anomalous physicochemical parameters (Eh, optical density) and anomalously high content of dissolved Mn. An operating model is considered of a hydrothermal plume which is differentiated by CH sub(4) oxidation and CO sub(2) fixation.
AN: 2163697

                                                                   1370 of 1521  
TI: Strategic marine research -- new Sea Grant initiative.
AU: Attaway,-D.H.
AF: Natl. Sea Grant Coll. Program, NOAA, Rockville, MD 20852, USA
SO: SEA-TECHNOL. 1989. vol. 30, no. 7, pp. 33-34
LA: English
ER: M (Marine)
AB: The term "global change" is used increasingly to describe the basis of a unified scientific effort. Cooperative efforts among several agencies led to two interagency reports, the U.S. Global Ocean Science Program (USGOSP) and Our Changing Planet: A U.S. Strategy for Global Change Research. These reports represent the first stage of coordinated efforts in strategic planning by federal agencies. The National Sea Grant College Program has an essential role to play in these programs. This role corresponds with its meeting needs in strategic research called for recently in Public Law 100-220, particularly in three major areas identified. These are: 1) Biogeochemical dynamics; 2) Global ecosystems and productivity processes; and 3) Coastal margins and polar ocean processes.
AN: 2158432

                                                                   1371 of 1521  
TI: Temporal changes in interstitial water chemistry and calcite recrystallization in marine sediments.
AU: Delaney,-M.L.
AF: Inst. Mar. Sci., Univ. California, Santa Cruz, CA 95064, USA
SO: EARTH-PLANET.-SCI.-LETT. 1989. vol. 95, no. 1-2, pp. 23-37
LA: English
ER: M (Marine)
AB: Recrystallization processes in marine sediments can alter the extent to which biogenic calcite composition serves as a proxy of oceanic chemical and isotopic history. Realistic, albeit simplified, models of the temporal evolution of interstitial water profiles of Ca, Mg, and Sr were used with several patterns of recrystallization rate variation to predict the composition of recrystallized inorganic calcite. Comparison of predictions with measured Mg/Ca and Sr/Ca ratios in severely altered calcite samples from several Deep Sea Drilling Project sites demonstrates that models incorporating temporal variation in interstitial water composition more successfully predict observed calcite compositions than do models which rely solely on present-day interstitial water chemistry.
AN: 2154287

                                                                   1372 of 1521  
TI: The dynamic greenhouse: Feedback processes that may influence future concentrations of atmospheric trace gases and climatic change.
AU: Lashof,-D.A.
AF: U.S. Environ. Prot. Agency, Washington, DC 20460, USA
SO: CLIM.-CHANGE. 1989. vol. 14, no. 3, pp. 213-242
LA: English
ER: M (Marine)
AB: The sensitivity of the climate system to anthropogenic perturbations over the next century will be determined by a combination of feedbacks that amplify or damp the direct radiative effects of increasing concentrations of greenhouse gases. A number of important geophysical climate feedbacks, such as changes in water vapor, clouds, and sea ice albedo, are included in current climate models, but biogeochemical feedbacks such as changes in methane emissions, ocean CO sub(2) uptake, and vegetation albedo are generally neglected. The relative importance of a wide range of feedbacks is assessed here by estimating the gain associated with each individual process. While each of these feedbacks is modest compared to the water vapor feedback, the biogeochemical feedbacks in combination have the potential to substantially increase the climate change associated with any given initial forcing.
AN: 2143944

                                                                   1373 of 1521  
TI: Anaerobic degradation of betaine by marine Desulfobacterium  strains.
AU: Heijthuijsen,-J.H.F.G.; Hansen,-T.A.
AF: Dep. Microbiol., Univ. Groningen, Kerklaan 30, NL-9751 NN Haren, Netherlands
SO: ARCH.-MICROBIOL. 1989. vol. 152, no. 4, pp. 393-396
LA: English
ER: M (Marine)
AB: From enrichment cultures with betaine (20 mM) and sulfate (20 mM) as the substrates and intertidal mud as an inoculum, a betaine-oxidizing, sulfate-reducing bacterium (strain PM4) was isolated. Strain PM4 was an oval to rod-shaped, Gram-negative, motile bacterium, which was able to oxidize lactate completely to CO sub(2) and contained, during growth on betaine and sulfate, high activities of key enzymes of the acetyl CoA/CO dehydrogenase pathway (carbon monoxide dehydrogenase and formate dehydrogenase), but not of 2-oxo-glutarate dehydrogenase, a key enzyme of the citric acid cycle. On the basis of its morphological and physiological characteristics, strain PM4 was identified as a Desulfobacterium) strain. Desulfobacterium  PM4 grew on betaine with a doubling time of approximately 20 h at 30 degree C and produced N, N-dimethylglycine (in a 1:1 ratio) and sulfide as products. In this type of betaine metabolism one of the methyl groups of betaine is oxidized to CO sub(2) and the reducing equivalents general are used for the reduction of sulfate.
AN: 2143299

                                                                   1374 of 1521  
TI: Sterols in ocean sediments: Novel tracers to examine habitats of cetaceans, pinnipeds, penguins and humans.
AU: Venkatesan,-M.I.; Santiago,-C.A.
AF: Inst. Geophys. and Planet. Phys., Univ. California, Los Angeles, CA 90024, USA
SO: MAR.-BIOL. 1989. vol. 102, no. 4, pp. 431-437
NT: 34 ref.
LA: English
ER: M (Marine)
AB: The role of marine mammals in the biogeochemical flux of oceanic carbon is largely unknown. Capillary gas chromatography and gas chromatography/mass spectrometry after organic solvent extraction and compound class separation of feces from cetaceans (toothed and baleen whales), pinnipeds and penguins (collected in 1987 from Monterey Bay, off the coast of California or from Sea World, San Diego, California, USA) indicate that the unusual sterol profile in the Antarctic sediments, with epicoprostanol predominating over its isomer, coprostanol, originates from baleen whales (blue and fin whales). The sterol distribution in feces from baleen whales is different from that of other animals studied here and also from anthropogenic sewage (collected in 1987 from wastewater outfalls off the coast of southern California, USA).
AN: 2141232

                                                                   1375 of 1521  
TI: Seasonal changes in the silicon cycle within a Gulf Stream warm-core ring.
AU: Brzezinski,-M.A.; Nelson,-D.M.
AF: Dep. Biol. Sci., Univ. California, Santa Barbara, CA 93106, USA
SO: DEEP-SEA-RES. 1989. vol. 36, no. 7A, pp. 1009-1030
LA: English
ER: M (Marine)
AB: The silicon cycle within Gulf Stream warm-core ring 82-B was examined before and after spring stratification using silicon isotope tracers. In April, prior to stratification, the ring was isothermal and isohaline to 400 m. Ambient silici acid concentrations were ca 3  mu mol/l and biogenic silica concentrations ranged from 80 to 100 nmol/l throughout this depth range. By June, a seasonal pycnocline had developed and silicic acid concentrations were depleted to  less than or equal to  0.2  mu mol/l in the upper 20-30 m. Vertically integrated particulate silica concentrations in the upper 80 m had increased four-fold compared to those for the upper 110 m in April/May. Siliceous biomass was concentrated in the upper 40 m, with a subsurface maximum of ca 1000 nmol Si/l within the seasonal pycnocline. The upper 80 m remained a zone of net silica production, but net dissolution was occurring at all depths > 100 m.
AN: 2139364

                                                                   1376 of 1521  
TI: A peat fire in the Okavango Delta, Botswana, and its importance as an ecosystem process.
AU: Ellery,-W.N.; Ellery,-K.; McCarthy,-T.S.; Cairncross,-B.; Oelofse,-R.
AF: Dep. Bot., Univ. Witwatersrand, PO Wits, Johannesburg 2050, South Africa
SO: AFR.-J.-ECOL. 1989. vol. 27, no. 1, pp. 7-21
LA: English
ER: F (Freshwater)
AB: The progressive abandonment and desiccation of the lower Nqoga River system and its associated vegetation-covered peat deposits, has resulted in the development of subsurface peat fires. These appear to have been burning within the study area for decades and consist of a mosaic of burning fronts, the first of which burns to a depth of up to 15 cm. This relatively shallow fire destroys the bases of stems and plant rhizomes, thereby preventing re-establishment of the former plant community by vegetative growth. The depths to which these burn are limited by peat moisture content or by the presence of an incombustible inorganic substrate. The initial collapse is some 30-40 vol.%. Further compaction is brought about by rainfall and animal trampling which may cause volume reductions of as much as 98%.
AN: 2139353

                                                                   1377 of 1521  
TI: Litter production and turnover of the mangrove Kandelia candel  (L.) Druce in a Hong Kong tidal shrimp pond.
AU: Lee,-S.Y.
AF: Dep. Zool., Univ. Hong Kong, Pokfulam Rd., Hong Kong
SO: ESTUAR.-COAST.-SHELF-SCI. 1989. vol. 29, no. 1, pp. 75-87
LA: English
ER: M (Marine)
AB: Production and turnover of Kandelia candel  litter were studied for 2 years in a tidal shrimp pond (10 ha) at the Mai Po Marshes, northwest Hong Kong. Stand characteristics of average tree height and dbh were good predictors of litter production while climatic variables, especially rainfall, could be used to predict the production of various litter components. Residence times were related to both inundation frequency and crab (Chiromanthes  spp.) consumption. As the Kandelia candel  stands were located largely above mean water level, there was little export of litter. The litter produced was predominantly decomposed or consumed by macrofauna in situ, creating a large energy sink which was not coupled to pelagic secondary production. The significance of these findings are discussed in relation to the fishery production and wildlife conservation value of the marshes.
AN: 2139313

                                                                   1378 of 1521  
TI: Palaeoclimate analysis of  super(2)H/ super(1)H ratios in peat sequences with variable plant composition.
AU: Dupont,-L.M.; Mook,-W.G.
AF: Inst. Palynol. und Quartaerwiss., Univ. Goettingen, Wilhelm-Weber-Str. 2, D-3400 Goettingen, FRG
SO: CHEM.-GEOL.-ISOT.-GEOSCI.-SECT. 1987. vol. 7, no. 3-4, pp. 323-333
LA: English
ER: F (Freshwater)
AB: Under equal climatic conditions the deuterium content of plants varies with species. The deuterium content of peat cellulose, therefore, is related to the plant composition. This dependence is calculated for each taxon in specific peat sequences by means of multiple linear regression, and subtracted from the deuterium content of the cellulose fraction of each sample. The residual variation should contain a climatic effect such as the climatic temperature dependence of  super(2)H/ super(1)H in precipitation, which is to be correlated with other palaeotemperature records.
AN: 2138763

                                                                   1379 of 1521  
TI: Early incorporation of polysulphides in sedimentary organic matter.
AU: Kohnen,-M.E.L.; Sinninghe-Damste,-J.S.; ten-Haven,-H.L.; de-Leeuw,-J.W.
AF: Org. Geochem. Unit, Fac. Chem. Technol. and Mater. Sci., Delft Univ. Technol., de Vries van Heystplantsoen 2, NL-2628 RZ Delft, Netherlands
SO: NATURE. 1989. vol. 341, no. 6243, pp. 640-641
LA: English
ER: M (Marine)
AB: The increase in sulphur content of organic matter with depth in Recent sediments has been attributed to incorporation of either H sub(2)S or polysulphides or to a combination of both. Here the authors report the identification of homologous series of cyclic disulphides with a linear carbon skeleton and of a cyclic di- and trisulphide with a C sub(20) isoprenoid carbon skeleton in sediments of Quaternary to Pliocene age. Although incorporation of H sub(2)S can still explain the presence of cyclic disulphides, the cyclic trisulphide implies incorporation of inorganic polysulphides in sedimentary organic matter at the earliest stages of diagenesis.
AN: 2138325

                                                                   1380 of 1521  
TI: Sedimentary sulfides in the nearshore Georgia Bight.
AU: Fallon,-R.D.
AF: E.I. Du Pont Co., Haskell Lab. Toxicol. and Ind. Med., Elkton Rd., Newark, DE 19711, USA
SO: ESTUAR.-COAST.-SHELF-SCI. 1987. vol. 25, no. 6, pp. 607-619
LA: English
ER: M (Marine)
AB: Sedimentary sulfide, iron, and organic matter were measured in neritic sediments from the Georgia Bight. The two measured depth integrated sulfur pools, FeS + HS super(-) and FeS sub(2), tended to decrease with increasing distance from shore out to 33 km. Total iron and organic matter were strongly correlated and both tended to decrease with increasing distance from shore. Sediment depth profiles of organic matter/reduced sulfur suggest relatively constant rates of sulfate reduction over the top 40 cm of sediment. Differences in within-station variance indicated regions of lower and higher spatial/temporal heterogeneity, that may be related to tidally driven circulation patterns. No seasonal cycles were evident in sedimentary sulfides.
AN: 2135623

                                                                   1381 of 1521  
TI: Decomposition and the annual flux of detritus from fallen timber in tropical mangrove forests.
AU: Robertson,-A.I.; Daniel,-P.A.
AF: Australian Inst. Mar. Sci., PMB No. 3, Townsville MC, Qld. 4810, Australia
SO: LIMNOL.-OCEANOGR. 1989. vol. 34, no. 3, pp. 640-646
LA: English
ER: M (Marine)
AB: Single exponential decay models fitted to dry mass and carbon decomposition data for tree trunks in mixed Rhizophora  mangrove forests in tropical Australia had decay constants of 0.083 and 0.108/yr respectively. Decay of twigs and small branches was more rapid with decay constants of 0.276 (dry mass) and 0.310/yr (carbon). Aboveground standing stocks of dead wood components in young and mature forests were (g C m super(-2)): trunks, 15.3 and 221.9; prop roots, 5.7 and 86.8; branches, 3.5 and 32.2; twigs, 3.2 and 3.1.
AN: 2134628

                                                                   1382 of 1521  
TI: Microbiological processes in bottom sediments of the Kraternaya Bay.
OT: Mikrobiologicheskie protsessy v donnykh osadkakh bukhty Kraternoj
AU: Namsaraev,-B.B.; Karnachuk,-O.V.; Borzenkov,-I.A.; Starynin,-D.A.
AF: Inst. Mikrobiol. AN SSSR, Moscow, USSR
SO: BIOL.-MORYA-MAR.-BIOL.,-VLADIVOST. 1989. no. 3, pp. 52-58
LA: Russian
ER: M (Marine)
AB: A study was made of microbiological processes of synthesis and destruction of the organic matter in bottom sediments of the Kraternaya Bay (the Kuril Islands). High concentrations of bacteria and algae (algobacterial mats) were observed in the areas of gas and hydrothermal vents. The rate of organic matter synthesis in algobacterial mats varied from 2,343 to 5,940 mgC/l of wet sediment per day. Photosynthesis yielded only 112-740 mgC/l/day. In silt sediments of the Bay the rate of organic matter synthesis was by 2-3 orders of magnitude lower. High rates of microbic destruction of albumen and cellulose especially in algobacterial mats were recorded. Estimation of rates of organic matter destruction at terminal stages revealed that the bulk of organic matter is expended during sulphate reduction with the leading role of methanogenesis.
AN: 2132089

                                                                   1383 of 1521  
TI: Scientific research and management of coastal environments. The critical path approach to the notion of assimilation capacity.
OT: Recherche scientifique et gestion de l'environnement marin. Critique de la notion de capacite d'assimilation
AU: Marin,-J.-M.
AF: Inst. Biogeochim. Mar., Ec. Norm. Super., 1 Rue Maurice-Arnoux, 92120 Montrouge, France
CA: Ministere de l'Environnement, Paris (France). Com. Scientifique Milieu Marin
CO: Devenir des Polluants Chimiques en Milieu Marin, Brest (France), 26-27 Jan 1988
SO: FATE-OF-CHEMICAL-POLLUTANTS-IN-THE-MARINE-ENVIRONMENT:-SEMINAR-OF-THE-SCIENTIFIC-COMMITTEE-"MARINE-ENVIRONMENT"-OF-THE-ENVIRONMENT-MINISTRY,-BREST,-26-27-JAN-1988.  DEVENIR-DES-POLLUANTS-CHIMIQUES-EN-MILIEU-MARIN:-SEMINAIRE-DU-COMITE-SCIENTIFIQUE-"MILIEU-MARIN",-MINISTERE-L'-ENVIRONNEMENT,-BREST,-26-27-JAN-1988. 1988. vol. 14, no. 6 pp. 751-762
ST: OCEANIS-DOC.-OCEANOGR.. vol. 14, no. 6
LA: French
ER: M (Marine)
AB: A "Critical Path Approach" (C.P.A.) to the notion of "Assimilation Capacity" (A.C.) is presented. Apart from the terminological problems involved and the political and socio-economic difficulties encountered when defining the assimilation capacity, other practical problems are discussed. This is an interesting procedure from the scientific point of view, although difficult to apply to a coastal environment, for the biogeochemical cycle and the long-term fate of numerous pollutants are still insufficiently known.
AN: 2126672

                                                                   1384 of 1521  
TI: Chemical cycling in Washington's coastal zone.
AU: Carpenter,-R.; Peterson,-M.L.
AF: Sch. Oceanogr., Univ. Washington, Seattle, WA 98195, USA
SO: COASTAL-OCEANOGRAPHY-OF-WASHINGTON-AND-OREGON. Landry,-M.R.;Hickey,-B.M.-eds. 1989. vol. 47 pp. 367-510
ST: ELSEVIER-OCEANOGR.-SER. vol. 47
LA: English
ER: M (Marine)
AB: Studies since the early 1970s have focused on chemicals which are of concern due to their persistence and relatively toxic natures, such as the Pu isotopes,  super(210)Po,  super(210)Pb, As, Hg and polynuclear aromatic hydrocarbons. Major improvements in sample collection, preparation and analytical chemistry capabilities have been made for determinations of trace organic compounds, stable metals and their speciation and radionuclides in environmental samples. Most of these improvements have been exploited in studies of chemical cycling off the Washington coast and are described in greater detail throughout this chapter. This chapter will review developments in our understanding of the biogeochemical cycling of primarily these toxic and persistent compounds.
AN: 2119135

                                                                   1385 of 1521  
TI: Flux and recycling of bioactive substances in the surface sediments of the deep basins off southern California: Progress report, November 1987-July 1988.
AU: Jahnke,-R.A.
CA: Skidaway Inst. of Oceanography, Savannah, GA (USA)
SO: REP.-U.S.-DEP.-ENERGY. 1989. 4 pp
NT: NTIS Order No.: DE88014251/GAR.
RN: DOE/ER/60627-1 (DOEER606271)
LA: English
ER: M (Marine)
AB: Goals of this project are to develop an understanding of the processes responsible for the recycling of biogenic debris in the surface sediments of Santa Monica Basin and to quantitatively determine the rate at which dissolved chemicals exchange across the sediment-bottom water boundary. This information will provide fundamental information about organic matter decomposition and oxidation at the seafloor as well as provide a quantitative minimum estimate of the lateral input of organic matter to the deep basin from the adjacent continental shelf. We developed a preliminary organic carbon budget for the seafloor based on pore water and in situ benthic chamber flux measurements. The latter were performed with the MANOP Bottom Lander free-vehicle which was developed during the NSF sponsored Manganese Nodule Program. (Contract FG09-88ER60627. Portions of this document are illegible in microfiche products.)
AN: 2117664

                                                                   1386 of 1521  
TI: A geochemical perspective on the causes and periodicity of mass extinctions.
AU: Moses,-C.O.
AF: Dep. Geol. Sci., Lehigh Univ., Bethlehem, PA 18015, USA
SO: ECOLOGY. 1989. vol. 70, no. 4, pp. 812-823
LA: English
ER: M (Marine)
AB: Environmental change, including changes in biogeochemical cycles, climate, and sea level, is the primary cause of extinctions that result from mechanisms external to evolutionary dynamics. Evidence that extraordinary tectonism, including volcanism, seafloor spreading, and eustatic sea level changes, took place prior to and at the Cretaceous-Tertiary boundary (K-TB) is sufficient to account for the environmental changes that led to mass extinctions. A coincident impact of an extraterrestrial object cannot be conclusively ruled out. Some mineralogic evidence suggests a scenario that includes impacts, but this does not rule out tectonism. The K-TB is certainly the best studied and most often discussed extinction boundary, but study of other extinction episodes and other potential extinction causes will now shed more light on mechanisms than continued study of the K-TB.
AN: 2106433

                                                                   1387 of 1521  
TI: (Radioecology of freshwater biosystems.).
OT: Radioehkologiya presnovodnykh biosystem
AU: Kulikov,-N.V.; Chebotina,-M.Ya.
SO: SVERDLOVSK-USSR-URO-AN-S.S.S.R. 1988. 129 pp
NT: Incl. bibliogr.: 194 ref.
LA: Russian
ER: F (Freshwater)
AB: The monograph summarizes the results of long-term studies on behaviour of various radionuclides in water-hydrobionts and water-ground model systems as dependent on concentration of isotopic and non-isotopic carriers, pH, light, temperature and season of the year. Effect of ionizing radiation on freshwater organisms and communities is discussed with reference to external sources and ambient radioactive contamination.
AN: 2098760

                                                                   1388 of 1521  
TI: Non-steady-state biological removal of atmospheric particles from Mediterranean surface waters.
AU: Buat-Menard,-P.; Davies,-J.; Remoudaki,-E.; Miquel,-J.C.; Bergametti,-G.; Lambert,-C.E.; Ezat,-U.; Quetel,-C.; La-Rosa,-J.; Fowler,-S.W.
AF: Cent. Faibles Radioact., Lab. Mixte CNRS-CEA, Domaine CNRS, F-91198 Gif sur Yvette Cedex, France
SO: NATURE. 1989. vol. 340, no. 6229, pp. 131-134
LA: English
ER: M (Marine)
AB: Here the authors report data from time-series measurements of both atmospheric inputs and water-column particulate fluxes at 200 m depth obtained from sediment traps, which show that such a biological control also prevails in northwestern Mediterranean waters. On short time-scales, concentrations and fluxes in the upper water column can increase significantly following dust transport and deposition events, with a response time of the order of one week. Such non-steady-state behaviour must be taken into account when assessing the impact of pulsed atmospheric inputs on particulate trace element concentrations and fluxes in the water column.
AN: 2089209

                                                                   1389 of 1521  
TI: Numerical models for predicting watershed acidification.
AU: Eary,-L.E.; Jenne,-E.A.; Vail,-L.W.; Girvin,-D.C.
AF: Battelle, Pac. Northwest Lab., Environ. Sci. Dep., P.O. Box 999, Richland, WA 99352, USA
SO: ARCH.-ENVIRON.-CONTAM.-TOXICOL. 1989. vol. 18, no. 1-2, pp. 29-53
NT: Special issue: Acid rain.
LA: English
ER: F (Freshwater)
AB: Three numerical models of watershed acidification, including the MAGIC II, ETD, and ILWAS models, are reviewed, and a comparative study is made of the specific process formulations that are incorporated in the models to represent hydrological, geochemical, and biogeochemical processes which affect the responses of watersheds to acidic deposition. The models have been used to simulate the short-term dynamics of water quality at a number of different watersheds currently receiving acidic deposition.
AN: 2081027

                                                                   1390 of 1521  
TI: Oxygen consumption and nutrient regeneration ratios along isopycnal horizons in the Pacific Ocean.
AU: Boulahdid,-M.; Minster,-J.F.
AF: GRGS/UM 39, 18 Ave. Edouard Belin, 31055 Toulouse Cedex, France
SO: MAR.-CHEM. 1989. vol. 26, no. 2, pp. 133-153
LA: English
ER: M (Marine)
AB: The P/N/-O sub(2) Redfield ratios were re-estimated from variations of the dissolved concentrations along five isopycnal surfaces of the Pacific Ocean, using the Geosecs data. Nutrients in the South Pacific shallow waters can be explained by mixing of two end-members and regeneration. Very high Redfield ratios are found (P/N/-O sub(2) = 1/20.1/195). In the tropical areas, a similar model would give more classical values of P/N/-O sub(2) = 1/15.4/165. This difference can either be owing to diapycnal mixing or to the fact that phosphates are not limiting production in this area.
AN: 2078096

                                                                   1391 of 1521  
TI: Some organic components in the sediments of Hooghly Estuary.
AU: Ghosh,-P.B.; Choudhury,-A.
AF: Dep. Mar. Sci., Univ. Calcutta, Calcutta 700019, India
SO: ENVIRON.-ECOL. 1989. vol. 7, no. 2, pp. 395-397
LA: English
ER: M (Marine); B (Brackish)
AB: Organic carbon, hydrocarbon, fatty acid, sterol and terpene content in the sediments of Hooghly Estuary covering three stations were studied. All the components showed some seasonal variation in concentration. Organic carbon, fatty acid and hydrocarbon were high in monsoon season at station 2 whereas sterol and terpene were comparatively high in postmonsoon season at all stations. The variations of organic carbon and fatty acid were directly correlation with the texture of the sediments while hydrocarbon, sterol and terpene were not.
AN: 2076899

                                                                   1392 of 1521  
TI: Aerosol transport of polynuclear aromatic hydrocarbons over the Mediterranean Sea.
AU: Grimalt,-J.; Albaiges,-J.; Sicre,-M.A.; Marty,-J.C.; Saliot,-A.
AF: Dep. Environ. Chem., CID-CSIC, E-08034 Barcelona, Spain
SO: NATURWISSENSCHAFTEN. 1988. vol. 75, no. 1, pp. 39-42
LA: English
ER: M (Marine)
AB: The occurrence of polynuclear aromatic hydrocarbons (PAH) in open marine areas is usually attributed to atmospheric inputs. However, at present, almost no data exist on the PAH composition in marine aerosols, representing an important lack of knowledge for the understanding of the biogeochemical cycle of these hydrocarbons. The authors present a study on the composition of PAH in particle-size aerosols collected over the open sea (Western Mediterranean) showing for first time the importance of their atmospheric deposition fluxes. The results are also discussed in terms of air mass trajectories, organic sources, and particle size association.
AN: 2073689

                                                                   1393 of 1521  
TI: Investigating the fate of dyes in the environment.
AU: Baughman,-G.L.; Perenich,-T.A.
CA: Environmental Protection Agency, Athens, GA (USA). Environmental Research Lab.
SO: ECOL.-RES.-SER.-U.S.-ENVIRON.-PROT.-AGENCY. 1988. 11 pp
NT: NTIS Order No.: PB88-184619/GAR.
RN: EPA/600/D-88/050 (EPA600D88050)
LA: English
AB: The rationale and approach that underlie the use of mathematical models to forecast the environmental behavior of organic chemicals are examined. The general concepts are then used to show how knowledge of environmental and dye chemistry can be used to suggest pathways that are likely or unlikely to be determinants of dye fate in aquatic systems. The uncharged dyes are considered in regard to possible volatilization, sorption, and bioconcentration. Suitable kinetic and equilibrium constants are not currently available for quantitative prediction using mathematical models.
AN: 2064547

                                                                   1394 of 1521  
TI: Microbial and animal processing of detritus in a woodland stream.
AU: Petersen,-R.C.,Jr.; Cummins,-K.W.; Ward,-G.M.
AF: Stream and Benthic Ecol. Group, Dep. Ecol. and Limnol., Univ. Lund, Box 65, 22100 Lund, Sweden
SO: ECOL.-MONOGR. 1989. vol. 59, no. 1, pp. 21-39
LA: English
ER: F (Freshwater)
AB: The detritus standing crop, microbial respiration, and macroinvertebrate biomass were examined in monthly samples from the riffle sections of a first-order woodland stream. Total detritus was remarkably constant. Decreases in standing crop were attributable to microbial respiration, macroinvertebrate assimilation, and downstream export. Microbial respiration annually removed 150% of the average standing crop, with the major effect on the smallest particle size category. Macroinvertebrate assimilation, defined as the sum of respiration and growth, removed 11.6% of the detritus standing crop annually. Shredders accounted for 20% of total animal assimilation, with the remaining 80% attributable to collectors and grazers.
AN: 2062009

                                                                   1395 of 1521  
TI: Indicative parameters of denitrification in river sediments.
AU: Muela,-A.; Gorostiza,-I.; Iriberri,-J.; Egea,-L.
AF: Dep. Microbiol., Fac. Cienc., Univ. Pais Vasco, Apdo. 644, E-48080 Bilbao, Spain
SO: ACTA-HYDROCHIM.-HYDROBIOL. 1988. vol. 16, no. 2, pp. 157-163
LA: English
ER: F (Freshwater)
AB: Denitrification is studied in sediments from two areas of the River Butron, Spain, which represent different situations with respect to their degree of pollution. In all the samples analysed denitrification follows a kinetic type Michaelis-Menten with respect to nitrate. V sub(max), K sub(m) and number of denitrifiers are clearly superior in the polluted are when compared to the cleaner area, indicating an advantage given that denitrification suggests an alternative pathway for breaking down organic matter with low levels of dissolved oxygen. By comparison between K sub(m) and natural nitrate concentration values we find that v follows a first order kinetic depending directly on the nitrate concentration. v also presents higher values in the area of the river where the entry of sewage is taking place than in the cleaner area.
AN: 2061943

                                                                   1396 of 1521  
TI: Nitrogen biogeochemistry in an unpolluted estuary: The importance of benthic denitrification.
AU: Seitzinger,-S.P.
AF: Patrick Cent. Environ. Res., Acad. Nat. Sci., Philadelphia, PA 19103, USA
SO: MAR.-ECOL.-PROG.-SER.. 1987. vol. 41, no. 2, pp. 177-186
NT: Incl. 45 ref.
LA: English
ER: B (Brackish)
AB: Denitrification rates (N sub(2) production), and benthic ammonium, nitrate and oxygen fluxes were measured along a salinity gradient in Ochlockonee Bay (Florida, USA) over an annual cycle. The major source of NO sub(3)@)u- or NO sub(2)@)u- for denitrification is from nitrification in the sediments not diffusion of NO sub(3)@)u- or NO sub(2)@)u- from the overlying water. Denitrification is a major removal mechanism for nitrogen in Ochlockonee Bay, and removes, on an annual basis, an amount of nitrogen equivalent to 54% of the river input of dissolved inorganic nitrogen. N sub(2)O fluxes were small compared to N sub(2) fluxes; N sub(2)O/N sub(2) ratios in March were less than 0.01.
AN: 2060966

                                                                   1397 of 1521  
TI: Regional distribution and geobiochemical significance of concentration patterns of non-volatile organochlorine compounds in dabs (Limanda limanda ) of the southern and central North Sea.
OT: Regionale Verteilung und geobiochemische Bedeutung der Konzentrationsmuster schwerfluechtiger Organochlorverbindungen in Klieschen (Limanda limanda ) der suedlichen und zentralen Nordsee
AU: Buether,-H.
AF: Bundesforschungsanst. Fisch., Inst. Kuesten- und Binnenfisch., Aussenstelle Cuxhaven, Niedersachsenstr., D-2190 Cuxhaven, FRG
CA: Bremen Univ. (FRG). Fachber. Biologie/Chemie
SO: VEROEFF.-INST.-KUEST.-BINNENFISCH. 1988. no. 99, 237 pp
NT: Bibliogr.: 282 ref. Diss. (Dr. rer. nat.).
LA: German
ER: M (Marine)
AB: Regional distribution and geobiochemical significance of concentration patterns of non-volatile organochlorine compounds in dabs (Limanda limanda ) of the southern and central North Sea. In December 1984, January and May 1985 and January 1986 at a total of 109 stations in the German Bight and the southern and central North Sea dabs Limanda limanda  were caught for an investigation of the regional distribution of chlorinated organic compounds such as PCBs,  Sigma DDT, HCB,  alpha -HCH and lindane. For comparison the contamination of cod (Gadus morhua ), plaice (Pleuronectes platessa ), flounder (Platichthys flesus ) and blue mussels (Mytilus edulis ) was determined.
AN: 2054119

                                                                   1398 of 1521  
TI: RRS Discovery  Cruise 175, 18 June-15 July 1988. Investigations of the flux of biogeochemical material and its transformation by the midwater biota at the BIOTRANS (c. 47 degree N, 20 degree W).
AU: Pugh,-P.R.
AF: Inst. Oceanogr. Sci., Deacon Lab., Wormley, Godalming, Surrey GU8 5UB, UK
SO: CRUISE-REP.-INST.-OCEANOGR.-SCI.,-DEACON-LAB. 1988. no. 204, 72 pp
LA: English
ER: M (Marine)
AB: Discovery cruise 175 can be considered as a prelude to and test run for parts of the BOFS (Biogeochemical Ocean Flux Studies) sampling programme. It encompassed a multidisciplinary approach to investigation of the flux of biogeochemical material and its transformation by the midwater biota. The BIOTRANS site (ca. 47 degree N, 20 degree W) was chosen as it will be one of the primary sampling site during the BOFS experiment. Attempts were made to assess a) the sedimentation rates of particles using sediment traps; b) the vertical distribution of particles (8-256  mu m), using the in situ particle counting system FIDO; c) the vertical distribution and diel migrations of plankton and micronekton; d) the vertical distribution (0-300 m) of bacteria, phytoplankton and their pigments, and nutrients in conjunction with measurements of the physical structure of the water column; e) flagellate grazing potential.
AN: 2054076

                                                                   1399 of 1521  
TI: Biogeochemical cycling of organic carbon in the sediments of the Grote Rug reservoir.
AU: Adams,-D.D.; Eck,-G.T.M.-Van
AF: Cent. Earth and Environ. Sci., State Univ. New York, Plattsburgh, NY 12901, USA
CO: 3. International Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Ecosystems, Utrecht (Netherlands), 18 Aug 1986
SO: PROCEEDINGS-OF-THE-THIRD-INTERNATIONAL-WORKSHOP-ON-THE-MEASUREMENT-OF-MICROBIAL-ACTIVITIES-IN-THE-CARBON-CYCLE-IN-AQUATIC-ECOSYSTEMS. Cappenberg,-T.E.;Steenbergen,-C.L.M.-eds. 1988. no. 31 pp. 319-330
ST: ERGEB.-LIMNOL.-ADV.-LIMNOL. no. 31
LA: English
ER: F (Freshwater)
AB: In situ measurements of electron acceptors were utilized to construct an organic carbon decomposition budget for the upper 30 cm of sediments in the "Grote Rug", an oligotrophic freshwater reservoir near Dordrecht, the Netherlands. From the 80 g/m super(2)/y total organic carbon deposited to the sediments, 60% was decomposed aerobically with the remainder fueling anaerobic metabolism (15%) or being permanently buried (25%). The major anaerobic processes accounting for carbon mineralization were sulfate reduction and methanogenesis, in approximate equal proportions. Denitrification was not important to carbon recycling.
AN: 2051160

                                                                   1400 of 1521  
TI: The biogeochemistry of molecular hydrogen in sulfate-reducing sediments.
AU: Novelli,-P.C.
CA: State Univ. of New York, Stony Brook (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1988. vol. 49, no. 6, 253 pp
NT: Diss. Ph.D.: Order No.: DA8812798.
LA: English
AB: Concentrations of molecular hydrogen (H sub(2)) have been measured using an equilibration-vacuum transfer method coupled to mercuric oxide reduction. In hemipelagic sediments (Eastern Tropical North Pacific) and bioturbated sediments (Princess Louisa Inlet, BC, and Buzzards Bay, MA) hydrogen levels were lowest in surface sediments and increased with depth. Experiments using sulfate-reducing sediments have shown that hydrogen oxidation can be coupled to nitrate reduction. Apparent hydrogen production rates were determined in laboratory incubations of sediments amended with inhibitors of sulfate reduction and methanogenesis. The results show that hydrogen production is, in part, a function of the type of organic matter being degraded.
AN: 2050685

                                                                   1401 of 1521  
TI: The early diagenesis of transition metals in nearshore sediments.
AU: Shaw,-T.J.
CA: California Univ., San Diego (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1988. vol. 49, no. 6, 180 pp
NT: Diss. Ph.D.: Order No.: DA8811867.
LA: English
ER: M (Marine)
AB: Transition metal concentrations in sediments can be used to predict the environment of deposition at the time of burial. In order to understand the relationship between environmental conditions and metal burial this study identifies factors important in the transport and burial of metals during the sediment early diagenesis. Sediment cores from five different depositional environments in the Southern California Borderland were studied. Evidence is presented which suggests that at least some detrital nickel, copper, chromium, molybdenum, and vanadium is associated with biogenic material. A model which predicts oxygen consumption as a function of organic carbon input was applied to the most oxic cores.
AN: 2050682

                                                                   1402 of 1521  
TI: Metabolism of methylated sulfur compounds in anoxic salt marsh sediments.
AU: Kiene,-R.P.
CA: State Univ. of New York, Stony Brook (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1987. vol. 48, no. 2, 269 pp
NT: Diss. Ph.D.: Order No.: FAD DA8710926.
LA: English
ER: B (Brackish)
AB: The microbial metabolism of methylated reduced sulfur compounds was examined in anoxic salt marsh sediments. Methionine and dimethyl-sulfoniopropionate (DMSP) were identified as potential precursors of volatile organic sulfur compounds. Microbial hydrolysis of sulfur-carbon linkages resulted in the liberation of methane thiol (MSH) and dimethyl sulfide (DMS) from methionine and DMSP respectively. Ultimately, methylated sulfur compounds were consumed by biological processes and converted to mineralized end products such as CO sub(2), CH sub(4) and H sub(2)S. The metabolism of methylated sulfur compounds in sediments may reduce the emissions of these volatile compounds to the water column and the atmosphere.
AN: 2047034

                                                                   1403 of 1521  
TI: Mechanisms controlling silica flux from sediments and implications for the biogeochemical cycling of silica in Lake Michigan.
AU: Conley,-D.J.
CA: Michigan Univ., Ann Arbor (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1987. vol. 48, no. 2, 113 pp
NT: Diss. Ph.D.: Order No.: FAD DA8712089.
LA: English
ER: F (Freshwater)
AB: Mechanisms governing the benthic regeneration of biogenic silica (BSi) in Lake Michigan were investigated. The impact of sediment fluxes of dissolved silica (Si) and soluble reactive phosphorus (SRP) on the biogeochemical cycling of Si and phosphorus were examined. Si fluxes measured directly by incubation of intact sediment cores were 1 to 10 times greater than Si fluxes calculated from pore water Si concentration gradients. Manipulation experiments confirmed the importance of a surface flocculent layer to measured Si fluxes. Differences in turnover rates of Si and P calculated for Lake Michigan provide the mechanism for the rapid Si depletion previously documented in the Great Lakes.
AN: 2046044

                                                                   1404 of 1521  
TI: Biogeochemical processes of incorporation and transformation of  super(14)C labelled fulvic acid, humic acid and simple organic molecules at the sediment-water interface (submarine canyon of the NW Mediterranean).
AU: Buscail,-R.; Gadel,-F.
AF: Lab. Sedimentol. et Geochim. Mar., Univ. Perpignan, France
CO: 3. Int. Meet. of the International Humic Substances Society, Oslo (Norway), 4-8 Aug 1986
SO: ADVANCES-IN-HUMIC-SUBSTANCES-RESEARCH. Becher,-G.-ed. 1987. vol. 62 pp. 409-412
ST: SCI.-TOTAL-ENVIRON. vol. 62
LA: English
ER: M (Marine)
AB: The input of organic compounds at the marine water-sediment interface was simulated by the injection of 14C labelled raygrass fulvic and humic acids and glutamic acid in the overlying water of three identically preserved interfaces. After incubations of 6 days under in situ conditions (13 degree  C, oxidizing conditions), separation of the resulting products are carried out by successive chemical extractions. They correspond to the relative importance of biological (respiration, assimilation) and geochemical (condensation in geopolymers and adsorption) processes. Two experiments have showed predominance of biological processes (with  super(14)C fulvic and glutamic acids), while in the case of  super(14)C humic acid, incorporation in sediment and geochemical processes are more important.
AN: 2043142

                                                                   1405 of 1521  
TI: Inorganic and organic ligand binding of lead and cadmium and resultant implications for bioavailability.
AU: Campbell,-J.H.; Evans,-R.D.
CO: 3. Int. Meet. of the International Humic Substances Society, Oslo (Norway), 4-8 Aug 1986
SO: ADVANCES-IN-HUMIC-SUBSTANCES-RESEARCH. Becher,-G.-ed. 1987. vol. 62 pp. 219-226
ST: SCI.-TOTAL-ENVIRON. vol. 62
LA: English
ER: F (Freshwater)
AN: 2043077

                                                                   1406 of 1521  
TI: Biogeochemistry of organic matter deposition and diagenesis in Bering-Chukchi and Gulf of Mexico sediments.
AU: Caughey,-M.E.
CA: Texas Univ., Austin (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1988. vol. 49, no. 6, 162 pp
NT: Diss.: Ph.D. Order No.: DA8816418.
LA: English
ER: M (Marine)
AB: The research described focused on two biogeochemical processes: (1) the formation of  super(13)C-depleted carbonates in sediments influenced by natural, submarine hydrocarbon seepage, and (2) the distribution, deposition and early diagenesis of marine and terrigenous organic matter in continental shelf sediments from a sub-arctic and a sub-tropical environment. Analyses of suites of sediment grab samples from the continental shelves of the eastern Bering and Chukchi Seas and the northwestern Gulf of Mexico provide insights into patterns of organic matter distribution in shallow marine environments.
AN: 2040317

                                                                   1407 of 1521  
TI: The distribution and molecular characterization of dissolved DNA in aquatic environments.
AU: DeFlaun,-M.F.
CA: South Florida Univ., Tampa (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1988. vol. 49, no. 6, 144 pp
NT: Diss. Ph.D.: Order No.: DA8806187.
LA: English
AB: The distribution of dissolved DNA in oceanic, estuarine and freshwater environments in southwest Florida and the Gulf of Mexico was determined. Oceanic concentrations of extracellular DNA ranged from 0.2 to 19  mu g/l. Estuarine concentrations, followed the seasonal trend in water temperature. Diel studies indicated little variation in dissolved DNA concentrations in offshore environments, while variations in the estuary were significant, with maximum concentrations in nighttime samples. These results indicated that dissolved DNA is in a size range sufficient to contain gene sequences, which may be important in natural transformation of microbial populations.
AN: 2040263

                                                                   1408 of 1521  
TI: Carbon flow in an agricultural stream ecosystem.
AU: Robertson,-T.E.
CA: Iowa State Univ., Ames (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1988. vol. 49, no. 2, 165 pp
NT: Diss. Ph.D.: Order No.: DA8805133.
LA: English
ER: F (Freshwater)
AB: The ecological structure and functioning of agriculturally impacted streams, as relates to carbon dynamics, as well as the functional relationships of the invertebrate community to their food source, is unknown. The purpose of this study at Big Creek, Iowa, was to quantify the annual flow of carbon through its various compartments and to relate these carbon sources to the structuring of the invertebrate community in this second order, agriculturally impacted stream. Dissolved organic matter (fraction < 0.45 u) is the dominant fraction, by weight, in the study section. Of the daily terrestrial production of 48,528 kg C day super(-1), 4% or 1851 kg C day super(-1) is allochthonous inputs to upper Big Creek of which 99% is transported out of the upper section.
AN: 2034267

                                                                   1409 of 1521  
TI: Recent biogenic sedimentation on the Antarctic continental margin.
AU: Leventer,-A.R.
CA: Rice Univ., Houston, TX (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1989. vol. 49, no. 10, 249 pp
NT: Diss. Ph.D.: Order No.: DA8900255.
LA: English
ER: M (Marine)
AB: Floral and geochemical analyses were conducted on sinking and suspended particulate matter, and on sea ice and recent sediment samples from the northwestern Weddell Sea--northern Antarctic Peninsula area, and McMurdo Sound, in the southwestern Ross Sea. Data from McMurdo Sound reveal that although large numbers of diatom frustules dissolve within the upper water column the decrease in silica mass flux is much smaller. At mid-water depths, increases in the absolute flux of Nitzschia curta  and Thalassiosira  spp. indicate the influence of lateral advection. Within a near-bottom nepheloid layer additional dissolution occurs. Dilution and preferential dissolution is responsible for production of a surface sediment assemblage dominated by Thalassiosira  spp. and Nitzschia curta .
AN: 2034219

                                                                   1410 of 1521  
TI: Fluxes of particulate protein amino acids in Funka Bay in autumn.
AU: Yanada,-M.; Maita,-Y.
AF: Lab. Mar. Chem., Fac. Fish., Hokkaido Univ., Hakodate, Japan
SO: BULL.-FAC.-FISH.-HOKKAIDO-UNIV. 1986. vol. 37, no. 2, pp. 134-143
LA: Japanese
ER: M (Marine)
AB: The fluxes of particulate protein amino acids were examined in three size fractions (> 690  mu m, 350 similar to 690  mu m, and < 350  mu m) of sinking particles in a sediment trap deployed at a depth of 74 m in Funka Bay from August to October. The total flux of amino acids for this period was 135 mg/m super(-2)/day. The fluxes of the amino acids in the three size fractions accounted for 50, 30 and 20% of the total flux, respectively. In the coastal area, the organic materials excreted by zooplankton (e.g. fecal materials and larvacea houses) transported more than 80% of the protein amino acids into the trap at the depth of 74 m. The amino acid content in the three size fractions increased with larger sinking particles.
AN: 2033917

                                                                   1411 of 1521  
TI: Cadmium-113m as a biogeochemical tracer for cadmium in Lake Michigan.
AU: Dunn,-D.L.
CA: Clemson Univ., SC (USA)
SO: DISS.-ABST.-INT.-PT.-B-SCI.-and-ENG. 1988. vol. 49, no. 5, 133 pp
NT: Diss. Ph.D.: Order No.: DA8816265.
LA: English
ER: F (Freshwater)
AB: Cadmium is a toxic trace metal responsible for several debilitating pathological conditions. Antropogenic activity has greatly enhanced environmental cadmium mobility. There has been concern about the fate of cadmium in potable water supplies. The Great Lakes are major sources of freshwater for much of the populated United States and Canada. The Lake Michigan watershed has been sampled for  super(113m)Cd. This long-lived metastable isotope of cadmium allowed independent evaluation of cadmium distribution in this dynamic ecosystem.  super(113m)Cd analysis was not hampered by contamination or loss. The  super(113m)Cd activities confirm the expected semiconservative behavior for cadmium.
AN: 2033703

                                                                   1412 of 1521  
TI: Trace metal studies on the starfish Asterias rubens  L. from the Western Baltic Sea.
AU: Bruegmann,-L.; Lange,-D.
AF: Acad. Sci. GDR, Inst. Mar. Res., Rostock-Warnemuende, GDR
SO: CHEM.-ECOL. 1988. vol. 3, no. 4, pp. 295-311
LA: English
ER: M (Marine)
AB: In 1984, 115 samples of the starfish Asterias rubens  L. collected in the south-eastern part of Cadet Trench (Mecklenburg Bay/Western Baltic Sea) were analyzed for their contents of a few major (calcium, magnesium) and trace elements (cadmium, copper, iron, mercury, manganese, nickel, lead, selenium and zinc). Distinct differences were found between starfish from different stations, and these are attributed to the composition of the sediments acting as a substrate for their prey (mussels, snails). Except for cadmium, the concentrations of the elements studied all correlated negatively with the diameter and weight of the starfish.
AN: 2030490

                                                                   1413 of 1521  
TI: Mobilization of radiocaesium in pore water of lake sediments.
AU: Comans,-R.N.J.; Middelburg,-J.J.; Zonderhuis,-J.; Woittiez,-J.R.W.; De-Lange,-G.J.; Das,-H.A.; Van-Der-Weijden,-C.H.
AF: Dep. Chem. and Mater. Sci., Netherlands Energy Res. Found. (ECN), P.O. Box 1, 1755 ZG Petten, Netherlands
SO: NATURE. 1989. vol. 339, no. 6223, pp. 367-369
LA: English
ER: F (Freshwater)
AB: The deposition of large amounts of radiocaesium from nuclear weapons testing and from accidents such as Chernobyl has necessitated study of the fate of these long-lived radioisotopes in the natural environment. Radiocaesium can be removed from the water column in lake systems by setting particles and surface sediments. This process reduces its mobility and the risk of assimilation by biota. Nevertheless, there are indications that radiocaesium may be mobilized from lacustrine anoxic sediments. The pore-water data indicate that radiocaesium is returned to the water column and thus becomes available for uptake by aquatic organisms.
AN: 2027012

                                                                   1414 of 1521  
TI: Particulate matter and nutrient distributions in the ice-edge zone of the Weddell Sea: Relationship to hydrography during late summer.
AU: Nelson,-D.M.; Smith,-W.O.,Jr.; Muench,-R.D.; Gordon,-L.I.; Sullivan,-C.W.; Husby,-D.W.
AF: Coll. Oceanogr., Oregon State Univ., Corvallis, OR 97331, USA
SO: DEEP-SEA-RES. 1989. vol. 36, no. 2A, pp. 191-209
LA: English
ER: M (Marine)
AB: Previous estimates of the marginal ice zone's quantitative contribution to biogeochemical cycles and annual productivity in the Southern Ocean may be conservative because of assumptions that phytoplankton blooms are associated only with actively retreating ice edges. Observations during March 1986, near an almost stationary ice edge in the northwestern Weddell Sea, revealed very low geostrophic currents, no appreciable horizontal gradients in temperature or salinity and no significant net melting or freezing in the ice-edge region. In contrast with previous observations in marginal ice zones, the distribution of phytoplankton biomass showed little correlation with the meltwater field; here, significant horizontal biomass gradients occurred in an area where vertical stability was almost uniform laterally and both elevated biomass and diminished nutrient levels extended well below the pycnocline.
AN: 2020833

                                                                   1415 of 1521  
TI: The effect of biological and physical disturbances on the transport of arsenic from contaminated estuarine sediments.
AU: Riedel,-G.F.; Sanders,-J.G.; Osman,-R.W.
AF: Acad. Nat. Sci., Benedict Estuarine Res. Lab., Benedict, MD 20612, USA
SO: ESTUAR.-COAST.-SHELF-SCI. 1987. vol. 25, no. 6, pp. 693-706
LA: English
ER: M (Marine); B (Brackish)
AB: From the distribution of dissolved and solid arsenic species in a contaminated estuarine sediment (Chesapeake Bay) and measured rates of flux of the various arsenic species the authors propose an empirical model for the cycling of arsenic between sediments and water column. The chemical form of arsenic in the sediment was largely determined by the redox state of the sediment. Arsenite was the dominant dissolved and solid species in the deeper reduced sediment, and arsenate was dominant in the oxidized surface layer. Nereis succinea , a burrowing polychaete, affected distribution and flux of arsenic from the sediments by its production of irrigated burrows. Although physical resuspension can produce large pulses of materials from contaminated sediments, continuous biological activity is likely to be more important in the mobilization of contaminants from sediments in many estuarine environments.
AN: 2010770

                                                                   1416 of 1521  
TI: On the biogeochemical characteristics of surface sediments in Chinhae Bay in September 1983.
AU: Yang,-D.B.; Hong,-J.S.
AF: Korea Ocean Res. Dev. Inst., Ansan, P.O. Box 29, Seoul 425-600, Korea
SO: BULL.-KOREAN-FISH.-SOC. 1988. vol. 21, no. 4, pp. 195-205
LA: English
ER: M (Marine)
AB: Distribution of organic materials in the surface sediments was investigated in September 1983 in Chinhae Bay system. Bottom waters containing less than lml/l of dissolved oxygen were found in Masan Bay, and in part of Kohyonsong Bay and Wonmunpo Bay. Organic carbon content in the surface sediments of Masan Bay was about 25 mg/g and it decreased with increasing distance from the inner Masan Bay. Mean organic carbon contents in Wonmumpo Bay and Kohyonsong Bay were 26.48 and 31.39 mg/g, respectively, which are higher values than those in Masan Bay where large amount of domestic and industrial wastewaters are discharged into the surface water and extensive phytoplankton bloom occurs almost year round. Mean organic nitrogen and pheophytin contents were also the highest in Kohyonsong Bay.
AN: 1993555

                                                                   1417 of 1521  
TI: Comparison of torbanites of various origins and evolutionary stages. Bacterial contribution to their formation. Cause of the lack of botryococcane in bitumens.
AU: Derenne,-S.; Largeau,-C.; Casadevall,-E.; Connan,-J.
AF: Lab. Chim. Bioorg. et Org. Phys., UA CNRS 456, E.N.S.C.P., 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France
SO: ORG.-GEOCHEM. 1988. vol. 12, no. 1, pp. 43-59
LA: English
ER: M (Marine)
AB: Torbanites are kerogen-rich deposits chiefly composed of the remains of a colonial alga with a morphology similar to the one of extant Botryococcus braunii . The structure of a torbanite within the oil window (BJ 248) was examined by FTIR and solid state  super(13)C NMR on bitumen-free, unheated material and pyrolysis residues, with identification of the hydrocarbons and fatty acids released on 400 degree C pyrolysis. Maturation entails a partial oxygen elimination, an extensive aromatization, a relative increase in tertiary aliphatic carbons and an important release of hydrocarbon chains. The absence of botryococcane in the bitumen of the twelve torbanites examined may reflect, either a complete removal of botryococcane precursors under partly oxic conditions of sedimentation, or, in some bitumens, a primary property linked to torbanite formation from the A race. Non-occurrence of botryococcane in crude oils cannot be used as a definite proof of the lack of Botryococcus  contribution in source rocks.
AN: 1992509

                                                                   1418 of 1521  
TI: Cadmium and mercury in coastal waters: Biogeochemistry and the use of Mytilus  as a quantitative indicator.
OT: Le cadmium et le mercure en milieu cotier: Biogeochimie et utilisation du genre Mytilus  comme indicateur quantitatif
AU: Cossa,-D.
CA: Univ. Paris-6 (France)
SO: PARIS-FRANCE-UNIVERSITE-PIERRE-ET-MARIE-CURIE 1987. 383 pp
NT: Thesis (Sciences).
LA: French
ER: M (Marine)
AB: Calcium and mercury are two elements whose biogeochemical behaviour is still poorly understood. The present work is intended to contribute to the knowledge of the behavior and the fluxes of these two metals in a coastal area -- the Estuary and Gulf of St. Lawrence. Contamination monitoring by optimizing the use of Mytilus  spp. as a tool is suggested. The work is therefore divided into two parts. The first is concerned with the biogeochemical aspect, the second considers the use of the genus Mytilus  as a quantitative biological indicator.
AN: 1991037

                                                                   1419 of 1521  
TI: Analytical models of lake phosphorus dynamics.
AU: Havis,-R.N.
AF: USDA-Agric. Res. Serv., Univ. Missouri, Columbia, MO 65201, USA
CA: North American Lake Management Soc., Arlington, VA (USA)
CO: 8. Annual International Symposium on Lake and Watershed Management, St. Louis, MO (USA), 15-18 Nov 1988
SO: 8.-ANNUAL-INTERNATIONAL-SYMPOSIUM-ON-LAKE-AND-WATERSHED-MANAGEMENT. 1988. p. 48
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: Lake trophic state can often be related to lake water phosphorus concentration. Accordingly, steady state models such as Vollenweider's P loading versus mean depth criterion axes are useful for prediction of steady trophic state conditions. This paper presents analytical mathematical models that consider lake bottom P cycling to predict the dynamic response of lake water P concentration in completely mixed systems to changes in external P loading. An exact solution to the lake model used annual average variables to simulate the recovery of a small lake in western Massachusetts. Simplified solutions were found using approximation techniques. Simulations from the approximate and exact models corresponded well, using variable values typical for the case study lake. Further model testing showed differences in predictions that were explained by the assumptions used to derive the approximate models.
AN: 1985698

                                                                   1420 of 1521  
TI: (Aquatic biology. Methods and techniques.).
OT: Biologie des eaux. Methodes et techniques
AU: Champiat,-D.; Larpent,-J.-P.
AF: Cent. Natl. Mach. Agric., Genie Rural Eaux For., 69000 Lyon, France
SO: PARIS-FRANCE-MASSON 1988. 374 pp
LA: French
ER: F (Freshwater)
AB: This book consists of two parts: one theoretical and the other practical. The first part deals with brackishwater organisms and biogeochemical cycling of major elements (C, N, Fe, Mn, P, S), pollution by sewage effluents, aerobic and anaerobic water purification (activated sludge or methanization). The authors study indicator bacteria, parasitology and disinfection problems. The second part is a technical data set for teaching and laboratory purposes.
AN: 1985306

                                                                   1421 of 1521  
TI: Anoxygenic phototrophic bacteria and sulfate-reducing bacteria in coastal lagoons.
OT: Role des bacteries phototrophes et des bacteries sulfato-reductrices dans les milieux lagunaires
AU: Caumette,-P.
CA: Aix-Marseille 3 Univ. (France)
SO: ETUD.-THESES-INST.-FR.-RECH.-SCI.-DEV.-COOP. PARIS-FRANCE-ORSTOM 1988. 304 pp
NT: Thesis (Sciences Naturelles).
LA: French
ER: B (Brackish)
AB: The occurrence and development of phototrophic bacteria and sulfate reducing bacteria, their role in the sulfur cycle and their biomass production is discussed. The study area is located in shallow and stratified lagoons in temperate regions (Mediterranean and Atlantic French coast) and Tropical regions "Atlantic coast of Ivory Coast in West Africa). Systematics of phototrophic bacteria, methods of physical, chemical and bacteriological analysis, and trophic relations between phototrophic bacteria and copepods are also described.
AN: 1985023

                                                                   1422 of 1521  
TI: The significance of malathion on the phosphorus dynamics of an acid bog lake.
AU: Jones,-K.L.
AF: Dep. Biol. Sci., Kent State Univ., Kent, OH 44242, USA
CO: 97. Annu. Meet. Ohio Acad. of Sci., Newark, OH (USA), 29 Apr 1988
SO: 97th-ANNUAL-MEETING:-THE-OHIO-ACADEMY-OF-SCIENCE.-APRIL-29-30,-MAY-1,-1988. Meserve,-L.-ed. 1988. vol. 88, no. 2 pp. 46-47
ST: OHIO-J.-SCI. vol. 88, no. 2
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: Phosphorus availability limits growth of zooplankton and phytoplankton in Triangle Lake, an acid bog located in Portage County, Ohio. This study examined the effects of malathion, an organophosphorus insecticide, on phosphate uptake by native microorganisms, and release rate of phosphate from dissolved organic phosphorus compounds (DOP), in surface waters of this lake. The results indicate that low concentrations of malathion, such as that which can be found in natural systems, may adversely affect phosphorus-limited aquatic communities.
AN: 1984049

                                                                   1423 of 1521  
TI: The dissolved organic phosphorus (DOP) composition of an acid bog lake in Portage County, OH.
AU: Edinger,-A.C.; Heath,-R.T.
AF: Dep. Biol. Sci., Kent State Univ., Kent, OH 44243, USA
CO: 97. Annu. Meet. Ohio Acad. of Sci., Newark, OH (USA), 29 Apr 1988
SO: 97th-ANNUAL-MEETING:-THE-OHIO-ACADEMY-OF-SCIENCE.-APRIL-29-30,-MAY-1,-1988. Meserve,-L.-ed. 1988. vol. 88, no. 2 p. 45
ST: OHIO-J.-SCI. vol. 88, no. 2
NT: Summary only.
LA: English
ER: F (Freshwater)
AB: The composition of the dissolved organic phosphorus (DOP) pool in surface water from Triangle Bog Lake, a glacial acid bog, was examined seasonally. The purpose of this work was to determine the composition of rapidly labelled DOP using radiometric procedures. Freshly collected 5 ml water samples, radiolabelled with carrier-free 32P orthophosphate and fractionated by Sephadex G-25, chromatographed as did orthophosphate in a control experiment. Radiolabelled water, both centrifuged (27,000 g for 15 minutes) and uncentrifuged, incubated for 24 hours at ambient temperature and run through the Sephadex column, indicated that the 32P orthophosphate was associated with high molecular weight compounds.
AN: 1983542

                                                                   1424 of 1521  
TI: Organic matter dynamics in four seasonally flooded forest communities of the Dismal Swamp.
AU: Megonigal,-J.P.; Day,-F.P.,Jr.
AF: Div. Wetlands Ecol., Savannah River Ecol. Lab., Drawer E, Aiken, SC 29801, USA
SO: AM.-J.-BOT. 1988. vol. 75, no. 9, pp. 1334-1343
LA: English
ER: F (Freshwater)
AB: Budgets of organic matter dynamics for plant communities of the Great Dismal Swamp were developed to summarize an extensive data base, determine patterns of biomass allocation, transfer and accumulation, and make comparisons with other forested wetlands. Aboveground net primary production on the flooded sites (1,050-1,176 g m super(-2)/yr) was significantly greater than on a rarely flooded site (831 g m super(-2)/yr). Estimates of belowground net primary production were comparable to aboveground production on flooded sites (824-1,221 gm super(-2)/yr). However, productivity was nearly three times greater belowground than aboveground on the rarely flooded site (2,256 g m super(-2)/yr). Aboveground productivity in Dismal Swamp forests is relatively high compared to other forested wetlands.
AN: 1980856

                                                                   1425 of 1521  
TI: A numerical scheme for solving a stream nutrient model.
AU: Hearne,-J.W.; Wake,-G.C.
AF: Dep. Math. and Stat., Massey Univ., Palmerston North, New Zealand
SO: APPL.-MATH.-MODEL. 1989. vol. 13, no. 3, pp. 155-159
LA: English
ER: F (Freshwater)
AB: Water quality models have often neglected to incorporate the feedback effects of nutrient uptake and release by riparian vegetation. When this increasingly important effect is incorporated, the numerical solution methods used for standard models are no longer applicable. Such a model comprises a coupled system of first-order nonlinear partial differential equations, the characteristics of which are different and (in one case) depend on the state variables. This paper provides a method of numerical solution which can be used by practitioners in this and other applications. An illustrative example is given.
AN: 1972345

                                                                   1426 of 1521  
TI: Biogeochemical cycling in the ocean. Part 1. Introduction to the effects of upwelling along the west coast of North America.
AU: Howe,-J.T.
CA: NASA, Moffett Field, CA (USA). Ames Research Cent
SO: NASA-TECH.-MEMO. 1986. 39 pp
NT: NTIS Order No.: N88-15349/9/GAR. NAS 1.15:88230, A-86181.
RN: NASA-TM-88230 (NASATM88230)
LA: English
ER: M (Marine)
AB: Coastal upwelling is examined as it relates to the cycling of chemical species in coastal waters along the west coast of North America. The temporal and spatial features of upwelling phenomena in a Eastern boundary regions of the North Pacific Ocean are presented and discussed in terms of upwelling episodes. Climate conditions affecting upwelling include: thermal effects, wind-induced shear stress which moves surface layers, and the curl of the wind stress vector which is thought to affect the extent and nature of upwelling and the formation of offshore convergent downwelling fronts. These effects and the interaction of sunlight and upwelled nutrients which result in a biological bloom in surface waters is modeled analytically. The roles of biological and chemical species, including the effects of predation, are discussed in that context, and relevant remote sensing and in situ observations are presented. Climatological, oceanographic, biological, physical, chemical events, and processes that pertain to biogeochemical cycling are presented and described.
AN: 1958918

                                                                   1427 of 1521  
TI: The excretion of phosphate and ammonia from microcrustaceans and its vertical and seasonal distribution at an offshore station in Lake Michigan.
AU: Busch,-J.L.; Brooks,-A.S.
AF: Cent. Great Lakes Stud., Univ. Wisconsin, 600 E. Greenfield Ave., Milwaukee, WI 53204, USA
CO: (23.) Congress in New Zealand, (Hamilton (New Zealand)), 8 Feb 1987
SO: CONGRESS-IN-NEW-ZEALAND-1987.-PROCEEDINGS. Sladecek,-V.-ed. 1988. vol. 23, no. 1 pp. 366-375
ST: VERH.-INT.-VER.-THEOR.-ANGEW.-LIMNOL.-PROC.-INT.-ASSOC.-THEOR.-APPL.-LIMNOL.-TRAV.-ASSOC.-INT.-LIMNOL.-THEOR.-APPL. vol. 23, no. 1
NT: Incl. 31 ref.
LA: English
ER: F (Freshwater)
AB: The zooplankton contribution of phosphate and ammonia in a Lake Michigan water column was estimated, vertical and temporal variation in this input was observed and the percentage contribution of this nutrient source was quantified. For discrete depths throughout the water column, the estimated contribution of zooplankton to the daily nutrient budget was less than 1 to 100% for PO sub(4) and 1 to 51% for NH sub(3). The results showed that throughout the season, the release of nutrients below the thermocline was insignificant. The highest percentages of nutrient excretion that were computed were for metalimnetic waters (10-15 m). There is evidence which indicates that zooplankton not only enhance nutrient availability at certain times of the year but that they also play a major role in determining the succession of algal species.
AN: 1957035

                                                                   1428 of 1521  
TI: Factors controlling the biogeochemical cycles of trace elements in fresh and coastal marine waters as revealed by artificial radioisotopes.
AU: Santschi,-P.H.
AF: Dep. Mar. Sci., Texas A&M Univ., Galveston, TX 77553-1675, USA
SO: LIMNOL.-OCEANOGR. 1988. vol. 33, no. 4, pt. 2, pp. 848-866
NT: Special issue: Comparative ecology of freshwater and marine ecosystems.
LA: English
ER: M (Marine); F (Freshwater)
AB: Radionuclides in aquatic ecosystems can provide important insights into the way physical, chemical, biological, and sedimentological processes are coupled into networks to control the transfer of major and trace elements within the waterbody itself and across its boundaries. Examples from artificial radionuclide studies in freshwater (Experimental Lakes Area in Northern Ontario, ELA) and coastal marine ecosystem enclosures (MERL tanks at Narragansett Bay, Rhode Island) show the cycling of selected trace elements across the sediment-water interface as these are influenced by various biogeochemical factors.
AN: 1951906

                                                                   1429 of 1521  
TI: Experimental studies of chemical stressors on whole lake ecosystems.
AU: Schindler,-D.W.
AF: Dep. Fish. and Oceans, Freshwater Inst., 501 University Crescent, Winnipeg, Man. R3T 2N6, Canada
CO: (23.) Congress in New Zealand, (Hamilton (New Zealand)), 8 Feb 1987
SO: CONGRESS-IN-NEW-ZEALAND-1987.-PROCEEDINGS. Sladecek,-V.-ed. 1988. vol. 23, no. 1 pp. 11-41
ST: VERH.-INT.-VER.-THEOR.-ANGEW.-LIMNOL.-PROC.-INT.-ASSOC.-THEOR.-APPL.-LIMNOL.-TRAV.-ASSOC.-INT.-LIMNOL.-THEOR.-APPL. vol. 23, no. 1
NT: Incl. 118 ref.
LA: English
ER: F (Freshwater)
AB: The earliest work at the Experiental Lakes Area (ELA) in Ontario, Canada in 1969, was a logical extension of earlier studies, focusing primarily the algal production associated with eutrophication. Over the years, the studies have broadened to include community changes, whole ecosystem processes and interactions of lakes with their watersheds and airsheds. Simple monitoring methods were used in the early experimental additions of nutrients and other chemicals to lakes. Lake 227, fertilized with N:P at 14:1 by weight, had produced algal blooms consisting primarily of chlorophytes, while Lake 226, with low rates of fertilization but an N:P ratio of 5:1, consistently produced blooms of nitrogen-fixing cyanophytes. In the mid-1970's the effect of acidification on the metabolism and nutrient cycles of Lake 223 was examined. Experiments on the changes in the biotic community, eutrophication, paleolimnological calibrations, biogeochemical cycles and some small scale and mesocosm experiments followed.
AN: 1948112

                                                                   1430 of 1521  
TI: Composition and bacterial utilization of free amino acids in tropical mangrove sediments.
AU: Stanley,-S.O.; Boto,-K.G.; Alongi,-D.M.; Gillan,-F.T.
AF: Dep. Sea Fish., 23 Old Wharf, Hobart, Tas. 7000, Australia
SO: MAR.-CHEM. 1987. vol. 22, no. 1, pp. 13-30
LA: English
ER: M (Marine)
AB: The composition and bacterial utilization of dissolved free amino acids in tropical mangrove sediments was examined. Amino acid concentrations and composition were similar to that of other organic-rich, anaerobic sediments with lowest and highest concentrations in the low and mid intertidal zones, respectively. The non-protein amino acid,  beta -glutamic acid, rarely reported in previous studies, was found as a major component of the interstitial pool. Intracellular amino acids from some cultured strains of sulphate-reducing bacteria showed the presence of  beta -glutamic acid as a major cellular constituent suggesting that these bacteria may be a source of this amino acid in mangrove pore waters. In high intertidal sediments, bacterial growth rates ( mu ) correlated significantly with total DFAA concentrations with depth. These experiments suggest that bacterial population in surface sediments are capable of utilizing all of the amino acid flux to the sediment-water interface in tropical mangroves.
AN: 1943979

                                                                   1431 of 1521  
TI: Dimethyl sulfide production during natural phytoplanktonic blooms.
AU: Nguyen,-B.C.; Belviso,-S.; Mihalopoulos,-N.; Gostan,-J.; Nival,-P.
AF: Cent. Faibles Radioact., Lab. Mixte CNRS-CEA, 91190 Gif-sur-Yvette, France
SO: MAR.-CHEM. 1988. vol. 24, no. 2, pp. 133-141
LA: English
ER: M (Marine)
AB: Dimethyl sulfide (DMS), produced by biological activity in seawater, is the principal gaseous form of sulfur released to the atmosphere by the ocean and plays an important part in the biogeochemical sulfur cycle. The production of DMS in seawater tanks has been quantified during phytoplankton bloom simulations for the growth and senescence phases of biomass. This gas production during the senescence phase is 7-26 times higher than during the growth phase. Thus, DMS production by the senescence process could be one of the major mechanisms for the generation of DMS in seawater.
AN: 1943174

                                                                   1432 of 1521  
TI: Preliminary estimations of the flow of certain trace metals in the oyster Crassostrea gigas  (Thunberg).
OT: Premieres estimations des flux de quelques elements metalliques chez l'huitre Crassostrea gigas  (Thunberg)
AU: Amiard,-J.C.
AF: Cent. Dosage Elem. Traces, Univ. Nantes, 1, rue Gaston Veil, 44035 Nantes Cedex, France
SO: J.-RECH.-OCEANOGR. 1987. vol. 12, no. 3-4, pp. 81-84
LA: French
ER: M (Marine)
AB: Most studies on biogeochemical cycles concentrate on the water, sediment and suspended matter compartments and do not mention the biological compartment. This is the case when the zinc content in oysters is higher than in the surrounding water or the seston and is equal to that of the oxygenated sediment. This paper discusses the results of an assessment of the metal contents found in the oyster Crassostrea gigas .
AN: 1937161

                                                                   1433 of 1521  
TI: Sensitivity of climate and atmospheric CO sub(2) to deep-ocean and shallow-ocean carbonate burial.
AU: Volk,-T.
AF: Earth Syst. Group, Dep. Appl. Sci., New York Univ., 26 Stuyvesant St., New York, NY 10003, USA
SO: NATURE. 1989. vol. 337, no. 6208, pp. 637-640
LA: English
ER: M (Marine)
AB: Previous models of physical and biogeochemical controls of the evolution of atmospheric CO sub(2) and climate over hundreds of millions of years have neglected the effect of variations in the balance between shallow-ocean and deep-ocean carbonate deposition. A model of the carbonate-silicate geochemical cycle that distinguishes carbonate masses produced by the two types of burial shows that reasonable increases in deep-ocean burial could produce substantial warmings over a few hundred million years. Without the habitation of the open ocean by plankton such as forminifera and coccolithophores, today's climate would be substantially colder.
AN: 1931843

                                                                   1434 of 1521  
TI: Rate of production, dissolution and accumulation of biogenic solids in the ocean.
AU: Arrhenius,-G.
AF: Scripps Inst. Oceanogr., Univ. California at San Diego, La Jolla, CA 92093-0220, USA
CO: 2. Hans Pettersson Series of Symposia in Oceanography: Southern Ocean -- The Antarctic: Present and Past, (Sweden), 21-25 Apr 1987
SO: THE-SOUTHERN-OCEAN-THE-ANTARCTIC:-PRESENT-AND-PAST. Olausson,-E.-ed. 1988. vol. 67, no. 1-2 pp. 119-146
ST: PALAEOGEOGR.,-PALAEOCLIMATOL.,-PALAEOECOL. vol. 67, no. 1-2
NT: Special issue.
LA: English
ER: M (Marine)
AB: A permanant record of the changes in rate of upwelling and organic production is generated in the equatorial deep sea sediments, particularly by such biogenic components which are unaffected by secondary dissolution. In order to determine the rates of accumulation of various sedimentary components, a reliable differential measurement of age of the strata must be obtained. Various approaches to this problem are reviewed. Secondary dissolution of calcium carbonate introduces a substantial and variable difference between the dissolution-modified, and hence a priori unknown, rate of deposition on one hand and the rate of accumulation, derivable from the observed concentration, on the other. As a most likely cause of the enhanced state of dissolution of the interglacial carbonate sediments is proposed the lowered rates of biogenic production and deposition, which cause longer exposure of the carbonate microfossils to corrosion in the bioturbated surface layer of the sediment.
AN: 1931028

                                                                   1435 of 1521  
TI: Suspended manganese-rich particles in Kau Bay, Halmahera (eastern Indonesia).
AU: Sloot,-H.A.-Van-Der; Hoede,-D.; Hamburg,-G.; Lange,-G.J.-De; Middelburg,-J.J.; Sophiah,-S.
AF: Netherlands Energy Res. Found., P.O. Box 1, 1755 ZG Petten, Netherlands
SO: MAR.-GEOL. 1988. vol. 82, no. 3-4, pp. 251-259
LA: English
ER: M (Marine)
AB: Suspended particulate matter from Kau Bay, Halmahera has been collected by continuous-flow centrifugation of water samples. On examination by scanning electron microscopy a variety of Mn-rich particles has been found. The most abundant particles are spherical and fairly uniform in size. These particles feature a remarkably uniform cavity on one side and are intimately involved in the geochemical cycling of Mn in Kau Bay. Particles of this form have not been observed before but are likely to occur in comparable open-ocean suboxic water. It is suggested that the formation of microbially mediated Mn particulates is enhanced by the high water temperature, whereas inorganic Mn precipitates are more likely to be found in low-temperature waters.
AN: 1928312

                                                                   1436 of 1521  
TI: Temporal dynamics of an estuary: San Francisco Bay.
AU: Cloern,-J.E.; Nichols,-F.H.-(eds.)
SO: DEV.-HYDROBIOL. 1985. no. 30, 237 pp
LA: English
ER: M (Marine); B (Brackish)
AB: The fourteen papers cover topics from the general physical characteristics of the estuary through a review of many of its chemical and biological communities. The papers address the changes within the various systems over time; time scales usually being seasonal and/or multiyear. After a brief discussion of the estuary's geology and physical oceanography, the papers progress through the biogeochemical basics (nutrients, chemicals, gases), exchanges with the bottom sediments and atmosphere, the benthos, and then up the chain of macroalgae, phytoplankton, zooplankton, shrimp, and fishes, finishing with a wrap-up paper by the editors.
AN: 1923864

                                                                   1437 of 1521  
TI: In situ deep water particle sampler and real-time sensor package with data from the Madeira Abyssal Plain.
AU: Simpson,-W.R.; Gwilliam,-T.J.P.; Lawford,-V.A.; Fasham,-M.J.R.; Lewis,-A.R.
AF: Inst. Oceanogr. Sci., Brook Rd., Wormley, Godalming, Surrey GU8 5UB, UK
SO: DEEP-SEA-RES. 1987. vol. 34, no. 8A, pp.  1477-1497
LA: English
ER: M (Marine)
AB: A deep water particle sampler was designed to measure physical variables in real time and collect particulate and water samples in situ with the view to furthering our understanding of biogeochemical cycles. Profiles of particulate concentration, particle size distribution (10-200  mu m) and temperature against depth are taken on the outward and return casts to a maximum depth of 6000 m. Particle samples are collected by large volume filtration at four depths preselected on the basis of outward cast data. For metal analyses, 1  mu m polycarbonate membranes are used, and glass fibre filters for organic analysis; larger particles may be collected by prefilters of any chosen mesh size. Data presented from the Madeira Abyssal Plain illustrate the function of the instrument and the results are compared to those reported previously.
AN: 1922658

                                                                   1438 of 1521  
TI: Dissolved arsenic in waters of the Cape Basin.
AU: Statham,-P.J.; Burton,-J.D.; Maher,-W.A.
AF: Dep. Oceanogr., Univ. Southampton, Southampton SO9 5NH, UK
SO: DEEP-SEA-RES. 1987. vol. 34, no. 8A, pp. 1353-1359
LA: English
ER: M (Marine)
AB: Measurements of dissolved arsenic have been made on water samples from various depths at six stations in the Cape Basin, using hydride generation and graphite furnace atomic absorption spectrophotometry. Methylated forms of arsenic were not determined under the conditions used. Concentrations in samples from depths shallower than 110 m averaged 19.9 nmol/l (range 17.6-22.8 nmol/l) for all stations. Five stations had water depths greater than about 4000 m, and for these the mean concentration in waters below 110 m was 21.1 nmol/l (range 17.6-23.8 nmol/l super(-1)). The difference in concentration between the upper (< 110 m) and deeper waters was statistically significant. Somewhat higher concentrations of 22.0-27.5 nmol/l were found for water below 110 m at the station nearest shore, whose water depth was about 2200 m. The findings are consistent with the view that the major consequence of the uptake of arsenic by microorganisms is cycling between chemical forms within the euphotic zone and that the flux of arsenic into the deep ocean by transport with particles is minor, relative to the concentration of the element in the oceanic reservoir.
AN: 1922522

                                                                   1439 of 1521  
TI: Iodine speciation in Chesapeake Bay waters.
AU: Luther,-G.W.,III; Cole,-H.
AF: Coll. Mar. Stud., Univ. Delaware, Lewes, DE 19958, USA
SO: MAR.-CHEM. 1988. vol. 24, no. 3-4, pp. 315-325
LA: English
ER: B (Brackish)
AB: The authors report on the speciation of iodine in Chesapeake Bay during July 1986. Surface and bottom water samples were taken along the estuary at every 1-2 ppt salinity division. At three locations in the upper bay, samples were taken above, at and below the pycnocline. All samples were analyzed by differential pulse polarography. Iodate was determined directly. Total iodine (including organic forms) was determined by hypochlorite oxidation to iodate. Iodide is defined as the difference between these two analyses. Total iodine appears to be conservative in the estuary. In all samples from the upper bay only reduced forms of iodine were present. Iodine is maintained in its reduced state by biological processes in the surface waters and by a combination of biological and chemical processes in the anoxic bottom waters.
AN: 1918487

                                                                   1440 of 1521  
TI: Dissolved iodine behavior in estuaries along the East Coast of the United States.
AU: Ullman,-W.J.; Luther,-G.W.,III; Aller,-R.C.; Mackin,-J.E.
AF: Coll. Mar. Stud., Univ. Delaware, Lewes, DE 19958, USA
SO: MAR.-CHEM. 1988. vol. 25, no. 2, pp. 95-106
LA: English
ER: B (Brackish)
AB: Previous studies of dissolved iodine behavior in estuaries have shown no evidence of iodine's participation in biogeochemical processes. Three estuaries along the United States' Atlantic coast clearly show the results of iodine reactivity in biological and/or particle processes. Major factors involved in controlling the iodine speciation and distribution in estuaries include: (i) remineralization of iodine-containing organic matter in sediment or anoxic bottom water; (ii) anthropogenic inputs; (iii) resuspension of fine-grained sediments and their associated interstitial water; and (iv) estuarine flow regime and residence time.
AN: 1918362

                                                                   1441 of 1521  
TI: Influences of river flow on the dynamics of phytoplankton production in a partially stratified estuary.
AU: Malone,-T.C.; Crocker,-L.H.; Pike,-S.E.; Wendler,-B.W.
AF: Horn Point Environ. Lab., Univ. Maryland Cent. Environ. and Estuar. Stud., P.O. Box 775, Cambridge, MD 21613, USA
SO: MAR.-ECOL.-PROG.-SER.. 1988. vol. 48, no. 3, pp. 235-249
NT: Incl. 43 ref.
LA: English
ER: B (Brackish)
AB: Seasonal variations in biomass of the phytoplankton of the Chesapeake Bay are correlated with riverine nitrate input while seasonal variations in productivity are correlated with light and temperature. Evidence is presented which suggests that the spring flux of nitrogen from the watershed and the summer productivity maximum are coupled via the accumulation and sedimentation of phytoplankton biomass during spring and subsequent recycling of regenerated nitrogen into the euphotic zone during summer.
AN: 1907754

                                                                   1442 of 1521  
TI: Remote sensing of ocean colour for studies of biological productivity and biochemical cycles.
AU: Holligan,-P.M.; Morel,-A.
CA: Marine Biological Assoc. Plymouth, (UK)
CO: Ocean Color Workshop, Villefranche-sur-Mer (France), 5-6 Nov 1986
SO: OCEAN-COLOR-WORKSHOP. Guyenne,-T.D.-ed. 1987. pp. 19-22
NT: NTIS Order No.: N88-16296/1/GAR. Rec'd 1988.
RN: ESA-SP-1083 (ESASP1083)
LA: English
ER: M (Marine)
AB: The use of ocean color to assess marine biological resources, to study photosynthetic processes (biomass primary production), and to follow biogeochemical cycles (such as CO2 exchange between atmosphere and ocean, and phytoplankton effects on the carbon cycle) is discussed. Aerosol and sediment studies using narrow band visible scanners such as the Coastal Zone Color Scanner to examine materials exchange are mentioned. Steps which must be taken to exploit ocean color imagery in prediction of global environmental change are listed.
AN: 1903774

                                                                   1443 of 1521  
TI: Biogeochemical cycle of mercury species in the marine environment. Final report for the period 1 May 1986-30 March 1987.
AU: Branica,-M.
CA: International Atomic Energy Agency, Vienna (Austria)
SO: 1987. 14 pp
NT: NTIS Order No.: DE88700798/GAR. Rec'd 1988.
RN: IAEA-R-3295-F (IAEAR3295F)
LA: English
ER: M (Marine)
AB: Mercury contamination of the coastal marine environment is an important concern as toxic methylmercury may be formed biogenically in sediments rich in organic matter. The present study was conducted using a sensitive adaptation of Cold Vapour Atomic Absorption Spectrophotometry in which mercury was re-mineralised from a variety of marine matrices, separated and concentrated by ion-exchange chromatography, trapped as an amalgam in gold wool and subsequently re-released by heating to 900 deg. C. Total and organomercury forms were detected respectively by measuring, in the case of seawater, sample extracts treated and untreated with uv light and, in the case of solid matrices, by "total digestion: and HCl extractions.
AN: 1903695

                                                                   1444 of 1521  
TI: The geochemistry of interstitial water for a sediment core from the Indian River Lagoon, Florida.
AU: Gu,-D.; Iricanin,-N.; Trefry,-J.H.
AF: Dep. Oceanogr. and Ocean Eng., Florida Inst. Technol., Melbourne, FL 32901, USA
SO: FLA.-SCI. 1987. vol. 50, no. 2, pp. 99-110
LA: English
ER: B (Brackish)
AB: Chemical results for interstitial water from organic-rich sediments in the Indian River Lagoon, Florida, show a classic picture of biogeochemical reactions in anoxic environments. Interstitial nitrate was depleted throughout the sediment column and complete sulfate reduction was observed at a depth of > 9 cm below the seawater-sediment interface. Interstitial water chlorinity decreased sharply with depth suggesting subsurface occurrence or intrusion of groundwater. Ammonia, phosphate and silica concentrations were high showing significant nutrient regeneration. Dissolved sulfide levels were also high and play a primary role in controlling interstitial water metal concentrations.
AN: 1902990

                                                                   1445 of 1521  
TI: Acid deposition and nutrient leaching from deciduous vegetation and podzolic soils at the Turkey Lakes Watershed.
AU: Foster,-N.W.; Nicolson,-J.A.
AF: Canadian For. Serv., P.O. Box 490, Sault Ste. Marie, Ont. P6A 5M7, Canada
SO: TURKEY-LAKES-WATERSHED-STUDY. 1988. vol. 45, no. suppl. 1 pp. 96-100
ST: CAN.-J.-FISH.-AQUAT.-SCI. vol. 45, no. suppl. 1
LA: English
ER: F (Freshwater)
AB: Mean annual ion concentrations and ion fluxes in precipitation induced by contact with a maple-birch forest and soil were determined for 1981-85 at the Turkey Lakes Watershed (47 degree 03'N, 84 degree 15'W). Neutralization of atmospherically deposited H super(+) was effected by the canopy and mineral soil. Sulphate was an important counterion for K super(+) leached from the vegetation. Acid deposition had a minor impact on the quality of stemflow and forest floor percolate, which were enriched in K super(+) and Ca super(2+) mobilized in association with organic anions. Calcium and Mg super(2+) were leached from the mineral soil in association with SO sub(4) super(2) super(-) and NO sub(3) super(-). Sulphate was derived largely from acid deposition, and NO sub(3) super(-) from both precipitation and nitrification of native soil N.
AN: 1901508

                                                                   1446 of 1521  
TI: Water and chemical budgets for terrestrial basins at the Turkey Lakes Watershed.
AU: Nicolson,-J.A.
AF: Canadian For. Serv., P.O. Box 490, Sault Ste. Marie, Ont. P6A 5M7, Canada
SO: TURKEY-LAKES-WATERSHED-STUDY. 1988. vol. 45, no. suppl. 1 pp. 88-95
ST: CAN.-J.-FISH.-AQUAT.-SCI. vol. 45, no. suppl. 1
LA: English
ER: F (Freshwater)
AB: Twenty terrestrial basins ranging in area from 2.3 to 62.7 ha were monitored in the 1050-ha Turkey Lakes Watershed (TLW) to measure discharge and ion loss from the terrestrial ecosystem and to estimate terrestrial contributions to the main aquatic system. These basins span 400 m of elevation, beginning at 60 m above Lake Superior (183 m a.s.l.). Annual streamflow represented 28-63% of precipitation; 30-60% of the total occurred during springmelt. Precipitation quantity and SO sub(4) super(2) super(-) and NO sub(3) super(-) input were measured at the Atmospheric Environment Service APN station southeast of the TLW; other chemical parameters were measured on samples collected near the main outlet on the west side of the TLW.
AN: 1901501

                                                                   1447 of 1521  
TI: (The role of biosedimentation in the formation of bottom deposits.).
OT: Kvoprosu o roli biosedimentatsii v obrazovanii donnykh otlozhenij
AU: Savenko,-V.S.
AF: Gos. Univ., Moscow, USSR
SO: VODN.-RESUR. 1988. no. 4, pp. 120-129
LA: Russian
AB: Recent data on the granulometric composition of deposits and intensity of actual sedimentation collected at various points of the World Ocean are analysed. Suspended particles of 200-300  mu m are found to settle on bottom according to Stokes law. Physical sedimentation as such does not provide for similarity in the granulometric composition of particulate suspended matter and bottom sediments. The daily filtering potential of zooplankton is 3-6 x 10 super(6) km super(3) of ocean water which results in the separation of about 220-440 billon tons of suspended matter annually, and points to the repeated processing of suspension by zooplankton.
AN: 1880609

                                                                   1448 of 1521  
TI: Binding of manganese by Antarctic Phaeocystis pouchetii  and the role of bacteria in its release.
AU: Davidson,-A.T.; Marchant,-H.J.
AF: Antarctic Div., Dep. Sci., Channel Highway, Kingston, Tas. 7150, Australia
SO: MAR.-BIOL. 1987. vol. 95, no. 3, pp. 481-487
NT: Incl. 46 ref.
LA: English
ER: M (Marine)
AB: The growth of Antarctic Phaeocystis pouchetii  and associated bacteria in culture, and the binding and release of manganese were investigated using cultures derived from three clonal isolates collected from Prydz Bay, Antarctica, in Nov and Dec 1982. The cultured strains accumulated manganese from the culture medium. The concentration of Mn super(2+) in the alga up to 58 times that of the medium. The Mn super(2+) apparently binds to the mucilage secreted by the cells and gives the alga its characteristic  brown colour. Once the growth of P. pouchetii  and production of acrylic acid slow, bacterial numbers increase, leading to the solubilization of the mucilage and the release of Mn super(2+).
AN: 1874938

                                                                   1449 of 1521  
TI: Glycolate turnover in the water column of the New York Bight apex.
AU: Edenborn,-H.M.; Litchfield,-C.D.
AF: Oak Ridge Res. Inst., 113 Union Valley Rd., Oak Ridge, TN 37830, USA
SO: MAR.-BIOL. 1987. vol. 95, no. 3, pp. 459-467
NT: Incl. 53 ref.
LA: English
ER: M (Marine)
AB: Heterotrophic bacterial uptake and turnover of glycolate were measured in the water column of the New York Bight apex during four seasonal cruises over almost a one-year period between May 1977 and Mar 1978. Glycolate turnover was most rapid in May and Jul, when primary productivity and estuarine runoff were high. Glycolate flux calculations indicate that the measured rates of glycolate consumption by bacteria always exceeded estimated glycolate production by phytoplankton, except in Mar. This excess may reflect an under-estimation of phytoplankton production or the input of glycolate from other sources, such as estuarine runoff. Glycolate utilization appears to be seasonally important to bacteria in the New York Bight apex, coinciding with fluctuations in phytoplankton primary productivity.
AN: 1874329

                                                                   1450 of 1521  
TI: Acidic deposition impacts mediated by sulfur cycling in a coastal plain forest ecosystem.
AU: Morgan,-M.D.; Good,-R.E.; Spratt,-H.G.,Jr.
AF: Rutgers Univ., Dep. Biol. and Div. Pinelands Res., Camden, NJ 08102, USA
CO: 14. International Botanical Congress, Berlin (FRG), 1987
SO: GEOJOURNAL. 1988. vol. 17, no. 2, pp. 183-187
LA: English
ER: F (Freshwater)
AB: Deposition in the New Jersey Pinelands was very acidic (pH = 4.17) and contained high levels of SO sub(4) super(-) super(2) based on bulk deposition measurements from July 1984-July 1986. Streamwater over the same interval in undisturbed watersheds was less acidic (pH = 4.52) and had proportionately less SO sub(4) super(-) super(2). A preliminary alkalinity budget for undisturbed watersheds suggested that SO sub(4) super(-) super(2) retention within Pinelands watersheds accounted for a large portion of the total alkalinity generated and thereby lessened the impact of acidic deposition on surface waters. The only process capable of explaining the retention of SO sub(4) super(-2) was microbial sulfate reduction in the extensive wetlands surrounding Pinelands streams which occurred at high rates.
AN: 1868105

                                                                   1451 of 1521  
TI: Selenate reduction by bacteria from a selenium-rich environment.
AU: Maiers,-D.T.; Wichlacz,-P.L.; Thompson,-D.L.; Bruhn,-D.F.
AF: Idaho Natl. Eng. Lab., Idaho Falls, ID 83415-2203, USA
SO: APPL.-ENVIRON.-MICROBIOL. 1988. vol. 54, no. 10, pp. 2591-2593
LA: English
ER: F (Freshwater)
AB: Samples collected from Kesterson Reservoir were screened for bacterial presence and selenate reduction capability. Selenate concentrations of 100 mg/liter were not toxic to indigenous bacteria. Of the 44 samples collected, 20 possessed microbial populations capable of reducing selenate. Reduction was observed in 4% of the water samples, 92% of the sediment samples, and 100% of the soil samples. Microbial reduction of 100 mg of selenate per liter was complete within 1 week of incubation. Up to 75 mg of selenate per liter was reduced beyond selenite to an insoluble red precipitate. Data collected indicate that indigenous bacteria have a significant role in the biogeochemical cycling of selenium.
AN: 1867116

                                                                   1452 of 1521  
TI: (Metal and phosphorus recycling by Scirpus americanus  and Spartina alterniflora  in the middle Saint Lawrence Estuary (Quebec).).
OT: Recyclage des metaux et du phosphore par Scirpus americanus  et Spartina alterniflora  dans l'estuaire moyen du Saint-Laurent (Quebec)
AU: Deschenes,-J.; Serodes,-J.-B.
AF: Dep. Genie Civil, Univ. Laval, Que. G1K 7P4, Canada
SO: NAT.-CAN. 1986. vol. 113, no. 2, pp. 143-151
LA: French
ER: B (Brackish)
AB: This study attempting to evaluate the contribution of Scirpus americanus  and Spartina alterniflora  to the recycling of heavy metals and nutrients shows that the concentrations of Cu, Zn, K and P in the aboveground portion of these plants decrease during the growing season and degenerescence of the plants. The amounts of heavy metals and nutrients absorbed by these plants show a progression similar to that of the biomass, but they remain considerably less than those present in the sediments.
AN: 1865846

                                                                   1453 of 1521  
TI: Biogeochemical cycling of the elements in some fresh water algae from gold and uranium mining districts.
AU: Mann,-H.; Fyfe,-W.S.
AF: Geol. Dep., Univ. Western Ontario, London, Ont. N6A 5B7, Canada
SO: BIORECOVERY. 1988. vol. 1, no. 1, pp. 3-26
LA: English
ER: F (Freshwater)
AB: The contribution of fresh water algae to the retardation of heavy metal dispersion from mine tailing environments at Elliot Lake and Timmins, Canada has been examined. Algae samples from acid tailing drainage at Elliot Lake typically contained  approximately equals  20 ppm U, and up to a maximum of 0.13% U by weight. Other metals which include Al, Ti, Pb, Zn, Ba, Cu, Ni, Mo, Th, Be and Zr, were also concentrated by algae. The water-sediment system from the Stanrock tailings sites revealed crystallized  gamma -lepidocrocite in Euglena  sp. Filamentous algae from Pearl Lake, near Timmins, also contain significant quantities of metals with concentrations 10 super(4) to 10 super(6) times that of the mine discharge water, and gold at up to 10 super(6) times the aqueous input concentration of mine process waters.
AN: 1853175

                                                                   1454 of 1521  
TI: Zinc, chromium, vanadium and iron in the Mediterranean Sea.
AU: Sherrell,-R.M.; Boyle,-E.A.
AF: Dep. Earth, Atmos., and Planet. Sci., Massachusetts Ins. Tech., Rm. E34-200, Cambridge, MA 02139, USA
SO: DEEP-SEA-RES. 1988. vol. 35, no. 8A, pp. 1319-1334
LA: English
ER: M (Marine)
AB: Mediterranean surface waters contain elevated levels of Zn and Cr and slightly lower levels of V compared to similar nutrient-depleted open ocean waters. A detailed mapping of surface concentrations in the Alboran Sea (immediately E of the Strait of Gibraltar) reveals that maximum total dissolvable concentrations of Zn (9.4 nmol/kg), Cr (3.9 nmol/kg), V (35 nmol/kg) and total Fe (53 nmol/kg) occur in the core of the Atlantic inflow jet. These distributions imply that a portion of Mediterranean trace metal enrichment occurs during passage of surface water through the coastal region and into the Strait, as observed previously for Cu and Cd. Cr and V levels in Mediterranean deep water are similar to surface water concentrations near deep-water formation regions, but Zn is enriched in deep water, implying some vertical transport by biological cycling. A simple steady-state box model indicates that about 30% of the Zn transport is particulate and that the Zn : nutrient ratio in sinking particulate matter is similar to that in open ocean particulates.
AN: 1852525

                                                                   1455 of 1521  
TI: Ammonium and phosphate uptake rates, N:P supply ratios, and evidence for N and P limitation is some oligotrophic lakes.
AU: Suttle,-C.A.; Harrison,-P.J.
AF: Dep. Bot. and Oceanogr., Univ. British Columbia, 6270 University Blvd., Vancouver, B.C. V6T 1W5, Canada
SO: LIMNOL.-OCEANOGR. 1988. vol. 33, no. 2, pp. 186-202
LA: English
ER: F (Freshwater)
AB: Natural assemblages of freshwater phytoplankton were grown in daily-dilution culture (0.50/d) at six N:P supply ratios (5:1, 10:1, 15:1, 25:1, 35:1, and 45:1; by atoms), to create a range of N- and P-limited conditions. After a minimum of 30 d in culture, subsamples were removed for determination of saturated phosphate (PO sub(4)@)u3 super(-)) and ammonium (NH sub(4)@)u+) uptake rates. A relationship (y = 0.0148e exp(0.1496x)) was found between the ratio of PO sub(4)@)u3 super(-) to NH sub(4)@)u+ uptake rates (y) and N:P supply ratio (x), indicating that this index was sensitive to the N:P supply ratio under which phytoplankton are grown. Cultures grown at the highest ratio were dominated by a chroococcoid cyanobacterium (probably Synechococcus) sp.), while those grown at the two lower ratios were dominated by the diatoms Nitzschia  and Synedra  and the chlorophyte Scenedesmus . Additional experiments were conducted on two oligotrophic lakes in an effort to determine if N and P co-occurred as limiting resources. Nutrient bioassay studies on water from one of these lakes indicated that N was in short supply among members of the phytoplankton community.
AN: 1849754

                                                                   1456 of 1521  
TI: The dissolution kinetics of diatom ooze from the Antarctic area.
AU: Kamatani,-A.; Ejiri,-N.; Treguer,-P.
AF: Lab. Marine Chem., Tokyo Univ. Fisheries, Minato-ku, Tokyo 108, Japan
SO: DEEP-SEA-RES. 1988. vol. 35, no. 7A, pp. 1195-1203
LA: English
ER: M (Marine)
AB: The dissolution kinetics of Antarctic diatom ooze was investigated in seawater at various pH's and temperatures. The slow dissolution rate of the ooze was mostly due to the presence of inhibitors postfixed on the surface layer of silica skeletons, which partly were removed by the acid treatment; inhibitors reformed gradually around the surface of acid-cleaned skeletons. The dissolution process was quite different from that of silica skeletons prepared from living diatoms, and could be described by parabolic kinetics; the concentration of dissolved silica from the diatom ooze is proportional to square root of time.
AN: 1840414

                                                                   1457 of 1521  
TI: Chlorinated hydrocarbons in the open Mediterranean ecosystem and implications for mass balance calculations.
AU: Burns,-K.A.; Villeneuve,-J.P.
AF: Int. Lab. Mar. Radioact., Musee Oceanogr., MC-98000, Monaco
SO: MAR.-CHEM. 1987. vol. 20, no. 4, pp. 337-359
LA: English
ER: M (Marine)
AB: Studies on the biogeochemical cycling of organic contaminants in the Mediterranean have demonstrated the importance of polychlorinated biphenyls (PCBs) as relatively stable markers of recent anthropogenic influence in ocean systems. This paper presents results of hydrocarbon analyses of deep water profiles, sediments and their associated surface flocculent layers, and zooplankton samples collected in the western basin. Analytical results are placed in the context of other distribution data for PCBs and long-term flux studies to construct a partial mass balance budget for this semi-enclosed sea. The computed coastal inventory showed that 35% remains suspended in the water column while the majority of residues are deposited in coastal sediments. However in the open sea, the deep water column may contain up to 70% of the total inventory and may be a continually increasing reservoir of stable organic contaminants.
AN: 1831438

                                                                   1458 of 1521  
TI: Stoichiometry of C, N, P, and Si fluxes in a temperate-climate embayment.
AU: Smith,-S.V.; Wiebe,-W.J.; Hollibaugh,-J.T.; Dollar,-S.J.; Hager,-S.W.; Cole,-B.E.; Tribble,-G.W.; Wheeler,-P.A.
AF: Hawaii Inst. Mar. Biol., Univ. Hawaii, Honolulu, HI 96822, USA
SO: J.-MAR.-RES. 1987. vol. 45, no. 2, pp. 427-460
LA: English
ER: M (Marine)
AB: Dissolved C, N, P, and Si budgets for Tomales Bay, California, have been used to solve simultaneous stoichiometric equations which describe a plausible material balance for net organic matter reactions in the bay. Dissolved Si and P were both exported hydrographically. Dissolved C and fixed N were imported hydrographically. If one assumes that C, N, P, ans Si were supplied to the bay as organic detritus and remineralized at a rate required to balance dissolved Si and P exports, one can calculate reasonable rates of denitrification and CO sub(2) gas evasion across the air-water interface. The system is thus interpreted to have been net heterotrophic at the time of the investigation.
AN: 1827611

                                                                   1459 of 1521  
TI: Manganese oxidation in pH and O sub(2) microenvironments produced by phytoplankton.
AU: Richardson,-L.L.; Aguilar,-C.; Nealson,-K.H.
AF: NASA Ames Res. Cent., Mail Stop 242-4, Moffett Field, CA 94035, USA
SO: LIMNOL.-OCEANOGR. 1988. vol. 33, no. 3, pp. 352-363
LA: English
ER: F (Freshwater)
AB: Pure cultures of Chlorella  sp. catalyzed the oxidation of soluble Mn(II) to particulate, extracellular, manganic oxides. Manganese oxidation was dependent on photosynthetic activity: no oxidation was observed in the dark when cells were grown heterotrophically on glucose, or in the light when photosystem II was inhibited by the addition of DCMU. Manganates were not formed when media were buffered below pH 8.0, suggesting that an important driving force for manganese oxidation was the high pH resulting from photosynthesis. Field studies with minielectrodes in Oneida Lake, New York, demonstrated steep gradients of O sub(2) and pH and the presence of particulate manganic oxides associated with pelagic aggregates of the cyanobacterium Microcystis) sp.
AN: 1825702

                                                                   1460 of 1521  
TI: Biogeochemical studies on the transport of organic matter along the Otsuchi River watershed, Japan.
AU: Wada,-E.; Minagawa,-M.; Mizutani,-H.; Tsuji,-T.; Imaizumi,-R.; Karasawa,-K.
AF: Lab. Biogeochem. and Sociogeochem., Mitsubishi-Kasei Inst. Life Sci., Minamiooya 11, Machida, Tokyo 194, Japan
SO: ESTUAR.-COAST.-SHELF-SCI. 1987. vol. 25, no. 3, pp. 321-336
LA: English
ER: M (Marine); B (Brackish)
AB: The distributions and stable isotope ratios of biogenic nitrogen and carbon were investigated in detail along a small watershed in order to establish a biogeochemical framework for assessing the fate of organic matter. The number of suspended particles and the concentrations of  delta  super(15)N and  delta  super(13)C in the river sediments increased along the watershed, indicating a change from river to marine ecosystems. Dramatic variations of  delta  super(15)N and  delta  super(13)C were observed in the intertidal sediments, where the progress of denitrification, discharge of domestic sewage, and the accumulation and the decomposition of macroalgae and seagrasses took place. Possible factors that influence the variation of stable isotope ratios along the watershed are discussed. The relationship between the sizes of particles and isotope ratios clearly demonstrated that organo-silty-clay minerals with diameter smaller than 64  mu m were the major source of land-derived refractory organics.
AN: 1819034

                                                                   1461 of 1521  
TI: An experiment on the relative importance of denitrification, nitrate reduction and ammonification in coastal marine sediment.
AU: Goeyens,-L.; Vries,-R.T.P.-De; Bakker,-J.F.; Helder,-W.
AF: Netherlands Inst. Sea Res., P.O. Box 59, 1790 Den Burg, Texel, Netherlands
SO: NETH.-J.-SEA-RES. 1987. vol. 21, no. 3, pp. 171-175
LA: English
ER: M (Marine)
AB: Simultaneous determinations of  super(15)N-nitrogen gas production,  super(15)N-ammonia formation by nitrate reduction and ammonia production from organic nitrogen were carried out after addition of  super(15)N-nitrate to anaerobically incubated sediment slurries from a location in the Dutch Wadden Sea. The rate of nitrogen gas production was 1.57  mu mol N multiplied by cm super(-3) wet sediment multiplied by d super(-1), nitrate reduction to ammonia occurred at a rate of 0.79  mu mol N multiplied by cm super(-3) multiplied by d super(-1) and ammonification at 1.17  mu mol N multiplied by cm super(-3) multiplied by d super(-1). At the end of the incubation experiment (after 30 h) 63% of the originally added  super(15)N-nitrate was present as nitrogen gas, 32% ended up as ammonia and  similar to 4% as particulate organic nitrogen. Ammonia production by degradation of organic nitrogen compounds was the most important process in building up the ammonia pool in the anaerobic sediment incubation.
AN: 1806393

                                                                   1462 of 1521  
TI: Primary and bacterial production in the Bering Sea.
OT: Pervichnaya i bakterial'naya produktsiya v Beringovom more
AU: Tsyban'-,-A.V.; Korsak,-M.N.
AF: Goskomgidromet AN S.S.S.R., Moscow, USSR
SO: BIOL.-MORYA-MAR.-BIOL.,-VLADIVOST. 1987. no. 6, pp. 15-21
LA: Russian
ER: M (Marine)
AB: The results of the 1981 summer multipurpose cruise of the R/V Akademik Shirshov  are described, and tabled. Of the 4 major pilot areas surveyed, the maximum phytoplankton production (1.0-3.8 g C/m super(2)/day) and P/B coefficients were found off St. Lawrence Island. Vertical distribution of phytoplankton biomass and production varied among stations, and as a rule, the maximum of biomass was deeper than that of primary production. Bacterial production was about the same at all the stations with the maximum either within the 0-0.5 m layer or at 10-15 m. The share of bacterial production constituted from 0.5 to 150% of organic matter produced by photosynthesis. The average level of phytoplankton production in the sea for the entire vegetation period was estimated at 0.63 g C/m super(2)/day which gave the total yearly production of 2 multiplied by 10 super(8)t C sub(org).
AN: 1797465

                                                                   1463 of 1521  
TI: Studies on the mangrove ecosystem of Jiulong River estuary in China 2. Accumulation and biological cycle of potassium and sodium elements in Kandelia candel  community.
OT: Jiulong Jiangkou hongshulin yanjiu 2. Qiuqie qunluo de Jia, Na jilei he xunhuan
AU: Lin,-Peng; Su,-Lin; Lin,-Qingyang
AF: Dep. Biol., Xiamen Univ., Xiamen, People's Rep. China
SO: ACTA-ECOL.-SIN.-SHENGTAI-XUEBAO. 1987. vol. 7, no. 2, pp. 102-110
LA: Chinese
ER: B (Brackish)
AB: The accumulation and biological cycle of potassium and sodium elements in an artificial 20-year-old Kandelia candel  community in Jiulong River estuary of Fujian Province, China, were studied. The results are given.
AN: 1796161

                                                                   1464 of 1521  
TI: Accumulation of Fe, Mn, Cu and V in body and shells of the Black Sea mussel.
OT: Osobennosti nakopleniya zheleza, margantsa, medi, vanadiya v telakh i rakovinakh chernomorskoj midii
AU: Khrustalev,-Yu.P.; Morozov,-V.M.; Chernousov,-S.Ya.
AF: Gos. Univ., Rostov, USSR
SO: OKEANOLOGIYA-OCEANOLOGY. 1987. vol. 27, no. 6, pp. 934-938
LA: Russian
AB: The rate of assimilation and spatial distribution of the chemical elements in Mytilus galloprovincialis  was found to be dependent on the mussel age and size and on the lithological type of bottom sediments. Maximum concentrations in shells and body were recorded in mussels 35-60 and 10-35 mm long, respectively, inhabiting muddy and carbonate muddy silts whereas the minimum levels were found in those occurring on sandy bottom. The metal concentrations were found to decrease seaward, which can be explained by a corresponding decrease in the levels of river-brought pollutants. It is concluded that the mollusk can be successfully used as an indicator species for pollution control.
AN: 1788854

                                                                   1465 of 1521  
TI: Sources and Biogeochemistry of organic matter in the Delaware Estuary.
AU: Cifuentes,-L.A.
CA: Delaware Univ., Newark (USA)
SO: DISS.-ABST.-INT.-PT.-B--SCI.-and-ENG. 1988. vol. 48, no. 8, 243 pp
NT: Diss. Ph.D.: Order No.: DA8719522.
LA: English
AB: The biogeochemistry of organic matter in Delaware Estuary sediments was studied emphasizing seasonality. Suspended particulate matter and bottom sediments were characterized by determining elemental, molecular (pyrolysis GC-MS), isotopic ( delta  super(13)C and  delta  super(15)N), and lignin composition. Carbon and nitrogen fixed by phytoplankton was the major source of organic matter to the estuary. Seasonal differences were not found in the relative inputs of marine and terrestrial organic matter. Organic content in suspended particulate matter was greatest in the lower estuary and varied seasonally. Bottom sediments had much lower organic content. The C:N in suspended particulate matter indicated marine organic matter. Bottom sediments had higher C:N.
AN: 1782197

                                                                   1466 of 1521  
TI: Distribution of heavy metals in some components of coastal environment of northeastern Baltic Sea.
OT: Raspredelenie tyazhelykh metallov v nekotorykh komponentakh morskoj sredy pribrezhnoj zony Severo-Vostochnoj Baltiki
AU: Pal'-m,-T.; Sergieva,-Z.
AF: Otd. BaltNIRKh, Tallin, USSR
SO: IZV.-AN-EHST.S.S.R.-BIOL.-PROC.-ESTON.S.S.R.-ACAD.-SCI.-BIOL.. 1987. no. 1, pp. 29-36
LA: Russian
ER: M (Marine)
AB: Data are provided on the content of Zn, Cu, Pb, Cd and Fe in water, suspended matter and zooplankton. Correlation coefficients between salinity, pH, depth and suspended and dissolved forms of heavy metals were obtained. It is concluded that physico-chemical properties of suspended matter as a whole can affect significantly heavy metal accumulation in aquatic environment. Seston is supposed to accumulate heavy metals readily and influence their dynamics in water.
AN: 1782063

                                                                   1467 of 1521  
TI: Chlorinated hydrocarbons in individual elements of the North Atlantic ecosystem.
OT: Khlorirovannye uglevodorody v otodel'nykh ehlementakh ehkosistemy Severnoj Atlantiki
AU: Orlova,-I.G.
AF: Otd. GOIN, Odessa, USSR
SO: OKEANOLOGIYA-OCEANOLOGY-MOSC.. 1987. vol. 27, no. 6, pp. 927-933
LA: Russian
ER: M (Marine)
AB: Results are presented of the analysis of distribution of chlorinated hydrocarbons (ChH) in water, hydrobionts and bottom sediments. The levels of ChH are tabulated for 1980-1984 and the patterns of distribution as dependent on physico-geographical characteristics, species composition of zooplankton and mineral composition of bottom sediments are considered. Coefficients of accumulation of ChH in individual hydrobionts and in bottom sediments were determined. The maximum values of distribution coefficients were typical of integral plankton samples.
AN: 1781582

                                                                   1468 of 1521  
TI: Silica and phosphorus flux from sediments: Importance of internal recycling in Lake Michigan.
AU: Conley,-D.J.; Quigley,-M.A.; Schelske,-C.L.
AF: Dep. Fish. and Aquacult., 7922 NW 71st St., Univ. Florida, Gainesville, FL 32606, USA
SO: CAN.-J.-FISH.-AQUAT.-SCI. 1988. vol. 45, no. 6, pp. 1030-1035
LA: English
ER: F (Freshwater)
AB: Estimated lake-wide sediment fluxes of silica and phosphorus (P) were determined and then compared with other components in the biogeochemical cycle to investigate the importance of sediment regeneration in Lake Michigan. Dissolved silica (Si) and soluble reactive phosphorus (SRP) fluxes from sediment were measured by the incubation of intact sediment cores. Differences in the supply rates and in the biogeochemical recycling rates of Si and P can lead to seasonal Si depletion in the water mass and influence the outcome of seasonal phytoplankton species succession by limiting Si availability necessary for diatom production.
AN: 1778277

                                                                   1469 of 1521  
TI: Accumulation and biological cycle of chloride in Bruguiera sexangula  community.
OT: Hainan Dongzhai Gang hailian qunluo lu yuansu de leiji yu shengwu xunhuan
AU: Lian,-Yuwu; Lin,-Peng
AF: Dep. Biol., Xiamen Univ., Xiamen, People's Rep. China
SO: J.-XIAMEN-UNIV.-NAT.-SCI.-XIAMEN-DAXUE-XUEBAO. 1987. vol. 26, no. 3, pp. 359-365
LA: Chinese
ER: B (Brackish)
AB: The accumulation and recycling of chloride in a Bruguiera sexangula  community in Dongzhai Harbour, Hainan Island (China) is discussed. The amount of chloride in the standing crop of this community was 7.05 x 10 super(3) kg/ha. Biomass of the aerial parts and underground parts were found to be 2.19 x 10 super(3) kg/ha and 4.86 x 10 super(3) kg/ha respectively. In this community, the yearly Cl super(-) return and retention were estimated to be 385 kg/ha and 266 kg/ha, hence its yearly uptake could be induced to a value of 651 kg/ha. The chloride recycling period was estimated to be 18 years.
AN: 1776513

                                                                   1470 of 1521  
TI: Carbon and nitrogen budgets in manured fish ponds on Israel's coastal plain.
AU: Schroeder,-G.L.
AF: Agric. Res. Organ., Fish and Aquacult. Res. Stn., Dor, Hof HaCarmel 30820, Israel
SO: AQUACULTURE. 1987. vol. 62, no. 3-4, pp. 259-279
LA: English
ER: F (Freshwater)
AB:  delta C data from manure-loaded, polyculture, freshwater ponds located on Israel's coastal plain, in conjuction with information obtained from gut contents of target fish grown in these ponds, show that 50-80% of the fish yield originated from algal-based food webs harvested primarily after the algae had been processed within the detritus of the pond bottom. The remaining yield originated from manure-based food webs. In manured ponds at Dor, net primary productivity (PP) fixed an average of 5 g carbon/m super(2)/day super(1) in algal growth. Manuring added an average of 3 g organic carbon and 0.3 g inorganic nitrogen/m super(2)/day super(1). Losses of organic matter inherent in the microbial processing of the detritus prior to consumption by target animals require that, to sustain the measured fish yields, more than half of the natural food production was harvested by the target animals. The nitrogen required to sustain the measured PP in Dor ponds depended upon rapid recycling of algal nitrogen via fish and seston community metabolism, and microbial processing of algae precipitated to the detritus.
AN: 1775805

                                                                   1471 of 1521  
TI: Nitrate reduction in marine sediment: Pathways and interactions with iron and sulfur cycling.
AU: Soerensen,-J.
AF: Dep. Ecol. and Genet., Univ. Aarhus, Ny Munkegade, 8000 Aarhus C, Denmark
SO: GEOMICROBIOL.-J. 1987. vol. 5, no. 3-4, pp. 401-422
NT: Special issue: Anaerobic mineralization.
LA: English
ER: M (Marine)
AB: In coastal marine sediments, the interactions between NO sub(3) super(-) reduction and transformations of Fe and S compounds often occur in a strong gradient of electron activity ("redoxcline"). Denitrification activity is observed throughout the NO sub(3) super(-)-containing surface zone, although the reduction step from N sub(2)O to N sub(2) can be inhibited by H sub(2)S in the "redoxcline." Survival of denitrifiers is generally poor in NO sub(3) super(-)-free, reduced sediment; such populations are likely to employ Fe super(3+) reduction in their energy metabolism. At depth, the sediments often contain a larger capacity for "nitrate ammonification" (dissimilatory NO sub(3) super(-) reduction to NH sub(4) super(+)) than for denitrification. The "nitrate ammonification" is found commonly among fermenting bacteria, although SO sub(4) super(2) super(-) reducers may also be involved.
AN: 1774791

                                                                   1472 of 1521  
TI: On the content of some chemical elements in plankton of subantarctic zone of the Pacific Ocean.
OT: O soderzhanii ryada khimicheskikh ehlementov v planktone subantarkticheskoj zony Tikhogo okeana
AU: Lukashin,-V.N.; Shiganova,-T.A.
AF: Inst. Okeanol. AN SSSR, Moscow, USSR
SO: GEOKHIMIYA. 1987. no. 11, pp. 1630-1655
LA: Russian
ER: M (Marine)
AB: From data collected between 56 and 63 degree S during the 30th cruise of the R/V Dmitrij Mendeleev  in December 1982-February 1983 concentrations of chemical elements in sea water and coefficients of their accumulation in plankton are presented. The maximum accumulation in plankton was accounted for by Co and Zr, whereas concentrations of Cr, Mn and Zn, Ni, Fe and Cu, Al, Ti and V, Si and Ca were lower. An inverse relationship was established between concentrations of chemicals in sea water and in plankton.
AN: 1774706

                                                                   1473 of 1521  
TI: (Biogeochemical role of bivalve filter feeders in the Sea of Okhotsk.).
OT: O biogeokhimicheskoj roli dvustvorchatykh mollyuskov-fil'tratorov Okhotskogo morya
AU: Kuznetsov,-A.P.; Sagajdachnyj,-A.Yu.
AF: Inst. Okeanol. AN SSSR, Moscow, USSR
SO: DOKL.-AN-S.S.S.R. 1987. vol. 297, no. 3, pp. 751-754
LA: Russian
ER: M (Marine)
AB: The paper attempts to evaluate filtration activity of the sestonophagous Bivalvia, i.e. the volume of water swept, and the amount of organic matter consumed and transformed to sediments. Data on quantitative distribution of the filtrators at depths down to 1000 m from 3 cruises of the R/V Vityaz  were examined to reveal that at stations made at depths down to 100-150 m, the total filtration rate was between 1 and 101 multiplied by m super(-2) multiplied by h super(-1) whereas at offshore stations it was usually less than 1 1 multiplied by m super(-2) multiplied by h super(-1). Through a series of assumptions the authors evaluate the total yearly volume of water swept by the Okhotsk Sea mollusks on the level of 3,380 km super(3). The mollusk-produced biological production in the 0-1000 m layer is assessed as 134 th. t C per year.
AN: 1774687

                                                                   1474 of 1521  
TI: Biological cycling of cadmium in marine environment.
AU: Ray,-S.; McLeese,-D.W.
AF: Fish. and Environ. Sci., Fish. Res. Branch, Dep. Fish. and Oceans, Biol. Stn., St. Andrews, N.B., Canada
SO: CADMIUM-IN-THE-AQUATIC-ENVIRONMENT. Nriagu,-J.O.;Sprague,-J.B.-eds. 1987. vol. 19 pp. 199-221
ST: ADV.-ENVIRON.-SCI.-TECHNOL. 1987. vol. 19
LA: English
ER: M (Marine)
AB: The vertical distribution of cadmium is controlled by biogeochemical cycles and normally parallels the distribution of nutrients like phosphates, silicates, and nitrates in the water column. The detailed mechanism is not known, but this behavior indicates that cadmium is bioaccumulated by aquatic organisms at the surface and regenerated from the sinking biological debris in deeper waters. Marine organisms bioaccumulate cadmium not only from the aqueous media but also from bottom and suspended sediments and from food. The process may be controlled by physicochemical factors like salinity and temperature. The chemical form of cadmium in the environment is of prime importance in bioaccumulation by marine organisms. The ultimate level of cadmium in the organism is controlled not only by biotic and abiotic processes but also by metabolism of the metal by the organisms.
AN: 1772520

                                                                   1475 of 1521  
TI: Studies on the mangrove ecosystem of the Jiulongjiang River estuary in China. 3. Accumulation and biological cycle of calcium and magnesium in Kandelia candel  community.
AU: Lin,-Peng; Chen,-Ronghua
AF: Dep. Biol., Xiamen Univ., Xiamen, Peoples Rep. China
SO: ACTA-OCEANOL.-SIN.-EN.-ED.. 1986. vol. 5, no. 3, pp. 447-455
LA: English
ER: B (Brackish)
AB: This is a paper dealing mainly with the accumulation and biological cycle of calcium and magnesium elements of the artificial 20-years old Kandelia candel  community in the Jiulongjiang River estuary of Fujian Province, China. The result of measurements is that the quantities of the two elements in the standing crop are (kg/ha) 772.91 for Ca and 526.57 for Mg. In the biological cycle of the two elements, the annual uptakes are 174.86 for Ca and 89.30 for Mg (kg/ha); the amounts of Ca and Mg returned via litter fall are estimated to be (kg/ha/a) 103.28 for Ca and 40.42 for Mg; the annual retention are (kg/ha/a) 71.58 for Ca and 48.88 for Mg, respectively. The turnover periods of Ca and Mg are 8 and 13 years, respectively.
AN: 1761530

                                                                   1476 of 1521  
TI: Measurement of hydrolytic activity and incorporation of dissolved organic substrates by microorganisms in marine sediments.
AU: Meyer-Reil,-L.-A.
AF: Univ., Inst. Meereskd., Abt. Mar. Mikrobiol., Duesternbrooker Weg 20, D-2300 Kiel 1, FRG
SO: MAR.-ECOL.-PROG.-SER.. 1986. vol. 31, no. 2, pp. 143-149
LA: English
ER: M (Marine)
AB: A core-injection technique is described which enables the assessment of microbial activities (extracellular enzymatic cleavage of carbohydrates and proteins, incorporation of dissolved organic substrates into microbial biomass) in natural sediment cores. Microliter portions of substrates were injected at 0.5 cm intervals into natural sediment cores, which were incubated, quick frozen, dissected and analysed. For a proper application of the core-injection technique different parameters were investigated such as volume of substrate injected, significance of diffusion of substrate, concentration of substrate and incubation time, and treatment of samples to account for the non-biological "turnover" of substrates. In depth profiles of sediments from the Kiel Bight (Baltic Sea; FRG), microbial extracellular enzymatic activities were highest in the surface horizons and decreased steadily with sediment depth. Incorporation rates of dissolved organic substrates, however, revealed a more complex depth-dependent variation pattern indicating a pronounced stratification of microbial metabolism in the sediment cores.
AN: 1755861

                                                                   1477 of 1521  
TI: Deposition and decomposition of turtlegrass leaves.
AU: Newell,-S.Y.; Fell,-J.W.; Miller,-C.
AF: Univ. Georgia, Mar. Inst., Sapelo Island, GA 31327, USA
SO: INT.-REV.-GESAMT.-HYDROBIOL. 1986. vol. 71, no. 3, pp. 363-369
NT: Incl. 25 ref.
LA: English
ER: M (Marine)
AB: In coastal zones where prevailing winds are onshore, seagrasses are regularly deposited at the shoreline, often forming large accumulations. The authors compared the rates of output of dry matter, organic carbon, and nitrogen for turtlegrass (Thalassia testudinum ) when it decays at the shoreline or continuously submerged nearby. Output rates were either delayed (by 30 days or more) or were significantly slower for decay under submerged conditions.
AN: 1755623

                                                                   1478 of 1521  
TI: Decomposition in aquatic ecosystems: Summary.
AU: Day,-J.A.
AF: Dep. Zool., Univ. Cape Town, Rondebosch 7700, South Africa
CO: Limnological Society of Southern Africa Congr. on Nutrients and Decomposition: Pathways and Problems in Aquatic Ecosystems, Capetown (South Africa), Jul 1985
SO: J.-LIMNOL.-SOC.-SOUTH.-AFR. 1986. vol. 12, no. 1-2, pp. 123-126
NT: Incl. 15 ref.
LA: English
ER: M (Marine); B (Brackish); F (Freshwater)
AB: Decomposition in aquatic systems in examined, comparing processes in marine, estuarine and freshwater ecosystems. The discussion also highlights aspects that are as yet not fully understood and thus require further investigation.
AN: 1753401

                                                                   1479 of 1521  
TI: Decomposition in pelagic marine ecosystems.
AU: Lucas,-M.I.
AF: Mar. Biol. Res. Inst., Zool. Dep., U.C.T., Rondebosch 7700, South Africa
CO: Limnological Society of Southern Africa Congr. on Nutrients and Decomposition: Pathways and Problems in Aquatic Ecosystems, Capetown (South Africa), Jul 1985
SO: J.-LIMNOL.-SOC.-SOUTH.-AFR. 1986. vol. 12, no. 1-2, pp. 99-122
NT: Incl. bibliogr.: 160 ref.
LA: English
ER: M (Marine)
AB: During the decomposition of plant detritus, complex microbial successions develop which are dominated in the early stages by a number of distinct bacterial morphotypes. The microheterotrophic community rapidly becomes heterogenous and may include cyanobacteria, fungi, yeasts and bactivorous protozoans. Soluble low molecular weight substrates (dissolved organic matter, or DOM) are for the most part rapidly turned over and readily taken up with a high growth efficiency by bacteria although detrital particulate organic material (POM) is turned over slowly and utilized with a low growth efficiency, owing to the structural complexity of the detritus. The presence of appropriate substrate-specific strains of bacteria is important in the decomposition of both DOM and POM. Recent attempts to model decomposition processes and C and N fluxes in pelagic marine ecosystems are described. This review examines the most sensitive components and predictions of the models with particular reference to estimates of bacterial production, net growth yield and predictions of N cycling determined by  super(15)N methodology.
AN: 1753379

                                                                   1480 of 1521  
TI: Decomposition in estuarine ecosystems.
AU: Schleyer,-M.H.
AF: Oceanogr. Res. Inst., P.O. Box 10712, Marine Parade 4056, Durban, South Africa
CO: Limnological Society of Southern Africa Congr. on Nutrients and Decomposition: Pathways and Problems in Aquatic Ecosystems, Capetown (South Africa), Jul 1985
SO: J.-LIMNOL.-SOC.-SOUTH.-AFR. 1986. vol. 12, no. 1-2, pp. 90-98
NT: Incl. bibliogr.: 95 ref.
LA: English
ER: B (Brackish)
AB: The varied sources of estuarine plant detritus and the processes and organisms involved in its decomposition are discussed. In the case of emergent and peripheral vegetation, microbial decomposition commences in the phylloplane, with fairly rapid leaching of DOM occurring soon after immersion. Residual POM, largely cellulose, is decomposed more slowly by cellulolytic micro-organisms. Phytoplankton start contributing to the DOM pool before senescence by excreting soluble substances during normal metabolism and interesting regulatory mechanisms are involved in the bacterial utilization of this material. Bacteria play a more important role than fungi in decomposition and the latter appear to be prominent only in the breakdown of mangrove litter. Predaceous microflagellates and other protists occur in association with the bacteria and feed on them, enhancing decomposition by maintaining optimal bacterial growth rates.
AN: 1753360

                                                                   1481 of 1521  
TI: Decomposition in freshwater ecosystems.
AU: Robarts,-R.D.
AF: Natl. Inst. Water Res., CSIR, P.O. Box 395, Pretoria 0001, South Africa
CO: Limnological Society of Southern Africa Congr. on Nutrients and Decomposition: Pathways and Problems in Aquatic Ecosystems, Capetown (South Africa), Jul 1985
SO: J.-LIMNOL.-SOC.-SOUTH.-AFR. 1986. vol. 12, no. 1-2, pp. 72-89
NT: Incl. bibliogr.: 166 ref.
LA: English
ER: F (Freshwater)
AB: This review examines the sources and composition of organic matter and the decomposition of particulate and dissolved organic matter (POM and DOM) in freshwater ecosystems. Major findings are presented. The data demonstrate that our understanding of decomposition in freshwater ecosystems is deficient. This can be mainly attributed to lack of suitable methodology. Continuing developments in the use of radioisotope technology, exoenzymatic assays and aquatic chemistry permit an optimistic outlook for a better understanding of decomposition processes in fresh waters.
AN: 1753338

                                                                   1482 of 1521  
TI: Urea metabolism and its significance in the nitrogen cycle in the euphotic layer of Lake Biwa. 4: Regeneration of urea and ammonia.
AU: Mitamura,-O.; Saijo,-Y.
AF: Kyoiku Univ., Lab. Environ. Sci. And Educ., Tennoji-ku, Osaka 543, Japan
SO: ARCH.-HYDROBIOL. 1986. vol. 107, no. 4, pp. 425-440
NT: Incl. 45 refs.
LA: English
ER: F (Freshwater)
AB: The regeneration rate of urea and ammonia from zooplankton excretion and microbial mineralization (microbial degradation in the case of urea) was measured in the in situ condition in the euphotic layer at two stations of Lake Biwa. The daily regeneration rate (sum of excretion and mineralization rate) for urea and ammonia was 0.88 and 5.60  mu g-at. N/1/day in a eutrophic area, and 0.14 to 0.46 and 1.10 to 1.27  mu g-at. N/1/day in a mesotrophic area. The contribution of the excretion rate in the regeneration rate ranged from 38 to 64% for urea and 56 to 76% for ammonia. Urea excretion in the total excretion rate was 3 to 30% and the urea mineralization in the total mineralization rate was 10 to 45%. The average ratio of the daily regeneration rate to the daily assimilation rate by phytoplankton was 0.82 for urea and 1.18 for ammonia. Nitrogen supply from the excretion and mineralization through these processes is in a state of dynamic balance with the nitrogen consumption by phytoplankton assimilation, and the urea and ammonia is rapidly recycling in the euphotic layer of Lake Biwa.
AN: 1751324

                                                                   1483 of 1521  
TI: The amino acids uptake of Oscillatoria rubescens  D.C. (blue green algae).
OT: Assimilation des acids amines par Oscillatoria rubescens  D.C. (Cyanophycee)
AU: Feuillade,-M.; Krupka,-H.
AF: INRA, Inst. Limnol., 75, Ave. de Corzent, 74203 Thonon-les-Bains, France
SO: ARCH.-HYDROBIOL. 1986. vol. 107, no. 4, pp. 441-463
NT: Incl. 71 ref.
LA: French
ER: F (Freshwater)
AB: This study was conducted to determine if the blue-green alga from eutrophic lakes: Oscillatoria rubescens  is able to take up amino acids as nitrogen source. A mixture of  super(14)C amino acids was supplied to axenic strain of O. rubescens , incorporation into algal cells were followed by liquid scintillation counting and disappearance of each acid from the medium by thin-layer autoradiochromatography. A.A. were taken up in the light as in the dark at natural low concentration and rapidly metabolized into proteins, assimilation rate increased lightly when the nitrogen cell quota decreased. Uptake occurs also in presence of ammonium salts. Assimilation rate encountered at A.A. natural low concentrations may support low growth rate (generation time: 14 days). Uptake systems of O. rubescens  have high affinities for A.A. (Ks = 0.6  mu M), specially for glycine and serine, suggesting efficient competition capabilities in natural water, for O. rubescens  facing bacteria in presence of dissolved amino acids. The ecological contribution of A.A. may be important as a nitrogen source in conditions where nitrogen is low.
AN: 1750127

                                                                   1484 of 1521  
TI: A model for the dynamics of nutrients and oxygen in the Baltic proper.
AU: Stigebrandt,-A.; Wulff,-F.
AF: Dep. Oceanogr., Univ. Gothenburg, Box 4038, S-400 40 Gothenburg, Sweden
SO: J.-MAR.-RES. 1987. vol. 45, no. 3, pp. 729-759
LA: English
ER: M (Marine)
AB: A horizontally integrated, time-dependent physical-biogeochemical model of high vertical resolution has been developed for the Baltic Sea proper. A seasonal pycnocline model computes the physical state of the mixed surface layer. Below this is an advective-diffusive model. The vertical advection is caused by a time-dependent, entraining bottom current which transports dense seawater into the system. The vertical distributions of volumes and sediment areas are accounted for by the use of the hypsographic function of the system. The chemical/biological processes controlling the distributions of nitrogen and oxygen are modelled. The model has been run for a 20 year period. When compared to the field data the computed dynamics of the mixed layer and the patterns of primary production, nutrients and oxygen appear quite realistic.
AN: 1748326

                                                                   1485 of 1521  
TI: The methodological approaches and some results of the study of the biogeochemical cycle of carbon in the ocean.
AU: Lyutsarev,-S.V.; Romankevich,-E.A.
AF: Inst. Oceanol., USSR Acad. Sci., 21 Krasikova St., Moscow 117218, USSR
CO: 1. Int. Symp. on Integrated Global Ocean Monitoring, Tallinn (USSR), Oct 2-10 1983
SO: INTEGRATED-GLOBAL-OCEAN-MONITORING.-PROCEEDINGS-OF-THE-1ST-INTERNATIONAL-SYMPOSIUM,-TALLINN,-USSR,-OCTOBER-2-10,-1983.-VOLUME-2. USSR-State-Comm.-for-Hydrometeorol.-and-Control-Natural-Environment-USSR 1986. pp. 357-363
LA: English
ER: M (Marine)
AB: The results are presented of investigations conducted regarding the biogeochemical carbon cycle in the ocean, describing also methods used in chemical-analytical investigation of seawater, suspensions and bottom sediments.
AN: 1736603

                                                                   1486 of 1521  
TI: Oceanic branch of the global biogeochemical sulfur cycle.
AU: Ivanov,-M.V.; Lein,-A.Y.
AF: Lab. Biogeochem., USSR Acad. Sci., SCOPE and UNEP Sulfur Unit, USSR
CO: 1. Int. Symp. on Integrated Global Ocean Monitoring, Tallinn (USSR), Oct 2-10 1983
SO: INTEGRATED-GLOBAL-OCEAN-MONITORING.-PROCEEDINGS-OF-THE-1ST-INTERNATIONAL-SYMPOSIUM,-TALLINN,-USSR,-OCTOBER-2-10,-1983.-VOLUME-2. USSR-State-Comm.-for-Hydrometeorol.-and-Control-Natural-Environment-USSR 1986. pp. 325-335
NT: Incl. bibliogr.: 25 ref.
LA: English
ER: M (Marine)
AB: Details are given of investigations conducted in the framework of the SCOPE project "Global Biogeochemical Sulphur Cycle". Two major groups of sulphur fluxes are dealt with: those which contribute sulphur into the ocean reservoir and those which take sulphur from the ocean reservoir to the atmosphere and lithosphere. The sulphur cycle is closely interrelated with the cycles of other elements such as carbon, oxygen and iron.
AN: 1736572

                                                                   1487 of 1521  
TI: Biogeochemical cycle and annual balance of oxygen, phosphorus, silicon and fixed nitrogen in the World Ocean.
AU: Ivanenkov,-V.N.; Konnova,-Y.V.; Konnov,-V.A.
AF: Inst. Oceanol., USSR Acad. Sci., 21 Krasikova St., Moscow 117218, USSR
CO: 1. Int. Symp. on Integrated Global Ocean Monitoring, Tallinn (USSR), 2-10 Oct 1983
SO: INTEGRATED-GLOBAL-OCEAN-MONITORING.-PROCEEDINGS-OF-THE-1ST-INTERNATIONAL-SYMPOSIUM,-TALLINN,-USSR,-OCTOBER-2-10,-1983.-VOLUME-3. USSR-State-Comm.-for-Hydrometeorol.-and-Control-Natural-Environment-USSR 1986. pp. 266-267
LA: English
ER: M (Marine)
AB: Nutrient cycles are ruled by the biochemical processes of photosynthesis and regeneration of organic matter. Details are given of the biogeochemical cycles and annual balances of oxygen, silicon, phosphorus and fixed nitrogen.
AN: 1736203

                                                                   1488 of 1521  
TI: Prospects for global ocean pollution monitoring.
AU: Bennet,-B.G.; Davies,-D.J.A.
AF: Reg. Seas Programme Act. Cent., UNEP, Nairobi, Kenya
CO: 1. Int. Symp. on Integrated Global Ocean Monitoring, Tallinn (USSR), 2-10 Oct 1983
SO: INTEGRATED-GLOBAL-OCEAN-MONITORING.-PROCEEDINGS-OF-THE-1st-INTERNATIONAL-SYMPOSIUM,-TALLINN,-USSR,-OCTOBER-2-10,-1983.-VOLUME-1. USSR-State-Comm.-for-Hydrometeorol.-and-Control-Natural-Environment-USSR 1986. pp. 201-215
NT: Incl. 19 ref.
LA: English
ER: M (Marine)
AB: Factors to be taken into account when conducting monitoring research regarding ocean pollution are examined. Regional and global ocean monitoring programmes are detailed. Requirements and feasibility of open ocean monitoring are examined, considering the air-sea interface, biogeochemical cycles, biological monitoring, background monitoring, monitoring of fisheries resources and remote sensing.
AN: 1734956

                                                                   1489 of 1521  
TI: Ecological investigations in the Bering Sea.
AU: Tsyban,-A.V.; Korsak,-M.N.; Volodkovich,-Yu.L.; McLaughlin,-D.
AF: Nat. Environ. Climate Monit. Lab., USSR Acad. Sci., Moscow, USSR
CO: 1. Int. Symp. on Integrated Global Ocean Monitoring, Tallinn (USSR), 2-10 Oct 1983
SO: INTEGRATED-GLOBAL-OCEAN-MONITORING.-PROCEEDINGS-OF-THE-1st-INTERNATIONAL-SYMPOSIUM,-TALLINN,-USSR,-OCTOBER-2-10,-1983.-VOLUME-1. USSR-State-Comm.-for-Hydrometeorol.-and-Control-Natural-Environment-USSR 1986. pp. 134-157
LA: English
ER: M (Marine)
AB: Long-term observations of the levels of physical, geochemical and hydrobiological processes as well as investigations of ecological and physiological properties of marine organisms in impact and background ocean regions are of importance in assessing the ecological consequences of marine pollution. Studies carried out in the Bering Sea ecosystem are detailed. Hydrological and hydrochemical processes and the biogeochemical cycle of benz(a)pyrene are described and the state of plankton communities, microbiological regime, and the benthos are examined. Elements of the Bering Sea biotic balance are also considered.
AN: 1734898

                                                                   1490 of 1521  
TI: The health of the oceans and the need for its monitoring.
AU: Kullenberg,-G.
AF: Inst. Phys. Oceanogr., Univ. Copenhagen, Haraldsgade 6, 2200, Copenhagen, N. Denmark
CO: 1. Int. Symp. on Integrated Global Ocean Monitoring, Tallinn (USSR), 2-10 Oct 1983
SO: INTEGRATED-GLOBAL-OCEAN-MONITORING.-PROCEEDINGS-OF-THE-1st-INTERNATIONAL-SYMPOSIUM,-TALLINN,-USSR,-OCTOBER-2-10,-1983.-VOLUME-1. USSR-State-Comm.-for-Hydrometeorol.-and-Control-Natural-Environment-USSR 1986. pp. 83-93
LA: English
ER: M (Marine)
AB: An examination is made of the health of the World's Oceans and the importance of an integrated monitoring approach. The conceptual interface-flux model is described, detailing biogeochemical cycles involved. The following contaminants are considered: sewage, PCBs and DDT, petroleum, metals and radionuclides; the problems arising when mixtures of these contaminants occur is also examined.
AN: 1734790

                                                                   1491 of 1521  
TI: Behaviour and ecological importance of a mud snail (Ilyanassa obsoleta ) population in a temperate macrotidal estuary.
AU: Cranford,-P.J.
AF: Dep. Fish. and Oceans, Biol. Sci. Branch, Bedford Inst. Oceanogr., Dartmouth, N.S. B2Y 4A2, Canada
SO: CAN.-J.-ZOOL.-J.-CAN.-ZOOL. 1988. vol. 66, no. 2, pp. 459-466
LA: English
ER: B (Brackish)
AB: A population of Ilyanassa obsoleta  was sampled during the 8-mo. period when they are present in the intertidal zone in the Southern Bight of Minas Basin, Bay of Fundy. During November the population returned to the subtidal zone, where energy reserves are partially utilized during winter. Clustering and differential habitat selection (salt marsh or mud flat) within size classes resulted in large spatial variations in density, standing stock, and production. Production by I. obsoleta  averaged 1.1 g C/m super(-2) during their study in the intertidal zone. The supply of carbon from epibenthic microalgae is insufficient to meet the requirements of this population. Detritus derived from Spartina  is believed to be an important additional source of carbon. Ilyanassa obsoleta  is not a major prey item of any of the better known predators in this region. Their importance to the intertidal community results from the direct (predation) and indirect (competition, disturbance, nutrient regeneration, and bioturbation) influence of their presence on sedimentary microbial processes and the resident benthic flora and fauna.
AN: 1734137

                                                                   1492 of 1521  
TI: Alteration of carbon cycling by beaver: Methane evasion rates from boreal forest streams and rivers.
AU: Ford,-R.J.; Naiman,-R.J.
AF: Div. Appl. Sci., Lab. Microbial Ecol., Harvard Univ., 40 Oxford St., Cambridge, MA 02138, USA
SO: CAN.-J.-ZOOL.-J.-CAN.-ZOOL. 1988. vol. 66, no. 2, pp. 529-533
LA: English
ER: F (Freshwater)
AB: In boreal forest drainage networks, beaver (Castor canadensis ) apparently influence the biogeochemical cycling of carbon by creating conditions for sediment accumulation in streams, providing anoxic conditions suitable for significant methanogenesis. To test this assumption the authors measured methane evasion rates in streams, ranging in size from first to sixth order, in the Matamek River drainage network, Quebec, Canada. Evasion rates varied between 0.04 and 4.41 g C (CH sub(4)) multiplied by m super(-2) multiplied by year super(-1). There was no correlation between stream size or water temperature and evasion rate. However, methane evasion was 33-fold greater in beaver ponds than at other sites, representing 3.6% of the measured annual carbon output.
AN: 1730857

                                                                   1493 of 1521  
TI: The migration process of radionuclides in artificial microhabitat.
AU: Cai,-F.-L.; Chen,-Y.; Xu,-P.-A.
AF: 3rd Inst. Oceanogr., SOA, Xiamen, People's Rep. China
SO: ACTA-OCEANOL.-SIN.-HAIYANG-XUEBAO. 1987. vol. 6, no. 3, pp. 428-433
LA: English
ER: M (Marine)
AB: According to the principle of photosynthesis with sunlight and CO sub(2) by phytoplankton supplying food for marine organisms, while the nitrogenous compounds excreted by marine animals are transferred by bacteria into the nitrate for the use of phytoplankton, an artificial microhabitat was built to investigate comprehensively the distributive relationship of  super(137)Cs,  super(134)Cs,  super(65)Zn,  super(60)Co,  super(59)Fe,  super(54)Mn in the parts of the microhabitat. The results show that 78 ppt. of the  super(134)Cs and  super(137)Cs in ion state are present in sea water, with 28 ppt. of them nearly homogeneously involved in the exchanging processes of the suspensates and organisms, and that 80 ppt. of  super(59)Fe,  super(54)Mn,  super(65)Zn,  super(60)Co were concentrated by solid substance, whose motion was mainly controlled by biological processes. The factors affecting the distribution of nuclides in each composition are discussed. As another type of research on the controlled ecological system, the present study is of reference value for studying quantitatively the migration rule of pollutants in the ocean.
AN: 1730324

                                                                   1494 of 1521  
TI: The behavior of  super(65)Zn in artificial marine microhabitat.
AU: Chen,-Y.; Cai,-F.-L.; Qiu,-M.-H.; Xu,-P.-A.
AF: 3rd Inst. Oceanogr., SOA, Xiamen, People's Rep. China
SO: ACTA-OCEANOL.-SIN.-HAIYANG-XUEBAO. 1987. vol. 6, no. 3, pp. 444-451
LA: English
ER: M (Marine)
AB: The concentration of  super(65)Zn under artificial conditions in suspended matter, sediment, algae, and excretion as well as its distribution in the organs of fish (Tilapia mossambia ), prawn (Penaeus penicillatus ), clam (Arca granosa ), clam (Cyclina sinensis ) were studied. The results show a high concentration factor of suspended matter, with a dynamic equilibrium of concentration by algae arriving after two days. The concentration factor of  super(65)Zn in the intestines of fish, prawn, clam and gills of clam is very high, and their excretive rate is rapid. It was shown that the intestines and gills are critical organs of  super(65)Zn concentration. The content of  super(65)Zn in nucleic acid was highest, and was higher in RNA than in DNA, while that in organic acid was lowest.
AN: 1730322

                                                                   1495 of 1521  
TI: Nitrogen and carbon isotope ratios in seabird rookeries and their ecological implications.
AU: Mizutani,-H.; Wada,-E.
AF: Lab. Biogechem. and Sociogeochem., Mitsubishi-Kasei Inst. Life Sci., 11 Minamiooya, Machida, Tokyo 194, Japan
SO: ECOLOGY. 1988. vol. 69, no. 2, pp. 340-349
LA: English
ER: M (Marine)
AB: Various samples around gull (Larus crassirostris ) and penguin (Pygoscelis adeliae ) rookeries were examined for nitrogen and carbon isotope ratios. The results showed that input of organic nitrogen from avian breeding activity, followed by its aerobic decomposition in soil and by volatilization of the resultant ammonia, strongly dominated nitrogen flow in both rookeries. Plants, animals, and soils in the rookeries appeared dependent on the nitrogen thus provided. Major pathways of material flow in the seabird rookeries were deduced from the isotopic data. Study of stable isotopes should enable the authors to draw similar pictures for other ecosystems; it is particularly useful in places where frequent visits are impractical.
AN: 1725619

                                                                   1496 of 1521  
TI: Benthic respiration measured by total carbonate production.
AU: Anderson,-L.G.; Hall,-P.O.J.; Iverfeldt,-A.; Rutgers-van-der-Loeff,-M.M.; Sundby,-B.; Westerlund,-S.F.G.
AF: Dep. Anal. and Mar. Chem., Chalmers Univ. Technol. and Univ. Goeteborg, S-412 96 Goeteborg, Sweden
SO: LIMNOL.-OCEANOGR. 1986. vol. 31, no. 2, pp. 319-329
LA: English
ER: M (Marine)
AB: The suitability of total carbonate production instead of oxygen sonsumption as a measure of benthic respiration has been investigated. In situ fluxes of total carbonate, oxygen, calcium, total alkalinity, nutrients, and sulfide across the sediment-water interface were measured in diver-operated benthic flux chambers. Two chambers were run in parallel to test the influence of oxygen and pH levels on total carbonate production. In one, oxygen and pH were kept constant near ambient levels, in the other, benthic respiration was allowed to deplete oxygen and lower the pH. The flux of total carbonate, corrected for CaCO sub(3) precipitation/dissolution, was found to be a suitable measure of benthic mineralization in sediments where methane production can be neglected. The production rate of total carbonate was not seriously affected as long as the oxygen concentrations remained > 100  mu M.
AN: 1725074

                                                                   1497 of 1521  
TI: Sulfate reduction in coastal ecosystems.
AU: Skyring,-G.W.
AF: Baas Becking Geobiol. Lab., CSIRO, Div. Water Resour. Res., P.O. Box 1666, Canberra City, A.C.T. 2601, Australia
SO: GEOMICROBIOL.-J. 1987. vol. 5, no. 3-4, pp. 295-374
NT: Special issue: Anaerobic mineralization.
LA: English
ER: M (Marine)
AN: 1719352

                                                                   1498 of 1521  
TI: Trace metals in marine environment in relation to the study of their biogeochemical cycle.
AU: Seritti,-A.; Ferrara,-R.; Morelli,-E.; Barghigiani,-C.; Petrosino,-A.
AF: CNR, Ist. Biofis., Via S. Lorenzo 26, 56100 Pisa, Italy
CO: Symposium on Analytical Problems in Marine Environment, Genoa (Italy), 23-24 May 1983
SO: CHEM.-ECOL. 1986. vol. 2, no. 3, pp. 181-186
LA: English
ER: M (Marine)
AB: Concentrations of cadmium, copper, lead and zinc were measured in the waters of the Tyrrhenian Sea in relation to waste sources and the biogeochemical cycle. These concentrations were not significantly elevated in the abiotic components of the marine environment and it is concluded that they have a low residence time in these waters.
AN: 1709158

                                                                   1499 of 1521  
TI: (Geochemical and chemical behavior of trace elements in the Seine Estuary: Synthesis of discussions.).
OT: Comportement chimique et geochimique des elements a l'etat de traces dans l'estuaire de la Seine: Synthese des discussions
AU: Guegueniat,-P.
AF: Lab. Radioecol. Mar. CEA, BP 270, 50107 Charbourg, France
CO: Colloque National du CNRS, Caen (France), 24 Apr 1985
SO: THE-SEINE-BAY.-CNRS-NATIONAL-COLLOQUIUM,-CAEN,-24-26-APRIL-1985..  LA-BAIE-DE-SEINE.-COLLOQUE-NATIONAL-DU-CNRS,-24-26-AVRIL-1985.- Groupe-de-Recherches-Coordonnees-"Manche"-France;-CNRS,-Paris-France1986. no. 4, pp. 363-368
ST: ACTES-COLLOQ.-IFREMER.
NT: Publ. in Coop. with IFREMER; Minist. Environ.; Caen Univ. (France).
LA: French
ER: M (Marine)
AB: In the synthesis of discussions about the chemistry of the Seine Bay, the author after a note on natural references for metal concentrations, speaks about fluorides, nutrients, PCB, and metallic elements. In conclusion some suggestions about pollutants transfer towards ecosystems link, are enumerated.
AN: 1701530

                                                                   1500 of 1521  
TI: Biological availability of sediment-bound trace metals.
AU: Luoma,-S.N.
AF: U.S. Geol. Surv., Mail Stop 465, 345 Middlefield Rd., Menlo Park, CA 94025, USA
CO: Colloque National du CNRS, Caen (France), 24 Apr 1985
SO: THE-SEINE-BAY.-CNRS-NATIONAL-COLLOQUIUM,-CAEN,-24-26-APRIL-1985..  LA-BAIE-DE-SEINE.-COLLOQUE-NATIONAL-DU-CNRS,-24-26-AVRIL-1985.- Groupe-de-Recherches-Coordonnees-"Manche"-France;-CNRS,-Paris-France1986. no. 4, pp. 347-362
ST: ACTES-COLLOQ.-IFREMER.
NT: Publ. in Coop. with IFREMER; Minist. Environ.; Caen Univ. (France).
LA: English
ER: M (Marine)
AB: It has been established that direct uptake of (at least some) trace metals from sediments contributes to metal concentrations in benthic organisms. Important controls on metal uptake from sediment are the concentration of the exposure, the partitioning of the metals among components of the sediment, and the redox potential of the sediment. Important problems in ecology, physiology, geochemistry and biogeochemistry remain unresolved, however, and a concentrated interdisciplinary research effort will be necessary before a complete understanding of the fate and impact of sediment-bound metals will be possible.
AN: 1701514

                                                                   1501 of 1521  
TI: (Mineral and organic soluble forms of zinc, iron and copper: Distribution in the Seine Estuary.).
OT: Etude de la distribution des formes solubles minerales et organiques du fer, du zinc et du cuivre dans l'estuaire de la Seine
AU: Gandon,-R.; Guegueniat,-P.; Fischer,-J.C.; Wartel,-M.
AF: Lab. Radioecol. Mar., CEA-IPSN-DERS/SERE, BP 270, 50107 Cherbourg, France
CO: Colloque National du CNRS, Caen (France), 24 Apr 1985
SO: THE-SEINE-BAY.-CNRS-NATIONAL-COLLOQUIUM,-CAEN,-24-26-APRIL-1985..  LA-BAIE-DE-SEINE.-COLLOQUE-NATIONAL-DU-CNRS,-24-26-AVRIL-1985.- Groupe-de-Recherches-Coordonnees-"Manche"-France;-CNRS,-Paris-France1986. no. 4, pp. 327-336
ST: ACTES-COLLOQ.-IFREMER.
NT: Publ. in coop. with IFREMER; Minist. Environ.; Caen Univ. (France).
LA: French
ER: M (Marine)
AB: One characteristic of the Seine Estuary system is the process of sediment resuspension by the specific hydrodynamics of this environment. It's the main factor of trace metals transport. Autotrophic activities also have an effect on the estuary, by pH variation. The behavior of soluble and organic copper, iron, have been studied in relation to salinity in and out of the estuary. The results are compared with those of other estuaries.
AN: 1701473

                                                                   1502 of 1521  
TI: (Evolution of metal complexation (Ca, Mg, Cd, Pb, Cu) in the Seine Estuary.).
OT: Evolution de la complexation des metaux (Ca, Mg, Cd, Pb et Cu) dans l'estuaire de la Seine
AU: Fischer,-J.C.; Wartel,-M.
AF: Lab. Chim. Anal. Mar., Univ. Lille 1, Batim. C8, 59655 Villeneuve d'Ascq Cedex, France
CO: Colloque National du CNRS, Caen (France), 24 Apr 1985
SO: THE-SEINE-BAY.-CNRS-NATIONAL-COLLOQUIUM,-CAEN,-24-26-APRIL-1985..  LA-BAIE-DE-SEINE.-COLLOQUE-NATIONAL-DU-CNRS,-24-26-AVRIL-1985.- Groupe-de-Recherches-Coordonnees-"Manche"-France;-CNRS,-Paris-France1986. no. 4, pp. 321-326
ST: ACTES-COLLOQ.-IFREMER.
LA: French
ER: M (Marine)
AB: Interaction between metallic ions and dissolved organic matter can take major part in the biogeochemical cycle of metals in the aquatic environment. The authors point out copper behavior by the study of complexing capacity of surface and bottom waters. A systematic analysis of major elements in natural waters has allowed for a proposal of geographical distribution of metals.
AN: 1701460

                                                                   1503 of 1521  
TI: (The complexing properties of waters in Seine Estuary.).
OT: Pouvoir complexant des eaux de l'estuaire de la Seine
AU: Fischer,-J.C.; Wartel,-M.; Guegueniat,-P.; Gandon,-R.
AF: Lab. Chim. Anal. Mar., Univ. Lille 1, Batim. C8, 59655 Villeneuve d'Ascq Cedex, France
CO: Colloque National du CNRS, Caen (France), 24 Apr 1985
SO: THE-SEINE-BAY.-CNRS-NATIONAL-COLLOQUIUM,-CAEN,-24-26-APRIL-1985..  LA-BAIE-DE-SEINE.-COLLOQUE-NATIONAL-DU-CNRS,-24-26-AVRIL-1985.- Groupe-de-Recherches-Coordonnees-"Manche"-France;-CNRS,-Paris-France1986. no. 4, pp. 315-320
ST: ACTES-COLLOQ.-IFREMER.
NT: Publ. in coop. with IFREMER; Minist. Environ; Caen Univ. (France).
LA: French
ER: M (Marine)
AB: Copper has been studied, by the authors, owing to its ability to complex with various organic ligands of natural waters. Metals extraction and liberation can be explained, in part, by this complexing capacity.
AN: 1701443

                                                                   1504 of 1521  
TI: Variations of upwelling and associated nutrient nitrogen dynamics off the north-west coast of South Island, New Zealand.
AU: Viner,-A.B.; Wilkinson,-V.H.
AF: Taupo Res. Lab., Dep. Sci. and Ind. Res., P.O. Box 415, Taupo, New Zealand
SO: N.Z.-J.-MAR.-FRESHWAT.-RES. 1987. vol. 21, no. 2, pp. 253-266
LA: English
ER: M (Marine)
AB: The surface distribution and metabolic uptake of nitrate and ammonium were investigated as they related to the movements of water in the upwelling zone off the north-west coast of South Island, New Zealand. The movement of water and resulting dispersion from the upwelling focus were shown to differ greatly from day to day; this could confound simple correlations between nutrient nitrate and phytoplankton. A suitable model to investigate metabolic processes due to influx of fertile upwelled water which could avoid this problem can be based upon assays of NO sub(3) and NH sub(4) uptake by the plankton.
AN: 1690192

                                                                   1505 of 1521  
TI: Biogeochemical cycling of selenium in the San Joaquin Valley, California, USA.
AU: Presser,-T.S.; Ohlendorf,-H.M.
AF: U.S. Geol. Surv., 345 Middlefield Rd. (MS-435), Menlo Park, CA 94025, USA
SO: ENVIRON.-MANAGE. 1987. vol. 11, no. 6, pp. 805-821
LA: English
ER: F (Freshwater)
AB: Subsurface agricultural drainage waters from western San Joaquin Valley, California, were found to contain elevated concentrations of the element selenium in the form of selenate. In 1987, these drainage waters began to replace previous input to Kesterson Reservoir, a pond system within Kesterson National Wildlife Refuge; this substitution was completed by 1982. In the 1983 nesting season, unusual rates of deformity and death in embryos and hatchlings of wild aquatic birds occurred at the refuge and were attributed to selenium toxicosis. Features necessary for contamination to have taken place included geologic setting, climate, soil type, availability of imported irrigation water, type of irrigation, and the unique chemical properties of selenium.
AN: 1689100

                                                                   1506 of 1521  
TI: Differential thermal and thermogravimetric analysis of sediment-forming materials from Lake Ontario.
AU: Zimmermann,-G.M.; Lean,-D.R.S.; Charlton,-M.N.
AF: Wunderhornstr. 8, 8000 Munich 90, FRG
SO: CAN.-J.-FISH.-AQUAT.-SCI. 1987. vol. 44, no. 12, pp. 2216-2224
LA: English
ER: F (Freshwater)
AB: Differential thermal analysis (DTA) and thermal gravimetric analysis (TGA) are techniques for studying physical and chemical changes of materials as they are heated at a specific rate in a defined atmosphere (usually air, but oxygen or nitrogen can be used). Reactions such as oxidation, pyrolysis, evaporation, or other shifts in energy state cause the temperature of the sample to differ from the inert reference material. The record of temperature differences provides the DTA profile. With TGA, the weight of the sample is recorded as the temperature is increased. DTA and TGA of seston, sediments, and sediment trap material from Lake Ontario were generally similar to each other but were strikingly different from those of the green alga Chlorella pyrenoidosa . Coinciding with the principal weight loss of carbohydrate material, the main exothermic reaction for all lake samples began at 200-250 degree C and peaked at 345-355 degree C.
AN: 1686894

                                                                   1507 of 1521  
TI: (Tunis Lake eutrophication: The bacterial and planktonic processes.).
OT: Phenomenes bacteriens et planctoniques dans l'eutrophisation du lac de Tunis
AU: Belkhir,-M.; Aubert,-M.; Aubert,-J.; Mathonnet,-S.
AF: Inst. Natl. Sci. Tech. Oceanogr. Peche, Stn. Oceanogr., Salommboe, Tunisia
CO: 8. Colloque International d'Oceanographie Medicale, Nice (France), 9 Oct 1985
SO: PROCEEDINGS-OF-THE-8th-INTERNATIONAL-SYMPOSIUM-ON-MEDICAL-OCEANOGRAPHY,-9-12-OCTOBER-1985,-NICE-FRANCE..  ACTES-DU-8eme-COLLOQUE-INTERNATIONAL-D'-OCEANOGRAPHIE-MEDICALE,-9-12-OCTOBRE-1985,-NICE-FRANCE.- Drach,-P.;Nissenbaum,-A.;Aubert,-M.;Aubert,-J.-eds.1987. no. 85-86 pp. 39-45
ST: REV.-INT.-OCEANOGR.-MED. no. 85-86
LA: French
ER: M (Marine)
AB: This study uses the observations of colored water cycles, evolution and the variations of chemical elements. The authors try to show ecological and metabolic information towards interspecific relationships. They draw up a plan of the evolution of the eutrophication processes.
AN: 1686873

                                                                   1508 of 1521  
TI: Report of the FAO/UNEP/WHO/IOC/IAEA Meeting on the Biogeochemical Cycle of Mercury in the Mediterranean, Siena, Italy, 27-31 August 1984.
OT: Rapport de la Reunion FAO/PNUE/OMS/AIEA sur le Cycle Biogeochimique du Mercure en Mediterranee, Sienne, Italie, 27-31 aout 1984
CA: FAO, Rome (Italy)
CO: FAO/UNEP/WHO/IOC/IAEA Meet. on the Biogeochemical Cycle of Mercury in the Mediterranean, Siena (Italy), 27 Aug 1984
SO: FAO-RAPP.-PECHES. 1986. no. 325, 17 pp
NT: 29 ref. ISBN 92-5-202242-2.
RN: FAO FIRI/R325 (Fr) (FIRIR325Fr)
LA: French
ER: M (Marine)
AB: Processes regarding the distribution, behavior and fate of mercury in the marine environment are examined with respect to chemical, physical and biological characteristics and the ocean-atmosphere dynamics. Levels of mercury in the Mediterranean are discussed in particular.
AN: 1685880

                                                                   1509 of 1521  
TI: Overview of studies on the nutrient status of Lake Ontario.
AU: Lean,-D.R.S.
AF: Natl. Water Res. Inst., Canada Cent. Inland Waters, P.O. Box 5050, Burlington, Ont. L7 4A6, Canada
SO: CAN.-J.-FISH.-AQUAT.-SCI. 1987. vol. 44, no. 12, pp. 2042-2046
LA: English
ER: F (Freshwater)
AB: Balancing human demands on the environment with the overall welfare of the biosphere is one of the greatest challenges facing society today. In lakes, the limits of use and abuse are set by biogeochemical processes. This issue integrates measurements of lake physics and nutrient availability with the response of the microbial community in Lake Ontario. Such information is vital to the understanding of factors affecting the base of the food chain and relates to the phosphorus abatement programs of the past 15 yr.
AN: 1685565

                                                                   1510 of 1521  
TI: Potential heterotrophy of deep-sea sediments. Effects of pressure (test compound =  super(14)C glucose).
OT: Heterotrophie potentielle des sediments marins profonds. Effect de la pression (traceur =  super(14)C glucose)
AU: Cahet,-G.; Bianchi,-A.; Ralijaona,-C.
AF: Lab. Arago, 66650 Banyuls-sur-Mer, France
CO: Bacteriologie Marine, Marseille (France), 17-19 May 1982
SO: PROCEEDINGS-OF-THE-INTERNATIONAL-SYMPOSIUM-No.-331-ON-MARINE-BACTERIOLOGY,-CNRS,-MARSEILLE,-17-19-MAY-1982..  ACTES-DU-COLLOQUE-INTERNATIONAL-No.-331-SUR-LA-BACTERIOLOGIE-MARINE-ORGANISE-DANS-LE-CADRE-DES-COLLOQUES-INTERNATIONAUX-DU-CENTRE-NATIONAL-DE-LA-RECHERCHE-SCIENTIFIQUE-A-MARSEILLE-DU-17-AU-19-MAI-1982.- Bianchi,-A.-ed.1984. pp. 225-229
ST: COLLOQ.-INT.-CNRS. no. 331
LA: French
ER: M (Marine)
AB: Deep sediment samples from several geographical areas, incubated with  super(14)C glucose, showed strong microbial activity. Such activity, demonstrated by samples studied aboard the ship, were only considered as measurement of potential heterotrophy. Most of the time  super(14)CO sub(2) was the product of activity, but, in some cases,  super(14)C glucose was transformed in other compounds found in diverse fractions extracted by the geochemical analysis.
AN: 1659717

                                                                   1511 of 1521  
TI: Degradation of mangrove leaf litter in the St. Lucia Estuary as influenced by season and exposure.
AU: Steinke,-T.D.; Ward,-C.J.
AF: Dep. Bot., Univ. Durban-Westville, Private Bag X54001, Durban 4000, South Africa
SO: S.-AFR.-J.-BOT.-S.-AFR.-TYDSKR.-PLANTKD. 1987. vol. 53, no. 5, pp. 323-328
LA: English
ER: B (Brackish)
AB: Rates of degradation of leaves of Avicennia marina  (Forssk.) Vierh. and Bruguiera gymnorrhiza  (L.) Lam. were investigated in St Lucia Estuary in the warm and cool seasons at three positions on the shore, viz, where leaves were constantly submerged, where they were exposed only at low spring tides and where they were inundated only at high spring tides. Degradation occurred more rapidly in A. marina  than in B. gymnorrhiza  and leaves constantly submerged decomposed at a faster rate than those exposed for most of the time. Decomposition rates were consistantly lower in the cool season. The concentration of nitrogen in all leaves increased over the decomposition period, although there was decreased in total nitrogen content with rapid decomposition. This work has emphasized the importance of mangrove leaf litter as a source of, and substrate for, nutrient release.
AN: 1659325

                                                                   1512 of 1521  
TI: Bacterial degradation of organic matter in seawater: Use of biogeochemical markers.
OT: Degradation bacterienne de la matiere organique dans les eaux de mer: Approche par les marqueurs biogeochimiques
AU: Saliot,-A.; Andrie,-C.; Jullien,-D.; Lorre,-A.; Marty,-J.C.; Scribe,-P.
AF: Lab. Phys. Chim. Mar., Univ. Pierre et Marie Curie, ERA CNRS Tour 24, 4 Place Jussieu, 75230 Paris Cedex 05, France
CO: Bacteriologie Marine, Marseille (France), 17-19 May 1982
SO: PROCEEDINGS-OF-THE-INTERNATIONAL-SYMPOSIUM-No.-331-ON-MARINE-BACTERIOLOGY,-CNRS,-MARSEILLE,-17-19-MAY-1982..  ACTES-DU-COLLOQUE-INTERNATIONAL-No.-331-SUR-LA-BACTERIOLOGIE-MARINE-ORGANISE-DANS-LE-CADRE-DES-COLLOQUES-INTERNATIONAUX-DU-CENTRE-NATIONAL-DE-LA-RECHERCHE-SCIENTIFIQUE-A-MARSEILLE-DU-17-AU-19-MAI-1982.- Bianchi,-A.-ed.1984. pp. 51-56
ST: COLLOQ.-INT.-CNRS. no. 331
LA: French
ER: M (Marine)
AB: Microorganisms play a key role in the cycling of organic matter in the marine environment, particularly at specific sites such as the air-water, water-sediment and water-particulates interfaces. The total budget of organic matter can be achieved by analyses of sources, evolution and bacterial activity markers. The evolution of concepts concerning the utilization of bacterial markers will be discussed, regarding the development of structure elucidation of fatty acids in different series: saturated, unsaturated, branched and hydroxylated. Budgets of organic matter and bacterial markers (fatty acids, hydrocarbons) are presented.
AN: 1658968

                                                                   1513 of 1521  
TI: Heterotrophic microbial activity in marine Antarctic sediments.
OT: Activite microbienne heterotrophe dans les sediments marins antarctiques
AU: Tanner,-A.C.; Herbert,-R.A.
AF: British Antarct. Surv., Madingley Rd., Cambridge, UK
CO: Bacteriologie Marine, Marseille (France), 17-19 May 1982
SO: PROCEEDINGS-OF-THE-INTERNATIONAL-SYMPOSIUM-No.-331-ON-MARINE-BACTERIOLOGY,-CNRS,-MARSEILLE,-17-19-MAY-1982..  ACTES-DU-COLLOQUE-INTERNATIONAL-No.-331-SUR-LA-BACTERIOLOGIE-MARINE-ORGANISE-DANS-LE-CADRE-DES-COLLOQUES-INTERNATIONAUX-DU-CENTRE-NATIONAL-DE-LA-RECHERCHE-SCIENTIFIQUE-A-MARSEILLE-DU-17-AU-19-MAI-1982.- Bianchi,-A.-ed.1984. pp. 29-32
ST: COLLOQ.-INT.-CNRS. no. 331
LA: English
ER: M (Marine)
AB: During December and January, rates of primary production in the near-shore coastal waters of Signy Island are high. Following the collapse of the phytoplankton bloom there is little evidence that moribund phytoplankton reaches the sediment since CHN analyses of benthic sediments show very low total nitrogen (0.03%) and carbon (0.42%) with little variation on a seasonal basis. These data indicate that heterotrophic microorganisms present in the water column and surface sediments play a significant role in the mineralisation of moribund plankton. The main objective of this study was to determine the heterotrophic potential of the microbial flora in maritime Antarctic waters and surface sediments. Two approaches have been used to estimate heterotrophic activity, the first involving the determination of individual microbial populations on a seasonable basis and the second, the uptake of  super(14)C-labelled glucose and acetate by naturally occurring  bacterial populations.
AN: 1658909

                                                                   1514 of 1521  
TI: Role of sea floor organisms in oxygen consumption in the deep North Pacific Ocean.
AU: Jahnke,-R.A.; Jackson,-G.A.
AF: Skidaway Inst. Oceanogr., Savannah, GA 31416, USA
SO: NATURE. 1987. vol. 329, no. 6140, pp. 621-623
LA: English
ER: M (Marine)
AB: Here the authors present estimates of sedimentary oxygen consumption made using benthic flux and pore-water measurements extrapolated throughout the North Pacific basin as a function of water depth. Below 3 km, sea-floor respiration is a large and perhaps dominant contributor to deep-ocean metabolism. This benthic activity appears to be highly concentrated in regions adjacent to continental margins exhibiting coastal upwelling. More extensive benthic respiration measurements are needed to verify this, especially in the northern and western Pacific Ocean.
AN: 1658841

                                                                   1515 of 1521  
TI: (Evaluation of heterotrophic activity and study of parameters related to the organic carbon cycle of limnetic environments.).
OT: Stime di attivita eterotrofa e studio dei parametri inerenti al ciclo del carbonio organico negli ambienti limnici
AU: Bertoni,-R.; Callieri-Bertoni,-C.; Contesini,-M.; Torelli,-R.
SO: REPORT-ON-THE-SCIENTIFIC-ACTIVITY-OF-THE-INSTITUTE-DURING-THE-YEAR-1983..  RELAZIONE-SULL'-ATTIVITA-SCIENTIFICA-DELL'-INSTITUTO-NELL'-ANNO-1983.- Istituto-Italiano-di-Idrobiologia,-Verbania-Pallanza-Italy1984. no. 1 pp. 58-72
ST: DOC.-IST.-ITAL.-IDROBIOL. no. 1
NT: Incl. 19 ref.
LA: Italian
ER: F (Freshwater)
AB: Problems related to the methods involved in the estimation of heterotrophic activity are examined and discussed with respect to research conducted on parameters characterizing organic carbon cycles in Lake Mergozzo.
AN: 1658359

                                                                   1516 of 1521  
TI: (Preliminary studies on the distribution of metallic elements in Lake Como.).
OT: Indagine preliminare sulla distribuzione di elementi metallici nel Lago di Como
AU: Baudo,-R.; Galanti,-G.; Guilizzoni,-P.; Varini,-P.G.
SO: REPORT-ON-THE-SCIENTIFIC-ACTIVITY-OF-THE-INSTITUTE-DURING-THE-YEAR-1983..  RELAZIONE-SULL'-ATTIVITA-SCIENTIFICA-DELL'-INSTITUTO-NELL'-ANNO-1983.- Istituto-Italiano-di-Idrobiologia,-Verbania-Pallanza-Italy1984. no. 1 pp. 20-24
ST: DOC.-IST.-ITAL.-IDROBIOL. no. 1
NT: Incl. 13 ref.
LA: Italian
ER: F (Freshwater)
AB: The findings of sampling studies regarding the levels of metals in Lake Como are discussed. The aquatic macrophyte flora and their role in the recycling of metals and sedimentation are examined.
AN: 1658236

                                                                   1517 of 1521  
TI: Ammonium production in sediments inhibited with molybdate: Implications for the sources of ammonium in anoxic marine sediments.
AU: Jacobson,-M.E.; Mackin,-J.E.; Capone,-D.G.
AF: Mar. Sci. Res. Cent., State Univ. New York, Stony Brook, NY 11794, USA
SO: APPL.-ENVIRON.-MICROBIOL. 1987. vol. 53, no. 10, pp. 2435-2439
LA: English
ER: M (Marine)
AB: Ammonium production in the presence of specific inhibitors of sulfate reduction and methanogenesis was investigated in six marine sediments which differed in bulk properties and organic matter input. In all cases, little effect of the inhibitors on ammonium production was observed, although sulfate reduction was suppressed by molybdate. This gives evidence that the processes of fermentation and hydrolysis are of primary importance in ammonium generation at the sites studied. Although sulfate reduction rates may appear to ge coupled to ammonium production rates, sulfate reduction does not necessarily contribute directly to generation of ammonium in marine environments.
AN: 1649400

                                                                   1518 of 1521  
TI: Studies of nitrogen cycling with experimental benthic chamber incubations.
AU: Prieto,-M.C.; Corredor,-J.E.
AF: Dep. Mar. Sci., Univ. Puerto Rico, Mayaguez 00708, Puerto Rico
CO: 18. Meet. of the Association of Island Marine Laboratories of the Caribbean, St. James (Trinidad), 13 Aug 1984
SO: PROC.-ASSOC.-ISL.-MAR.-LAB.-CARIBB. 1984. vol. 18, p. 3
NT: Rec'd 1987. Summary only.
LA: English
ER: M (Marine)
AB: Inorganic nitrogenous compounds and the impact of cultural eutrophication were studied for a seagrass/mangrove ecosystem in southwestern Puerto Rico utilizing 1 station in a mangrove channel (CS) with houses discharging untreated wastes; and 2 reference stations (RS) with Thalassia testudinum  and sandy sediments. Benthic chamber incubations were conducted to measure exchange of nitrogenous compounds between the sediments and the overlying water. An RS upcurrent showed a slight release of NO sub(3) from the sediments. NH sub(4) concentration also increased. Both were effectively taken up by the T. testudinum) and plankton in the water column. NO sub(3) release from sediments indicates that sediments are oxygenated in the upper layer, possibly due to release of oxygen by T. testudinum). The CS had sediments with high organic content, decaying Microcoleus lyngbyaceous  and no T. testudinum . Release of NH sub(4) from the sediments and effective uptake by the plankton in the water column were documented. NO sub(3) decrease in the chamber coupled with an increase of NH sub(4) suggest that NO sub(3) is being reduced to NH sub(4) in the sediments. The down current RS showed a release of NH sub(4) from the sediments and a gradient formation in the water column due to low mixing rates.
AN: 1645387

                                                                   1519 of 1521  
TI: (Organic matter biogeochemistry in estuarine environment: Behaviour, fluxes, properties. An application to the Gironde estuary (France).).
OT: Biogeochimie de la matiere organique en milieu estuarien: Comportement, bilan, proprietes. Cas de la Gironde
AU: Etcheber,-H.
AF: Univ. Bordeaux 1, Inst. Geol. Bassin Aquitaine, 33405 Talence, France
SO: MEM.-INST.-GEOL.-BASS.-AQUITAINE. TALENCE-FRANCE-UNIV.-BORDEAUX-1,-INST.-GEOL.-BASSIN-D'-AQUITAINE 1986. no. 19, 379 pp
LA: French
ER: B (Brackish)
AB: This thesis investigates material and energy fluxes carried by rivers to the ocean. Using an original multidisciplinary approach the author studies the organic fraction (particulate organic matter, POM) of suspended matter in a macrotidal estuary--the Gironde. In the upstream region POM comes from basin slopes during winter and is essentially autochtonous from Apr. to Sep. Particles poor in OM in the center of the estuary are in the high turbidity zone and contain essentially detrital OM. Particles rich in OM are found at the mouth of the estuary where concentration of marine OM is very high, particularly during summer. Hydrology and climate are primordial factors acting on the distribution and behaviour of POM in estuaries. In the Gironde estuary, POM is an essential scavenger of trace elements (mainly Zn, Cu). Degradation processes of POM induce drastic mobilization of bound heavy metals.
AN: 1644413

                                                                   1520 of 1521  
TI: Redfield ratios, primary production, and organic carbon burial in the Baltic Sea.
AU: Shaffer,-G.
AF: Oceanogr. Inst., Univ. Gothenburg, Box 4038, 400 40 Gothenburg, Sweden
SO: DEEP-SEA-RES. 1987. vol. 34, no. 5-6, pp. 769-784
NT: Special issue: Biological effects on the chemistry of the sea.
LA: English
ER: M (Marine)
AB: The biogeochemical cycling of oxygen, phosphorus and carbon in the Baltic Sea is investigated using a natural coordinate conservation method. The mean Redfield ratio of oxygen consumption to phosphate production due to organic decomposition is found to be 159  plus or minus  6 in the Baltic proper deep water. Utilizing the C:N ratio for particulate matter in the deep water, a "best" set of Redfield ratios is found to be 159:130:14.4:1 for -O sub(2):C:N:P. Present net community production in the Baltic proper appears to be  similar to 50  plus or minus  7 g C m super(-2) y super(-1) as calculated from oxygen consumption rates and transport rates of "new" PO super(3)@)d4 super(-) into the euphotic zone. Total primary production is estimated to be  similar to 175 g C m super(-2) y super(-1), consistent with  super(14)C primary production in the Baltic proper. Also, organic carbon may be presently buried at a rate of  similar to 10 g C m super(-2) y super(-1).
AN: 1634352

                                                                   1521 of 1521  
TI: The enrichment of lagoons with organic carbon by supratidal sabkhas: Example of the Bahiret el Biban paralic complex (Tunisia).
OT: Le role des sebkhas supratidales dans l'enrichissement des lagunes en carbone organique: L'exemple du complexe paralique de la Bahiret el Biban (Tunisie)
AU: Medhioub,-K.; Chesterikoff,-A.; Perthuisot,-J.-P.
AF: Ec. Natl. Ing. Sfax (GREDOPAR), Route de la Soukra, Sfax, Tunisia
SO: J.-RECH.-OCEANOGR. 1985. vol. 10, no. 1, pp. 29-31
LA: French
ER: M (Marine)
AB: Bahiret el Biban is one of the largest Mediterranean lagoons. As a peculiar feature, it possesses supratidal sabkhas in the sedimentary piles of which waters coming from the lagoon undergo an evaporitic evolution prior to returning to the lagoon water body. These processes induce in the latter a relative enrichment with Mg and impoverisment with sulfate. The following studies of the paralic complex have shown the existence of water masses bearing high organic carbon contents. This organic carbon is, at least partly, generated within the sabkhas interstitial brines by the bacterial consumption of cyanobacterial mats which grow on their intertidal margins and are buried under recent sediments in their supratidal areas.
AN: 1627650

