# Genovesa Crater Lake, Galapagos 400 Year Nitrogen and Carbon Isotope Data #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #----------------------------------------------------------------------- # # NOTE: Please cite original publication, online resource and date accessed when using this data. # If there is no publication information, please cite Investigator, title, online resource and date accessed. # # Description/Documentation lines begin with # # Data lines have no # # # Online_Resource: https://www.ncdc.noaa.gov/paleo/study/19466 # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/ecuador/galapagos/genovesa2015gu1.txt # # Archive: Paleolimnology # # Parameter_Keywords: geochemistry, carbon isotopes #--------------------------------------- # Contribution_Date # Date: 2015-11-06 #--------------------------------------- # Title # Study_Name: Genovesa Crater Lake, Galapagos 400 Year Nitrogen and Carbon Isotope Data #--------------------------------------- # Investigators # Investigators: Conroy, J.L.; Thompson, D.M.; Collins, A.; Overpeck, J.T.; Bush, M.B.; Cole, J.E.; Anderson, D.J. #--------------------------------------- # Description and Notes # Description: Sediment nitrogen (d15N) and carbon (d13C) isotope record from Genovesa Crater Lake, Galapagos for the past 400 years. # Provided Keywords: #--------------------------------------- # Publication # Authors: Jessica L. Conroy, Aaron F. Collins, Jonathan T. Overpeck, Mark B. Bush, Julia E. Cole and David J. Anderson # Published_Date_or_Year: 2015-09-28 # Published_Title: A 400-year isotopic record of seabird response to eastern tropical Pacific productivity # Journal_Name: Geo Geography and Environment # Volume: # Issue: # Pages: # Online_Resource: http://onlinelibrary.wiley.com/doi/10.1002/geo2.11/abstract # Report Number: # DOI: 10.1002/geo2.11 # Abstract: Seabirds play an important role in coastal environments, serving as key indicators of marine ecosystem variability as well as biovectors that influence terrestrial productivity and carbon storage. Long-term estimates of seabird populations remain rare, but lakes that support large seabird populations in their watersheds can archive a history of seabird activity in their sediment records. Here we present a seabird guano-influenced sediment record from Genovesa Crater Lake, Galapagos Islands, home to the world's largest reported colony of red-footed boobies (Sula sula) and smaller populations of other species. Influx of seabird guano into Genovesa Crater Lake produces high sedimentary d15N values, and temporal variability in sediment d15N primarily reflects changes in guano influx through time. Two abrupt increases in sedimentary d15N occurred at 1835 AD and 1965 AD, and variance increased following the 1965 AD shift. The largest of these abrupt shifts at 1835 AD coincided, within age model error, with an abrupt increase in marine productivity indicators in sediment records off the coast of Peru and Chile. In the latter part of the twentieth century, d15N values increased during periods of higher landings of Peruvian anchoveta and sardines. We hypothesise that seabird presence and activity on Genovesa increased during periods of higher regional marine productivity. Enhanced variance in Genovesa d15N following the 1965 AD shift may reflect a modern population more susceptible to climate and environmental variability than at any other time in the last 400 years. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: NSF-RAPID-1256970, NSF-0957881 #--------------------------------------- # Funding_Agency # Funding_Agency_Name: US National Oceanic and Atmospheric Administration # Grant: NA07OAR4310058 #--------------------------------------- # Site Information # Site_Name: Genovesa Crater Lake # Location: Ocean>Pacific Ocean>Eastern Pacific Ocean>Galapagos Islands # Country: Ecuador # Northernmost_Latitude: 0.33 # Southernmost_Latitude: 0.33 # Easternmost_Longitude: -89.96 # Westernmost_Longitude: -89.96 # Elevation: 0 m #--------------------------------------- # Data_Collection # Collection_Name: Genovesa2015GU1 # First_Year: 1605 # Last_Year: 1907 # Time_Unit: AD # Core_Length: # Notes: #------------------ # Chronology_Information # Chronology: # Radiocarbon Ages # core Sample Description Depth (cm rel GU-6) Lab number d13C (per mil) FMC 14C age (years) cal yrs error 1s # GU-6 210Pb 0.9 -51.4 8.1 # GU-6 210Pb 2.3 -48.9 8.4 # GU-6 210Pb 3.0 -46.1 8.9 # GU-6 210Pb 4.1 -37.9 10.8 # GU-6 210Pb 4.9 -28.4 13.5 # GU-6 210Pb 6.4 -25.7 13.8 # GU-6 210Pb 7.9 -14.5 17.9 # GU-6 137Cs 7.9 -13.0 1.0 # GU-6 210Pb 9.4 -10.0 19.6 # GU-6 210Pb 10.9 4.7 29.5 # GU-6 210Pb 12.4 9.4 30.5 # GU-6 210Pb 13.9 23.8 39.0 # GU-6 210Pb 15.4 30.4 35.6 # GU-7 mangrove leaf 47 AA66663 -23.3 0.9646+/-0.0045 289+/-38 # GU-7 mangrove leaf 52 AA91765 -25 0.9608+/-0.0054 321+/-45 # GU-7 mangrove leaf 54 AA66664 -23.6 0.9407+/-0.0045 491+/-39 # #--------------------------------------- # Variables # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # ## depth_cm depth, , , cm, , , , ,N ## age_AD age,,,year AD,,,,,N ## corg% Organic carbon percent,sediment,,%,,Paleolimnology,,elemental analysis,N ## N% Nitrogen total percent abundance, sediment,,%,,Paleolimnology,,elemental analysis,N ## d13CborgVPDB delta13C bulk organic,sediment,,per mil VPDB,,Paleolimnology, Suess corrected composite,isotope ratio mass spectrometry,N ## d15Norg delta15N organic,sediment,,per mil air,,Paleolimnology,,isotope ratio mass spectrometry,N # #------------------------ # Data # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Value: # depth_cm age_AD corg% N% d13CborgVPDB d15Norg 0.0 1907.5 12.24 1.09 -12.66 19.79 0.5 1902.3 11.33 0.92 18.89 1.0 1897.3 11.91 0.95 -13.26 18.72 1.5 1892.7 12.00 0.87 -14.37 19.41 2.0 1888.3 8.94 0.74 -13.96 19.90 2.5 1884 10.35 0.89 -12.50 20.79 3.0 1879.8 9.33 0.84 -13.79 19.30 3.5 1875.5 11.72 0.92 -14.56 20.34 4.0 1871 11.21 0.91 -12.45 20.00 4.5 1865.3 11.01 0.89 20.42 5.0 1859.7 10.11 0.87 -14.56 19.13 5.5 1854.1 10.10 0.89 -14.76 19.80 6.0 1848.4 10.40 0.87 -13.66 21.26 6.5 1843 11.70 0.97 -13.69 20.85 7.0 1837.7 10.14 0.84 -12.25 21.97 7.5 1832.7 9.79 0.75 -12.9 15.3 8.0 1827.6 9.59 0.71 -11.8 14.4 8.5 1822.6 9.83 0.76 -12.9 14.0 9.0 1817.5 8.11 0.69 -13.1 14.4 9.5 1811.7 8.13 0.69 -12.2 14.7 10.0 1805.9 8.38 0.75 -13.5 14.7 10.5 1800.2 10.33 0.75 -12.6 14.3 11.0 1794.5 10.60 0.84 -12.3 15.6 11.5 1788.6 7.57 0.57 -12.4 14.9 12.0 1782.7 9.79 0.78 -13.7 15.5 12.5 1777 10.09 0.81 -13.4 16.3 13.0 1771.5 8.25 0.76 -12.2 16.4 13.5 1766.2 9.18 0.75 -12.5 13.7 14.0 1760.8 8.54 0.65 -13.9 11.7 14.5 1755.1 8.41 0.72 -12.2 13.7 15.0 1749.1 8.17 0.70 -13.8 12.1 15.5 1742.8 8.52 0.63 -12.6 13.0 16.0 1736.5 9.35 0.67 -14.0 11.9 16.5 1730.1 9.82 0.75 -15.4 11.7 17.0 1723.8 8.94 0.67 -13.3 12.6 17.5 1717.9 9.44 0.79 -14.1 13.5 18.0 1712.1 8.88 0.69 -13.8 12.9 18.5 1706.3 8.04 0.62 -14.1 12.1 19.0 1700.6 9.47 0.67 -13.5 12.1 19.5 1694.7 9.18 0.64 -13.6 11.3 20.0 1688.9 8.41 0.66 -13.5 11.8 20.5 1683.3 9.08 0.69 -13.2 12.3 21.0 1677.6 9.87 0.77 -13.0 13.4 21.5 1671.4 8.45 0.65 -13.4 11.5 22.0 1665.2 9.15 0.72 -12.9 13.1 22.5 1659.1 10.14 0.79 -13.1 12.1 23.0 1653 11.25 0.82 -13.0 12.3 23.5 1647.2 10.29 0.73 -14.1 12.3 24.0 1641.4 9.30 0.67 -13.1 13.1 24.5 1635.4 10.12 0.80 -14.4 14.1 25.0 1629.4 10.26 0.78 -12.4 13.4 25.5 1623.6 10.37 0.69 -14.2 12.3 26.0 1617.7 10.90 0.65 -14.6 12.7 26.5 1611.4 11.03 0.71 -15.0 13.3 27.0 1605.1 11.38 0.96 -15.8 13.3