
Title:  METADATA FOR PRIMARY PRODUCTION DATA SETS FROM PUMP CASTS
	COLUMBIA RIVER LMER PROJECT

Contact: Lawrence F. Small
	College of Oceanic and Atmospheric Sciences
	Oregon State University 
	Corvallis, OR  97331-5503  USA
	email: smalll@ccmail.orst.edu

Principle Investigators (Institution) and research area: 
	Fredrick Prahl (Oregon St. Univ. Oceanic and Atmospheric Science)	geochemistry;
	Lawrence Small (Oregon St. Univ. Oceanic and Atmospheric Science)	phytoplankton

Data Description: Estuarine turbidity maxima (ETM) are hypothesized to be sites of enhanced biological 
activity and chemical transformations.  An active microbial loop and enhanced copepod grazing relative to 
surrounding areas may lead to rapid regeneration of nutrients capable of fueling primary production.  
Production and its associated biochemical parameters can be used to map the ETM and determine the 
riverine versus marine contributions to ETM particulate matter. 

Spatial and Temporal Resolution: Pump cast sampling, and associated CTD casts took place from a fixed 
vessel during one 28-35 day cruise per year in 1990, 1991, 1992, 1995, and 1996.  In 1997 there were 2 
week cruies in May, July, and October.

Methodology:
	Pump casts were conducted immediately following a CTD cast and are, thus, cross-referenced by 
CTD data parameters.  Water was sampled from surface and near-bottom depths and assayed for 
chlorophyll-a and phaeophytin-a by standard fluorometric techniques.  Primary production was estimated by 
standard 14C methods.  During these incubations, fluorescence was measured before and after treatemnt 
with DCMU to estimate photosynthetic potential of the cells.  Particulate organic carbon and nitrogen were 
measured from filtered surface and bottom water samples, total suspended particulate matter was 
determined gravimetrically.  See Small and Morgan (1994) for details and further references on methods.

Variables:
	Code		cast-specific code number (see below)
	Date		date in MM/DD/YY format
	Time		Time of day (Pacific Standard Time)
	Depth		depth in meters
	Salinity	salinity
	Fluor		chlorophyll a (mg/m^3) determined by fluorometer (1992 only)
	AC3chla		chlorophyll a (mg/m^3) determined by AC-3 (see below)
	Chla		chlorophyll -a (ug / L), measured 
	Phaeo		phaeopigment (ug / L), measured
	14CProd		primary production (mg C / m^3 / h)
	DCMU		DCMU index 
	POC		particulate organic carbon (mg / L)
	PN		particulate nitrogen (mg / L)

Explanation of Code:
	Format of code is:  YYBSENN
		
		YY	first two digits indicate year
		B	letter(s) indicates boundary location or tidal series as follows: U=upstream 
(beyond salt wedge), D=downstream (below estuarine turbidity maximum), N=neap tide, S=spring tide, 
SN=spring-neap transition, E= ebb, F=flood, L=long time series, YB=Young's Bay, CB=Cathlamet Bay
		S	number of sample series at that location/tidal stage
		E	event number (sequence) within that series (an 'E' or 'F' may follow this number 
indicating and ebb or flood tide sampling
		NN	two (or three) digits indicate CTD cast number that corresponds to the pump cast
		*	an asterisk after the code indicates CTD data taken from the downcast 
immediately prior to the pump cast

Other data notes:
	*** the AC-3 unit was used beginning in 1995; data sets from before then do not contain this 
column The voltage reading from the AC-3 is transformed into a chlorophyll a value using the factory 
calibration coefficients.  The voltage signal is proportional to chlorophyll absorption after light passage 
through a series of filters contained within the AC-3 unit.

	*** DCMU index is calculated as: [F(DCMU) - F(INITIAL)] / F(DCMU), where F(DCMU) is the 
DCMU-enhanced fluorescence of the whole water sample and F(INITIAL) is the fluorescence before 
DCMU addition.

File format: comma-delineated ASCII with header;
	maximum number of records = 912;
	number of data columns = 12

References:

Small, LF and SR Morgan. 1994. Phytoplankton attributes of the turbidity maximum of the Columbia River 
Estuary, USA. In: KR Dyer and RJ Orth, eds., Changes in fluxes in estuaries: Implications from science to 
management (ECSA22/ERF, Plymouth, September 1992). pp 465-472.  Olsen and Olsen, Fredensborg, 
Denmark.
 

---------------------------------------------------------------------------------------------------------------------------------




