The Water Resources Division of the United States Geological Survey in Menlo Park, CA are using chlorophyll fluorometers in San Francisco Bay to provide critical data that is being used as part of the Plankton Dynamics Project. Fluorescence is a known proxy for phytoplankton biomass - the USGS utilizes moored fluorometers in San Francisco Bay and the Sacramento-San Joaquin Delta combined with underway and laboratory fluorometers to determine the abundance and productivity of planktonic microalgae in order to define and quantify some important processes:
processes that regulate population dynamics and productivity of planktonic organisms in estuaries
processes through which the plankton alter and reflect water quality in estuaries
benthic processes that affect plankton dynamics and productivity of estuaries; in addition to helping define anthropogenic impacts on estuarine ecosystems
The instrument systems they are currently using include:
One, soon to be two, permanently moored SCUFAs at the Dumbarton Bridge, South San Francisco Bay. Surface and bottom high frequency sampling - helping us understand not only total biomass of phytoplankton, but information on how blooms develop and exactly when they develop. They are presently working on radio-telemetering this data so that we can access it real time on the web.
At various times of the year, 4-10 SCUFAs moored in the Delta for 2-5 months....within flooded islands (tidal lakes). The data from these moorings help to understand if these systems function as sources or sinks of phytoplankton (primary foodsource) - currently this data is very relevant since there are plans to flood numerous tracts of land in the delta and create more of these lakes.
A 10-AU with a flowcell used in underway mode for continuous horizontal sampling during regular Bay sampling cruises.
A TD-700 Laboratory Fluorometer for chlorophyll extractions.
Author: James Cloern & Tara Schraga
Institution: United States Geological Survey, Menlo Park, California, USA