Water samples with the natural phytoplankton community are collected around the Bay.
Radioactive carbon dioxide is added to each sample to be a tracer of
the algal growth that will take place.
Photosynthetron
Sub-samples are grown in a shipboard incubator (photosynthetron) over a range of light intensities to simulate production at different depths in the water.
(Lewis and Smith 1983)
In the phytoplankton cells, carbon dioxide and water are combined by
photosynthesis to form new plant matter.
The amount of radioactivity in the newly formed plant matter is a measure of the rate of primary productivity.
The URL of this page is http://sfbay.wr.usgs.gov/access/ColeCloern/HowMeasure.html
Pages created and maintained by Laura Zink Torresan
Last modified: 2 April 1997
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