Does the benthos control phytoplankton biomass in South San Francisco Bay?

James E. Cloern

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USGS · 70156387

Does the benthos control phytoplankton biomass in South San Francisco Bay?

James E. Cloern

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Abstract

South San Francisco Bay, USA, is a shallow coastal embayment that receives large inputs of nutrients (N. P, Si) and small local inputs of freshwater. Phytoplankton dynamics are typically characterized by a spring bloom when surface chlorophyll a increases from < 5 to > 40 mg m -3 . The bloom persists for 2 to 4 wk, and then dissipates. Phytoplankton biomass remains low (chlorophyll a < 5 mg m -3 ) from May through December, although light and nutrient availability are sufficient to sustain growth rates of 1 to 1.5 divisions d -1 in the expansive shallows. Transport processes apparently exert a small influence on phytoplankton biomass, and calculated zooplankton grazing accounts for only a small reduction in net rate of phytoplankton population growth in the shallows. However, suspension-feeding bivalves are sufficiently abundant to filter a volume equivalent to the volume of South Bay at least once daily. These observations suggest that grazing by benthos is the primary mechanism controlling phytoplankton biomass during summer and fall.

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Marine Ecology Progress Series Article

Source-reported bounding extent: 37.41270958119496° to 37.76420119453823° latitude; -122.40829467773436° to -121.90155029296875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

James E. Cloern. 1982. Does the benthos control phytoplankton biomass in South San Francisco Bay?. https://pubs.usgs.gov/publication/70156387

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