Clams as CO2 generators: The Potamocorbula amurensis example in San Francisco Bay

Limnology and Oceanography
By: , and 



Respiration and calcium carbonate production by the invasive Asian clam, Potamocorbula amurensis, were calculated to assess their importance as CO2 sources in northern San Francisco Bay. Production, calculated using monthly population density and size structure measured at three sites over 7 yr and a shell length/CaCO3 conversion factor, averaged 221(±184)g CaCO3 m−2yr−1. Net calcium carbonate production by this exotic bivalve releases CO2 at a mean rate of 18(±17)g C m−2yr−1. Respiration by P. amurensis, estimated from secondary production, releases additional CO2 at a mean rate of 37(±34)g C m−2yr−1. Therefore, total net CO2 production by P. amurensis averages 55(±51)g C m−2yr−1 in an estuarine domain where net primary production consumes only 20g inorganic C m−2yr−1. CO2 production by P. amurensis in northern San Francisco Bay is an underestimate of the total CO2 supply from the calcified zoobenthic communities of San Francisco Bay, and results from other studies have suggested that this rate is not unusual for temperate estuaries. Global extrapolation yields a gross CO2 production rate in the world's estuaries of 1x1014g C yr−1, which suggests that calcified benthic organisms in estuaries generate CO2 equal in magnitude to the CO2 emissions from the world's lakes or from planetary volcanism (the net source is determined by the highly variable rate of CO2 consumption by carbonate dissolution). This biogenic CO2 source is increasing because of the continuing global translocation of mollusks and their successful colonization of new habitats.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Clams as CO2 generators: The Potamocorbula amurensis example in San Francisco Bay
Series title Limnology and Oceanography
DOI 10.4319/lo.2003.48.6.2086
Volume 48
Issue 6
Year Published 2003
Language English
Publisher American Society of Limnology and Oceanography
Contributing office(s) San Francisco Bay-Delta, Pacific Regional Director's Office
Description 7 p.
First page 2086
Last page 2092
Country United States
State California
Other Geospatial Northern San Francisco Bay
Online Only (Y/N) N
Additional Online Files (Y/N) N
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