Article

Phytoplankton Calcification in a High-CO2 World

National Oceanography Centre, Southampton, University of Southampton Waterfront Campus, European Way, Southampton SO14 3ZH, UK.
Science (Impact Factor: 31.48). 05/2008; 320(5874):336-40. DOI: 10.1126/science.1154122
Source: PubMed

ABSTRACT Ocean acidification in response to rising atmospheric CO2 partial pressures is widely expected to reduce calcification by marine organisms. From the mid-Mesozoic, coccolithophores
have been major calcium carbonate producers in the world's oceans, today accounting for about a third of the total marine
CaCO3 production. Here, we present laboratory evidence that calcification and net primary production in the coccolithophore species
Emiliania huxleyi are significantly increased by high CO2 partial pressures. Field evidence from the deep ocean is consistent with these laboratory conclusions, indicating that over
the past 220 years there has been a 40% increase in average coccolith mass. Our findings show that coccolithophores are already
responding and will probably continue to respond to rising atmospheric CO2 partial pressures, which has important implications for biogeochemical modeling of future oceans and climate.

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