Effects of ocean acidification on the formation and sinking of particle aggregates

Suny At Stony Brook, Stony Brook NY

Investigators

Abstract

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." ABSTRACT OCE-0850904 The ocean, which provides the largest global sink for anthropogenic CO2, has experienced large-scale changes in the surface ocean chemical equilibrium and elemental cycling due to decreases in seawater pH. CO2 related changes in the carbonate chemistry of the ocean affect biological processes including photosynthesis and calcification. Thus, calcifying phytoplankton species are likely to be particularly sensitive to changes in oceanic CO2 concentrations. These biogenic minerals in turn affect the formation rate and properties of aggregates and delay the microbial degradation of organic matter, thereby playing a significant role for organic matter cycling and export. Researchers from the State University of New York in Stony Brook are investigating the processes of marine particle aggregation and their sensitivity to ocean acidification. Through laboratory testing of cultured phytoplankton, the scientists aim to understand the mechanisms and consider the properties of aggregation that might most result in alterations of sedimentation and chemical export in the future ocean. Results from this research will provide important new insights on how a decrease in seawater pH could affect the biological pump of the ocean. This project is a collaborative effort between German and U.S. scientists and graduate students.