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

“该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。海洋是全球最大的人为CO2汇，由于海水pH值的降低，海洋表面化学平衡和元素循环发生了大规模变化。海洋碳酸盐化学中与CO2相关的变化影响了生物过程，包括光合作用和钙化。 因此，钙化浮游植物物种可能对海洋二氧化碳浓度的变化特别敏感。 这些生物矿物反过来又影响团聚体的形成速率和性质，延缓有机质的微生物降解，从而对有机质的循环和输出起着重要作用。 来自斯托尼布鲁克的纽约州立大学的研究人员正在研究海洋颗粒聚集的过程及其对海洋酸化的敏感性。通过对培养的浮游植物进行实验室测试，科学家们的目标是了解可能导致未来海洋沉积和化学物质输出变化的机制，并考虑聚集的性质。这项研究的结果将为海水pH值下降如何影响海洋生物泵提供重要的新见解。 该项目是德国和美国科学家和研究生之间的合作努力。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."ABSTRACTOCE-0850904The 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.