The Sources and Burial of Marine Organic Carbon in the Eastern China Marginal Seas

作者：Yali Cao, Rong Bi, Xingchen Wang, Xi Chen, Jingwen Hu, Yaoyao Wang, Yiqing Jiang, Hailong Zhang, Lei Xing, Meixun Zhao · 发表于：Frontiers in Marine Science · 年份：2022 · DOI：10.3389/fmars.2022.824181 · 被引用次数：23 · 研究领域：Marine and coastal ecosystems、Microbial Community Ecology and Physiology、Marine Biology and Ecology Research

The ecological functions and biogeochemical processes of continental marginal seas are important for the global carbon cycle. In the eastern China marginal seas (ECMS), phytoplankton productivity has increased significantly in recent decades, but the sources and burial processes of marine organic carbon (OC) remain under-studied. We analyzed the contents of marine lipid biomarkers (brassicasterol, dinosterol, and C 37 alkenones) in surface suspended particles obtained from seven cruises between 2010 and 2015, and in surface sediments from eight cruises between 2006 and 2012 in the ECMS, to estimate marine OC sources and burial. The correlations between lipid biomarkers and environmental factors were quantified to reveal controlling factors. The study area was divided into four regions according to cluster analysis conducted based on sediment parameters. Our results showed that the concentrations of marine lipid biomarkers in surface water were high near large estuaries such as the Changjiang River Estuary and the Yellow River Estuary, but those in surface sediments were high in mud areas. Nutrient concentration was a key factor controlling phytoplankton biomass in surface water, with high nutrients enhancing the growth of diatoms and dinoflagellates, while haptophytes were more abundant in low-nutrient, high-salinity and cold environments. High marine OC contents calculated from total OC δ 13 C were mainly associated with fine sediments transported by coastal currents, and fi...