Seasonal export fluxes of size-fractionated particulate derived from polonium-210: A case study in Xiamen Bay

作     者：杨伟锋 黄奕普 陈敏 邱雨生 

作者机构：Department of Oceanography Xiamen University 

出 版 物：《Chinese Journal of Oceanology and Limnology》 (中国海洋湖沼学报（英文版）)

年 卷 期：2010年第28卷第2期

页      面：379-386页

核心收录：

学科分类：070702[理学-海洋化学] 07[理学] 0707[理学-海洋科学] 

基　　金：Supported by the National Natural Science Foundation of china (Nos. 40576037, 40606022, 90411016) China Ocean Mineral Resources R & D Association (COMRA) Project (DYXM-115-01-3-04) 

主　　题：POC 210Po 210Pb thorium size fractionation 

摘      要：Size-fractionated 210Po and 210Pb, in the size fractions 0.4 μm, 2 μm and 10 μm, were examined to determine the seasonal variability of particulate fluxes in Xiamen Bay. Good correlations between 210Po and particulate organic carbon (POC) or non-Particulate Organic Matter (nPOM) suggested that 210Po can be used to trace the export fluxes of POC and nPOM. Both steady-state (SS) model and nSS model were used to evaluate fluxes of size-fractionated 210Po, results showed that nSS model was better than the SS model in coastal areas. Based on the nSS model, size-fractionated POC fluxes decreased with increasing particle size. For the particle size studied, maximum POC fluxes occurred in autumn, followed by spring, winter, and summer. Fluxes of nPOM were an order of magnitude higher than the corresponding size-fractionated POC fluxes. Differences between size-fractionated nPOM fluxes indicated that hydrodynamic conditions were the main factor regulating transportation of particulate out of the inner Bay. In winter most particulates, including 10 μm particles, were transported under the strongest hydrodynamic conditions. In contrast, only a fraction of the 2 μm particulates were transported from the inner Bay in spring. This study suggested that 210Po is a powerful tracer of seasonal particulate export in coastal seas.