BIOGEOCHEMICAL CYCLES AND BIOACCUMULATION OF PB AND ZN IN JIAOZHOU BAY, CHINA
胶州湾水生系统中Pb、Zn 的分布特征及其在生物体中的浓缩

Concentrations of Pb, Zn and other environmental elements were determined in bottom waters, pore waters, sediments, and clams collected from 47 stations in the Jiaozhou Bay, Qingdao City, China in summer 2003 and 2004. The trace metals contents were the highest in surficial sediment over those in bottom water, pore water, and organisms. Bioaccumulation in clam was obvious for having factors at 36 for Pb, and 935 for Zn. Lately, the amounts of trace metals in both bottom water and sediments were mainly controlled by the proximity to the estuary, as high concentrations were generally found in estuaries. In this study, high value area of trace metals in sediment occurred mainly in the east of the Jiaozhou Bay; and high contents of the metals Pb, Zn in pore water was mainly limited in hydro-dynamically quiet area in the western front of Hongdao due to low exchange rate. However, distributions of Pb and Zn in clam are different from the above-mentioned scenario, indicating that trace metals in clams were irrelevant with metal concentrations in ambient sediment or seawater. Therefore, bioaccumulation of trace metals was not simply related with the ambient concentration, but with the chemical forms of metal in sediment or water. Regression analysis shows that pore water contributed more to the enrichment of Pb, Zn in the organism.