Bioavailability of Pb, Zn, Cd and Cr Bioaccumulation in Clam from Aquatic Ecosystem in the Jiaozhou Bay
Pb、Zn、Cd和Cr等元素的生物有效性研究——以胶州湾水生系统为例

In this aquatic ecosystem study, bottom water, sediments, pore water, and clam were sampled for trace metals analysis. The authors probed into the relationships of trace metals in aquatic ecosystems and the bioaccumulation of Pb, Zn, Cd and Cr in clam in relation to their respective concentrations in the pore water. Moreover, the speciation of Pb, Zn, Cd and Cr in the pore water was simulated by the software PHREEQC. The results reveal that PbCO-3, Zn 2 , CdCl-2 and Cr(OH)-3 are dominant species in the pore water. The bioavailable species, however, are PbSO-4, ZnOHCl, CdCl and Cr(OH) -2. It is concluded that the trace metal bioaccumulations in aquatic ecosystems are essentially controlled by the concentrations of bioavailable species rather than by the total concentrations of trace metals or the contents of their dominant species.