Distribution characteristic and correlation relationship of reactive sulfur and heavy metals in sediments of Meiliang Bay and Wuli Lake of Taihu Lake
太湖梅梁湾与五里湖沉积物活性硫和重金属分布特征及相关性研究

The distribution characteristic of acid volatile sulfide (AVS), simultaneously extracted metals (SEM), and total metals were studied in the surface and core sediments of Meiliang Bay and Wuli Lake in Taihu Lake. It was found that there were similar distribution characteristics for AVS and SEM in surface sediments, and the concentration of AVS and SEM decreased from the steady deposition area of estuary to the centre of the bay (lake). The ratio of AVS/SEM was < 1 in the surface sediments, indicating that heavy metals in surface sediment might have potential bioavailability. The concentration of AVS increased with sediment depth, followed by decrease with large variation, while the concentration of SEM remained constant. Though comparing the concentration of SEM with total metals, it was shown that the extracted Cu and Ni decreased with sediment depth, indicating that increasing association of Cu and Ni with sulphides in deeper sediment layer, while the lower extracted ratios for Pb and Zn compared with sulfidic sediment illustrated that the AVS should not have a strong controlling on sediment Pb and Zn. From the molar ratio of AVS and reactive iron, it is known that the heavy metals were rather dynamic and active in sediments of studied sites.