Heavy metals in SPM and sediments at Hangzhou Bay, China

Hangzhou Bay lies south of the mouth of Changjiang, which is famous for the large volume of its water and sediment discharge. It is a typical trumpet-shaped estuary, situated along a mesotidal coast. Based on the water quality survey in Hangzhou Bay in June and October 1994, the paper reveals the distributions of Cu, Pb, and Cd in suspended particulate matter (SPM) and surficial sediments of Hangzhou Bay. The concentration of Cu, Pb, Cd in the bay is higher in the north than in the south, and higher in the east than in the west. The highest particulate heavy metals level is found in Nan Hui Zui. They are in agreement with the distributions of the fine-grained matter. The concentrations of heavy metals in suspended particulate matter and in surficial sediments are very similar. Heavy metals in surficial sediments have a close relationship with the bulk density. All those underline the dominance of sedimentary dynamics on the fate of particulate heavy metals in Hangzhou Bay.