The distributions of particulate heavy metals and its indication to the transfer of sediments in the Changjiang Estuary and Hangzhou Bay, China

Particulate heavy metals (Cu, Pb, Cd) were measured following intensive sampling in June and October 1994 at 70 stations in the Changjiang Estuary and Hangzhou Bay, China. In the study area, particulate Cu and Pb have a similar level that is higher than the concentration of particulate Cd. Cu, Pb and Cd concentrations in suspended sediments are higher than those in bed load. In the middle of Hangzhou Bay, heavy metal concentrations in suspended sediments and bed load are similar. This may be the result of the frequent exchange between them, which is due to the strong dynamic condition. A negative relationship was observed between concentrations of heavy metals in bed load and bulk density. Fine-grained sediments were the main carriers of heavy metals. Sedimentary dynamics dominate the fate of heavy metals in these sites. The distributions of metals (especially Cu) in suspended sediments can indicate the transfer of sediments in this area.