The trend and extent of heavy metal accumulation over last one hundred years in the Liaodong Bay, China

An integrated analysis has been carried out on two cores dated by combination of 210Pb and 137Cs in order to characterize the extent of heavy metal accumulation in the Liaodong Bay, Northern China. The concentrations and burial fluxes of Zn, Pb, Cd, and Hg increased abruptly after late 1970s. The enrichment factors of Cd, Hg, Zn and Pb are more than 30, 10, 7, and 3.5, respectively, in the surface sediments. Coincident to the increase of heavy metal contents, the decreasing trend of 206Pb/207Pb ratio indicated lead in the surface sediments mainly come from anthropogenic activities.