Abstract:Abstract:By using the total chemical concentration of the macrocomponents, microcomponents and trace metal components as well as the environmental factors, the paper discusses in detail the general biogeochemical characteristics of trace metals in different media and areal distribution of trace metals of various media in the Jiaozhou Bay and reveals the response of the aqueous system of the bay to the terrestrial material input. Viewing the aquatic system as a whole, vertically, the surface sediments are the concentration zones of all trace metals and the organisms in the system have obvious bioaccumulation effect compared to their aquatic surroundings. The bioaccumulation factors of clams are 1385 for Cu, 93 for Hg and 725 for As. Laterally, the total amount of trace metals in both bottom water and sediments are mainly controlled by the proximity to the estuary, i.e. the high concentrations are generally distributed in various main estuaries in the Jiaozhou Bay. Especially, the high value areas of trace metals in the sediments mainly occur in the east of the Jiaozhou Bay. The high content of the metal Cu in pore water is mainly restricted in hydro-dynamically quiet areas, e.g. at the frontal edge of Hongdao Island. However, the distribution pattern of the chemical field of the trace metals in organisms such as clams is not coincident with that of the above-mentioned various media, i.e. the concentrations of trace metals in organisms are not related to the concentrations of the same metal in the ambient sediments or seawaters. Therefore, the authors believe that the accumulation of a given trace metal in organisms does not simply depend on the total amount of the given metal in the ambient media, but that there is selectivity. Organisms have their own choice to accommodate trace metals. Moreover, regression analysis shows that bottom water makes an appreciable contribution to the enrichment of Cu, Hg and As in organisms.