| Estuarine and coastal areas, which interact actively for ocean and land, respond sensitively for natural processes and human activities. There are good connections within living space, survival quality of human and social continuable development and environment evolvement of these areas. In sediments of these areas, the distribution and geochemistry characteristic of heavy metals are influenced directly by depositional environment.In this paper, 4 sea areas of Xiamen seas, which have complex hydrodynamic feature and landform were investigated. Basing on the data of grain size analysis of surficial sediment and core sediment, the spatial distribution and morphological analysis of heavy metals in the sediments, concentrations of TOC and AVS, environmental quality valuation et al., we analyzed the depositional environment of different sea areas. The variety of depositional environment was reappeared by analysis of the sediment cores. The environmental Geochemistry characteristic of heavy metals was discussed. The pollution level of the main heavy metal elements was impersonality appraised. The results of this investigation were just as follows: The depositional environment in different sea area, different station in the same sea area of Xiamen seas was analyzed in full. On the base of granularity of the typical core sediment, the variation of modern depositional environment of the four sea areas in Xiamen seas were discussed.According as content and distribution characteristics of Cu, Zn, Pb, Cd, Cr, Hg and Arsenic, and a rather large difference of sediment composition in different station, the enrichment components of each element in surface sediment were acquired by multi-analytical method.It is found that the content of Zn, Cu, Pb, Arsenic and Cr in fine gravel and in coarse sand could reflect their background value. Which offer a more handy means for analyzing and judging the man-made pollution of these elements. The speciation analysis of the elements Cu, Zn, Pb, Cd, Cr and Arsenic was carried out among the surface sediment in different sea areas, different stations. The content of heavy metals unsteady states reflected different influence of anthropogenic factors among different sea areas, different stations of the same sea area.The variation of depositional environment, influence of anthropogenic factors and pollution history of heavy metals in Xiamen seas were reviewed objectively, according to the vertical distribution of heavy metals and grain size analysis of the sediment cores. It is found that since 1930s, a rather large variation of hydrodynamic feature and depositional environment in the Xiamen West Harbour was found. The depositional environment was different distinctly, grain size composition of the sediment was stable relatively, hydrodynamic became weak, sediment source was concentrated relatively, especially after the Gaoji sea wall was built (1956a). On the whole, the highest polluted period was 1947~1990. Since 1990s, the pollution levels appeared lighten trend. For the sediment, the more stable of the source, smaller of the grain size, better of the separation, then the content of heavy metals in sediment was higher. There was markedly positive correlation between the concentrations of the most heavy metals and the concentration of organic carbon and sulfide. For the influence of point source pollution, there was not evidence correlativity among one or two element of heavy metal, organic carbon and sulfide.The pollution degree of heavy metals in surface sediment was appraised fully and impersonality. As a synthesis point of appraising views, there was different pollution degree of Cu, Zn, Pb and Arsenic in different sea areas, different station of the Xiamen seas. The element of Cu has elevated concentrations in Xiamen West Harbour, and should be paid more attention. At the same time, it was found that for the element Cd, it did not fit to appraise by the ratio of secondary phase and primary phase. As a result of that, need more investigation.
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