渤海中南部表层沉积物中汞的分布及风险评估

本文以渤海中南部表层沉积物为研究对象，采用DMA-80测汞仪测定表层沉积物中Hg的含量，并对其空间分布状况以及生态风险进行论述。结果表明，渤海中南部表层沉积物Hg含量范围为19.5×10-9~106.8×10-9，均值为41.5×10-9，除一个沉积物站位外，其余均高于渤海沉积物Hg的背景含量。Hg含量高值区主要分布在黄河口、渤海中部泥质区和辽东浅滩局部海域，低值区位于渤中浅滩和渤海海峡南部海域，这与河流输入、沉积物粒度以及区域矿物背景有关。应用潜在生态危害指数法对渤海中南部表层沉积物Hg的生态风险进行评价，发现72.7%的站位处于中等风险水平，13.6%的站位处于重度风险水平。

Distribution and risk assessment of mercury in surface sediments from central and southern part of Bohai Sea

Mercury contents in surface sediments from central and southern part of Bohai Sea were measured using DMA-80 mercury analyzer and then distributions and ecological risk were evaluated further. The results indicated that concentrations of mercury were between 19.5×10-9 and 106.8×10-9 and average value was 41.5×10-9. Hg contents were all over background level of Bohai Sea except one station. The higher concentration stations were mainly distributed in the Yellow River estuary, muddy areas in the central Bohai Sea, and part of Liaodong shallow shoals, While the lower contents area were mainly in the Southern of Bohai Strait and Bozhong shallow shoal. The potential ecological risk index method was used to evaluate the ecological risk of total mercury in surface sediment. The results showed that 72.7 percent of the samples could be rated moderate potential risk grade and 13.6 percent of the samples were rated serious potential ecological risk grade.