渤海湾海河大沽口表层沉积物中重金属的污染特点

采用U．S．EPA-3051方法测定了渤海湾海河大沽口表层沉积物中Cd、Pb、Zn、As、Cr、Mn、Ni和Cu等8种重金属元素的含量，并分析其污染水平及分布特点。结果表明，Cu和As是大沽口表层沉积物中主要的污染元素，其含量均高于渤海湾环境背景值，其它重金属元素含量与环境背景值相当，但所测元素均未超过海洋沉积物质量标准（GB18668—2002）第三类限定值。Cu的最大值65．57mg／kg出现在B10点，高于环境背景值2．5倍，Pb和Cd的含量在B6点也高于环境背景值，表明河口地区或靠近海岸的沉积物更容易受到来自陆源污染物的影响。

Characteristics of heavy metal pollution in surficial sediment of Dagu estuary in Bohai Bay

The concentrations of heavy metals （Cd, Pb, Zn, As, Cr, Mn, Ni, Cu） in the surficial sediments collected from Dagu estuary of Bohai Bay were determined with U. S. EPA-3051 method to evaluate pollution status and distribution. The results showed that Cu and As were considered as the major heavy metal pollutants in the surficial sediments, which were higher than the regional environmental background values. But they did not exceed the grade-three marine sediment quality of China （GB18668-2002）. The highest Cu concentration （65.57 mg/kg） was found at site BIO, which was about 2.5 times higher than that of the environmental background value. The concentrations of Pb and Cd at site B6 were also higher than the environmental background values. These results indicated that the sediments in the estuary and the adjacent sea area were polluted by land- sourced pollutants.