东昌湖水体和表层沉积物重金属元素污染评价

Pollution Evaluation of Heavy Metal Element of Water and Surface Sediment in the Dongchang Lake

通过对东昌湖水体重金属元素(Cr、Cu、Zn、As、Pb)及表层沉积物中重金属元素(Cr、Cu、Zn、As、Pb、Ni、Cd)含量的测定,采用基于国家地表水质量标准(GB3838-2002)评价、水体综合污染评价法对东昌湖水体重金属污染状况进行评价,结果表明,水体重金属元素的含量均达到国家Ⅰ类水质标准,水质良好。同全国主要湖泊的表层沉积物重金属含量进行对比,并采用国家土壤环境质量标准(GB15618-95)、潜在生态风险指数法以及地累积指数法对东昌湖表层沉积物重金属元素的污染状况进行评价,结果表明:东昌湖表层沉积物主要以Cd污染为主。东昌湖水体和表层沉积物重金属污染状况主要是有关部门对东昌湖的环境治理、东昌湖现有排污情况以及重金属元素自身地球化学特征等几个方面综合作用的结果。

Based on data of heavy metal elements in water（Cr, Cu, Zn, As, Se and Pb） and surface sedi-ments（Cr, Cu, Zn, As, Pb, Ni and Cd） recovered from the Dongchang Lake, the pollution of the water had been assessed using criterion of sediments quality standard （GB3838-2002） and synthetically pollution index. The results showdd that the average concentrations of heavy metals of water did not exceed the standards of ClassⅠ of environmental quality standard for surface water in China, and the quality of water was good. Comparing the content of heavy metals in surface sediments with the main lakes of China and using criterion of sediments quality standard, potential ecological risk indices and index of geoaccumula-tion, the author assessed the pollution of surface sediments and found the main heavy metal element of surface sediments＇ pollution is Cd in the Dongchang Lake. The pollution of water and surface sediment in Dongchang Lake is the result of the combined effects of environmentgovernance, existing sewerage system and geochemical characteristics of heavy metal element.