辽东湾河口底质重金属环境地球化学

Environmental geochemistry of heavy metals in bottom sediments of the river mouths in Liaodong Bay

对辽东湾诸河口底质样进行了Pb、Zn、Cu、Cd等含量分析。辽东湾底质重金属污染物主要是Cd、Zn、Pb,尤其是Cd平均含量为1.16mg/kg,超过土壤环境质量三级标准;Zn平均含量为105.28mg/kg,超过土壤环境质量一级标准。运用地累积指数法对其污染程度评价,认为辽东湾西北及北部河口底质污染严重,葫芦岛市五里河桥下>大凌河口北>辽河口>双台子河口等处。与历史资料的对比表明,4种重金属的平均含量均有所提高。

The content of cadmium, lead, copper and zinc in the bottom sediments of the river mouths in Liaodong Bay were quantitatively analyzed. Cd, Pb and Zn are the main heavy metal pollutants. The average content of Cd in the sediments of the most river mouths reaches 1.16 mg/kg, which exceeds the standard of Class Ⅲ of the soil environment quality. The average content of Zn is 105.28 mg/kg, which exceeds the standard of Class I of the soil environment quality. The degree of pollution is estimated by the geoaccumulation index, and the results show that the pollution is more serious on northwestern and northern river mouths of Liaodong Bay. The sequence of degree of pollution is as follows: Wuli River in Huludao City > the north estuary of Daling River > estuary of Liaohe River > estuary of Shuangtaizi River. Comparing with the historic data, the average contents of the four kinds of heavy metal increased.