长寿地区土壤重金属元素污染特征及评价

Assessment of Heavy Metal Pollution of Soil in the Changshou Region

为查明长寿城区及周边区域表层土壤中As、Cd、Hg等8个重金属元素的污染情况,进行土壤测量结果显示,区内Cr、Hg、Ni等大部分元素的平均含量高于三峡库区深层土壤背景值,Hg、Pb的后期叠加作用最为强烈;除Hg外,其余7个元素含量间存在显著正相关,其中Cr、Ni最为显著;随着p H值增加,Ni、Cr、Cd、Cu含量显著增加;单因子污染指数评价和内梅罗综合指数评价均显示研究区内土壤环境质量总体较好,污染区域较少,以轻度污染-中度污染为主,重污染约占全区面积的0.3%,Hg元素为研究区内最主要的污染元素。

Pedogeochemical survey indicates that average contents of 8 heavy metal elements such as Cr, Hg, Ni, etc. in Changshou and its,neighborhood are higher than the deep soil background values in the Three Gorges Reservoir Region, and later superposition of Hg, Pb is obvious. With the exception of Hg, the remaining seven elements, especially Cr and Ni, are in notable positive correlation. Contents of Ni, Cr, Cd and Cu increase with pH value. Single factor pollution index assessment and N. L. Nemerow comprehensive index assessment show that soil in the study area is subjected to light and moderate pollution with area of heavily pollution accounts for about 0.3% of the whole area. Hg is principal pollution element.