遵义东南部地区农业土壤重金属分布特征及风险评价

对贵州省遵义东南部地区农业土壤重金属As、Pb、Cd、Cr、Hg污染现状进行调查和分析,结果表明,该地区重金属平均含量分别为:As 11.39mg/kg,Pb 38.75mg/kg,Cd 0.34mg/kg,Cr 40.45mg/kg,Hg0.21mg/kg。主要污染物为Cd,单项污染指数是1.13,单项生态危害系数是50.85,为中等生态危害级,遵义县污染指数最高为1.43,单项生态危害系数为64.35。同时通过污染指数与生态危害系数比较,表明Cd、Hg在构成土壤环境污染的同时,也造成了相应的生态危害。

DISTRIBUTION AND RISK EVALUATION OF HEAVY METALS IN AGRICULTURAL SOILS OF SOUTHEASTERN ZUNYI CITY,CHINA

The pollution of heavy metals(As,Pb,Cd,Cr,and Hg) in agricultural soils of Southeastern Zunyi,Guizhou Province were investigated and assessed in this paper.The results showed that the average contents of heavy metals in the soils were As 11.39mg/kg,Pb 38.75mg/kg,Cd 0.34mg/kg,Cr 40.45mg/kg,Hg 0.21mg/kg.The Cd is the main contamination element,with an average single pollution index of 1.13,and an average single ecological risk index of 50.85,showing this area is in medium ecological risk class.The highest pollution index is 1.43 in Zunyi County,with an average single ecological risk index of 64.35.The results also indicated that Cd and Hg had caused some relevant ecological risk by comparing the pollution index with the ecological risk index of heavy metals.