农村水塘底泥重金属来源及潜在生态风险评价

Source and Potential Ecological Risk Assessment on Heavy Metal in Ponds Sediment from Rural Areas

对安徽泗县农村水塘底泥中7种重金属元素C r、M n、Cu、Zn、A s、Pb和F e的含量进行了实验测定及来源分析,并利用潜在生态危害指数法对底泥重金属污染的潜在生态风险进行了评价。结果表明:M n、Cu、Zn和A s的平均含量均超出安徽省土壤背景值,而C r、Pb和F e的平均含量则低于背景值;C r、F e和Pb主要来源于自然成土因素,A s和M n主要来自板材加工等企业的污染排放以及含A s养殖饲料的使用,而Cu和Zn主要来自于交通源;底泥重金属污染属于中等潜在生态危害水平,其中A s、Cu的潜在生态风险最高。

The concentrations of seven heavy metal elements（Cr,Mn,Cu,Zn,As,Pb,Fe） in ponds sediment from rural area of Sixian county of Anhui were determined,and their sources were analyzed,then the potential ecological risks of the heavy metal were assessed by potential ecological risk index.The results indicated that the mean concentrations of Mn,Cu,Zn and As in ponds sediment were higher than the value of Anhui soil background,and those of Cr,Pb and Fe were lower than background because 3 elements mainly came from natural soil forming source,and As and Mn mainly came from the contamination of wood-processing industry and the use of breeding fodder containing As,and Cu and Zn mainly came from traffic source.The potential ecological risk of the heavy metal in ponds sediment was belonged to medium level,but potential ecological risk of As,Cu was highest.