万山汞矿区土壤重金属污染特征及来源解析

以万山汞矿区土壤为研究对象,采用电感耦合等离子体质谱仪和原子荧光光谱仪测定土壤中的重金属含量,分别运用内梅罗综合污染指数（NPI）法和潜在生态风险指数（RI）法评价土壤重金属污染和潜在生态风险,并应用相关性分析、主成分分析和聚类分析对土壤重金属来源进行分析。结果表明：土壤Hg、Cd、As、Pb、Cu、Ni和Zn出现不同程度累积,分别达贵州省背景值的263.61、2.31、1.28、2.11、1.70、1.01和3.52倍;土壤重金属平均NPI为188.00,属于严重污染水平,Hg是主要污染因子;土壤重金属平均RI为10 655.70,属于极强潜在生态风险水平,Hg是主要潜在生态风险因子;土壤中Cu、Ni、Cr主要源于自然活动,As、Pb、Zn主要源于燃煤和交通运输污染,Cd主要源于农业污染,Hg主要源于汞冶炼污染。

Characteristics and source of heavy metals in contaminated soil in Wanshan mercury mine area

Taking the soil in Wanshan mercury mine area as the research object,the contents of heavy metals in the soil were determined using inductively coupled plasma mass spectrometer and atomic fluorescence spectrophotometer. Nemerow comprehensive pollution index （NPI） and potential ecological risk index （RI） were used to evaluate soil heavy metal pollution level and potential ecological risks,respectively. Correlation analysis,principal component factor analysis and cluster analysis were used to identify the sources of heavy metals in soil. The results show thatof Hg,Cd,As,Pb,Cu,Ni,and Zn accumulates in soil in varying degrees,and the concentration is 263.61,2.31,1.28,2.11,1.70,1.01 and 3.52 times of the soil background value of Guizhou Province,respectively;The average NPI is 188.00,which represents a serious pollution,with Hg being the most crucial pollution factor;The average RI is 10 655.70,which represents a extremely strong potential ecological risk,with Hg being the most crucial potential ecological risk factors;Cr,Ni and Cu mainly come from natural activities,As,Pb and Zn mainly come from coal and traffic pollution,Cd mainly comes from agricultural activities,and Hg mainly comes from mercury smelting pollution.