有色金属矿区土壤Pb、Zn、Cd污染评价及形态分布研究

A Study of Pollution Assessment and Speciation Distribution for Pb,Zn,Cd in Soil of Nonferrous Metal Mining Areas

以郴州废弃矿区土壤为研究对象,对矿区所采集的12个土壤样品进行重金属含量调查及综合污染程度分析,并采用地累积指数法对重金属污染程度进行评价。结果表明,土样中重金属Pb、Zn、Cd的平均含量分别为:3 149.36 mg/kg、3 848.75 mg/kg、26.74 mg/kg。Zn和Cd达到极严重污染程度,Pb达到强污染严重水平。采用BCR连续提取法对土壤中Pb、Zn、Cd三种重金属元素的形态进行分析,结果表明Pb主要以可还原态存在,Zn主要以残渣态存在,Cd主要以弱酸提取态存在。

With soil of discarded mining areas in Chenzhou as research object, investigation was carried on heavy metal content and comprehensive pollution degree of twelve soil in the area, geostatistics and multistatistics were applied to evaluate pollution degree of heavy metals. The results indicate that average concentrations of Pb, Zn and Cd were 3149.36,3848.75,26.74 mg.kg-1, respectively. The soil was extremely seriously polluted by Zn and Cd, and seriously polluted by Pb. The results of BCR sequential extraction procedure show that Pb was dominated by reducible form, while Zn and Cd were dominated by residual formand weak acid extracive form respectively.