湘潭金石锰矿周边土壤污染特征及生态风险评价

Pollution Characteristics and Ecological Risk Assessment of Soil in Xiangtan Jinshi Manganese Mining Area

[目的]掌握金石锰矿周边土壤重金属含量、污染程度及分布特征。[方法]对矿区周边土壤进行实地采样,并对土壤中重金属Mn、Cd、Zn、Pb、Cu、Cr和Ni含量进行分析。采用地累积指数法及潜在生态风险指数法,评价土壤中的重金属污染程度和风险。[结果]金石矿区周边土壤受到重金属不同程度的污染,重金属的污染程度从大到小依次为Mn、Cd、Zn、Pb、Cu、Cr、Ni;重金属区域污染差异较大,局部区域土壤Mn污染严重,垂向调查发现重金属污染主要集中在表层土壤;矿区周边土壤中重金属综合的潜在危害程度为"轻微-中等",Cd是潜在生态危害最大的因子。Pb和Zn、Cd和Ni有很大相关性,可能属于同源污染物。[结论]该研究可为矿区土壤重金属污染防治提供科学依据。

[Objective]The research aimed to master the content pollution degree and distribution characteristics of heavy metals in the soils in Jinshi manganese mining area.[Method]Field sampling of heavy metals in the soil around the mining area was carried out,and the contents of Mn,Cd,Zn,Pb,Cu,Cr and Ni were analyzed.The degree and risk of heavy metal pollution in soil were evaluated by land accumulation index method and potential ecological risk index method.[Result]The surrounding soil of the Jinshi mining area was polluted by heavy metals in different degrees,and the pollution degree of heavy metals was Mn,Cd,Zn,Pb,Cu,Cr,Ni in order of big to small.Heavy metal pollution varies greatly,and Mn pollution in local soil was serious.Vertical investigation showed that heavy metal pollution was mainly concentrated in surface soil.The potential harm degree of heavy metal synthesis in the surrounding soil of the mining area was“slight to moderate”,and Cd was the factor with the greatest potential ecological harm.It could be seen that Pb was highly correlated with Zn,Cd and Ni,and may be a homologous pollutant.[Conclusion]The study can provide scientific basis for the prevention and control of heavy metal pollution in agricultural land.