葫芦岛锌厂周边土壤重金属污染状况及生态风险评价

Heavy Metal Pollution and Ecological Risk Assessment of Soil around Huludao Zinc Smelter

以葫芦岛锌厂周边地区土壤为研究对象,通过对重点区域土壤的取样分析,得到葫芦岛锌厂周边土壤中主要重金属污染物的种类和污染程度,及重金属污染物的水平、垂直分布规律图,并采用潜在生态危害指数法和地积累指数法对其污染情况进行风险评估,结果表明,葫芦岛锌厂周边土壤中主要的重金属污染物为:Cd、Hg、Zn、Cu、Ni、As,其中Zn的污染最严重;水平分布规律显示重金属污染物主要集中在锌厂四周,距离锌厂越远重金属污染程度越轻;垂直分布规律表现为表层土壤重金属含量高于下层土壤;运用潜在生态危害指数法进行评价,6种重金属的潜在生态危害由强至弱依次为:Cd>Hg>As>Cu>Zn>Ni,葫芦岛锌厂周边土壤总体处于很强生态危害;运用地积累指数法进行评价,葫芦岛锌厂周边土壤中各种重金属的污染程度由强至弱依次为:Hg>Cd>Zn>Cu>As>Ni,土壤环境总体处于中度污染.

The surrounding soil of Huludao Zinc Smelter taken as the object,the types and pollution degree of heavy metal pollutants as well as the horizontal and vertical rule,were analyzed by sampling from the key areas.Furthermore,the risk assessment of these pollutants was taken by the potential ecological risk index and geo-accumulation index.The result showed that： Cd,Hg,Zn,Cu,Ni and As were the main heavy metal pollutants in the soils.The horizontal distribution showed that the farther the heavy pollution area is from the Zinc Smelter and the lower the pollution level is.The vertical distribution indicated that content of heavy metal in topsoil was higher than that in the subsoil.The method of potential ecological risk index was shown the order of six heavy metals from strong to weak as follows： CD Hg As Cu Zn Ni.Consequently,the soil around Huludao Zinc Smelter was in a strong ecological hazard.The method of geo accumulation index evaluation was shown the order of six heavy metals from strong to weak as follows： Hg CD Zn Cu As Ni,and the soil environment at the moderate pollution.