吕梁市某焦化厂及周边土壤重金属污染状况与评价

Pollution Status and Assessment on Soil Heavy Metals of a Coking Plant Site and the Surrounding Farmland in LvLiang

为研究吕梁某焦化厂及周边土壤重金属的污染状况,在焦化厂内和周边农田共采集了60个土壤表层（0～20cm）样品,检测分析样品中重金属元素的含量,并采用单因子污染指数法和内梅罗污染指数法对其污染状况进行了评价.结果表明：厂区内土壤重金属Zn、Cd、Cu、Mn、Hg、As的平均含量分别为62.91 mg·kg-1、0.37 mg·kg-1、46.26 mg· kg-1、429.98mg· kg-1、0.16 mg· kg-1、11.60 mg· kg-1,厂区周边农田土壤重金属的平均含量分别为53.57 mg·kg-1、0.24 mg·kg-1、37.99 mg· kg-1、362.23mg· kg-1、0.11 mg·kg-1、11.74 mg·kg-1,厂区周边农田土壤中各重金属含量均小于厂区内土壤.除Zn和Mn外焦化厂内和周边农田土壤中的Cd、Cu、Hg、As平均含量均高于山西省土壤环境背景值.单因子污染指数法和内梅罗污染指数法评价结果表明,除5％的样品中土壤Cd含量超过了国家二级标准,属轻微污染,其余为未污染,土壤都属清洁水平;以山西背景值为评价标准各重金属都有不同程度的污染,说明该研究区土壤有重金属污染风险.

Sixty surface soil samples（0～20 cm） collected from a coking plant and the surrounding farming to study the pollution of heavy metals and a certain coking plant.The Single-factor pollution index method and Nemerow comprehensive pollution index method were also analyzed.The results showed that the concentrations of Zn、Cd、Cu、Mn、Hg、As of surface soil in site and the surrounding farmland were 62.91 mg · kg-1、0.37 mg · kg-1、46.26 mg · kg-1429.98mg· kg-1、0.16 mg · kg-1、11.60 mg· kg-1 and 53.57 mg · kg-1、0.24 mg · kg-1、37.99 mg · kg-1、362.23 mg · kg-1 、0.11 mg · kg-1 、11.74 mg · kg-1 respectively.Most of the elements of heavy metals exceed background value in soil environments in Shanxi province except Zn and Mn.The Single-factor pollution index method and Nemerow comprehensive pollution index method demonstrated that it was lightly polluted except 5 ％ Cd element had exceed the national average leverals of soil environmental quality standard;Each heavy metals have different degrees of pollution take the background value in Shanxi province as a standard,show that could have a risk of pollution on heavy metals.