某煤矿区土壤中重金属污染状况及风险评估

Heavy Metal Pollution Status and Risk Assessment in Soil of a Certain Coal Mining Area

为了探究山西省某煤矿区粗放式的矿业活动对矿区周边农田土壤的重金属污染状况以及种植农作物后,农作物体内的重金属含量对人类产生的不良效应,用梅花取样法选取矿区周围的土壤作为研究对象,采用电感耦合等离子体发射光谱仪测定了土壤中的Cu、Cr、Ni、Zn、Cd、Pb六种重金属含量及农田土壤中生长小白菜中重金属的含量。结果表明:土壤中六种重金属含量分别为17.8 mg/kg、48.8 mg/kg、25.2 mg/kg、65.9 mg/kg、0.3 mg/kg、19.1 mg/kg,采用单因子指数和内梅罗综合污染指数法评价该区土壤重金属污染程度,并进行土壤重金属含量分析。以山西省土壤背景值为参比,由单因子污染指数法得出:研究区土壤存在污染;内梅罗综合污染指数得出:研究区土壤达到中度污染水平。通过对小白菜各部位重金属含量监测,富集系数表明:各部位富集重金属能力大小为根>茎>叶。因此,应对调查地块采取有效的治理措施,避免重金属污染损害人体健康。

In order to explore the heavy metal pollution of the agricultural soil around the mining area caused by extensive mining activities in a coal mining area,Shanxi Province,and the adverse effects of the heavy metal content in agricultural objects on human beings after planting crops,the soil around the mining area was selected as the research object with the plum blossom sampling method,Six kinds of heavy metals such as Cu.Cr.Ni.Zn.Cd.Pb in soil and the content of heavy metals in Bok choy growing in farmland soil were measured by Inductively coupled plasma emission spectrometer.The results showed that the content of six heavy metals in the soil was 17.8 mg/kg,48.8 mg/kg,25.2 mg/kg,65.9 mg/kg,0.3 mg/kg,and 19.1 mg/kg,respectively.The single factor index and Nemero comprehensive pollution index methods were used to evaluate the degree of heavy metal pollution in the soil of this area,and the soil heavy metal content was analyzed.Using the background value of soil in Shanxi Province as a reference,using the single factor pollution index method,it was found that the soil in the study area is contaminated;The Nemero comprehensive pollution index shows that the soil in the study area has reached a moderate level of pollution.Through monitoring the content of heavy metals in various parts of Bok choy,the enrichment coefficient showed that the ability of each part to enrich heavy metals was root>stem>leaf.Therefore,effective governance measures should be taken to prevent heavy metal pollution from damaging human health on the surveyed land.