宝鸡市麟游县煤矿区周边农田土壤重金属污染安全评价

Safety Evaluation of Heavy Metal Pollution in the Farmland Soils Surrounding the Coal Mines Area in Linyou County of Baoji City

文章选取麟游县的北马坊煤矿、郭家河煤矿和北王煤矿为研究区域,对其周边的农田土壤进行野外采样和室内分析,测定Zn、Cr、Pb、Cu、Cd、Hg、As 7种重金属的污染状况。结果表明:测定的7种重金属元素的最大值均超过了陕西省土壤背景值和当地的土壤环境背景值。单因子污染指数评价得出,三矿区周边的土壤Hg元素的污染较严重,局部地区已经达到了重度污染;综合污染指数法评价得出,三矿区均达到了中度到重度污染水平,其中北王煤矿污染水平较高;地质累积指数法评价得出,三矿区Hg元素的累积程度属于中度污染到强污染等级,Cd元素次之。因此3矿区周边的耕地土壤已不同程度的受到重金属的污染,相关部门应该采取一定的措施治理该区的土壤。

In this paper, Beimafang coal mine, Guojiahe coal mine and Beiwang coal mine in Linyou County were selected as the study regions and field sampling and indoor analysis of the farmland soils surrounding the study regions was performed to determine the pollution status of such seven heavy metals as Zn, Cr, Pb, Cu, Cd, Hg and As. The results showed that the maximal contents of the seven heavy metals all exceeded the soil background values of Shaanxi Provincial level and local level. Evaluation of single factor contaminant index showed that Hg pollution in the surrounding soils was serious and some local area was heavily polluted by Hg. Evaluation of comprehensive contaminant index indicated that these three coal mine regions were in moderate pollution and pollution level of Beiwang coal mine was the highest. Evaluation of geological cumulative index showed that accumulation levels of Hg in the three regions were from moderate pollution to heavy pollution, followed by those of Cd. Therefore, the farmland soils surrounding the study regions were polluted by heavy metals at various degrees and certain measures should be taken by relevant administrations to control the polluted soils in the regions.