【摘要】 针对陕西某钼矿区不同区域进行土壤样品采集,利用单因子污染指数、内梅罗综合指数和潜在生态风险指数法进行土壤污染评价与分析。结果表明:钼矿区周边土壤重金属Zn浓度最大,Cu、Zn变异系数分别为151. 75%、137. 85%,属于高等变异;土壤Cu污染最为严重,重度污染率达30. 00%;矿坑下游河岸区域(Q2)和露天采矿区域(Q4)土壤综合潜在生态风险指数分别为323. 84和382. 24,为强潜在生态风险,周边农田区域为轻微潜在生态风险;研究区土壤各重金属潜在生态风险存在一定的差异性,其中Cd和Hg具有极强的潜在生态风险;土壤重金属污染在Q2、生活区域(Q3)和Q4区域内应重点防控,其中Cu、Zn、Cd和As的危害应引起重视。今后应加强矿产开采生产活动中的生态环境管控,避免和降低重金属污染转移;同时,钼矿区及周边区域整体上土壤重金属潜在生态风险可控,后期需进一步加强重点区域的环境风险监测。更多还原

【Abstract】 Soil samples were collected from different sites in a molybdenum ore area in Shaanxi Province. Method of single factor pollution index, Nemerow index and potential ecological risk index were used for soil pollution evaluation and analysis. The results showed that the concentration of Zn was the highest among all heavy metals around the molybdenum ore district. The variation coefficients of Cu and Zn were 151. 75% and 137. 85%respectively, which belonged to higher variation. Pollution of Cu was the most serious in the soil, as the serious pollution rate reached 30. 00%. Comprehensive potential ecological risk index of soil in the downstream river of mine( Q2) and the open-air ore area( Q4) were 323. 84 and 382. 24 respectively, which belonged to strong ecological risk, while the ecological risk degree in the surrounding farmland was slight. There existed difference among the potential ecological risk of soil heavy metals in the study area. Among all heavy metals, Cd and Hg had potential ecological risk with extremely high strength. Q2, Q3 and Q4 zones should be a key control area for soil heavy metal pollution prevention and control, and the harmful effects of Cu, Zn, Cd and As should be taken seriously. Therefore, it is necessary to strengthen the ecological environment control of mineral mining and production activities in the future to avoid and reduce the transfer of heavy metal pollution. Meantime, the potential ecological risk of soil heavy metal was controllable in the molybdenum ore area and the surrounding area, and the environmental risk monitoring in key areas should be further strengthened.更多还原