江西于都某钨矿区土壤重金属特征及生态风险评价

金属矿产资源的持续开发活动通常会导致矿区土壤重金属含量累积，厘清土壤重金属环境污染特征并评价其生态风险，可为监测土壤环境质量和预防土壤污染提供依据。选择江西于都某百年开采钨矿山，采用单因子污染指数法、内梅罗综合指数法和Hakanson潜在生态风险指数法，对其周边土壤中Cr、Ni、Cu、Zn、Cd、Pb、As、Hg污染特征及潜在生态风险进行调查评价。评价结果表明，研究区土壤受到Cu、Zn、Cd、Pb、As等重金属的污染，单因子污染指数分别为6.74、3.72、45.1、3.36、8.88；综合污染评价表明，Cd是主要污染贡献因子，其次为As、Cu、Pb、Zn；土壤综合潜在生态风险指数平均值高达2065，属很强生态风险；强生态风险及以上区域主要分布在矿山周边及矿山下游河道附近，分布面积约占研究区总面积的43.89%；研究区土壤重金属相关性分析表明，Cu、Zn、Cd、Pb之间具有显著的相关性。综合研究结果可知，该区域土壤Cd具有一定的潜在生态风险，应引起充分重视，矿山开发利用可能是导致Cu、Zn、Cd、Pb污染的主要原因。

Characteristics and ecological risk of soil heavy metals of a Tungsten mine in Yudu,Jiangxi Province

The accumulation of heavy metals in soil is generally originated from the persistent exploitation in the mining area, thus clarifying the environmental pollution characteristics of heavy metals in soil and evaluating the ecological risk can provide a basis for monitoring soil environmental quality and preventing soil pollution. A tungsten mine with history of a hundred years in Yudu of southern Jiangxi Province was selected as a case study. Based on the assaying data, single-factor index and Nemerow multifactor index methods were used to assess the quality of soil, then the potential ecological risks of the eight heavy metals were evaluated by Hakanson potential ecological risk index method. The evaluation results show that the single-factor pollution index of Cu, Zn, Cd, Pb and As are 6.74, 3.72, 45.1, 3.36, 8.88, respectively. Cd contributes most to the Nemerow composite pollution index, followed by As, Cu, Pb, and Zn. The average value of the comprehensive potential ecological risk index reaches up to 2065, indicating strong potential hazard. The areas with strong potential heavy metals ecological risk account for 43.89%, which are mainly distributed around mines and their downstream near the river. Correlation analysis of soil heavy metals in the study area shows that Cu, Zn, Cd and Pb are significantly correlated. In conclusion, Cd has a certain potential ecological risk and should be paid more attention, and mineral exploitation activities may be the primary cause of Cu, Zn, Cd, and Pb pollution.