淮南矿区土壤中6种典型微量元素的空间分布特征及其生态风险评价

煤矸石在地表长时间大量堆积会释放微量元素，并迁移到周围土壤中引起污染.以淮南矿区土壤为研究对象，采集不同开采年限矿区（新庄孜矿、潘一矿和顾桥矿）土壤和矸石样品，采用电感耦合等离子体原子发射光谱（ICP-AES）测定土壤和矸石中6种元素Cd，Cr，Cu，Ni，Pb和Zn的含量，探讨微量元素的空间分布特征、污染程度和生态风险.结果表明：6种元素的含量水平横向分布趋势特征不明显，但不同开采年限矿区土壤中6种元素的含量呈现出老矿>中年矿>新矿的特点；6种元素只有Cd元素含量超过土壤背景值；单项污染指数评价表明，只有Cd元素在新庄孜矿呈现轻微污染，在潘一矿和顾桥矿呈现轻度污染；迭加指数评价表明，3个矿区的土壤污染等级均为中度污染；潜在生态风险指数评价表明，淮南矿区土壤中Cd元素具有相当大的潜在生态风险，3个矿区的土壤均具有中等生态风险.
Abstract：Accumulation of coal gangue can release trace elements into the surroundings, causing severe soil pollution. To access the soil deterioration and environmental contamination by trace elements under the coal mining activities, soil and coal gangue samples were collected from 3 different mines (Xinzhuangzi, Panyi, Guqiao) in Huainan city, Anhui Province, China. Concentrations of trace elements (Cd, Cr, Cu, Ni, Pb and Zn) were determined using an inductively coupled plasma atomic emission spectrometry (ICP-AES). The results show that Cd is the only one element that exceeded the soil background of Huainan. There are no obvious characteristics for horizontal trace metal distributions. The oldest mine presented the worst contamination for the time effect (old mine> middle aged mine> new mine). The soil pollution assessment using individual pollution index suggests that Cd presents light pollution in Xinzhuangzi Mine, and minor pollution in Panyi and Guqiao Mine. The three mines all present moderate pollution risk evaluated using superimposed indices. Potential ecological risk index indicates that Cd element poses a considerable potential ecological risk, and the soil of the three mining areas has medium ecological risk.