淮南煤矿区土壤重金属污染分布特征及污染溯源研究

摘要

为了研究矿区内土壤中重金属的污染溯源及分布特征，文章以淮南矿区为例，分别采集了在淮南矿区内新庄孜矿、潘一矿和顾桥矿3个矿区周边47个表层土壤样品，运用内梅罗综合指数法对重金属污染程度进行评价，并应用地累积指数法进行对比验证，探讨主要污染元素的污染溯源及分布特征。结果表明：2种方法获得的指数评价结果基本一致，考虑到土壤背景值具有地区差异性，所以以淮南地区土壤背景值为标准的内梅罗指数法的评价结果的参考性更大。矿区受到了以As、Cd为主要污染元素的重金属污染，As的综合污染指数从大到小排序为新庄孜矿＞潘一矿＞顾桥矿；Cd的污染指数从大到小排序为顾桥矿＞潘一矿＞新庄孜矿。综合考虑水文气象、地表径流以及煤矿开采量、开采工艺等条件，煤矿设计生产能力和实际开采产量是影响土壤Cd污染的主要因素，而As污染主要是由于煤矿长期进行采矿作业在土壤中严重累积以及矿山开采的伴生矿所导致。污染物的水平分布特征表明，污染物含量并不随距离煤矸石堆的距离远近而有规律地变化，煤矸石的露天堆放对矿区附近土壤的影响并不明显。%In order to research the distribution characteristics and pollution source of heavy metal pollu‐tion in soil in the mining area ,47 surface soil samples around the Xinzhuangzi Mine ,Panyi Mine and Guqiao Mine in Huainan mining area are collected .The extent of heavy metal contamination is evalua‐ted by using the Nemero index method ,and compared by using the geo‐accumulation index method . The distribution characteristics and pollution source of the main pollutants are analyzed .The result shows that the index evaluation results of two methods are basically consistent ,considering the soil background value with regional differences ,the evaluation result of the Nemero index method w hich uses the soil background values in Huainan area as the standard is more referenceable than the other one .The As and Cd are the main pollutants of heavy metal pollution in soil in mining area .The com‐prehensive pollution index of As in Xinzhuangzi Mine is the highest ,followed by Panyi Mine and Gu‐qiao Mine ,and the index of Cd in Guqiao Mine is the highest ,followed by Panyi Mine and Xinzhuang‐zi Mine .Considering the conditions of hydrology and meteorology ,surface runoff ,the amount of coal mining and mining technology ,it can be proved that the coal production capacity and actual production yield is the main factor for the pollution of Cd ,while the pollution of As mainly results from the seri‐ous accumulation caused by the long‐term mining and smelting of coal mine .The horizontal distribu‐tion characteristics of pollutants show that the content of pollutants does not regularly change with the increasing distance of the coal gangue .T he effect of coal gangue piled up in the open air on the soil nearby the mining area is not obvious .