湖南锡矿山锑矿区农用土壤锑、砷及汞的污染状况初探

Antimony, Arsenic and Mercury Polluton in Agricultural Soil of Antimony Mine Area in Xikuangshan,Hunan

通过实地采样调查和对样品进行实验室分析,研究了湖南锡矿山锑矿区采矿区、冶炼区和尾矿区附近农用土壤的锑、砷及汞的污染状况。结果表明这3个区域8个采样点的农用土壤均受到这3种重金属元素较高浓度的污染,土壤中锑、砷及汞的浓度分别为:141.92～8733.26、14.95～363.19和0.16～5.68 mg/kg,均远高于湖南土壤中这3种元素的背景值。锑与砷的平均浓度是荷兰土壤中锑、砷最大允许含量的695和2.3倍,而锑矿区农用土壤中汞的平均含量与荷兰土壤中汞最大允许含量2.2 mg/kg接近。在3个研究区域中,冶炼区的土壤中这3种元素的浓度均为最高,采矿区和尾矿区的依次减少。通过用地累积指数法评估锑矿区农用土壤中上述3种重金属污染程度发现,锑矿的开采和冶炼是矿区农用土壤受到重金属严重污染的根本原因,其中锑对土壤重金属污染的贡献最大。

A field survey and analysis of soils were conducted to investigate the pollution of antimony,arsenic and mercury in agricultural soils of antimony mine area in Xikuangshan,Hunan Province.It was found that the three heavy metals were significantly elevated in soil samples（141.92-8733.26 mg kg-1Sb、14.95-363.19 mg kg-1 As and 0.16-5.68 mg kg-1Hg）,which all exceeded their background concentrations in soils of Hunan.The average concentrations of Sb and As were 695 times and 2.3 times higher than the maximum permissible ones in the standard soil samples of Holland respectively,while the content of Hg was close to the maximum permissible one（2.2 mg kg-1） in the latter.The concentrations of the three elements in soil samples of smelting area were the highest in the mining area、smelting area and ore tailing area.Based on the assessment of the three heavy metals contaminated soil samples by the using of Index of geoaccumulation,it was indicated that smelters and mining activities were the main sources of heavy metals pollution of agricultural soils in antimony mine area and antimony pollution played the most important role in heavy metal pollution of soils.