粤西黄铁矿区铊-铅污染土壤的环境质量研究

Environmental Quality of Soil Polluted by Thallium and Lead in Pyrite Deposit Area of Western Guangdong Province

以云浮硫铁矿开采场和尾渣堆放区为研究对象,采用HNO3-H2O2-HClO4-HF混酸-微波消解处理土壤样品,运用电感耦合等离子体质谱(ICP-MS)测定土壤样品中重金属的含量,研究了开采场附近土壤表层、尾渣堆放区土壤剖面的铊、铅、镍、铜、锌、镉等毒害重金属的含量。结果表明,云浮硫铁矿开采活动给矿区土壤环境带来了严重的危害。与中国土壤环境背景值相比,土壤中重金属含量最高可为背景值的35倍。运用Muller地积指数对土壤重金属污染现状进行了系统的环境风险评估,证实目前云浮矿区土壤中存在不同程度的铊、铅、铜、锌、镉等毒害重金属污染,其中,铊、铅的污染最为严重,镉、锌等达到中度污染至强污染,且污染已经渗透至土壤深层,特别是毒害性极强的重金属铊,生态环境受到严重危害。

The environmental quality of soil polluted by heavy metals, such as thallium, lead, nickel, copper, zinc, cadmium et al, in pyrite deposit area of west Guangdong Province were studied. The soil samples were treated HNO3-H2O2-HClO4-HF with microwave digestion, then the heavy metals were determined by ICP-MS. It was found mining activities in the Yunfu area had caused severe environmental changes. The concentration of heavy metals in the soil in pyrite deposit area was 35 times higher than that of the average background of soil in China respectively. Using geo-accumulation index developed by Muller, it was found that pyrite deposit area in western Guangdong province is polluted by five elements; The soil was seriously polluted by thallium and lead with middle or light polluted by copper, zinc, nickel, cadmium et al. And the result on the soil profiles showed that the contaminations had infiltrated into lower layer soil, in particular thallium, ecological environmental was harmed severely.