摘要
研究钼矿尾矿区周边菜地土壤的重金属污染现状及生态风险。选取20个钼矿尾矿区周边受污染菜地的土壤样本,用HNO3-HF-HClO4处理后,采用等离子体发射光谱仪(ICP-AES)测定土壤样品中Mo、Pb、As、Hg、Cr、Cd、Zn、Cu、Ni的全量并分析其存在形态,进行生态风险预警评估。结果表明,土壤中重金属含量的分布为残余态>有机结合态>氧化结合态>酸可提取态(Pb、Zn氧化结合态>有机结合态,Hg有机结合态=酸可提取态>氧化结合态);菜地土壤的生态风险指数IER=80.62,其预警类型为重警;主要重金属污染为Cd、Hg、Cr污染并伴有Zn、Ni、Cu污染;Hg的酸可提取态所占比例较大,可能影响农作物的正常生长;重金属污染可能来自尾矿石中重金属的释放,并与污灌及化学农药的使用有一定关系。研究为清除或减轻土壤重金属污染、修复和改良已污染土壤提供参考依据。
This paper is to study the vegetable soil＇ s ecological problems around the tailing-areas of molybdenum ore so as to make a proper ecological risk warning assessment. For our research purpose, we have chosen 20 soil samples polluted near the tailing-areas of molybdenum ore. All the samples were treated with HNO3-HF-HClO4 and let exposed to the contents of Mo, Pb, As, Hg, Cr, Cd, Zn, Cu, Ni respectively and then analyzed by ICP-AES. At the same time, we have also analyzed the concurrent forms of the heavy metals. As a result of analysis, it has been found that the ecological risk warning assessment can be quantitatively expressed in an equation form of IER = 80.62, with the heavy metal distribution forms being： residual morphology 〉 organic associated morphology 〉 oxidation associated morphology 〉 acid extractable morphology （Pb, Zn oxidation associated morphology 〉 organic associated morphology, Hg organic associated morphology = acid extractable morphology 〉 oxidation associated morphology）. Thus, it can be concluded that the pollution of the above said soils belong to the heavy degree while the soils pollution in the near-minlng areas were mainly polluted by the Cd, Hg, Cr along with Zn, Ni, and Cu. Moreover, the more remarkable existence of Hg acid extractable morphology tends to affect the growth of crops more seriously. Besides, the accumulated heavy metal release from the tailings mine, the pollution of underground water as well the overuse of chemical pesticides can also be found affecting the normal growth of the crops.
出处
《安全与环境学报》
CAS
CSCD
2008年第2期76-79,共4页
Journal of Safety and Environment
基金
教育部科学技术研究重点资助项目(03058)
辽宁省教育厅科学技术研究项目(2006032)
关键词
环境质量监测与评价
尾矿区
菜地
土壤污染
重金属污染
重金属分布形态
environmental quality monitoring and evaluation
railings area
vegetable land
soil pollution
heavy metal pollution
heavy metal form
