中文摘要：

土壤中重金属污染是主要环境问题之一，对土壤重金属形态进行研究可以为铀矿山污染土壤进行科学的修复提供可靠依据，并可为土壤污染物防治和管理奠定基础。选取某铀矿山尾矿坝下游4个表层土壤样品，对土壤中重金属元素Cd、Pb、Zn和放射性重金属U的化学形态分布进行了研究。结果表明：该铀矿山尾矿坝下游表层土壤中Cd化学形态主要为可交换态和碳酸盐结合态，具有很强的生物活性和可迁移性；Pb、Zn的化学形态则主要为残渣态，生物有效性较差；U主要分布在铁锰氧化物结合态，对生态系统具有一定的潜在危害。

英文摘要：

Heavy metal pollution of soil is one of the major environment issues. The study of the form of heavy metals in soil can provide a reliable base for a scientific restoration of the soil polluted by uranium mines and lay a foundation for the control and management of soil pollutants. Four surface soil samples were taken from the area downstream of the tailing dam of a uranium mine and the chemical form distribution of the heavy metals in the soil such as Cd, Pb, Zn and radioactive U was studied. The result indicates that the Cd in the soil occurs mainly in exchangeable phase and carbonate phase that have strong biological activity and migration. Pb and Zn occur mainly in residual phase that has a poor bioavailability. U occurs mainly in association with Fe-Mn oxidation phase that has certain potential harzard to the ecosystem.