【作者】 王建波；

【导师】 张海霞；

【作者基本信息】 兰州大学 ， 化学工程， 2011， 硕士

【摘要】 土壤重金属化学行为和环境质量的研究是土壤圈物质循环研究的重要组成部分。近年来,随着城市化和工业化的快速发展,重金属污染延伸到越来越多的地方。特别是重金属在土壤中具有积累性和迁移性,直接或间接地危害城市生态环境以及人类的健康。西固区是兰州市重点工业区,也是多数高污染企业所在地,对该地区重金属污染的研究更显重要。本论文通过对西固区兰州铝厂周围的土壤重金属的分布、形态的研究,旨在全面评估重污染企业土壤重金属的现状及其潜在的生态效应。土壤重金属分布分析结果表明,重金属Co、Cu、Mn、Ni、Pb、Zn、Cr污染严重,其中,Mn的含量已严重超标,Pb污染程度较轻。各重金属的含量随样品采集半径的增加而减少,因此可以推测重金属污染与铝厂的生产活动有很大关系。各金属的形态分析结果表明,重金属污染主要以残渣态为主,Cd、Mn和Cr的弱酸态占有较大的比例,容易通过植物吸收而进入人类的食物链,需要引起极大关注。其中Cd的生态风险性最高。更多还原

【Abstract】 Heavy metals in soils have been received increasing attention due to potential environmental and ecological consequences primarily. In recent years, heavy metal pollution in soil has been detected in more and more locations. Because of accumulation and migration, heavy metals in soil ether directly or indirectly harm the urban environment and human health. Xigu, a district of Lanzhou, is a primary industrial district, where lots of enterprises caused severe environmental pollution. Study on heavy metals pollution of Xigu District appears to be more and more important. This study is sought to assess the current status of heavy metals around of Lanzhou Aluminum Plant in Xigu District by investigations of their contents, speciation and potential risk assessment.The result from the distribution of heavy metals showed that the pollution of seven elements (Co、Cu、Mn、Ni、Pb、Zn、Cr) is the most serious, especially Mn. Pb caused low-level pollution. Content of all heavy metals in the soil decreases with the collection radius increasing, indicating the impact of production activities of Aluminium Plant related to the soil formation on the distribution of heavy metals. The result from speciation analysis of the heavy metals showed that all heavy metals exist in residual fraction in the soil. Cd, Mn and Cr exist in weak acid fraction and represent a major component. We should arouse great concern of Cd, Mn and Cr which are absorbed by plants easily. The ecological risk of Cd is the highest.更多还原