某铀矿区农田土壤重金属生物有效性分析  

Analysis of Bioavailability of Heavy Metals in Farmland Soil in Uranium Mining Area

作　　者：代鹏飞 王帅[1] 钱坤 袁凤辉[1] 朱业安[1] 黄德娟[1,2] DAI Peng-fei;WANG Shuai;QIAN Kun;YUAN Feng-hui;ZHU Ye-an;HUANG De-juan(Key Laboratory of Nuclear Resources and Environment(East China University of Technology),Ministry of Education,Nanchang 330013,China;College of Nuclear Science and Engineering,East China University of Technology,Nanchang 330013,China)

机构地区：[1]核资源与环境教育部重点实验室(东华理工大学),江西南昌330013 [2]东华理工大学核科学与工程学院,江西南昌330013

出　　处：《生态与农村环境学报》2021年第5期644-650,共7页Journal of Ecology and Rural Environment

基　　金：国家自然科学基金(41867063,41361088)。

摘　　要：为探究某铀矿区附近农田土壤的重金属生物有效性,以该铀矿采矿区、冶炼厂和尾矿坝附近农田土壤为研究对象,分析土壤理化性质并采用经改良后的BCR四步提取法对土壤重金属Pb、Cd、Cr、Cu和U生物有效性进行评估。结果表明:研究区农田土壤偏酸性;不同区位农田土壤有机质含量由大到小依次为尾矿坝、冶炼厂和采矿区;重金属赋存形态主要为残渣态;重金属元素Pb、Cd、Cr和Cu生物有效态含量分别占其总含量的27%~42%,放射性核素U生物有效态含量为U总含量的43%~45%;不同区位农作物对重金属Cr、Cd、Cu和Pb富集系数由大到小依次为采矿区、冶炼厂和尾矿坝;各区位农作物对U的富集效果均最强。综上,研究区农田土壤重金属生物有效性受pH值、有机质含量及重金属生物有效态含量等因素的综合影响,重金属生物有效性越强,其引起的生态风险越大;不同区位农田土壤中重金属Cr、Cd、Cu和Pb生物有效性由大到小依次为采矿区、冶炼厂和尾矿坝;不同区位农田土壤重金属中U的生物有效性均最强;由于受提炼铀矿石的影响,冶炼厂相较于其他研究区域具有更强的U生物有效性;虽然尾矿坝农田农作物对重金属元素的富集效果较差,但考虑到该区位土壤重金属含量较大,其带来的生态风险仍值得关注。研究结果可为今后该矿区重金属污染的科学生物防治提供重要理论依据。In order to explore the bioavailability of heavy metals in farmland soil near a uranium mining area,the samples of farmland soil near mining area,smelter and tailings dam were collected as the research object to analyze the physical and chemical properties of the soil and the improved BCR four-step extraction method was applied to evaluate the bioavailability of the heavy metals(Pb,Cd,Cr,Cu)and U in the farmland soil.The results show that the farmland soil in the study area is acidic;the organic matter content of the farmland soil in different locations followed the order of:tailing dam>smelter>mining area;The forms of heavy metals in the farmland soil are dominated by the residue state;The content of bioavailable form of the heavy metal elements(Pb,Cd,Cr and Cu)accounted for 27%-42%of the total content of heavy metals,and the content of bioavailable form of radionuclide U was 43%-45%of the total content of U;the enrichment coefficients of heavy metals(Cr,Cd,Cu and Pb)for crops grown at different locations followed the order of:mining area>smelter>tailing dam;Compared with the adsorption of the other heavy metals,the adsorption of U by crops in all locations was the strongest.In summary,the bioavailability of heavy metals in farmland soil is comprehensively affected by factors such as pH,organic matter content,and bioavailable content of heavy metals.The stronger the bioavailability of heavy metals,the greater the ecological risk they cause;The bioavailability of the heavy metals(Cr,Cd,Cu,and Pb)in farmland soil of different locations followed the order of:mining area>smelter>tailing dam;U had the strongest bioavailability in farmland soils of different locations;due to the influence of uranium ore extraction,U in the smelter had a higher bioavailability than in other study areas.Though,the crops in the tailings dam farmland have poor enrichment effect on heavy metal elements,while considering the high content of heavy metals in the soil of this location,the ecological risks brought by it are also worthy of atten

关 键 词：铀矿区 农田土壤 重金属 赋存形态 生物有效性 

分 类 号：X53[环境科学与工程—环境工程]