不同方法评价喀斯特煤矿区农田土壤重金属生态风险比较  

Ecological risk assessment of heavy metals in farmland soils around karst coal mining areas:A comparison of various methods

作　　者：刘品祯[1,2] 贾亚琪 程志飞 杨珍[1] 杜启露[1] 吴迪 LIU Pinzhen;JIA Yaqi;CHENG Zhifei;YANG Zhen;DU Qilu;WU Di(Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment,Guizhou Normal University,Guiyang,Guizhou 550001,China;School of Chemistry and Chemical Engineering,Qiannan Normal University for Nationalities,Duyun,Guizhou 558000,China)

机构地区：[1]贵州师范大学贵州省山地环境信息系统与生态环境保护重点实验室,贵阳550001 [2]黔南民族师范学院化学化工学院,贵州都匀558000

出　　处：《中国岩溶》2018年第3期371-378,共8页Carsologica Sinica

基　　金：贵州省"125计划"重大科技专项;项目名称:黔产红托竹荪生态适应性及优质高产大棚立体栽培技术研究;项目合同编号:黔教合重大专项字2015[043];贵州省科技计划项目;基于碳酸钙剂量对黔产红托竹荪富集重金属及产质的机制;合同编号:黔科合LH[2016]7204号

摘　　要：采用TCLP法、内梅罗综合污染指数、嵌入I_(geo)综合污染指数法等方法对贵州织金县某煤矿区周边农田土壤重金属进行评价。土壤中Cd、Cr、Cu、Ni、Hg和Zn的含量范围分别为0.79~2.08 mg·kg^(-1)、144.20~464.40 mg·kg^(-1)、91.63~187.50 mg·kg^(-1)、48.13~104.47 mg·kg^(-1)、0.14~2.33 mg·kg^(-1)、144.35~265.89 mg·kg^(-1),所有土壤样点的Cd、Cr、Cu和Ni含量均已超过国家土壤环境质量二级标准,部分土壤样点的Hg和Zn含量超过二级标准。TCLP法评价结果所有土壤样点均未受到重金属污染;内梅罗综合污染指数法评价结果为农田土壤重金属生态风险处于安全水平;嵌入Igeo综合污染指数法评价结果表明,90%的土壤达到中度污染以上,其中65%的土壤处于中度污染,25%的土壤受到中度至重度污染;潜在生态危害指数法评价表明,所有土壤样点重金属均处于轻微生态风险水平。针对不同评价方法得出的结果存在差异的情况,在评价土壤重金属污染状况时,应根据评价目标的差异选择合适的评价方法。In this paper,we use TCLP method and the methods of Nemerow comprehensive index and geoaccumulation index(Igeo)to evaluate heavy metal pollution in the farmland soils around mining areas in Zhijin County of Guizhou province.The results show that the contents of cobalt(Cd),chromium(Cr),copper(Cu),Nickle(Ni),mercury(Hg)and arsenic(As)in the soil are in the range of 0.79~2.08 mg·kg-1,144.20~464.40 mg·kg-1,91.63~187.50 mg·kg-1,48.13~104.47 mg·kg-1,0.14~2.33 mg·kg-1,and 144.35~265.89 mg·kg-1,respectively.And all the total contents of Cd,Cr,Cu,and Ni in the soil is higher than those of the second-class standard of the national codes on soil environmental quality,while parts of the Hg and zinc contents exceed this standard.The TCLP-Nemerow composite index shows that all sampling points are at safe levels and not polluted by heavy metals.The assessment using Igeo method indicates that 65%of the sample points are at a moderate pollution level,25%of those are at moderate to severe pollution levels.The potential ecological risk index shows that all the sampling points are at a slight ecological risk level.It can be seen that the analytical results by different evaluation methods differ from each other.Practically,it its hence recommended to choose an appropriate evaluation method based on the pollution degree of the soils.

关 键 词：煤矿 土壤重金属 TCLP法 内梅罗综合污染指数 嵌入Igeo综合污染指数法 生态风险 

分 类 号：X53[环境科学与工程—环境工程] X825