多种评价方法应用于天津核桃主产区的土壤环境质量评价  

The evaluation of soil environmental quality of main walnut producing areas based onvarious methods of heavy metal contamination assessment in Tianjin

作　　者：谢薇[1] 杨耀栋[1] 侯佳渝 菅桂芹 李国成 赵新华 XIE Wei;YANG Yao-Dong;HOU Jia-Yu;JIAN Gui-Qin;LI Guo-Cheng;ZHAO Xin-Hua(Tianjin Geological Mineral Test Center,Tianjin 300191,China;Geological Center of Tianjin Planning and Natural Resources Bureau,Tianjin 300042,China)

机构地区：[1]天津市地质矿产测试中心,天津300191 [2]天津市规划和自然资源局地质事务中心,天津300042

出　　处：《物探与化探》2021年第1期207-214,共8页Geophysical and Geochemical Exploration

基　　金：天津市财政资金项目“富硒土地地球化学特征及开发潜力研究”。

摘　　要：以天津市核桃主产区土壤和核桃为研究对象,分析了土壤重金属元素Cd、Hg、Pb、As、Cr、Zn和Cu的含量特征,选用内梅罗指数法、地累积指数法和污染负荷指数法等3种方法评价了土壤环境质量,并分析了核桃食用安全性。结果表明:研究区土壤样品中Cd、Hg、Pb、As、Cr、Zn和Cu的平均含量分别为0.19×10-6、0.06×10-6、24.1×10-6、11.9×10-6、75.5×10-6、78.9×10-6和30.6×10-6,Cd、Hg和As平均值均超过了天津市背景值,而且Cd和Cu分别有11.7%和1.7%的样品点位超过风险筛选值。根据内梅罗综合指数法可以得出,研究区土壤环境质量总体较好,但由地累积指数与污染负荷指数评价发现,研究区存在人为原因引起的土壤重金属积累情况,且污染点位均匀分布于研究区。核桃样品中Cd、Hg、Pb、As和Cr平均含量分别为0.003×10-6、0.004×10-6、0.044×10-6、0.043×10-6和0.760×10-6,均满足食品安全标准要求。In this study,the soil and walnut samples were taken in the main walnut producing area of Tianjin,and the content characteristics of heavy metals Cd,Hg,Pb,As,Cr,Zn and Cu in the soil were analyzed.Three methods were used to evaluate soil environmental quality in the study area,i.e.,Nemerow index method,geo-accumulation index method and pollution load index.The safety of walnut samples was analyzed.The results show that the average values of Cd,Hg,Pb,As,Cr,Zn and Cu in the soil samples are 0.19×10-6,0.06×10-6,24.1×10-6,11.9×10-6,75.5×10-6,78.9×10-6 and 30.6×10-6,respectively.The average values of Cd,Hg,As and Cu exceed the background values of Tianjin,and 11.7%and 1.7%of the samples of Cd and Cu exceed the risk screening values.For the single evaluation results,Nemerow single index method shows that 10.0%of the samples of Cd have slight pollution,1.7%of the samples have moderate pollution,and 1.7%of the samples of Cu have slight pollution.According to the method of Nemerow comprehensive index,the soil environmental quality of the study area is generally better,but according to the evaluation results of geo-accumulation index and pollution load index,it can be found that there is heavy metal accumulation caused by human factors in the study area,and the pollution points are evenly distributed in the study area.The average values of Cd,Hg,Pb,As and Cr in walnut samples are 0.003×10-6,0.004×10-6,0.044×10-6,0.043×10-6 and 0.760×10-6,respectively,which meet the requirements of food safety standards.

关 键 词：核桃主产区 重金属 土壤环境质量 评价方法 天津 

分 类 号：P632[天文地球—地质矿产勘探]