【摘要】 在距离灌渠不同距离的包气带中钻孔取样,测定了33个土壤样品中的pH值和Ba、Cr、Cu、Fe、Mn、Ni、Pb、Zn、土壤有机质的质量分数,对这8种重金属元素在土壤样品中的质量分数进行数据统计和空间分析。结果显示:①重金属元素Cr、Cu、Ni、Pb和Zn主要来源于污水,Fe、Mn和Ba除来源于污水外,还有一部分来源于土壤母质;②Cu、Cr、Pb、Zn和Ni的空间分布差异大,变异系数可达75.22%,主要富集表层0~0.3 m深度处和黏土层(黏土层起始深度在1.2~1.5 m,厚度>40 cm)中,Fe、Mn和Ba在垂向上主要呈平均分布,空间分布的变异系数为19.09%~33.10%;③包气带中重金属元素平均含量超过当地土壤背景值的3~8倍,已经在包气带表层0~0.3 m深度处和黏土层中积累,而且Ba、Cu、Fe、Mn、Ni、Zn等重金属元素已经迁移到潜水层。更多还原

【Abstract】 Thirty three soil samples of sewage irrigation area were collected from four sites with different distances from the irrigation channels in unsaturated zone,and analyzed for pH and concentration of Ba,Cr,Cu,Fe,Mn,Ni,Pb,Zn and SOM.The spatial distribution and correlations of soil heavy metal elements were studied using SPASS.The results indicate that(1) Cr,Cu,Ni,Pb and Zn mainly come from same source,sewage,In addition to their source from sewage,Fe,Mn and Ba are also from the material of soil.(2) The coefficient of variation of Cu,Cr,Pb,Zn and Ni amounts up to 75.22%,which are mainly enriched in the surface of 0-0.3 m and the clay layer(the initial depth of clay layer is 1.2-1.5 m,thickness> 40cm).Fe,Mn and Ba show a average distribution in different depths,with their coefficient of variation is 19.09%-33.10%.(3)The content of heavy metal elements in the unsaturated zone of the study area is 3-8 times more than the soil background content.The heavy metal element have accumulated in surface of 0-0.3 m and the clay layer of 1.2-1.5 m.The groundwater is polluted by Ba,Cu,Fe,Mn,Ni and Zn.更多还原