淮河流域某镇农业土壤重金属含量特征及污染评价

通过野外采样和实验室分析，对淮河流域某镇农业土壤中Cd，Cr，Cu，Ni，Pb和Zn等六种重金属的含量特征进行了研究，并利用富集因子法、地累积指数法和潜在生态风险指数法对各种重金属的污染状况进行了评价。结果表明，研究区农田土壤中Cd和Cu的质量分数平均值分别为0.113 5和22.09 mg·kg-1，超过了安徽省土壤重金属背景值0.097和20.4 mg·kg-1，其余四种重金属的平均值均未超过安徽省土壤重金属背景值。地累积指数法和潜在生态风险指数法的评价结果一致表明，研究区域土壤中六种重金属污染程度最强的为重金属Cd，部分采样点土壤中的Cd对于生态系统存在轻微的风险，其他五种重金属均未对采样点生态系统造成风险。整个研究区域土壤属于轻度综合潜在生态风险程度。

Analysis of Heavy Metals Distribution Characteristics and Pollution Assessment in Agricultural Region Soils of Huaihe Basin

By means of field sampling and laboratory analysis, the content distribution characteristics of Cd, Cr, Cu, Ni, Pb and Zn in agricultural region soils of Huaihe basin in Anhui province were analyzed. Assessment of heavy metal pollutions was conducted using enrichment factor, geoaccumulation index and potential ecological risk index. The results showed that the average mass fraction of Cd and Cu was 0.113 5 and 22.09 mg·kg-1 respectively in the study area soil, which were above the background values 0.097 and 20.4 mg·kg-1 in Anhui Province. The average mass fraction of other four heavy metals did not exceed the average values of Anhui Province. The results of the evaluations from geoaccumulation index and ecological risk assessment discovered that Cd is the strongest pollution metal among six heavy metals in the study area soil. For some samples of the study soil, Cd was slight risk for the ecosystem. The ecosystem risks caused by the other five heavy metals were not obviously for the sampling points. The entire study area soils were mid integrated potential ecological risk.