沱湖保护区周边土壤-水稻重金属地球化学特征OA

To investigate the distribution characteristics and enrichment patterns of heavy metals in rice and root soils around Tuo Lake Nature Reserve,this article collected 8 rice samples and 8 root soil samples from the work area,and tested and analyzed the content and pH characteristics of 5 heavy metals including As,Cd,Cr,Pb,Hg in the samples;the characteristics of heavy metals in the study area were evaluated by using methods such as correla-tion analysis,ground accumulation index(Igeo),pollution load index(PLI),and biological enrichment coefficient method(BCF).The research results indicate that:The farmland soil around Tu Lake Nature Reserve is in a weakly acidic environment,and the heavy metal content is affected by human activities.The average values of As,Pb,and Hg in the root soil exceed the background values,but the content of all five heavy metals are below the risk screen-ing values.The maximum content of five heavy metals in rice is below the pollution limit,indicating that there is no overall health risk to the crops.The ground accumulation index indicates that there is only one mildly polluted point of As in the root soil of the study area,and it is generally in a clean state.The pollution load index indicates that 50%of the root soil in the study area is in a non-polluted state.The iological enrichment coefficient evaluation shows that there is a significant difference in the absorption and enrichment ability of heavy metals by rice in the study area(The BCF value is 0.000 3～0.931 9),with the strongest absorption and enrichment of Cd element.The correlation analysis results indicate that the sources of As,Cd,Cr,Hg,and Pb in rice may be different from those in root soil,and soil pH has a significant impact on the absorption and enrichment of heavy metal Cd by rice.The re-sults of this study can provide data support for understanding the occurrence status of heavy metals in farmland a-round Tuo Lake Nature Reserve and pollution prevention and control.