农田土壤重金属生态风险区划分

目的基于Hakanson潜在生态风险评价结果,探索应用指示克里格方法进行农田土壤重金属污染风险区的多级划分的可行性。方法对研究区内均匀选取的463个土壤采样点的5种重金属元素Pb、Cd、As、Cr和Hg,采用Hakanson潜在生态危害指数评价研究区的土壤重金属的潜在生态风险,依据评价结果设定阈值参数,运用指示克里格方法绘制有明显污染趋势的各土壤重金属元素(Cd和Hg)在各级潜在生态风险评价标准值下的污染风险区和各级区域综合土壤重金属潜在生态风险评价标准值下的污染风险区,实现农田土壤重金属污染风险区的多级划分。结果验证结果的误判率介于0.45%~26.94%之间,为可接受范围。结论本研究所采用的方法可用于农田土壤重金属污染风险区划分,为土壤污染修复提供科学依据。

Division of soil heavy metal ecological risk region of farmland

Objective The feasibility of multi division of soil heavy metal ecological risk region of farmland by using the indicator kriging was explored based on the results of potential ecological risk assessment invented by Hakanson. Methods The potential ecological risks of Hg, Cd, As, Cr and Pb in soils of the 463 sampling points of study area were evaluated firstly. According to the evaluation results, threshold parameters were set. Pollution risk areas at all levels of potential ecological risk of the heavy metals (Cd and Hg) in soil with clear pollution trend and all heavy metals in soil was draw by indicator kriging. Results The validation results showed that the probability of error decision was between 0.45~26.94 that was considered acceptable. Conclusion The method can be used for the division of soil heavy metal ecological risk region of farmland, and it provides scientific basis for soil pollution remediation.