When evaluating the heavy metal content of soils and crops in the Dexing copper mine by using a single exceeded index, the authors found that excessive heavy metals in soil and in crop are not inconsistent with each other. Pb and Cd are not or rarely ex-cessive in soil, but they seriously exceed the set standard in crops. In order to solve this mismatch phenomenon, the authors, on the basis of National Food Hygiene Standards,proposed the method of soil heavy metals risk threshold based on crop safety and deter-mined the risk threshold in farmland soils of the Dexing copper mine. This method overcomes the shortcomings of the deviation of the standard-surpassing boundary and the unitary soil consideration during the evaluation based on National Standards and hence can be more flexibly used in agricultural production.%采用单项超标指数法对德兴铜矿区土壤和农作物重金属含量进行评价，发现土壤中与农作物中的重金属超标不一致，尤其是Pb、Cd在土壤中不超标或超标很少，但在农作物中超标极其严重。为了解决土壤超标与农作物超标不匹配问题，依据国家食品卫生标准，提出基于农作物安全的土壤重金属风险阈值方法，给出德兴地区农田土壤重金属超标风险阈值。该方法解决了国家标准评价时出现的超标界限偏差和考虑土壤使用情况单一的问题。很好地为德兴铜矿地区水稻和小白菜种植地点的选择和超标土壤的治理提供科学依据，更加灵活地应用于农业生产过程中。
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