南京郊区某菜地土壤镉污染水平及其来源调查

通过南京郊区某菜地表层土壤、土壤剖面、大气降尘、灌溉水、土壤溶液、化肥的Cd含量研究,结果表明,菜地表层土壤存在一定程度的Cd污染,且土壤剖面由深及浅表现出累积趋势。表层土壤Cd的总体含量水平为0.30mgkg-1,其中自然背景含量为0.20mgkg-1,人为作用叠加含量为0.10mgkg-1。在人为污染来源中,大气降尘对菜地的贡献率为79%,化肥的贡献率为17%,而灌溉水仅为4%。工厂应采取适当措施避免废气直接排入大气中,菜农应施用有机肥,因为这些措施会有效控制进入菜地的镉含量。

Investigation of Cadmium Pollution and Its Major Sources in Vegetable Land in the Suburb of Nanjing City

We investigated the concentration of cadmium in surface soil, soil depth, atmospheric deposition, irrigation water, soil solution and fertilizer in vegetable land in suburb of Nanjing. The result suggests that the soils were contaminated by cadmium to some extend, with accumulative trend from deep layer to surface layer. The concentration of cadmium in surface soil was 0.30mg kg-1 as a whole, of which the background level was 0.20mg kg-1 and the anthropogenic influence was 0.10mg kg-1. Across the whole vegetable land, atmospheric deposition was the main source of cadmium responsible for 79% of total inputs. In contrast, 17% of cadmium input was from irrigation water and only 4% from fertilizers.