上海市宝山区土壤重金属含量及其分异特征

Contents and Differential Characteristics of Heavy Metals in Soils Found in Baoshan District, Shanghai

通过详细的调查分析,研究了上海市宝山区土壤重金属污染现状.从土壤种类来看,路边土壤重金属污染最为严重,菜区土壤次之,公园土壤则有轻微污染.表层土壤重金属全量之间存在较好的相关性,污染区往往出现数个元素含量同时增高的现象,呈现复合污染的趋势.表层土壤中Pb、Cu、Cd、Zn全量和土壤某些理化性质呈较显著的正相关.随着化肥及城市固体废弃物的施入,Pb、Cu、Cd、Zn等元素不断积累,全量增高.菜区和路边表层土壤中Pb含量明显高于底层土壤,公园土壤剖面重金属含量从上至下呈较明显下降趋势.城市化进程加剧了上海市城郊土壤中重金属的累积.

An intensive investigation has been conducted to study the contents and pollution effects of heavy metals in different kinds of soil profiles (0～(10 cm), 10～(20 cm), and 20～(30 cm)) in (Shanghai's) Baoshan district. Comparisons among various soil types indicate that roadside soils show the greatest concentration of heavy metals, soils in vegetable fields are less severely polluted, and parks are the least affected areas. Analyses indicate that significant correlations exist among the aggregates of heavy me-tals in the surface layers. The contents of several elements increase simultaneously when pollution becomes serious. Especially, there is correlation between Pb, Cu, Cd and Zn and physicochemical pro-perty in surface soils. Following the application of chemical fertilizer and solid waster material, the total contents of Pb, Cu, Cd and Zn all increase. In vegetable fields and parks, the surface soil contains more Pb than in the lower layers of the soil. In parks, these harmful elements tend to decrease with depth. Accumulation of heavy metals in rural areas is apparently due to the city's urbanization.