采用Tessier连续提取法研究了上海市典型绿地土壤的重金属Cu、Zn、Pb和Cd的形态分布.结果表明:上海绿地土壤中Cu主要以有机态的形式存在,Zn主要以铁锰氧化态和残渣态的形式存在,Pb主要以残渣态的形式存在,只有Cd的可交换态所占比例比较高.有机态Cu与Cu的其它各形态之间呈极显著相关,Zn的各形态之间均达到了极显著相关性;而Pb除可交换态外,其它各形态之间也达到了显著或极显著相关;Cd除了残渣态外,其它各形态之间达到了显著或极显著相关.土壤性质不同对重金属形态分布影响不同,有机态和残渣态受土壤的CaO、Fe2O3和MnO影响大,碳酸盐结合态主要受pH影响,除Zn外,Pb、Cd和Cu的铁锰氧化态质量分数受铁锰质量分数影响小.土地利用方式影响重金属的形态分布,钢铁厂重金属形态活性相对最小,而试剂溶剂厂可交换态和潜在可交换态Cd质量分数均最高.%An experiment was conducted to study the form distribution of heavy metals (Cu, Zn, Pb, Cd) in typical green-belt soils in Shanghai by using Tessier's sequential extraction procedure. Results showed that Cu was dominated by organic form, Zn was mostly in the Fe-Mn oxides and residual forms, Pb existed mainly in residual form, while the exchangeable from was most for Cd. According to the results of regression analysis, there was an extremely significant correlation between organic-Cu and the other Cu forms, and also among all forms for Zn. The other forms for Pb had significant or extremely significant correlation, with the exception of the exchangeable form. While the significant or extremely significant correlation was found among all forms for Cd except the residual form. In addition, the effects of soil properties on the form distribution of heavy metals were different. The effects of contents of CaO, Fe2O3 and MnO in soil on organic and residual forms of heavy metals were the most obvious, soil pH mainly influenced the distribution of carbonate form of heavy metals,and contents of Fe and Mn showed less influence on Fe-Mn oxide forms of Pb, Cd and Cu, with the exception of Zn. And different land-use types had some effects on the form distribution of heavy metals, and the activities of heavy metals were the least in the iron-steel factory; however, the exchangeable from and potentially exchangeable from of Cd were dominant in the chemical-reagent factory.
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