皖北砂姜黑土Cu、Cd、Zn形态分布特征

Characteristics of Combined Forms,Contents and Distribution of Copper,Cadmium and Zinc in Shajiang Black Soil of the North of Anhui

采用小麦农田取样,对土壤中的重金属运用连续提取方法,研究了皖北砂姜黑土中Cu、Cd、Zn的化学形态、含量及分布特征.结果表明:在砂姜黑土中,重金属Cu、Cd、Zn含量的平均值高于该土地土壤的背景值.土壤中Cu、Cd、Zn的残留态在总量中所占比例比较高,交换态、有机态、碳酸盐结合态含量明显低于残留态.在三种元素中,Zn的化学形态变化趋势最为一致,表现为残留态>碳酸盐结合态>铁锰氧化物结合态>有机态>交换态;统计分析表明:Cu、Cd、Zn在砂姜黑土中的形态分布与土壤PH值、有机质含量等因素相关;该土壤受到了一定程度的污染.

Successive extraction method was adoped to study the forms, contents and distribution of Copper, Cadmium and Zinc in shajiang black soil of the north of Anhui Province by field sampling. The results showed that the average concentration of Copper, Cadmium and Zinc in shajiang black soil of the north of Anhui Province were higher than those from backgrounds. The residual forms of Copper, Cadmium and Zinc had much higher proportions of the total, the contents of the exchangeable forms, organic combined forms and carbonate combined forms were obviously lower than the contents of the residual forms. In the three elements, the chemical forms of Zinc changed consistently. It showed that the residual forms 〉 carbonate combined forms〉 Fe-Mn oxide combined forms 〉 organic combined forms 〉 exchangeable forms. The statistical analysis indicated that, the major factors which affects the chemical forms of Copper, Cadmium and Zinc in shajiang black soil were pH and organic matter. Generally, the soil pH had the negation correlation with the proportions of exchangeable and organically bound. The contents of organic matter had positive correlation with the proportions of exchangeable and organically bound. The soils of the area had been polluted partially.