土壤固相组分对镉吸持试验研究

Study on the Retention of Cd in different Soil Solid Components

选用三种不同类型的土壤，用连续提取法去除土壤固相中碳酸盐（石灰性土壤）、氧化锰、有机质、无定型氧化铁和晶型氧化铁组分，制得分离某一组分或某几个组分后土壤钙饱和的样品，研究土壤固相各组分对Ｃｄ吸持的影响。研究表明，Ｃｄ的吸持能力除受土壤理化性质的影响外，土壤固相组分及其相互作用直接控制着土壤对重金属Ｃｄ的吸持。

The effect of different soil components on the retention of Cd was investigated by equilibrating standard solutions (pH=7) of Cd isothermically with soil fractions devoid of given soil solid components. The soil fractions were prepared by use of sequential extraction method, and then saturated with Ca. The soils used in this paper were chao soil (Calcareous), red soil (acid) and a neutral paddy soil. The soil: solution ratio in the adsorption experiments was 1:10. The experimental results show that the retention ability of soil is detenmined lavgely by the interaction among soil solid components. Both the interaction among solid components and the effect of a given component on the retention of Cd were different for different soils.