重金属Cu Pb Zn Cr Cd在土壤中的形态分布和转化

Form Distribution and Transformation of Heavy Metals of Cu, Pb, Zn, Cr and Cd in Soils

采用室外小区隔离实验方法,研究了外源可溶性重金属进入水稻土土壤(乌栅土)后的形态分布及其形态随时间的转化。结果表明,外源可溶性重金属进入土壤后迅速向各个形态转化,可溶态重金属的浓度进入土壤后迅速下降;交换态和碳酸盐态重金属浓度先微弱上升,然后迅速下降;铁锰氧化态重金属浓度先上升,在烤田期达到最大值,然后迅速下降,成熟期时又微弱上升;有机态重金属浓度不断上升;残渣态重金属变化不大。

Distribution of different form and transformation of soluble heavy metals of Cu, Pb, Zn, Cr and Cd in soils (Wushan) has been studied in the present investigation. It was discovered that water soluble heavy metals added to soils were rapidly transformed to other forms. As time went on, soluble fraction of heavy metals decreased rapidly; while exchangeable and carbonate fractions initially rose then decreased. Furthermore, Fe/Mn oxide bounded fraction increased initially and showed a peak at the time of soil drying, then decreased, while rose a little during the period of harvesting. Organic complex fraction rose sequently associating with that the level of residual fraction was relatively stable with little variation.