采用室内培养的方法,比较石灰、钙镁磷肥、硅肥、紫云英、猪粪和泥炭等几种改良剂作用下Cu、Cd污染酸性水稻土中不同形态重金属的动态变化.结果表明,土壤添加石灰、钙镁磷肥、硅肥、紫云英和猪粪培养120d期间,土壤pH值呈现先增加至最大值而后缓慢降低的趋势,但均高于对照,而添加泥炭后土壤pH值略有下降.各改良剂的使用均显著降低了土壤水溶态和交换态Cu、Cd含量,且在培养期间呈现先逐渐降低至最小值而后再增加的趋势.相关分析结果表明,土壤水溶态和交换态Cu、Cd含量与土壤pH值之间均存在极显著的负相关关系.土壤添加改良剂后碳酸盐结合态、铁锰氧化物结合态、有机结合态和残渣态Cu、Cd含量均有不同幅度的增加,说明改良剂的应用能够使土壤重金属由有效态向某些潜在有效态或无效态转变,从而达到修复重金属污染土壤的目的.%Limestone, calcium magnesium phosphate fertilizer, silicon fertilizer, Chinese milk vetch, and pig manure, respectively, was added into Cu and Cd contaminated acidic paddy soil, then the incubation experiment was conducted to investigate the dynamics of heavy metal fractions after the application of amendments. The results showed that during the 120days, the soil pH was increased with incubation time, and decreased slowly after reaching a peak. Soil pH in treatments with these amendments was all higher than that of the control. However, soil pH was slightly decreased after peat application, as compared with the control. Concentrations of soil water soluble and exchangeable Cu and Cd were significantly decreased with the application of all amendments during the 120d incubation period, and the values decreased gradually to a minimum, then increased again. There were significant negative correlations between soil pH and concentrations of soil water soluble and exchangeable Cu and Cd. Application of amendments increased the concentrations of carbonate-bound, Fe-Mn oxides-bound, organic-bound, residual Cu and Cd by different levels. This implied that all these amendments could transform soil heavy metals from available fractions to potentially available or non-available fractions, and then remedied the heavy metals contaminated soils.
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