油菜连作及施用堆肥对土壤镉赋存形态和生物有效性的影响  

Phytoavailability and Speciation of Cd in Contaminated Soil After Repeated Croppings of Oilseed Rapes and Amended with Compost

作　　者：吴飞龙[1,2] 苏德纯[1] 

机构地区：[1]中国农业大学资源与环境学院,北京100094 [2]福建省农业科学院农业工程技术研究所,福建福州350003

出　　处：《农业环境科学学报》2009年第4期658-662,共5页Journal of Agro-Environment Science

基　　金：国家科技支撑项目(2006BAD17B04);国家重点基础研究规划(973)项目(2002CB41C8C4)

摘　　要：通过温室土培盆栽试验,研究了重金属镉污染土壤上连作油菜及施用堆肥对土壤中镉赋存形态及生物有效性的影响。结果表明:(1)在油菜连作体系下,施用堆肥显著降低油菜地上部镉含量。施用堆肥改变了土壤镉赋存形态,显著降低土壤易溶态和碳酸盐结合态镉含量而增加土壤铁锰氧化物结合态镉含量,从而降低土壤镉的生物有效性。(2)在相同堆肥处理下,种植两茬油菜后的土壤易溶态和碳酸盐结合态镉含量与不种植油菜的处理相比显著降低;而土壤硫化物及有机结合态镉含量较对照有所上升,种植油菜对土壤铁锰氧化物结合态镉和残渣态含量影响不显著,但是不同积累镉能力油菜朱苍花籽和川油Ⅱ-93之间对土壤镉形态的影响差异不显著。Pot experiments were conducted under greenhouse conditions to investigate Cd speciation sand phytoavailability in Cd contaminated soil after repeated croppings of different oilseed rape species and amended with compost. A Cd-accumulator oilseed rape Zhucang Huazi （ZC） and a non-accumulator oilseed rape Chuanyou Ⅱ-93 （ CY ） were used in the study. A modified BCR three-step sequential extraction procedure was used to determine Cd speciation in the Cd contaminated soil. The results showed that amended with compost could reduce the phytoavailability of Cd in the contaminated soil. Cd concentrations in shoot tissues of the two oilseed rape cultivars decreased significantly when the soil amended with compost. Addition of compost to soil significantly reduced the concentration of Cd in the exchangeable and weak acid soluble fraction, but concentration of Cd in oxidisable fraction increased significantly. With the same compost amendment rate, Cd concentration in the exchangeable and weak acid soluble fraction decreased significantly after repeated croppings of oilseed rapes in the Cd contaminated soil. However, there were no significant differences in Cd concentrations of reducible fraction and oxidisable fraction between repeated croppings of oilseed rapes or not. No significant difference in Cd speciation was observed in the Cd contaminated soil between repeated croppings of Cd-accumulator oilseed rape Zhucang Huazi （ZC） and non-accumulator oilseed rape Chuanyou Ⅱ-93 （ CY ）. Hence, repeated croppings of oilseed rape and compost amendment significantly reduced the availability of Cd in contaminated soil.

关 键 词：镉 赋存形态 堆肥 油菜 

分 类 号：X53[环境科学与工程—环境工程]