Research on Safe Utilization Technologies of Farmland Soil Polluted with Cadmium on Field Trials
For the soil contaminated by cadmium in various degrees around the Pearl River Delta township industrial region,phytoexclusion experiments by low cadmium accumulation rice varieties,immobilization experiments,phytoexclusion combined with immobilization experiments,intercropping and crop rotation experiments by hyperaccumulator and low Cd-accumulating cultivars were conducted on field.Results showed that planting low Cd-accumulating rice cultivars JDY998 and CSM in slight cadmium-contaminated soil could ensure safe production.Cd in rice grains decreased by 52.49％and 62.50％compared to the control in the soil with the addition dose of 4 500 kg/hm2 montmorillonite compound conditioner and 2 640 kg/hm2 functionalized montmorillonite conditioner respectively,which ensure safe production.Joint applica-tion of montmorillonite compound conditioner and low Cd-accumulating rice cultivar JDY998 made Cd in rice grains decrease 68.61％and ensure safe production.The Cd extraction rate of Sedum alfredii and the treatment of intercropping with corns could reach 7.90％and 7.22％respectively.Cd in soil reduced by 11.5％and 10.2％.Simultaneously,intercropping corns achieved safe output.Crop rotation by low Cd-accumulating rice cultivar JDY998 could achieve uninterrupted safe production.The soil remediation measures in this study provide a new alternative to safe utilization of Cd contaminated soil in various degrees.
万方数据
维普
