【摘要】 对常规钝化剂在大田条件下对Cd污染农田(小麦种植棕壤)的修复效果进行评价。结果表明,钙镁磷肥、氯铝酸钙、凹凸棒土3种钝化剂均能不同程度地提升土壤pH、降低土壤有效态Cd含量以及小麦秸秆和籽粒中Cd含量,并提高小麦产量。施加钙镁磷肥1 500 kg/hm~2(记为CMP1500)后,土壤pH提升效果最明显,pH提高了0.55;施加氯铝酸钙9 000 kg/hm~2后土壤有效态Cd降幅最大,下降了57.4%。CMP1500处理后小麦秸秆和籽粒中Cd含量降幅最大,分别下降了73.4%、72.1%。CMP1500处理小麦增产最明显,增幅为16%。以土壤pH、土壤有效态Cd含量、小麦秸秆中Cd含量、小麦籽粒中Cd含量和小麦产量为评价指标,通过主成分分析研究不同处理的综合修复效果,结果表明,CMP1500的修复效果最好,可用于Cd污染农田小麦种植棕壤的原位钝化修复。更多还原

【Abstract】 The effects of conventional passivating agents on remediation performance of Cd-contaminated brown soil with wheat cropping under field conditions were evaluated. The results indicated that the three experimental passivators, calcium magnesium phosphate, chloride calcium aluminate and attapulgite, could increase soil pH,reduce the available Cd content in soil and Cd accumulation in wheat straw and grain, as well as increase the wheat yield to different degrees. Application of 1 500 kg/hm~2 calcium magnesium phosphate(recorded as CMP1500) increased soil pH by 0.55 unit, which showed the most obvious effects on soil pH increasing in all treatments. Available Cd content in soil decreased by 57.4% with application of 9 000 kg/hm~2 chloride calcium aluminate, which was the largest decline in the experiment. Treatment CMP1500 had the best effect on both Cd decreasing in wheat and wheat yield increasing, which decreased Cd contents in straw and grain by 73.4% and 72.1% respectively, and increased wheat yield by 16%. Soil pH,available Cd in soil, Cd content in wheat straw and grain and wheat yield were taken as parameters to evaluate the remediation effects of three experimental passivating agents by principle components analysis. Treatment CMP1500 was recommended as the best treatment for in situ remediation of Cd-contaminated brown soil with wheat cropping.更多还原