农艺措施对重金属污染小麦田的修复研究

Remediation of Heavy Metal Contaminated Wheat Fields by Agronomic Measures

为探讨在受重金属污染的土壤上生产出符合安全标准粮食的农业生产技术,实现重金属污染农田边生产边修复,以有污水灌溉历史的农田为研究对象,研究以农艺措施为主的不同修复措施对农田土壤中不同重金属累积量、小麦产量以及小麦籽粒中重金属累积量的影响。结果表明,污灌农田土壤Cd、Zn存在超标现象,增施有机肥、钝化剂和深翻耕等措施均能显著降低土壤中Cd、Pb、Zn有效态含量,其中以综合修复措施效果最佳,有效态Cd、Zn、Pb含量分别比修复前降低46.8%、31.2%、45.5%;增施钝化剂、有机肥和深翻处理均显著降低小麦籽粒中Cd的累积量,实施修复措施的小麦籽粒中Cd、Pb、Zn含量全部达到安全标准。因此,在重金属污染农田通过农艺修复措施能够实现小麦安全生产。

In order to explore the technology for producing grains meeting the food safety standards in soil polluted by heavy metals,and realize the remediation of heavy metal contaminated farmland at the same time of production,the farmlands with sewage irrigation history were taken as research objects to compare different remediation measures.The effects of different remediation measures on the accumulation of different heavy metals in soil and wheat grains and the wheat yield were analyzed.The results showed that Cd and Zn in the soil with sewage irrigation exceeded standard seriously.The contents of Cd,Pb and Zn in soil could be significantly reduced by applying organic fertilizer,passivator and deep ploughing.The comprehensive remediation measure had the best effect,and the contents of Cd,Zn and Pb reduced by 46.8%,31.2%and 45.5%compared to before remediation.The application of passivator and organic fertilizer and deep ploughing all reduced the accumulation of Cd in wheat grains significantly,and the contents of Cd,Pb and Zn in wheat grains after remediation all met the safety standards.Therefore,safe production of wheat could be achieved in heavy metal contaminated farmland through agronomic remediation measures.