有机肥中重金属特征及其控制技术研究进展

Research Progress on Characteristics of Heavy Metals in Organic Manure and Control Technology

随着工业的快速发展,农药、肥料及地膜等系列农用化学物质的广泛使用,农田土壤重金属污染越来越严重。重金属进入土壤后,其难移动性导致大量积累,造成土壤环境污染,影响植物生长,危及人类的健康。有机肥是我国农业生产中非常重要的肥料,其来源也十分广泛。施用有机肥是提高作物产量的必要措施,同时也是土壤重金属的主要输入途径之一,研究有机肥的重金属特征及其有关控制技术对农产品安全和有机废弃物的再利用具有重要意义。文章就畜禽排泄物堆肥、污泥堆肥、生活垃圾堆肥和沼肥等主要有机肥料的重金属来源、含量以及不同溯源有机肥料对土壤中重金属有效性的影响进行综述,重点介绍了畜禽排泄物堆肥中重金属含量和饲料添加剂之间的关系,为农田土壤重金属污染防治和农产品安全提供科学依据。除从有机肥的源头控制重金属外,文章主要介绍了化学法、生物吸附法、生物淋滤法和电化学法等重金属控制技术,针对各种控制方法,阐述了其原理、应用实例、优缺点及研究进展情况,提出了解决有机肥重金属污染问题的思路和方法,为有机肥料的资源化利用提供了参考。最后指出,为了实现养殖业与种植业的安全链接,除选用重金属含量低的有机肥,通过相关技术有效控制有机肥中的重金属外,还要注重肥料用量、施肥时间、施肥技术的合理选择,从最大程度上避免有机肥料给作物和人类带来的副作用。

As the wide use of pesticides, fertilizers, agricultural films, and rapid industrialization, more and more agricultural soils were polluted by heavy metals. Heavy-metal pollution in soil represents an important environmental problem due to their accumulation throughout the food chain leads to serious agricultural and health problems. As an important fertilizer in Chinese agriculture, organic manure is one of the main measurements for increasing crop yields and used widely. However, organic manure is the major source of heavy metal in soils. It is significant to research on the heavy-metal characteristics in organic manure and control technology, which contributes to improving the safety of agricultural products and also agricultural wastes reutilization. In this paper, the origin and content of heavy metals in organic manure, which including animal feces, sewage sludge, municipal solid waste and biogas manure, and affection of manure on heavy metal availability in soils were reviewed. The relationship between the heavy metals content of animal feces composts and feed additives was mainly introduced, to provide the scientific basis for the remediation of heavy metal pollution and the safety of agricultural products. The current researches and control technologies, including chemical, biological adsorption, biological leaching and electrochemical technology, which were summarized at home and abroad. Based on the principle, application examples, and merits or demerits of the various remediation methods, the ideas and methods were presented to provide reference for the resource utilization of organic manure. Finally, in order to realize the breeding and planting safety, it need select low heavy-metal organic manure. In particular, the amount of manure, fertilization time and fertilization technology should be chosen to avoid the side effects of organic manure to the crops and human.