农田镉砷污染防控与作物安全种植技术探讨

文章综述了农田镉、砷污染现状、环境风险及其来源,阻控作物镉、砷吸收的关键技术环节,包括农业投入品控制、水分管理、土壤钝化调控、叶面调理、低吸收作物品种选择与替代种植、秸秆移除削减等。结合"土十条",提出镉、砷污染农田作物安全种植的几点思考:一是建立基于耕地-农产品污染等级的安全种植技术体系;二是采取集成农艺措施进行综合防控,重点提出作物安全种植VIRL(Variety-Input and Irrigation-Root zone and Removal of straw-Leaf blade)技术模式。该模式将源头预防(农业投入)、过程阻控(作物本身镉、砷吸收特性,影响作物地下部与地上部镉、砷吸收的各个环节)、末端治理(秸秆移除修复)高度统一起来,然后根据耕地-农产品污染等级,采取或紧或松的关键(联合)技术调控,实现镉、砷污染农田的安全种植;三是对镉、砷复合污染农田同步防控问题进行了探讨和展望。

Probes of prevention and control of farmland pollution by cadmium & arsenic and crop production safety

Farmland pollution by cadmium and arsenic, at present, is one of the major environmental problems confronting agricultural production. In this paper, the situation of farmland pollution by cadmium and arsenic and its risks to health are reviewed and the key technologies to obstruct and control cadmium and arsenic from being absorbed by crops are observed, such as agricultural input control, water management, soil passivant regulation, leaf surface conditioning, selection and substitute planting of low absorption crop varieties, and removal of straws. Combining the Soil Pollution Prevention Action Plan, the following ideas are proposed in this paper regarding the production safety on cadmium- and arsenic- polluted farmland:(1)determine an appropriate technology for safe production according to the farmland pollution index and (2) control and prevent pollution in comprehensive ways using integrated agronomic measures. In this paper, the control and prevention of farmland pollution by cadmium and arsenic is explained, and regarding crop production safety, a technical mode, VIRL(Variety-Input and Irrigation-Root zone and Removal of Straw-Leaf blade), is presented. This mode highly integrates source control(agricultural inputs), process control(crops'' native characteristics of cadmium and arsenic absorption, various elements in both underground and aboveground parts affecting cadmium and arsenic absorption), and terminal control of farmland. Then, a key(joint) technical regulation, strict or loose, is carried out based on the farmland pollution level, thus securing safe production on cadmium- and arsenic- polluted farmland.