基于养分回用-化肥替代的农业面源污染氮负荷削减策略及技术

有效削减农业面源氮污染负荷是提升水环境质量的关键,也是当前关注的热点之一。氮排到水体是污染源,但其本身是农作物生长必需的营养元素。为此,提出了基于养分回用-替代化肥的农业面源污染氮负荷削减策略,利用农业生产系统对农业面源污染排放的氮进行消纳和回用,减少农田化肥氮投入并有效削减排入到水环境中的氮,达到农业生产与环境保护的双赢。重点介绍了面源污水中氮的农田直接回用、水生植物回收-有机肥还田替代、环境材料吸附净化-回收还田等几种技术途径及其应用,并指出了目前存在的不足及以后发展的方向。

Agricultural non-point source pollution nitrogen load reduction strategy and technology of nutrient reusing in agricultural fields to replace fertilizer

The effective reduction of agricultural non-point source nitrogen pollution load is the key to improve water environmental quality,and it is also one of the hot issues in the world.Nitrogen is a pollutant when discharged into the water,but it is an essential macro-nutrient for crops.Therefore,a strategy of reusing the nitrogen from agricultural non-point source pollution as a nutrient in the agricultural system to replace chemical fertilizer was put forward in this paper.Then the technical approaches to reduce the N load from agricultural non-point source pollution based on this strategy were introduced,including the direct irrigation with the polluted water into farmland,using the aquatic plants to absorb the nitrogen then produce organic fertilizer and apply to the farmland,using the environmental material to adsorb the nitrogen and recycled into farmland.The shortcomings of the current research and future development direction were also discussed.