再生水回灌的农业环境风险及对策

随着我国城市化进程加快和经济的快速发展,需水量大幅增加,造成局部缺水严重,与此同时城市污水处理厂的数量和规模不断增大,而这些污水处理厂出水(再生水)直接排入河流而没有被再次利用造成资源浪费,再生水回用后对土壤环境的不确定性影响是造成再生水利用率较低的重要原因。本文系统总结了再生水回用对土壤环境的盐分、有机质组分、微生物、重金属、难降解有机污染物的国内外的研究成果,指出:(1)再生水回用于灌溉在提高肥力的同时,能够引起土壤盐分的累积;(2)再生水回用于灌溉能够导致土壤微生物菌群的变化,也有引起环境卫生的风险,但是风险极低;(3)再生水灌溉能够引起部分重金属元素的累积;(4)再生水灌溉对土壤难降解有机污染物的影响是未来研究的热点。

Research Process on Influence of Reclaimed Water Recycling on Soil Environment

As China's urbanization and rapid economic development,there is a substantial increase in water demand,resulting in severe local water shortages.At the same time,the number of urban sewage treatment plant and scale are increasing.The sewage treatment plant effluent(reclaimed water) directly flows into rivers without being used again,resulting in a waste of resources.The reason for lower utilization of wastewater is the uncertainties of reclaimed water recycling on soil environment.This paper systematically summarizes the advance in reclaimed water reusing on soil salinity,organic matter composition,micro-organisms,heavy metals,refractory organic pollutants,and pointing out:(1) Reclaimed water reuse for irrigation,while improving soil fertility,soil salinity can cause cumulative;(2) Reclaimed water reuse for irrigation can lead to changes in microbial flora,but also cause environmental health risk,extremely low;(3) Reclaimed water for irrigation can cause some accumulation of heavy metals;(4) Reclaimed water irrigation on soil refractory organic pollutants are research on for future.