基于水资源可持续利用的农业面源治理工程应用评价

Application Evaluation of Agricultural Non-point Source Treatment Project Based on Sustainable Utilization of Water Resources

农业面源污染作为云南九大高原湖泊主要污染源之一,具有广泛性、复杂性及不确定性,严重威胁到湖泊水生态环境安全。为全面推动农业面源污染防治工作,有效削减流域农业面源污染负荷,结合洱海农业面源污染末端拦截及综合利用试点工程建设,探索水资源可持续利用下的农业面源污染治理模式,不断推进湖泊水生态保护和水污染防治,为云南九大高原湖泊乃至全国其他类型湖泊的面源污染防控提供技术示范和成功案例。试点工程雨季可通过有效拦截冲击性负荷,减少入湖面源污染;旱季可拦截回用农业灌溉回归水,整体压缩区域农田灌溉的洱海新鲜水取用量,以减排倒逼节水,保障农田灌溉用水。分析结果表明:试点工程通过有效发挥拦截、调蓄、回用功能,每年可综合利用回用拦蓄水量791×10^(4)m^(3),可削减总氮56.8t、总磷2.8t入湖量,提高洱海农业面源污染治理效益。

Agricultural non-point source pollution,as one of the main pollution sources of nine plateau lakes in Yunnan Province,has universality,complexity and uncertainty,which seriously threatens the safety of lake water ecological environment.In order to comprehensively promote the prevention and control of agricultural nonpoint source pollution and effectively reduce the load of agricultural non-point source pollution in the watershed,this paper explores the treatment mode of agricultural non-point source pollution under the sustainable utilization of water resources in combination with the pilot project construction of the end interception and comprehensive utilization of agricultural non-point source pollution in Erhai.At the same time,this paper continuously promotes lake water ecological protection and water pollution control,providing technical demonstration and successful cases for non-point source pollution control of nine plateau lakes in Yunnan Province and even other types of lakes in China.The rainy season of the pilot project can effectively intercept the impact load and reduce the non-point source pollution entering the lake.The return water for agricultural irrigation can be intercepted and reused in dry season,and fresh water intake of Erhai Lake for farmland irrigation in the whole area can be compressed to reduce emissions and compel water saving,thus ensuring irrigation water for farmland.The analysis results show that the pilot project can effectively utilize the interception,regulation and storage,and reuse functions to comprehensively use and reuse the intercepted water of 7.91 million m^(3) each year,which can reduce 56.8 tons of total nitrogen and 2.8 tons of total phosphorus into the lake,and improve the benefit of agricultural non-point source pollution control in Erhai Lake.