湖库流域氮磷非点源污染水陆响应遥感解析

Non-point source (NPS) pollution is one of the important reasons for eutrophication in in-land Lake, a lot of research on water pollution prevention and related projects were done. However, it’s not enough to consider the water body as a single unit to study the water pollution problem. As research continues, it’s proved that the more effective way to prevent the water pollution should consider the water body and land as a whole unit under the sustainable development background. Especially, it’s one of the key scientific problems to resolve water pollution problems by studying on responses between the uplands and water body in the watershed scale..In this project, a classic in-land lake catchment, with the name of Chaohu Lake was considered as the study areas. Taking the advantage of remote sensing(RS) tech，simulation tech, spatial analysis tech, and satellite ground synchronization experimental method, and coupling the RS inversion model, NPS pollution model and water quality model, to build a multivariate model system driven by RS on mechanism research of terrestrial NPS Pollution to water quality. In turn, the spatial analysis on nutrients distribution between the land and water body and the response mechanism from land to water were identified at the pixel scale, which finally clarified the relationship on NPSP and water quality. This work can provide the venerable area and control area of NPS pollution，which will provide effective suggestions on water environment comprehensive management.

非点源污染是导致内陆湖库水体富营养化的重要原因之一，我国在相关水污染防治方面开展了有益的研究和示范工作，但单纯以湖库水体为治理对象难以取得满意效果。随着研究的深入，逐步证实了将陆面和水体作为一个研究整体才能更有效地实现流域水污染防控，其中非点源污染的水陆响应关系是解决流域水污染防治的关键科学问题之一。本项目拟选择我国典型湖库——巢湖流域为研究对象，从流域整体性出发，利用遥感监测技术、数值模拟技术、空间分析技术和星地同步地面监测实验等手段，通过耦合定量遥感反演模型、非点源污染模拟模型和水动力模型，建立遥感驱动的流域水陆响应多元模型系统，并以遥感像元为基本模拟单元，从湖库流域非点源污染氮磷流失时空特征和水质氮磷浓度时空分布特征等方面，探明流域陆面非点源污染与湖库水质变化的内在关系，实现湖库流域非点源污染关键区和重点防治区的识别，最终为流域水环境管理提供技术支持。

非点源污染是我国湖库水污染防治领域的重点和难点问题，其水陆响应关系也是目前解决流域水污染防治的关键科学问题之一。本项目以巢湖流域为研究示范对象，从典型湖库流域污染控制角度出发，分别应用遥感技术、地面监测技术、模型模拟技术和同步实验手段，通过耦合定量遥感模型、非点源污染模型和水质模型等多元模型，从点和面两个方面开展陆地非点源污染与水体水质间的动态响应机制研究，具体研究内容包括基于遥感像元尺度的流域非点源污染负荷估算、湖库氮磷浓度遥感反演、陆面非点源氮磷污染与湖库水质变化时空响应关系等。结果分析表明，巢湖水体氮磷浓度与陆面氮磷面源污染的空间响应程度较高，时间尺度上，水陆的总磷污染在汛期的响应程度较高，总氮存在一定的时间滞后性，建议针对巢湖流域北部的陆源氮磷面源污染高排放区进行源头管控，并重点针对汛期时段，加强农田灌溉用水和农田退水水质水量同步监测，及时掌握面源污染物排放情况及其对水质的影响，实现湖库流域非点源污染关键区和重点防治区的识别。本项目以探明非点源污染与水质变化的内在联系为目标，在湖库流域水资源综合管理的实践中具有重要的科学意义和社会意义。本项目构建了模型体系2个，构建模型相关数据库2套，具体包括巢湖陆地面源污染评估模型和巢湖水体氮磷水质反演模型；巢湖星地同步遥感监测数据库和巢湖流域面源污染监测评估数据库。本项目研究成果荣获生态环境部科技进步二等奖一项，共发表论文6篇，其中SCI收录论文3篇，北大核心期刊收录2篇，CSSCI期刊收录1篇。