非点源污染尺度效应及尺度转换方法研究

Nonpoint source (NPS) pollution is one of the prominent problems in many watersheds across the world. The scale effect and the related scaling technology of NPS pollution is the focus of the water environment research. By monitoring and modeling NPS pollution at different scales, this study use a variety of technologies, such as information collection, local investigation, field monitoring, model simulation, time series analysis, fractal theory and geostatistical analysis. A typical watershed in the Three Gorges Reservoir Region is selected in the research. In this study, the specific contents include: to reveal the export process of NPS at different scales, and to quantify the features of NPS loads at multiple spatial-temporal scales; to identify the distribution of rainfall and soil properties, to explain the interaction between dominant factors and their features at multiple scales, and to propose the mechanism of scale effect; to develop an scaling technology by incorporating different statistical and physical-based models, and quantify the related uncertainty. Finally, an integrated framework will be provided for NPS study by considering the scale effect and the China’s actual conditions. This study would lead to the improvement of prevention-oriented management for NPS pollution and further enrich the theory and methodology of watershed science. Meanwhile, this study would target on NPS pollution issues for the Three Gorges Reservoir Area and provide some important reference for the protection of water quality safety in such regions.

随着非点源污染逐渐成为水环境的主要威胁，非点源污染的尺度效应及尺度转换方法已成为流域水环境研究关注的焦点和待解决的难题。本项目以三峡库区典型嵌套流域为研究对象，采用多尺度梯级观测与宏观模型模拟相结合的研究模式，同时结合资料收集、现场调查、野外观测、计算机模拟、时间序列分析、分形理论和地统计学等多种研究手段，探讨不同时间/空间尺度上非点源污染输出的差异性，阐明非点源污染输出规律的尺度效应；以降雨、土壤理化性质为例，揭示主导因子的相互作用及多尺度状态，阐述非点源污染尺度效应的形成机制；耦合多种统计方法和机理模型，提出非点源污染尺度转换方法，量化尺度转换结果的不确定性，最终形成适合我国国情、考虑尺度效应的流域非点源污染研究方案。研究成果将有利于非点源污染防控理念的创新，有助于完善我国流域水环境管理理论和方法，同时可为保障三峡水库水质安全和水污染防治提供参考。

本项目围绕非点源尺度效应及转换方法这一关键科学问题，以三峡库区典型嵌套流域为研究对象，采用多尺度梯级观测与宏观模型模拟相结合的研究模式，同时结合资料收集、现场调查、野外观测、计算机模拟、时间序列分析、分形理论和地统计学等多种研究手段，开展了小尺度流域非点源传输-消纳机理、流域尺度非面源入水过程及主导因子、嵌套流域非面源传输规律及环境效应、非点源污染尺度转换方法和非点源多尺度防控技术集成等五方面研究内容。重要成果包括：（1）揭示了非点源污染入水过程及其沟塘作用机制，阐明了嵌套流域非点源污染传输的时空尺度及其主导因子，拓展了非点源污染研究基础理论；（2）开发了沟塘过程的小流域模型和基于主导因子的GC-ANPSM模型等2个具有自主知识产权的面源评价新方法；（3）建立了3种非点源污染尺度转换方法和1种多尺度措施技术集成模式，为非点源污染尺度转换研究提供了重要支撑。相关成果方面，共在国内外权威杂志发表论文25篇、授权知识产权2项，其中10篇发表在Water Research、Water Resources Research、Journal of Hydrology等水科学三大顶级刊物上；人才培养方面，完成人入选中组部青拔人才，同时培养了3名博士生、4名硕士生；社会服务方面，完成人受邀担任了Journal of Hydrology等SCI期刊副主编，相关成果为第二次全国污染源普查核算提供了技术支撑，形成了重要的行业影响。