城市绿色基础设施多尺度雨洪调控效应及其空间配置优化研究

Increasing urbanization, the global climate change and the need for enhanced sustainability of urban water resources pose significant challenges to conventional stormwater management. Innovative approaches are needed in order to mitigate the risk of flooding, pollution, and enhance beneficial uses of urban waters. The adverse impacts of urbanization and climate change on hydrology and water quality can be mitigated by applying urban green infrastructure (UGI) practices and accordingly develop the resilience stormwater management system for the construction of the sponge city. However, the functions of UGI is regionally specific and will change from site to watershed scale. Consequently, the design of UGI requires a great consideration of site and regional conditions and evaluate both the localized site-scale and the cumulative effects of implementing the UGI practices across a broad watershed landscape and find out how to optimally select and place UGI practices and optimize their functions on managing the stormwater. In this research, Taken Nanjing, Xianlin district as a case study, this research tries firstly, to explore the different hydrologic function of different vegetation and UGI/LID (Low Impact Development) type based on field surveys and observations, and then to evaluate the impacts of land use and UGI/LID change on hydrology in the different heavy rainfall events by coupling the SWMM (Storm water Management Model) with the WRF (Weather Research and Forecasting) model; Finally, simulate and evaluate the hydrological change and the vulnerability to extreme events by the SWMM model under the different scenarios of urban planning and expansion, then to answer questions about“what if” scenarios and to find out the potentiality of UGI/LID managing the stormwater on a watershed scale. Through the multi-scale analysis, this research will try to build an effective and resilience stormwater management system and evaluate its stormwater management performances by coupling the process of “land surface pattern-local climate-hydrology response”, and under the consideration of Sponge City/LID idea. The results will help to develop the guidance for UGI planning and design based on the sound, locally relevant, multi-disciplinary science and multi-scale research and then will help the city cope with stormwater and climate change.

城市绿色基础设施（UGI）是实施弹性雨洪管理和建设海绵城市的重要空间载体。但不同UGI及其空间配置的雨洪调控机理、影响因素和效能均具有明显的区域特质和多尺度效应。因而，如何从场地到流域多尺度分析UGI的雨洪调控效应，因地制宜地优化UGI空间配置，构建弹性雨洪管理系统，是目前城市应对雨洪迫切需要解决的重要问题。研究以南京仙林副城为例，针对南京的雨洪特征，基于定点观测和多源数据，应用雨洪管理模型（SWMM）、中尺度气象模式（WRF）等，在历史雨情特征量化和暴雨情景再现的基础上，从场地到流域多尺度分析、模拟和量化UGI/LID的雨洪调控效应、机理和影响因素，科学评价UGI/LID的综合效益，以期在海绵城市/LID雨洪管理理念的指导下，将“陆面过程-局地气候-水文效应”相耦合，阐明流域应对雨洪的脆弱性，优化UGI/LID的配置模式，建设长期有效的弹性雨洪管理系统，提升城市应对雨洪和气候变化的能力。

城市绿色基础设施是基于自然的方案、应对城市雨洪的重要举措，是实施弹性雨洪管理和建设海绵城市的重要空间载体。但不同UGI及其空间配置的雨洪调控机理、影响因素和效能均具有明显的区域特质和多尺度效应。因而，如何从场地到流域多尺度分析UGI的雨洪调控效应，因地制宜地优化UGI空间配置，构建弹性雨洪管理系统，是目前城市应对雨洪迫切需要解决的重要问题。本研究重点从场地尺度（屋顶绿化）-校园尺度-小流域尺度-城市尺度，针对不同降雨特征，基于定点观测和多源数据（包括卫星遥感数据、LiDAR、无人机等），应用雨洪管理模型（SWMM）和SUSTAIN 模型等，在对历史雨情特征量化和暴雨情景再现的基础上，从场地到流域多尺度分析、模拟和量化UGI/LID的雨洪调控效应、机理和影响因素，科学评价了UGI/LID的综合效益，提出了优化UGI/LID的配置模式，可为建设长期有效的弹性雨洪管理系统、提升城市应对雨洪和气候变化的能力提供重要支撑。