基于流域GIS空间建模的雨洪模拟方法

Runoff Simulation Method Based on GIS Spatial Watershed Modeling

基于多层次GIS空间分析模型技术,系统地建立了从流域雨洪过程相关影响因子栅格化处理到产汇流过程模型的集成化模拟方法,首次实现了对流域内任意栅格单元内河道断面的径流过程线的可视化测算。同时还对于模型中单元水流长度与河道单元流速率定方法进行了优化改进。实例分析结果表明:模型结构更为严谨、参数设置更为科学,改进的技术方法对于福建汀江十年一遇洪水场次的模拟结果精度有明显提高,能够满足相关海绵城市规划应用需求。

Traditional hydrological models have high requirements on historical hydrological data,making it difficult to measure runoff process-es on any river channel cross section.In recent years,with the advancement of spatial information science and technology,the runoff spatio-tem-poral simulation method based on watershed rasterization technology has gradually developed.Based on the previous work and multi-level GIS spatial analysis model technology,we systematically established an integrated simulation method from the rasterization of relevant runoff process impact factors in the river basin to the process model of producing and confluent flow,and realized visual measurement of runoff process line of river section in any grid unit in the watershed.Meanwhile,we optimized and improved the method of determining the unit flow length and chan-nel unit flow rate in the model.The example analysis results show that the model structure is more rigorous and the parameter setting is more sci-entific.The proposed method can significantly improve the simulation accuracy of the ten-year flood event in Ting River,Fujian Province,and meet the application requirements of related sponge city planning.