基于栅格DEM 的沙兰河流域河网提取及局地暴雨洪水模拟

本文基于美国Global Land Cover Facility（GLCF）的全球90m精度的DEM数据源，采用作者开发的DEM凹陷区域识别与处理、河网自动生成与流域划分软件，提取了黑龙江省沙兰镇以上沙兰河流域河网相关信息。同时结合沙兰河暴雨洪水的相关报道，采用内含简化水文过程的二维水动力学模型，直接用假设的降水过程作为输入，估算了沙兰河流域局地暴雨的洪水过程与低洼地的洪水淹没过程。结果表明，从公开的高分辨率全球DEM数据自动提取指定流域信息，并利用降雨数据作为模型输入，采用上述模型，可以为山洪灾害防治分析提供有力的技术工具和手段。

Simulation of storm flood basing on deriving drainage networks from grid DEM and 2-D hybrid approach in Shalan river basin

Digital data on the position and characteristics of river networks and catchment are important for the understanding of local river basin. They are necessary for the input of simulat ing hydraulic or hydrology model. Based on the 2004 ( 3) Arc Second SRTM Elevat ion, a digital elevation data with 90m resolution, published by Global Land Cover Facility ( GLCF) , USGS, which is available at: http: glcf. umiacs. umd. edu??data??srtm, a software on extracting drainage networks from raster DEM has been developed to extractriver network of Shalan river basin of drainage area is 114. 3km2 . Good visual consistence was obtained to compare the extracted river networks information with field observation in other references, as well as the inter - basins boundary and drainage area. Using supposed rainfall process of 6.10??storm in Shalan catchment and extracted drainage network, a hybrid approach which combines simplified hydrology process with 2- D hydraulic model was developed and used to simulate the storm flash flood in Shalan riverbasin in Heilongjiang Province. The result shows, the maximum flood discharge in outlet is 415m3??s, the maximum water depth nearby the Shalan town is 1. 3m, flash flood lasting period is 5~ 6 hr, and 1~ 2 hr for water depth over 1 m at the same location. The flood zone mainly locates along the Shalan River with width of 500m. Though default of flood observat ion and remote sensing data, the simulat ion shows reasonable agreement with real situation. The results imply that the proposed software and approach are apt to simulate storm flash flood with reliable resolution in mountainous area or valleys based on river networks extracted automatically from grid DEM and the hybrid approach which combines simplified hydrology process with 2-D hydraulic model. I can be served as a new tool for analysis of national storm flash flood in mountainous area or valleys