遥感、GIS辅助下流域空间离散化方法研究

STUDY ON SPATIAL DISCRETIZATION IN BASIN SIMULATION AIDED BY RS AND GIS

以江西兴国潋水河流域为研究区 ,设计了流域—子流域—水文响应单元的空间离散方案和实现步骤。在遥感、GIS技术支持下 ,应用了基于栅格的数字高程模型 (DEM)的流域水文建模方法 ,进行了流域河网的自动生成 ,子流域的自动划分以及流域边界生成研究 ,根据流域地形特征将整个流域分割成多个子流域。在分割出的每个子流域内部 ,通过数字土壤图和土地利用图的叠加统计分析生成单一土地利用类型和土壤类型组合的水文响应单元 ,将研究区离散成为 6 2个子流域 ,399个水文响应单元 ,实现了分布式流域建模的空间离散化 ,在这个过程中 ,研究解决了平坦区河网精确生成和流域边界的误差改正等技术难题。

The watershed subwatershed hydrological response units discretization scheme were designed in the study area of Lianshui basin, Xingguo County, Jiangxi Province. Supported by RS and GIS. The method of distributed hydrological modeling based on raster Digital Elevation Models (DEM) was applied to generate basin network, to divide subwatershed and generate basin boundary automatically. The subwatershed discretization divides the watershed into subwatersheds based on the topographic features of watershed, and each subwatershed can be farther portioned into multiple hydrologic response units (HRUs) which are unique soil/land use combinations within the subwatershed and modeled through statistical spatial overlay analysis. At last 62 sub basins and 399 hydrological response units were produced in the study area and spatial discretization of the basin were successfully realized. A series of technological problems such as the accurate generation of basin network in plate area and error correction of basin boundary were solved in the research process.