子流域划分和DEM分辨率对SWAT径流模拟的影响研究

Influence of Watershed Subdivision and DEM Resolution on SWAT Runoff Simulation

应用SWAT分布式水文模型,选择秦淮河流域为研究区,在不同的子流域划分水平和DEM分辨率条件下,进行流域径流的模拟,进一步分析子流域划分和DEM分辨率对流域径流模拟结果的影响。研究结果表明:产流量随着子流域划分数目的增加几乎没有变化,最大相对偏差不超过5%;DEM分辨率的变化对径流的模拟影响也不大,尤其在DEM格网单元低于100m时,各种DEM格网单元模拟结果的相对偏差最大约为1%。

By using SWAT distributed hydrological model, the runoff of the Qinhuai River Basin was simulated under different wa tershed subdivisions and DEM resolution. The results show that the runoff yield hardly changes with the variation of subdivision amount, the maximal relative deviation is less than 5%, the DEM resolution has almost no effects on runoff yield, especially when the DEM resolution is below 100 meters, the simulations vary from 0 to 1%.