中文摘要：

高精度的数字高程模型（digital elevation model,DEM）数据是流域水文分析应用的基础。美国地质调查局新发布了全球高分辨率数字高程数据产品,其空间分辨率为1″（约为30 m）。为评价该数据在流域水文分析中的适用性,以鹤壁汤河流域为实验区,以机载LiDAR DEM数据为参考,统计了SRTM（1″）数据的高程误差,分析了坡度、坡向、地表覆盖等对误差的影响; 在基于地形的水文分析中,统计分析了SRTM（1″）数据误差对地形湿度指数、坡度坡长因子以及汇流动力指数等地形指数计算的影响; 最后选取流域汇水区面积、最长水流路径长度、形状系数、弯曲度系数等流域特征参数对两种DEM数据提取结果进行了对比。研究表明SRTM（1″） DEM数据具有较高的精度,原始数据均方根误差为5.98 m,在消除平面位移误差后减小为4.32 m。基于地形的水文分析表明SRTM DEM与LiDAR DEM计算结果具有一定的差异,地形湿度指数平均值略高,坡度坡长因子和汇流动力指数平均值偏低,离散度偏小,这与SRTM DEM在微地貌以及高坡度地形区存在失真相关。两种DEM数据提取流域特征参数差异较小。上述研究表明SRTM DEM（1″）数据在流域水文分析中具有较大的应用潜力。

英文摘要：

High-precision DEM data constitute the basis of watershed hydrology analysis. SRTM 1 Arc-Second Global elevation data, released by US Geological Survey, offer worldwide coverage data at a resolution of 1″ （30 m）. In order to evaluate and analyze the potential watershed hydrologic applications of SRTM, the authors used Tanghe watershed in Hebi as the experimental area and airborne LiDAR DEM data as a reference to assess vertical accuracy of SRTM （1″） data and the impact of slope, aspect, land cover on errors of SRTM （1″）. Hydrologic indexes based on the terrain, such as Topographic Wetness Index （TWI）, Length Slope Factor （LSF） and Stream Power Index （SPI）,were computed for analysis. Finally the basin’s characteristic parameters, such as catchment basin area, longest path length, shape factor, curvature coefficient, were extracted from the two DEM data and the results were compared. Studies show that SRTM （1″） DEM data have high precision, the RMSE of the original data is 5.98 m, and the RMSE of the data with the elimination of the plane displacement is reduced to 4.32 m. Hydrological analysis shows that SRTM DEM and LiDAR DEM produce some different results： the average of TWI of SRTM is slightly higher, the average of SLF and SPI is lower and the dispersion degree is smaller. This is associated with the terrain distortion of SRTM DEM in micro-topography and high slope area. The basin parameters extracted from both of the DEM data have smaller differences, which shows that SRTM DEM （1″） has wide application prospects in hydrologic analysis.