DEM数据分辨率对黑河金盆水库流域地形参数提取的影响分析

根据陕西省黑河金盆水库流域不同分辨率的DEM数据,采用数理统计方法分析DEM数据分辨率的变化对流域地形参数提取的影响,为建立流域分布式水文模型前期DEM数据分辨率的选择提供参考依据。对流域不同分辨率DEM数据分析得到:随着流域DEM数据分辨率的降低,流域的粗糙度值、最大坡度及平均坡度值、最大高程值、平面曲率和剖面曲率最大值及最小值的绝对值均有减小的趋势,最小高程有增大的趋势,坡向在DEM数据分辨率降低到一定程度时会出现较大变化,地形指数变化范围更趋于集中。

An Analysis of Terrain Parameters Extraction in Heihejinpen Reservoir Basin Affected by DEM Data Resolution

Based on the different resolutions digital elevation model(DEM) data in Heihe Jinpen reservoir basin in Shaanxi Province,the mathematical statistical method is adopted to analyze the impact of changes in the DEM data resolution on the basin topographic parameters extracted so as to provide a reference for the establishment of the choice of DEM data resolution in distributed watershed hydrological model in this paper.The results obtained from analyzing different resolutions DEM data in the basin indicate: With the decrease in resolution of the DEM data,there appears to have decreasing tendency in basin roughness value,the maximum slope and average slope value,the maximum elevation value,the maximum and minimum absolute value of plane and profile curvature,the minimum elevation trends to increase;there will be a larger change in the slope direction when the DEM resolution drops to a certain extent,and the topographic index range tend to be more concentrated.