【摘要】 为了减小数字高程模型(DEM)分辨率对地形指数计算的影响,开发了一种不受DEM空间分辨率影响的地形指数计算方法。选取汉江上游褒河流域作为研究区域,通过引入分辨率因子考虑DEM空间分辨率对单宽上坡集水面积的影响,应用分形方法处理DEM空间尺度对地形坡度的影响,将该算法应用到褒河流域DEM数据的计算中。结果表明:此法可以成功地由低分辨率的DEM数据获得与目标高分辨率精度相仿的地形指数分布,能在一定程度上消除DEM空间分辨率对地形指数计算的影响,因而对无资料地区的水文预报有着十分重要的现实意义。更多还原

【Abstract】 A scale invariant model for down scaling topographic index distributions was developed to reduce the effect of digital elevation model(DEM) resolution on the topographic index calculation.The method used a resolution factor and a fractal method to fine the scaled steepest slope in the topographic index taking into account the effects of the DEM resolution.The method successfully derived fine resolution DEM topographic index distributions using only coarse resolution DEM.The scale invariant model was applied to the Baohe River Basin.The results show that the down scaled topographic index distribution is similar to a target topographic index distribution with same of the effects of the DEM resolution on the topographic index removed by the analysis.This method can be used for hydrologic predictions in ungauged basins.更多还原