基于DEM的单位汇水面积尺度转换(英文)

编号 zgly0001585555

文献类型 期刊论文

文献题名 基于DEM的单位汇水面积尺度转换(英文)

作者 杨昕  汤国安  肖晨超  高毅平  祝士杰 

作者单位 KeyLaboratoryofVirtualGeographicEnvironment  NanjingNormalUniversity  MinistryofEducation  InstituteofRemoteSensingandGeographicInformationSystem  PekingUniversity 

母体文献 Journal of Geographical Sciences 

年卷期 2011年04期

年份 2011 

分类号 P208 

关键词 DEM  specificcatchmentarea  scaleeffect  scalingmodel  JiuyuanGully 

文摘内容 Specific Catchment Area (SCA) is defined as the upstream catchment area of a unit contour. As one of the key terrain parameters, it is widely used in the modeling of hydrology, soil erosion and ecological environment. However, SCA value changes significantly at different DEM resolutions, which inevitably affect terrain analysis results. SCA can be described as the ratio of Catchment Area (CA) and DEM grid length. In this paper, the scale effect of CA is firstly investigated. With Jiuyuangou Gully, a watershed about 70 km2 in northern Shaanxi Province of China, as the test area, it is found that the impacts of DEM scale on CA are different in spatial distribution. CA value in upslope location becomes bigger with the decrease of the DEM resolution. When the location is close to downstream areas the impact of DEM scale on CA is gradually weakening. The scale effect of CA can be concluded as a mathematic trend of exponential decline. Then, a downscaling model of SCA is put forward by introducing the scale factor and the location factor. The scaling model can realize the conversion of SCA value from a coarse DEM resolution to a finer one at pixel level. Experiment results show that the downscaled SCA was well revised, and consistent with SCA at the target resolution with respect to the statistical indexes, histogram and spatial distribution. With the advantages of no empirical parameters, the scaling model could be considered as a simple and objective model for SCA scaling in a rugged drainage area.