DEM-based topographic characterization and quantification of surface depression storage are critical to hydrologic and environmental modeling. Mixed conclusions have been obtained from previous studies on the relationship between maximum depression storage (MDS) and DEM grid spacing, which is affected by different factors, such as topographic characteristics, surface delineation methods and DEM interpolation/aggregation methods. The objective of this study was to evaluate the effects of DEM resolution on topographic characterization with the consideration of these three factors. Twenty-three topographic surfaces (including ideal surfaces, laboratory-scale soil surfaces and watershed-scale land surfaces) were selected, and five software packages, ArcHydro, PCRaster, HEC-GeoHMS, TauDEM and PD (puddle delineation), were used for surface delineation. Our results indicated that MDS, maximum ponding area (MPA) and the number of puddles (NP) decreased with increasing grid spacing for most smoother surfaces due to the loss of topographic detail. For most rough surfaces (e.g., mountain-type surfaces with significant variations in surface elevations), however, the changing patterns of MDS and MPA varied with an increase in grid spacing mainly due to the unreal “artificial depressions/puddles” generated during the interpolation/aggregation process. This study emphasizes the importance of topographic characteristics, DEM resolution and surface delineation methods.
This is an open access article distributed under the Creative Commons Attribution License
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited