Retaining Relative Height Information: An Enhanced Technique for Depression Treatment in Digital Elevation Models
| Autor: | Chunying Ma, Peijun Shi, Jing Zheng, Hanxin Gao, Bo Chen, Yao Xiao |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Pixel
drainage network Water supply for domestic and industrial purposes Geography Planning and Development Flow (psychology) Elevation Terrain Hydraulic engineering depression treatment sinks and depressions digital elevation model hydrologic analysis Aquatic Science Structural basin Geodesy Biochemistry Direct flow Path (graph theory) Digital elevation model TC1-978 TD201-500 Geology Water Science and Technology |
| Zdroj: | Water, Vol 13, Iss 3347, p 3347 (2021) Water; Volume 13; Issue 23; Pages: 3347 |
| ISSN: | 2073-4441 |
| Popis: | This study presents an enhanced variant of the priority-flood based algorithm proposed by Wang and Liu for treating depressions in digital elevation models (DEMs). The enhanced variant redefines spill elevation, the key concept of the original algorithm, as the lowest elevation that a pixel needs to have to ensure a non-ascending path toward the border of the DEM, plus the larger of a small number (~0.001) and the difference between the unaltered elevation values of the focal pixel and its immediate downhill neighbor. This redefinition is adopted to obtain an intermediate elevation surface to direct flow and ultimately to carve the original DEM. Each carving starts from a depression bottom and propagates downstream until a downhill cell is guaranteed in the original DEM. Tests of these algorithms on a complex terrain of the 260,000 km2 Sichuan structural basin in China shows that the enhanced algorithm maximally preserves the original flow directions and extracts realistic drainage networks. Retaining the relative heights, and therefore flow directions, of cells within depressions allows the new algorithm to offer a depressionless DEM with small modification of its origin for further hydrologic applications. The enhanced depression treatment algorithm is provided as the freely available tool BNUSinkRemv. |
| Databáze: | OpenAIRE |
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