A Method of Using Digital Elevation Model to Extract the Channel Width in Watershed

Abstract

The invention discloses a method for extracting the width of a river channel in a watershed by using a digital elevation model, which includes the following main steps: extracting digital elevation model (DEM) data of the watershed; calculating the gradient grid of the watershed, the river channel grid and the accumulation of confluence by using the DEM data of the watershed Grid; use the slope grid and river grid to extract the slope grid near the river; use the cumulative grid and river grid to extract the cumulative grid near the river; perform slider average calculation on the basis of the slope grid near the river , to obtain the slope raster near the river after the average calculation of the slider; combined with the cumulative grid of confluence near the river, the slope raster near the river after the average calculation of the slider can extract the channel width in the watershed. The invention has the advantages of stable and reliable data sources, high calculation efficiency, objective and reasonable results, etc., and is beneficial to the rapid calculation and extraction of river channel width in a watershed.

Description

technical field [0001] The invention belongs to the technical field of hydrology, and in particular relates to a method for extracting the width of a river in a watershed by using a digital elevation model. Background technique [0002] With the development of technologies such as remote sensing, geographic information, and digital watersheds, the distributed hydrological model based on the grid digital elevation model (DEM, Digital Elevation Model) has become an important model for its full consideration of the spatial variation of rainfall and underlying surface conditions. Trends in watershed hydrological modeling. When modeling a distributed hydrological model, one of the main difficulties is how to obtain the channel width of each channel grid cell in the watershed. In order to further promote the development of watershed hydrological models, it is necessary to study the calculation method of channel width in more depth. [0003] Channel width is a key parameter in th...

AI Technical Summary

Problems solved by technology

However, the width of the river channel calculated by the current method is generally that the width of the downstream channel is always greater than the width of the upstream channel. However, in the actual state, the channel does not always increase continuously from upstream to downstream. The upstream channel is narrower

Therefore, the channel width calculated by the current method does not fully conform to the objective reality, which limits the application of the channel width parameter in distributed modeling and is not conducive to the development of domestic distributed hydrological models.

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