Method for extracting width of river channels within basin by using digital elevation model

Abstract

The invention discloses a method for extracting the width of river channels within a basin by using a digital elevation model. The method comprises the following main steps: the digital elevation model (DEM) data of the basin are extracted; the slope grids, river channel grids and confluence accumulative grids of the basin are calculated according to the digital elevation model (DEM) data of the basin; near-river channel slope grids are extracted by using the slope grids and the river channel grids; near-river channel confluence accumulative grids are extracted by using the confluence accumulative grids and the river channel grids; moving average calculation is performed on the basis of the near-river channel slope grids, so that moving averaged near-river channel slope grids can be obtained; and the width of the river channels within the basin is extracted on the basis of the near-river channel confluence accumulative grids and the moving averaged near-river channel slope grids. The method of the invention has the advantages of stable and reliable data sources, high calculation efficiency, objective and reasonable results and the like. With the method adopted, the rapid calculation and extraction of the width of the river channels within the basin can be benefitted.

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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