delineate_valley: Extract the river valley from the DEM

In rcrisp: Automate the Delineation of Urban River Spaces

Extract the river valley from the DEM

Description

The slope of the digital elevation model (DEM) is used as friction (cost) surface to compute the cost distance from any grid cell of the raster to the river. A characteristic value (default: the mean) of the cost distance distribution in a region surrounding the river (default: a buffer region of 2 km) is then calculated, and used to threshold the cost-distance surface. The resulting area is then "polygonized" to obtain the valley boundary as a simple feature geometry.

Usage

delineate_valley(dem, river)

Arguments

dem	SpatRaster object with the digital elevation model of the region
river	An object of class sf::sf or sf::sfc representing the river

Value

River valley as a simple feature geometry of class sfc_MULTIPOLYGON

Examples

bucharest_osm <- get_osm_example_data()
bucharest_dem <- get_dem_example_data()
delineate_valley(bucharest_dem, bucharest_osm$river_centerline)

rcrisp documentation built on Nov. 24, 2025, 5:07 p.m.