r.stream.slope - GRASS GIS manual

NAME

r.stream.slope - Calculates local parameters for slope subsystem.

KEYWORDS

raster, hydrology, stream network, stream local parameters

SYNOPSIS

r.stream.slope

r.stream.slope --help

r.stream.slope direction=name elevation=name [difference=name] [gradient=name] [maxcurv=name] [mincurv=name] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

direction=name [required]: Name of input raster map with flow direction
elevation=name [required]: Name of input elevation raster map
difference=name: Name for output local downstream elevation difference raster map
gradient=name: Name for output local downstream gradient raster map
maxcurv=name: Name for output local downstream maximum curvature raster map
mincurv=name: Name for output local downstream minimum curvature raster map

DESCRIPTION
OPTIONS
EXAMPLE
SEE ALSO
AUTHOR

DESCRIPTION

r.stream.slope calculates local downstream elevation change and local downstream minimum and maximum curvature.

OPTIONS

direction: Flow direction: name of input direction map produced by r.watershed or r.stream.extract. If r.stream.extract output map is used, it only has non-NULL values in places where streams occur. NULL (nodata) cells are ignored, zero and negative values are valid direction data if they vary from -8 to 8 (CCW from East in steps of 45 degrees). Direction map shall be of type CELL values. Region resolution and map resolution must be the same.
elevation: Elevation: name of input elevation map or any other map we want to calculate. Map can be of type CELL, FCELL or DCELL. It is not restricted to resolution of region settings like direction.
difference: Output downstream elevation difference: difference between elevation of current cell and downstream cell. Shall always be positive. Negative values show, that current cell is pit or depression cell. Module is prepared to be used with elevation but can be also used to calculate local difference of any feature along watercourses in slope subsystem. In that way elevation map must be replaced by map we want to calculate. If we use different map than elevation, rest of parameters have no sense to calculate
gradient: Output downstream gradient: Downstream elevation difference divided by distance.
maxcurv: Output maximum linear curvature along watercourse. Calculated along watercourse between highest upstream cell, current cell and downstream cell (there can be only one or no downstream cell but more than on upstream)
mincurv: Output minimum linear curvature along watercourse. Calculated along watercourse between lowest upstream cell, current cell and downstream cell (there can be only one or no downstream cell but more than on upstream)

EXAMPLE

g.region -p -a raster=elevation
r.watershed elevation=elevation threshold=10000 drainage=dirs stream=streams
r.stream.slope dir=dirs elevation=elevation difference=downstream_elev_difference \
  gradient=downstream_gradient maxcurv=downstream_maxcurv mincurv=downstream_mincurv

AUTHOR

Jarek Jasiewicz, Adam Mickiewicz University, Geoecology and Geoinformation Institute.

SOURCE CODE

Available at: r.stream.slope source code (history)