r.watershed Calculates hydrological parameters and RUSLE factors. The manual page of this module is available here: http://grass.osgeo.org/grass70/manuals/html70_user/r.watershed.html elevation Name of input elevation raster map image/tiff image/tiff depression All non-NULL and non-zero cells are considered as real depressions image/tiff image/tiff flow Name of input raster representing amount of overland flow per cell image/tiff image/tiff disturbed_land For USLE image/tiff image/tiff blocking For USLE. All non-NULL and non-zero cells are considered as blocking terrain. image/tiff image/tiff threshold Minimum size of exterior watershed basin integer max_slope_length For USLE float convergence 1 = most diverging flow, 10 = most converging flow. Recommended: 5 integer 5 memory Maximum memory to be used with -m flag (in MB) integer 300 -s SFD: single flow direction, MFD: multiple flow direction boolean true false false -4 Allow only horizontal and vertical flow of water boolean true false false -m Only needed if memory requirements exceed available RAM; see manual on how to calculate memory requirements boolean true false false -a See manual for a detailed description of flow accumulation output boolean true false false -b Flow direction in flat areas is modified to look prettier boolean true false false grass_resolution_ns Resolution of the mapset in north-south direction in meters or degrees This parameter defines the north-south resolution of the mapset in meter or degrees, which should be used to process the input and output raster data. To enable this setting, you need to specify north-south and east-west resolution. float meters meters degrees 25 grass_resolution_ew Resolution of the mapset in east-west direction in meters or degrees This parameter defines the east-west resolution of the mapset in meters or degrees, which should be used to process the input and output raster data. To enable this setting, you need to specify north-south and east-west resolution. float meters meters degrees 25 grass_band_number Band to select for processing (default is all bands) This parameter defines band number of the input raster files which should be processed. As default all bands are processed and used as single and multiple inputs for raster modules. integer

accumulation Number of cells that drain through each cell image/tiff image/tiff

drainage Name for output drainage direction raster map image/tiff image/tiff

basin Unique label for each watershed basin image/tiff image/tiff

stream Name for output stream segments raster map image/tiff image/tiff

half_basin Each half-basin is given a unique value image/tiff image/tiff

length_slope Slope length and steepness (LS) factor for USLE image/tiff image/tiff

slope_steepness Slope steepness (S) factor for USLE image/tiff image/tiff