Provided by: grass-doc_8.4.0-1_all
NAME
r.li.edgedensity - Calculates edge density index on a raster map, using a 4 neighbour algorithm
KEYWORDS
raster, landscape structure analysis, patch index
SYNOPSIS
r.li.edgedensity r.li.edgedensity --help r.li.edgedensity [-b] input=name config=name output=name [patch_type=string] [--overwrite] [--help] [--verbose] [--quiet] [--ui] Flags: -b Exclude border edges --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: input=name [required] Name of input raster map config=name [required] Configuration file output=name [required] Name for output raster map patch_type=string The value of the patch type It can be integer, double or float; it will be changed in function of map type
DESCRIPTION
r.li.edgedensity calculates: • the density of all edges of patch type k , or • the density of all edges in the sampling area if k is not specified, with: • k: patch type • m: number of patch types • n: number of edge segments of patch type k • eik :total edge length in the landscape involving patch type k • Area: total landscape area The unit is meters per hectare.
NOTES
Do not use absolute path names for the config and output file/map parameters. If the "moving window" method was selected in g.gui.rlisetup, then the output will be a raster map, otherwise an ASCII file will be generated in the folder C:\Users\userxy\AppData\Roaming\GRASS8\r.li\output\ (MS-Windows) or $HOME/.grass8/r.li/output/ (GNU/Linux). If the input raster map contains only NULL values then r.li.edgedensity consider to have 0 patches. If area is 0 r.li.edgedensity returns NULL; this is only possible if input raster is masked.
EXAMPLES
To calculate the edge density index on map my_map, using my_conf configuration file (previously defined with g.gui.rlisetup) and saving results in my_out, run: r.li.edgedensity input=my_map conf=my_conf output=my_out To calculate edge density index of patch_type 34, using "my_conf" configuration file and on map "my_map", saving results in "my_out" file run: r.li.edgedensity input=my_map conf=my_conf output=my_out patch_type=34 Forest map (Spearfish sample dataset) example: g.region raster=landcover.30m -p r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())" r.li.edgedensity input=forests conf=movwindow7 out=forests_edgedens_mov7 r.univar forests_edgedens_mov7 Forest map (North Carolina sample dataset) example: g.region raster=landclass96 -p r.mapcalc "forests = if(landclass96 == 5, 1, null() )" r.li.edgedensity input=forests conf=movwindow7 out=forests_edgedensity_mov7 # verify r.univar forests_edgedensity_mov7 r.to.vect input=forests output=forests type=area d.mon wx0 d.rast forests_edgedensity_mov7 d.vect forests type=boundary
SEE ALSO
r.li - package overview g.gui.rlisetup
REFERENCES
McGarigal, K., and B. J. Marks. 1995. FRAGSTATS: spatial pattern analysis program for quantifying landscape structure. USDA For. Serv. Gen. Tech. Rep. PNW-351. (PDF)
AUTHORS
Serena Pallecchi student of Computer Science University of Pisa (Italy). Commission from Faunalia Pontedera (PI), Italy (www.faunalia.it) Markus Metz
SOURCE CODE
Available at: r.li.edgedensity source code (history) Accessed: Thursday Aug 01 11:30:06 2024 Main index | Raster index | Topics index | Keywords index | Graphical index | Full index © 2003-2024 GRASS Development Team, GRASS GIS 8.4.0 Reference Manual