Standard deviation of patch area (Area and edge metric)
Usage
lsm_c_area_sd(landscape, directions = 8)
Value
tibble
Arguments
landscape
A categorical raster object: SpatRaster; Raster* Layer, Stack, Brick; stars or a list of SpatRasters
directions
The number of directions in which patches should be
connected: 4 (rook's case) or 8 (queen's case).
Details
$$AREA_{SD} = sd(AREA[patch_{ij}])$$
where \(AREA[patch_{ij}]\) is the area of each patch in hectares.
AREA_SD is an 'Area and Edge metric'. The metric summarises each class
as the standard deviation of all patch areas belonging to class i.
The metric describes the differences among patches of the same class i in
the landscape.
Units
Hectares
Range
AREA_SD >= 0
Behaviour
Equals AREA_SD = 0 if all patches are identical in size.
Increases, without limit, as the variation of patch areas increases.
References
McGarigal K., SA Cushman, and E Ene. 2023. FRAGSTATS v4: Spatial Pattern Analysis
Program for Categorical Maps. Computer software program produced by the authors;
available at the following web site: https://www.fragstats.org