Coefficient of variation shape index (Shape metric)
Usage
lsm_l_shape_cv(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
$$SHAPE_{CV} = cv(SHAPE[patch_{ij}])$$
where \(SHAPE[patch_{ij}]\) is the shape index of each patch.
SHAPE_CV is a 'Shape metric'. The landscape is summarised as the Coefficient of variation
of all patches in the landscape. SHAPE describes the ratio between the actual perimeter of
the patch and the square root of patch area.
Units
None
Range
SHAPE_CV >= 0
Behaviour
Equals SHAPE_CV = 0 if all patches have an identical shape index.
Increases, without limit, as the variation of the shape index 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
Patton, D. R. 1975. A diversity index for quantifying habitat "edge".
Wildl. Soc.Bull. 3:171-173.