Standard deviation of patch area (Area and edge metric)
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.
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