Coefficient of variation number of disjunct core areas (Core area 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).
- consider_boundary
Logical if cells that only neighbour the landscape boundary should be considered as core
- edge_depth
Distance (in cells) a cell has the be away from the patch edge to be considered as core cell
Details
$$DCORE_{CV} = cv(NCORE[patch_{ij}])$$ where \(NCORE[patch_{ij}]\) is the number of core areas.
DCORE_CV is an 'Core area metric'. It summarises each class as the Coefficient of variation of all patch areas belonging to class i. A cell is defined as core if the cell has no neighbour with a different value than itself (rook's case). NCORE counts the disjunct core areas, whereby a core area is a 'patch within the patch' containing only core cells. The metric describes the differences among patches of the same class i in the landscape and is easily comparable because it is scaled to the mean.
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