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
Returns
tibble
Details
DCOREMN=mean(NCORE[patchij])
where NCORE[patchij] is the number of core areas.
DCORE_MN is an 'Core area metric'. It summarises each class as the mean 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.
Units
None
Range
DCORE_MN > 0
Behaviour
Equals DCORE_MN = 0 if NCORE = 0 for all patches. Increases, without limit, as the number of disjunct core areas increases.
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