DCORE_CV (landscape level)

Coefficient of variation number of disjunct core areas (Core area metric)

Usage

lsm_l_dcore_cv(
  landscape,
  directions = 8,
  consider_boundary = FALSE,
  edge_depth = 1
)

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

Value

tibble

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 the landscape as the Coefficient of variation of all patches belonging to the landscape. 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 all patches in the landscape and is easily comparable because it is scaled to the mean.

Units

None

Range

DCORE_CV >= 0

Behaviour

Equals DCORE_CV = 0 if all patches have the same number of disjunct core areas. Increases, without limit, as the variation of number of disjunct core 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

Examples

landscape <- terra::rast(landscapemetrics::landscape)
lsm_l_dcore_cv(landscape)
#> # A tibble: 1 × 6
#>   layer level     class    id metric   value
#>   <int> <chr>     <int> <int> <chr>    <dbl>
#> 1     1 landscape    NA    NA dcore_cv  127.