CPLAND (class level)

Core area percentage of landscape (Core area metric)

Usage

lsm_c_cpland(
  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

$$CPLAND = (\frac{\sum \limits_{j = 1}^{n} a_{ij}^{core}} {A}) * 100$$ where $a_{ij}^{core}$ is the core area in square meters and $A$ is the total landscape area in square meters.

CPLAND is a 'Core area metric'. It is the percentage of core area of class i in relation to the total landscape area. A cell is defined as core area if the cell has no neighbour with a different value than itself (rook's case). Because CPLAND is a relative measure, it is comparable among landscapes with different total areas.

Because the metric is based on distances or areas please make sure your data is valid using check_landscape.

Units

Percentage

Range

0 <= CPLAND < 100

Behaviour

Approaches CPLAND = 0 if CORE = 0 for all patches. Increases as the amount of core area increases, i.e. patches become larger while being rather simple in shape.

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_c_cpland(landscape)
#> # A tibble: 3 × 6
#>   layer level class    id metric value
#>   <int> <chr> <int> <int> <chr>  <dbl>
#> 1     1 class     1    NA cpland  8.44
#> 2     1 class     2    NA cpland  9.89
#> 3     1 class     3    NA cpland 26