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SPLIT (class level)

Source: R/lsm_c_split.R
lsm_c_split.Rd

Splitting index (Aggregation metric)

Usage

lsm_c_split(landscape, directions = 8)

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).

Value

tibble

Details

$$SPLIT = \frac{A^2} {\sum \limits_{j = 1}^{n} a_{ij}^2}$$ where \(a_{ij}\) is the patch area in square meters and \(A\) is the total landscape area.

SPLIT is an 'Aggregation metric'. It describes the number of patches if all patches of class i would be divided into equally sized patches.

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

Units

None

Range

1 <= SPLIT <= Number of cells squared

Behaviour

Equals SPLIT = 1 if only one patch is present. Increases as the number of patches of class i increases and is limited if all cells are a patch

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

Jaeger, J. A. 2000. Landscape division, splitting index, and effective mesh size: new measures of landscape fragmentation. Landscape ecology, 15(2), 115-130.

See also

lsm_p_area, lsm_l_ta,
lsm_l_split

Examples

landscape <- terra::rast(landscapemetrics::landscape)
lsm_c_split(landscape)
#> # A tibble: 3 × 6
#>   layer level class    id metric value
#>   <int> <chr> <int> <int> <chr>  <dbl>
#> 1     1 class     1    NA split   68.1
#> 2     1 class     2    NA split   75.5
#> 3     1 class     3    NA split   13.1