LPI (landscape level)

Largest patch index (Area and Edge metric)

Usage

lsm_l_lpi(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

$$LPI = \frac{\max (a_{ij})} {A} * 100$$ where \(max(a_{ij})\) is the area of the patch in square meters and \(A\) is the total landscape area in square meters.

The largest patch index is an 'Area and edge metric'. It is the percentage of the landscape covered by the largest patch in the landscape. It is a simple measure of dominance.

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

Units

Percentage

Range

0 < LPI <= 100

Behaviour

Approaches LPI = 0 when the largest patch is becoming small and equals LPI = 100 when only one patch is present

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

See also

lsm_p_area, lsm_l_ta,
lsm_c_lpi

Examples

landscape <- terra::rast(landscapemetrics::landscape)
lsm_l_lpi(landscape)
#> # A tibble: 1 × 6
#>   layer level     class    id metric value
#>   <int> <chr>     <int> <int> <chr>  <dbl>
#> 1     1 landscape    NA    NA lpi     17.7