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SHDI (landscape level)

Source: R/lsm_l_shdi.R
lsm_l_shdi.Rd

Shannon's diversity index (Diversity metric)

Usage

lsm_l_shdi(landscape)

Arguments

landscape

A categorical raster object: SpatRaster; Raster* Layer, Stack, Brick; stars or a list of SpatRasters.

Value

tibble

Details

$$SHDI = - \sum \limits_{i = 1}^{m} (P_{i} * \ln P_{i})$$ where \(P_{i}\) is the proportion of class i.

SHDI is a 'Diversity metric'. It is a widely used metric in biodiversity and ecology and takes both the number of classes and the abundance of each class into account.

Units

None

Range

SHDI >= 0

Behaviour

Equals SHDI = 0 when only one patch is present and increases, without limit, as the number of classes increases while the proportions are equally distributed

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

Shannon, C., and W. Weaver. 1949. The mathematical theory of communication. Univ. IllinoisPress, Urbana

See also

lsm_c_pland

Examples

landscape <- terra::rast(landscapemetrics::landscape)
lsm_l_shdi(landscape)
#> # A tibble: 1 × 6
#>   layer level     class    id metric value
#>   <int> <chr>     <int> <int> <chr>  <dbl>
#> 1     1 landscape    NA    NA shdi    1.01