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ENN_MN (class level)

Source: R/lsm_c_enn_mn.R
lsm_c_enn_mn.Rd

Mean of euclidean nearest-neighbor distance (Aggregation metric)

Usage

lsm_c_enn_mn(landscape, directions = 8, verbose = TRUE)

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).

verbose

Print warning message if not sufficient patches are present

Value

tibble

Details

$$ENN_{MN} = mean(ENN[patch_{ij}])$$ where \(ENN[patch_{ij}]\) is the euclidean nearest-neighbor distance of each patch.

ENN_MN is an 'Aggregation metric'. It summarises each class as the mean of each patch belonging to class i. ENN measures the distance to the nearest neighbouring patch of the same class i. The distance is measured from edge-to-edge. The range is limited by the cell resolution on the lower limit and the landscape extent on the upper limit.

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

Units

Meters

Range

ENN_MN > 0

Behaviour

Approaches ENN_MN = 0 as the distance to the nearest neighbour decreases, i.e. patches of the same class i are more aggregated. Increases, without limit, as the distance between neighbouring patches of the same class i increases, i.e. patches are more isolated.

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

McGarigal, K., and McComb, W. C. (1995). Relationships between landscape structure and breeding birds in the Oregon Coast Range. Ecological monographs, 65(3), 235-260.

See also

lsm_p_enn, mean,
lsm_c_enn_sd, lsm_c_enn_cv,
lsm_l_enn_mn, lsm_l_enn_sd, lsm_l_enn_cv

Examples

landscape <- terra::rast(landscapemetrics::landscape)
lsm_c_enn_mn(landscape)
#> # A tibble: 3 × 6
#>   layer level class    id metric value
#>   <int> <chr> <int> <int> <chr>  <dbl>
#> 1     1 class     1    NA enn_mn  4.09
#> 2     1 class     2    NA enn_mn  3.61
#> 3     1 class     3    NA enn_mn  2