Perimeter (Area and edge metric))
Arguments
- landscape
Raster* Layer, Stack, Brick, SpatRaster (terra), stars, or a list of rasterLayers.
- directions
The number of directions in which patches should be connected: 4 (rook's case) or 8 (queen's case).
Details
$$PERIM = p_{ij}$$ where \(p_{ij}\) is the perimeter in meters.
PERIM is an 'Area and edge metric'. It equals the perimeter of the patch including also the edge to the landscape boundary. The metric describes patch area (larger perimeter for larger patches), but also patch shape (large perimeter for irregular shapes).
References
McGarigal, K., SA Cushman, and E Ene. 2012. FRAGSTATS v4: Spatial Pattern Analysis Program for Categorical and Continuous Maps. Computer software program produced by the authors at the University of Massachusetts, Amherst. Available at the following web site: http://www.umass.edu/landeco/research/fragstats/fragstats.html
Examples
lsm_p_perim(landscape)
#> # A tibble: 27 × 6
#> layer level class id metric value
#> <int> <chr> <int> <int> <chr> <dbl>
#> 1 1 patch 1 1 perim 4
#> 2 1 patch 1 2 perim 12
#> 3 1 patch 1 3 perim 130
#> 4 1 patch 1 4 perim 4
#> 5 1 patch 1 5 perim 4
#> 6 1 patch 1 6 perim 20
#> 7 1 patch 1 7 perim 8
#> 8 1 patch 1 8 perim 10
#> 9 1 patch 1 9 perim 4
#> 10 1 patch 2 10 perim 38
#> # … with 17 more rows