lsm_p_para {landscapemetrics} | R Documentation |
PARA (patch level)
Description
Perimeter-Area ratio (Shape metric)
Usage
lsm_p_para(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). |
Details
PARA = \frac{p_{ij}} {a_{ij}}
where p_{ij}
is the perimeter in meters and a_{ij}
is the
area in square meters.
PARA is a 'Shape metric'. It describes the patch complexity in a straightforward way. However, because it is not standarised to a certain shape (e.g. a square), it is not scale independent, meaning that increasing the patch size while not changing the patch form will change the ratio.
Because the metric is based on distances or areas please make sure your data
is valid using check_landscape
.
Units
None
Range
PARA > 0
Behaviour
Increases, without limit, as the shape complexity increases.
Value
tibble
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_p_perim
,
lsm_c_para_mn
,
lsm_c_para_sd
,
lsm_c_para_cv
,
lsm_l_para_mn
,
lsm_l_para_sd
,
lsm_l_para_cv
Examples
landscape <- terra::rast(landscapemetrics::landscape)
lsm_p_para(landscape)