lsm_p_cai: CAI (patch level) In r-spatialecology/landscapemetrics: Landscape Metrics for Categorical Map Patterns

Description

Core area index (Core area metric)

Usage

  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 lsm_p_cai(landscape, directions, consider_boundary, edge_depth) ## S3 method for class 'RasterLayer' lsm_p_cai(landscape, directions = 8, consider_boundary = FALSE, edge_depth = 1) ## S3 method for class 'RasterStack' lsm_p_cai(landscape, directions = 8, consider_boundary = FALSE, edge_depth = 1) ## S3 method for class 'RasterBrick' lsm_p_cai(landscape, directions = 8, consider_boundary = FALSE, edge_depth = 1) ## S3 method for class 'stars' lsm_p_cai(landscape, directions = 8, consider_boundary = FALSE, edge_depth = 1) ## S3 method for class 'list' lsm_p_cai(landscape, directions = 8, consider_boundary = FALSE, edge_depth = 1) 

Arguments

 landscape Raster* Layer, Stack, Brick 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). consider_boundary Logical if cells that only neighbour the landscape boundary should be considered as core edge_depth Distance (in cells) a cell has the be away from the patch edge to be considered as core cell

Details

CAI = (\frac{a_{ij}^{core}} {a_{ij}}) * 100

where a_{ij}^{core} is the core area in square meters and a_{ij} is the area in square meters.

CAI is a 'Core area metric'. It equals the percentage of a patch that is core area. A cell is defined as core area if the cell has no neighbour with a different value than itself (rook's case). It describes patch area and shape simultaneously (more core area when the patch is large and the shape is rather compact, i.e. a square). Because the index is relative, it is comparable among patches with different area.

Percent

0 <= CAI <= 100

Behaviour

CAI = 0 when the patch has no core area and approaches CAI = 100 with increasing percentage of core area within a patch.

tibble

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

lsm_p_core, lsm_p_area,
lsm_c_cai_mn, lsm_c_cai_sd, lsm_c_cai_cv, lsm_c_cpland,
lsm_l_cai_mn, lsm_l_cai_sd, lsm_l_cai_cv
 1 lsm_p_cai(landscape)