Splitting index (Aggregation metric)
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
$$SSPLIT = \frac{A^2} {\sum \limits_{i = 1}^{m} \sum \limits_{j = 1}^{n} a_{ij}^2}$$ where \(a_{ij}\) is the patch area in square meters and \(A\) is the total landscape area.
SPLIT is an 'Aggregation metric'. It describes the number of patches if all patches the landscape would be divided into equally sized patches.
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
Jaeger, J. A. 2000. Landscape division, splitting index, and effective mesh size: new measures of landscape fragmentation. Landscape ecology, 15(2), 115-130.