Patch density (Aggregation metric)
lsm_c_pd(landscape, directions = 8)tibble
Raster* Layer, Stack, Brick, SpatRaster (terra), stars, or a list of rasterLayers.
The number of directions in which patches should be connected: 4 (rook's case) or 8 (queen's case).
$$PD = \frac{n_{i}} {A} * 10000 * 100$$ where \(n_{i}\) is the number of patches and \(A\) is the total landscape area in square meters.
PD is an 'Aggregation metric'. It describes the fragmentation of a class, however, does not
necessarily contain information about the configuration or composition of the class. In
contrast to lsm_c_np it is standardized to the area and comparisons among
landscapes with different total area are possible.
Number per 100 hectares
0 < PD <= 1e+06
Increases as the landscape gets more patchy. Reaches its maximum if every cell is a different patch.
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: https://www.umass.edu/landeco/
lsm_c_np,
lsm_l_ta,
lsm_l_pd