Modified Simpson's diversity index (Diversity metric)
lsm_l_msidi(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).
$$MSIDI = -\ln \sum \limits_{i = 1}^{m} P_{i}^{2}$$ where \(P_{i}\) is the landscape area proportion of class i.
MSIDI is a 'Diversity metric'.
None
MSIDI >= 0
MSIDI = 0 if only one patch is present and increases, without limit, as the amount of patches with equally distributed landscape proportions increases
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/
Simpson, E. H. 1949. Measurement of diversity. Nature 163:688
Pielou, E. C. 1975. Ecological Diversity. Wiley-Interscience, New York.
Romme, W. H. 1982. Fire and landscapediversity in subalpine forests of Yellowstone National Park.Ecol.Monogr. 52:199-221
lsm_l_sidi