landscapemetrics (version 1.4.4)

lsm_l_prd: PRD (landscape level)

Description

Patch richness density (Diversity metric)

Usage

lsm_l_prd(landscape, directions)

# S3 method for RasterLayer lsm_l_prd(landscape, directions = 8)

# S3 method for RasterStack lsm_l_prd(landscape, directions = 8)

# S3 method for RasterBrick lsm_l_prd(landscape, directions = 8)

# S3 method for stars lsm_l_prd(landscape, directions = 8)

# S3 method for list lsm_l_prd(landscape, directions = 8)

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).

Value

tibble

Details

$$PRD = \frac{m} {A} * 10000 * 100 $$ where \(m\) is the number of classes and \(A\) is the total landscape area in square meters.

PRD is a 'Diversity metric'. It is one of the simplest diversity and composition measures. In contrast to lsm_l_pr, it is a relative measure and following, comparable among landscapes with different total landscape areas.

Units

Number per 100 hectares

Range

PR > 0

Behaviour

Approaches PRD > 1 when only one patch is present and the landscape is rather large. Increases, without limit, as the number of classes increases and the total landscape area decreases.

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

Examples

Run this code
# NOT RUN {
lsm_l_prd(landscape)

# }

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