lsm_c_cohesion: COHESION (class level)

Description Usage Arguments Details Value References See Also Examples

Description

Patch Cohesion Index (Aggregation metric)

Usage

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lsm_c_cohesion(landscape, directions)

## S3 method for class 'RasterLayer'
lsm_c_cohesion(landscape, directions = 8)

## S3 method for class 'RasterStack'
lsm_c_cohesion(landscape, directions = 8)

## S3 method for class 'RasterBrick'
lsm_c_cohesion(landscape, directions = 8)

## S3 method for class 'stars'
lsm_c_cohesion(landscape, directions = 8)

## S3 method for class 'list'
lsm_c_cohesion(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).

Details

COHESION = 1 - (\frac{∑ \limits_{j = 1}^{n} p_{ij}} {∑ \limits_{j = 1}^{n} p_{ij} √{a_{ij}}}) * (1 - \frac{1} {√{Z}}) ^ {-1} * 100

where p_{ij} is the perimeter in meters, a_{ij} is the area in square meters and Z is the number of cells.

COHESION is an 'Aggregation metric'. It characterises the connectedness of patches belonging to class i. It can be used to asses if patches of the same class are located aggregated or rather isolated and thereby COHESION gives information about the configuration of the landscape.

Units

Percent

Ranges

0 < COHESION < 100

Behaviour

Approaches COHESION = 0 if patches of class i become more isolated. Increases if patches of class i become more aggregated.

Value

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

Schumaker, N. H. 1996. Using landscape indices to predict habitat connectivity. Ecology, 77(4), 1210-1225.

See Also

lsm_p_perim, lsm_p_area,
lsm_l_cohesion

Examples

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r-spatialecology/landscapemetrics documentation built on May 20, 2019, noon