# lsm_l_mesh: MESH (landscape level) In r-spatialecology/landscapemetrics: Landscape Metrics for Categorical Map Patterns

## Description

Effective Mesh Size (Aggregation metric)

## Usage

  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 lsm_l_mesh(landscape, directions) ## S3 method for class 'RasterLayer' lsm_l_mesh(landscape, directions = 8) ## S3 method for class 'RasterStack' lsm_l_mesh(landscape, directions = 8) ## S3 method for class 'RasterBrick' lsm_l_mesh(landscape, directions = 8) ## S3 method for class 'stars' lsm_l_mesh(landscape, directions = 8) ## S3 method for class 'list' lsm_l_mesh(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

MESH = \frac{∑ \limits_{i = 1}^{m} ∑ \limits_{j = 1}^{n} a_{ij} ^ 2}{A} * \frac{1} {10000}

where a_{ij} is the patch area in square meters and A is the total landscape area in square meters.

The effective mesh size is an 'Aggregation metric'. Because each patch is squared before the sum is calculated and the sum is standardized by the total landscape area, MESH is a relative measure of patch structure. MESH is perfectly, negatively correlated to lsm_c_division.

Hectares

#### Range

cell size / total area <= MESH <= total area

#### Behaviour

Equals cellsize/total area if class covers only one cell and equals total area if only one patch is present.

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

Jaeger, J. A. 2000. Landscape division, splitting index, and effective mesh size: new measures of landscape fragmentation. Landscape ecology, 15(2), 115-130.

lsm_p_area, lsm_l_ta,
lsm_c_mesh
 1 lsm_l_mesh(landscape)