Calculate patch and landscape statistics
MK_Fragmentation( patches, edge_distance = 500, min_patch_area = 100, landscape_area = NULL, area_unit = "km2", perimeter_unit = "km", plot = FALSE, write = NULL )
Arguments
| patches | Object of class sf, sfc, sfg or SpatialPolygons. Individual patches, the shapefile must be in a projected coordinate system. |
|---|---|
| edge_distance | Numeric. Distance to edge in meters. Default equal 500 m (Haddad et al. 2015) |
| min_patch_area | Numeric. Minimum patch area. Default equal 100 km2 (Haddad et al. 2015) |
| landscape_area | Numeric. Total landscape area in km2 (optional). If NULL the total patch area will be used. |
| area_unit | character. You can set an area unit (e.g., "km2", "cm2", "m2", "ha"; see Makurhini::unit_convert). Default equal to square kilometers "km2". |
| perimeter_unit | character. You can set a perimeter unit (e.g., "km", "cm", "m", "ha"; see Makurhini::unit_convert). Default equal to kilometers "km". |
| plot | Logical. Basic histograms and core area - edge map. |
| write | Character. Write the tables, shapefile and and plots. It's necessary to specify the path and prefix, for example, to save in the path "C:/Folder" with the prefix "Fragmentation": "C:/Folder/Fragmentation". |
Value
Patch and landscape statistics:
1) Patches Area in square kilometers.
2) Number patches.
3) Mean size of patches.
4) Number of patches smaller than 100 km2 or another minimum patch area.
5) Area in square kilometers of patches smaller than 100 km2 or another minimum patch area.
6) Total edge.
7) Edge density.
8) Total core area (km2; considering a distance to edge of 500 m).
9) Total core area.
10) Core percent.
11) Edge percent.
12) Cority index. It is a measure of fragmentation with respect to a distance from the core area of 500 m (Haddad et al., 2015), where a value of 1 indicates a landscape without fragmentation.
13) Shape Index. A simple shape metric that takes values from 1 (perfectly compact) to infinity is derived by dividing the perimeter by the perimeter of a circle of the same area.
14) Fractal dimension.
15) Effective Mesh Size.
References
McGarigal, K., S. A. Cushman, M. C. Neel, and E. Ene. 2002. FRAGSTATS: Spatial Pattern Analysis Program for Categorical Maps. Computer software program produced by the authors at the University of Massachusetts, Amherst. Available at the following web site:
www.umass.edu/landeco/research/fragstats/fragstats.html.
Haddad et al. (2015). Science Advances 1(2):e1500052. DOI: 10.1126/sciadv.1500052.
Examples
#> [1] 142fragmentation <- MK_Fragmentation(patches = vegetation_patches, edge_distance = 1000, plot = TRUE)#Table fragmentation$`Summary landscape metrics (Viewer Panel)` #Shapefile fragmentation$`Patch statistics shapefile`#> Simple feature collection with 142 features and 9 fields #> Geometry type: POLYGON #> Dimension: XY #> Bounding box: xmin: 3340120 ymin: 322869.6 xmax: 3739484 ymax: 696540.5 #> CRS: +proj=lcc +lat_1=17.5 +lat_2=29.5 +lat_0=12 +lon_0=-102 +x_0=2500000 +y_0=0 +datum=WGS84 +units=m +no_defs #> First 10 features: #> id Area CA CAPercent Perimeter EdgePercent PARA ShapeIndex #> 1 1 4195.5691 3028.5557 72.1846 1412.046 27.8154 2.9713 8212.7666 #> 2 2 60.2227 0.3580 0.5945 167.982 99.4055 0.3585 117.0545 #> 3 3 48.8665 0.0000 0.0000 127.049 100.0000 0.3846 79.7484 #> 4 4 15.1875 2.4127 15.8861 18.536 84.1139 0.8194 6.4864 #> 5 5 33.2716 2.3258 6.9903 55.038 93.0097 0.6045 28.5066 #> 6 6 53.1344 0.0403 0.0758 111.123 99.9242 0.4782 72.7339 #> 7 7 83.8417 6.4824 7.7317 121.275 92.2683 0.6913 99.7118 #> 8 8 17.3865 0.0463 0.2663 33.798 99.7337 0.5144 12.6544 #> 9 9 18.0369 0.9129 5.0613 25.755 94.9387 0.7003 9.8217 #> 10 10 36.3359 7.4507 20.5051 36.972 79.4949 0.9828 20.0118 #> FRAC geometry #> 1 1.4065 POLYGON ((3676911 589967.3,... #> 2 1.8241 POLYGON ((3558044 696202.5,... #> 3 1.7785 POLYGON ((3569169 687776.4,... #> 4 1.1273 POLYGON ((3547317 685713.2,... #> 5 1.4961 POLYGON ((3567471 684357.4,... #> 6 1.6735 POLYGON ((3590569 672451.7,... #> 7 1.5407 POLYGON ((3570789 670959.4,... #> 8 1.4946 POLYGON ((3440118 666273.2,... #> 9 1.2877 POLYGON ((3451637 671232.4,... #> 10 1.2380 POLYGON ((3444396 671675.7,...
