MetaLandSim (version 0.2)

rland.graph: Function to create a random landscape graph

Description

One of the key functions of the package, which allows the creation of random landscapes (represented as graphs) with two categories: habitat patch and non-habitat matrix. The landscapes can be different depending on the parameters chosen.

Usage

rland.graph(mapsize, dist_m, areaM, areaSD, Npatch, disp, plotG)

Arguments

mapsize

Landscape mosaic side length, in meters.

dist_m

Minimum distance between patches (centroid).

areaM

Mean area (in hectares).

areaSD

SD of the area of patches, in order to give variability to the patches area.

Npatch

Number of patches (might be impaired by the dist_m, see the "Note" section).

disp

Species mean dispersal ability, in meters.

plotG

TRUE/FALSE, to show graphic output.

Value

• Returns a list, with the following elements:
  • mapsize
  {Side of the landscape in meters.}
• minimum.distance
  Minimum distance between patches centroids, in meters.
• mean.area
  Mean patch area in hectares.
• SD.area
  Standard deviation of patches area.
• number.patches
  Total number of patches.
• dispersal
  Species mean dispersal ability, in meters.
• nodes.characteristics
  Data frame with patch (node) information (coordinates, area, radius, cluster, distance to nearest neighbour and ID).
• An additional field, colour, has only graphical purposes.

See Also

span.graph, species.graph

Examples

#Example to create a random landscape graph with 60 patches with a mean area 
#of 0.05 hectares. 
#The landscape mosaic is a square with 1000 meters side.
#The species mean dispersal ability is 120 meters (in order to connect the patches).
#A plot with the landscape graph is displayed graphically.

rl1 <- rland.graph(mapsize=1000, dist_m=80, areaM=0.05, areaSD=0.02, Npatch=60, 
			disp=120, plotG=TRUE)