BAT (version 1.1)

sim.spatial: Simulation of species spatial distributions.

Description

Creates artificial communities with given SAD and spatial clustering.

Usage

sim.spatial(n, s, sad = "lognormal", sd = 1, dist = "aggregated",
  clust = 1)

Arguments

n

total number of individuals.

s

number of species.

sad

The SAD distribution type (lognormal, uniform, broken stick or geometric). Default is lognormal.

sd

The standard deviation of lognormal distributions. Default is 1.

dist

The spatial distribution of individual species populations (aggregated, random, uniform or gradient). Default is aggregated.

clust

The clustering parameter (higher values create more clustered populations). Default is 1.

Value

• A matrix of individuals x (species, x coords and y coords).

Details

The spatial distribution of individuals of given species may take a number of forms. Competitive exclusion may cause overdispersion, specific habitat needs or cooperation may cause aggregation and environmental gradients may cause abundance gradients.

Examples

par(mfrow = c(3 ,3))
comm = sim.spatial(100, 9, dist = "uniform")
for(i in 1:9){
	sp <- comm[comm[1] == paste("Sp", i, sep = ""), ]
	plot(sp$x, sp$y, main = paste("Sp", i), xlim = c(0,1), ylim = c(0,1))
}
comm = sim.spatial(1000, 9, sad = "lognormal", sd = 0.5, dist = "aggregated", clust = 2)
for(i in 1:9){
	sp <- comm[comm[1] == paste("Sp", i, sep=""), ]
	plot(sp$x, sp$y, main = paste("Sp", i), xlim = c(0,1), ylim = c(0,1))
}