sim.spatial {BAT} | R Documentation |
Creates artificial communities with given SAD and spatial clustering.
sim.spatial( n, s, sad = "lognormal", sd = 1, distribution = "aggregated", clust = 1 )
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. |
distribution |
The spatial distribution of individual species populations (aggregated, random, uniform or gradient). Default is aggregated. |
clust |
The clustering parameter if distribution is either aggregated or gradient (higher values create more clustered populations). Default is 1. |
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.
A matrix of individuals x (species, x coords and y coords).
par(mfrow = c(3 ,3)) comm = sim.spatial(100, 9, distribution = "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, distribution = "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)) }