succniche {primer}

A Four-state model of Successional Dynamics

Description

This is the five-state, two-species model of the succession-niche model, after Pacala and Rees (1998). For use with ode in the deSolve package.

Usage

succniche(t, y, params)

Arguments

t

Argument for the time point at integration

y

A vector of length four, for states, E, M, S, and R.

params

Vector or list of parameters

Value

Returns a list of length one, for use with ode in the deSolve package.

Component 1

vector of the state variable (a scalar for the proportion of sites occupied).

Author(s)

Hank Stevens <[e-mail]>

References

Pacala, S.W. and Rees, M. (1998) Models suggesting field experiments to test two hypotheses explaining successional diversity. The American Naturalist, 152, 729–737.

Stevens, M.H.H. (2009) A Primer of Ecology with R. Use R! Series. Springer.

See Also

levins, compcol, compcolM

Examples

params.suc <- c(a=7, c=0.2, g=.1, m=0.04, D=0)
t=seq(0,50,.1)
init.suc <- c(S=0, E=0.5, M=0.5, R=0.00) # Free space is implicit, F=1-(S+E+M+R).
ccg.out <- data.frame(ode(init.suc, t, succniche, params.suc))
matplot(t, ccg.out[,-1], type="l", ylab="Relative Frequency",
         xlab="Time", ylim=c(0,1) )
legend("right", colnames(ccg.out)[5:2], lty=4:1,  bty="n")