English

Coexistence of grass, saplings and trees in the Staver-Levin forest model

Probability 2015-10-29 v5

Abstract

In this paper, we consider two attractive stochastic spatial models in which each site can be in state 0, 1 or 2: Krone's model in which 0={}={}vacant, 1={}={}juvenile and 2={}={}a mature individual capable of giving birth, and the Staver-Levin forest model in which 0={}={}grass, 1={}={}sapling and 2={}={}tree. Our first result shows that if (0,0)(0,0) is an unstable fixed point of the mean-field ODE for densities of 1's and 2's then when the range of interaction is large, there is positive probability of survival starting from a finite set and a stationary distribution in which all three types are present. The result we obtain in this way is asymptotically sharp for Krone's model. However, in the Staver-Levin forest model, if (0,0)(0,0) is attracting then there may also be another stable fixed point for the ODE, and in some of these cases there is a nontrivial stationary distribution.

Keywords

Cite

@article{arxiv.1401.5220,
  title  = {Coexistence of grass, saplings and trees in the Staver-Levin forest model},
  author = {Rick Durrett and Yuan Zhang},
  journal= {arXiv preprint arXiv:1401.5220},
  year   = {2015}
}

Comments

Published at http://dx.doi.org/10.1214/14-AAP1079 in the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)