A minimal model for forest fire regimes

We show in this article how the characteristics of fire recurrence in fores ts can be theoretically derived from simple information concerning forest m orphology. The task is accomplished by means of a minimal model encapsulati ng a few assumptions on the interactions between overstory and understory s pecies and on the mechanisms of fire development and transmission. The main difference with other models for fire prediction and simulation is that, h ere, fire is an endogenous variable with purely deterministic dynamics. Nev ertheless, the analysis shows that fire recurrence can be chaotic for param eter values corresponding to Mediterranean forests. By contrast, the model shows that boreal forests and savannas have the tendency to experience peri odic fires. These general results are in agreement with the studies carried out on many different forests in this century.