Post-fire vegetation dynamics and location as main drivers of fire recurrence in Mediterranean forests

Abstract

Fire recurrence is a common phenomenon in Mediterranean forests that interrupts secondary ecosystem successions, hinders regeneration processes, and delays forests from reaching mature stages. To understand the occurrence of successive fires, we investigate the linkages between post-fire vegetation development and subsequent fire events in Eastern Spain during the period 1993–2015. In our study, we analyze annual burnt areas and derive a forest fire recurrence index that we use to explain the factors driving the occurrence of successive fires in previously burnt areas.Based on our results, fire recurrence is largely influenced by post-fire vegetation, as well as by topography and accessibility. Forests dominated by shrubs and sclerophyllous vegetation present higher probabilities of reburnt areas than tree forests. Fire recurrence is time-dependent, with the year of the first fire being an important factor in explaining the proportion of areas burnt twice. Identifying the characteristics and post-fire vegetation types in locations with higher recurrence probabilities can help to pinpoint priority areas and time windows for applying fire prevention and mitigation actions in already vulnerable forests.