Relative Contributions of Forest Vegetation, Land Cover, Topography and Climate in Explaining Fire Regime Patterns (1974–2005) in Peninsular Spain

The relevance of forest fires as a major disturbance factor in vegetation composition, dynamics, and structure is increasing in several ecosystem types. In order to develop adaptation procedures and to strengthen the resilience under future altered fire regimes, it is important to gain a greater understanding of the factors involved in regional fire regimes. This paper evaluates the relative contributions of forest vegetation, land cover, topography, and climate in explaining the fire regime patterns. The analyses were performed independently for 15 territory types delimited according to potential vegetation criteria. Redundancy analysis was used to enable the simultaneous ordination of the response (fire regime) and the explanatory variables. The results reveal important differences among the 15 territories. The explained variance ranged from low to medium depending on the territory. However, for the five territories with greatest fire incidence, the variance explained was more than 39%. The proportion of territory covered by forest (derived from land cover information) was found to be the most relevant variable. Unexpectedly, the type of forest vegetation (derived from forest inventory data) appears to have played, at least in this approach and for some territories, a secondary role in explaining the registered fire regime patterns.