Contrasting state land and fire use policies condition fire regime seasonality and size in two Central Spain forest landscapes

Abstract

In this article we describe contrasting state land use and fire management policy forest landscape level legacies in two contiguous municipalities of the Gredos mountain range in Central Spain. We employed an exploratory sequential mixed methods approach to collect complementary palynological, dendroecological, municipal level individual fire report and state archive “Ordenación” plan data for the 1850–2021 period. We hypothesize that the variations in land and cultural fire use through time that we have documented contributed to shape significant differences in forest structure and species composition in two municipalities with similar biophysical environments. Higher fire frequency most likely associated with preindustrial era agro-sylvo-pastoral and resin tapping uses, we argue, contributed to maintain, in one site, an open canopy, savanna-like “dehesa”, heterogenous forest landscape of Pinus pinaster, Quercus pyrenaica and grassland patches with low average annual burnt area whereas, conversely, lower fire frequency associated with stricter state fire exclusion policies and prioritization of timber production in the 20th century contributed to the maintenance of a closed canopy, dense, homogeneous Pinus pinaster forest with higher average burnt area in the other site. These findings have important policy implications for European Mediterranean Basin Forest ecosystems where there is an ongoing debate over the social and ecological impacts of 20th century state fire exclusion policies in the context of widespread rural abandonment, tree cover expansion and densification, shrub encroachment in “dehesa” structured forests and the increased frequency of extreme wildfire events in expanding wildland urban interface areas.