Predicting fire regimes in neotropical savannahs: the influence of fuel traits and environmental factors

Resumen

Fire is a key disturbance structuring savannah ecosystems. Fuel traits are key determinants of fire regimes, but how traits co-vary, whether they are predictable and contribute to explain fire regimes is yet to be rigorously evaluated. To address this gap, we distributed 31 plots across Serra da Canastra National Park, Brazil, following a stratified (by soil class) random sampling, and measured six fuel traits: fuel loads, grass loads, continuity, height, bulk density and bed flammability. For each plot, we also obtained data on climate, canopy cover, soil texture and fire history. Pearson correlation tests, principal component analyses and generalized linear models revealed two main axis of trait variability, one explained by grass biomass in which flammability increased with time since last fire, and a second, explained by woody plant derived material in which flammability decreased with canopy cover and soil clay content. Grass fuel loads were the main predictor of fire incidence in the next two years following sampling. Overall, these results supported the idea that fire regimes are predictable in space and time at the landscape scale and highlight the fundamental roles of fire history, soil and vegetation as drivers of fire regimes in Neotropical savannahs.

Citation: de Lima Dantas, V., Barbosa Ferreira Manzan, W. & Oliveira Arantes, K. 2025. Predicting fire regimes in neotropical savannahs: the influence of fuel traits and environmental factors. Revista Jard. Bot. Nac. Univ. Habana 46 (Número especial 1): 75.

Trabajo presentado en el XIII Congreso Latinoamericano de Botánica. Sesión Ecología, Interacciones, Medio Ambiente y Cambio Climático.