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Climate change has increased drought and wildfire frequency in recent decades and poses a significant risk to agricultural lands and private property. Given the negative impact of fires on the livelihoods of farmers, it is crucial to assess the flammability of crop species and find ways of mitigating risk of fire in agricultural lands. We quantify the flammability of 66 tropical species of fiber, food, and spice crops by assessing maximum temperature, burn time, and burned biomass and assessed key leaf traits from a subset of these species to look at the interaction of leaf area (LA) and leaf dry matter content (LDMC) with life form type. We found groundcover, shrubs, and vines to be generally less flammable than canopy and subcanopy plants. We also found LDMC to be a consistent and significant predictor of all three flammability measures regardless of plant life form. Our results equips farmers and policy makers with information for constructing more fire resilient agricultural landscapes and pursuing nature-based solutions to mitigate fire risk, such as by planting green firebreaks with fire retardant species.

Questions: Riverine and associated vegetation communities are periodically affected by floods. However, there have been few quantitative studies on the structural responses of Neotropical tree communities in semi-arid regions to this perturbance. Here, we ask whether flooding regimes and soil attributes affect tree species diversity, composition, community structure, and soil attributes in Neotropical dry forests. Locations: Southeast Brazil. Methods: We sampled 120 forest plots of 400 m² totaling 4.8 ha across four tributaries of the Sao Francisco River with plots situated in areas representing three flooding regimes: (a) annually flooded; (b) occasionally flooded; and (c) never subjected to flooding. Using linear mixed-effects models, we modelled how flooding regime and soil properties (fertility and texture) affect vegetation diversity (species richness), species composition and structural attributes (abundance of individuals, above-ground biomass [AGB], and a community-weighted trait average of multistemness [CWMms]) of these forest plots. Results: Species richness in the annually flooded forests was significantly lower than in occasionally flooded or never flooded forests, in agreement with our models, which showed that flooding regime was a significant predictor for this variable. Flooding regime was a significant predictor of CWMms, with plots in annually flooded forest sites having the highest CWMms values. Soil chemical attributes were a significant predictor of AGB across all plots but not between flooding regime categories. Conclusions: In Neotropical dry forests, environmental filters established by flooding can lead to differences among distinct biomes in vegetation structure, diversity patterns as well as system productivity. Conservation strategies for dry forests should therefore take these factors into consideration. Our study also highlights annually flooded dry forest as a significant component of the regional diversity of dry forests deserving of management attention.

Eremanthus erythropappus is a commercially-important tree which has a long history of exploitation in the Brazilian State of Minas Gerais. The knowledge on the potential geographical distribution of E. erythropappus is therefore critical for the species sustainability. Thus, the aim of this study was to estimate and map current and future ecological niche for E. erythropappus in Minas Gerais. We used the Random Forests algorithm to model the ecological niche for current and future climates scenarios. Our predictions indicate Espinhaço, Mantiqueira, and Canastra mountain ranges as core areas of distribution and forecast drastic reductions in potential areas under all climate scenarios. Based on our results, we highlight that the continual harvesting of naturally-occurring E. erythropappus populations will not be sufficient to supply the market demand. Silviculture practices would likely serve as an economically viable and ecological sustainable alternative to harvesting natural populations.