Disentangling Vereda Wetlands determinants across a wide geographic extent

Veredas are wetlands from the Brazilian Cerrado hotspot biome, noted for their rich biodiversity and ecosystem services, including water provision and carbon storage. They are characteristically found in gently sloping, low-lying valleys, where the water table emerges and flows slowly. However, their distribution and abiotic drivers remain poorly understood. Thus, we tested the hypotheses that water availability (i.e., precipitation) has a positive effect on Veredas ’ distribution, while steep terrains (i.e., slope variance) have a negative effect. We used a grid-based approach to capture fine-scale variation across the Triângulo Mineiro and Alto Paranaíba (TMAP) region. We also investigated the effects of multiple climate, terrain, and soil variables in explaining Veredas occurrence. Our results supported the hypothesis regarding water availability, as the precipitation of the driest month positively influenced the probability of Veredas occurrence, explaining 5.4% of the variance. Furthermore, our results supported the hypothesis regarding slope variance, as it negatively influenced both the probability of occurrence and the abundance of Veredas , explaining 8.8% and 9.4% of the variance, respectively. Microregions with Veredas differed from those without across 23 terrain, soil, and climatic variables, indicating that additional predictors contribute to explaining Veredas ’ distribution. In contrast with previous descriptive, climate-zone comparisons, this study represents the first hypothesis-driven, landscape-scale evaluation of the determinants of Veredas occurrence, suggesting that water availability recharges the water table and flat terrains facilitate the formation of hydromorphic soil and slow water drainage. These findings provide a mechanistic basis for identifying priority areas for conservation and water security, highlighting the need for management strategies that anticipate the vulnerability of Veredas to ongoing climate change in the Cerrado biome.