Predicting climate change impacts on vereda wetland plant species distribution in the Brazilian Cerrado.

Background and aims: The climate crisis is reshaping ecosystems globally, with wetlands, including veredas in the Brazilian Cerrado, among the most vulnerable. Despite their ecological importance, the response of vereda species to climate change remains unclear. This study assessed potential shifts in the distribution of 24 key species under two climate scenarios (SSP2-4.5 and SSP5-8.5) for the period 2061-2080 to understand the impacts on this ecosystem.

Methods: We downloaded 19 bioclimatic variables at a 30 arc-second resolution from the WorldClim database. To avoid multicollinearity, variable selection was performed using Variance Inflation Factor. Future projections were based on the MPI-ESM1-2-HR General Circulation Model. Species distribution models (SDMs) were built using the 'biomod2' R package, incorporating nine algorithms. Model evaluation was conducted using True Skill Statistic and Receiver Operating Characteristic metrics to ensure robust predictions.

Key results: Models demonstrated high reliability, with mean sensitivity (86.83 ± 10.03) and specificity (87.59 ± 7.45). Among 24 species, 13 showed loss of suitable areas under at least one climate scenario, with northeastern Cerrado projected to experience the greatest losses, and expansions occurring along the southern Cerrado-Atlantic Forest border. Desmoscelis villosa showed the greatest losses (-25.86% in SSP2; -25.98% in SSP5), while Xyris tortula exhibited significant gains. Overlap of climatically suitable areas decreased by 1.46% (SSP2) and 0.45% (SSP5), indicating potential range shifts and fragmentation under future scenarios.

Conclusions: Our study highlights that climate change is likely to reshape the distribution of vereda wetland species, with most experiencing a loss of suitable areas. This is particularly concerning given the ecological importance of veredas as biodiversity hotspots and hydrological regulators within the Cerrado. Integrating climate change projections with land-use and conservation strategies will be critical to mitigating these impacts and safeguarding the unique biodiversity of this ecosystem.