Abstract
Climate change poses a critical threat to forest ecosystems, particularly in biodiversity hotspots such as the Western Ghats of Tamil Nadu. This study aims to assess the current and future habitat suitability of dominant tree species representing evergreen, deciduous, and thorn forests using the MaxEnt species distribution model under the SSP2-4.5 climate scenario. A total of 240 geo-referenced occurrence points, along with 19 bioclimatic and topographic variables, were used to predict species-specific habitat changes for the near future (2021-2050), based on downscaled EC-Earth3 CMIP6 climate data. The model projects a significant decline in habitat suitability for evergreen (- 248.72 sq. km) and deciduous (- 720.21 sq. km) forests, while thorn forests are expected to expand by + 968.93 sq. km. District-level analysis highlights hotspots of change, such as Coimbatore (- 50.41 sq. km in evergreen and + 74.46 sq. km in thorn forest) and Erode (- 182.83 sq. km in deciduous and + 184.45 sq. km in thorn forest). These shifts are primarily driven by rising temperatures, increased precipitation seasonality, and changing elevation-related microclimates. The projected expansion of xerophytic thorn forests and concurrent contraction of mesic forests underscores a potential biome-level transition that may reduce biodiversity, alter carbon dynamics, and increase ecological vulnerability. To address these risks, adaptive strategies such as invasive species control, fire management, soil and water conservation, and multi-layered afforestation using native species are recommended. The findings emphasize the need for climate-resilient forest management, community-based conservation, and long-term ecological monitoring. This study offers spatially explicit insights to inform policy and conservation planning under a changing climate.