Predicting Habitat Suitability and Climate Change Impact on Medicinal plant Dalbergia latifolia and Dillenia pentagyna Using Ecological Niche Modelling

Background: Dalbergia latifolia and Dillenia pentagyna are medicinally significant tree species threatened by habitat loss and climate change. Identifying their current and future suitable habitats is crucial for conservation planning. Methods: We used Maxent (version 3.4.1) ecological niche modelling with 260 occurrence points and 19 bioclimatic variables from the WorldClim dataset to predict the potential distribution of these species in India. Seventy-five percent of the data were used for model training and 25% for testing, with 10 replicates under cross-validation. Future distribution under the 2050 A2a emission scenario was modelled using downscaled climate projections. Results: Maxent performed well, yielding high AUC values of 0.91 for D. latifolia and 0.938 for D. pentagyna, indicating strong predictive performance. The Western Ghats and parts of Central India emerged as the most suitable habitats. Key climatic predictors included minimum temperature of the coldest month and precipitation of the wettest month. Current suitable habitats were estimated at 111,242 km² for D. latifolia and 176,238 km² for D. pentagyna, while future projections indicated a reduction of 38.86% and 40.90% in suitable areas, respectively. Conclusions: Climate change is likely to significantly reduce the suitable habitat for both species by 2050. Conservation strategies should prioritize areas identified through modelling for both in-situ and ex-situ conservation efforts. Ecological niche modelling, as demonstrated here, is a powerful tool for guiding future habitat management and conservation of threatened species.