Climate models predict a divergent future for the medicinal tree Boswellia serrata Roxb. in India

Abstract

Predicting the distribution of future climatically suitable habitat areas is crucial for the long-term success of species conservation and management plans. However, generating accurate predictions may be difficult as the assumptions and variables used in the construction of different climate scenarios may result in divergent trajectories of change. Nevertheless, generating species distribution models under multiple scenarios is helpful in selecting an optimal solution for practical applications. In this study, we compare the current distribution of climatically suitable areas of a threatened medicinally important tree, Boswellia serrata Roxb. in India with its distribution in the year 2050 modeled using two climate change scenarios - IPSL-CM5A-LR and NIMR-HADGEM2-AO - each represented by four representative concentration pathways (RCPs). Maximum entropy modeling with 19 bioclimatic variables was used to construct the climatic niche of B. serrata for predictions of present and future climatically suitable areas within India. The study revealed that annual mean temperature, mean temperature of wettest quarter and driest quarter, precipitation seasonality, and precipitation of wettest quarter potentially influence the distribution of the species. After thresholding, the model showed that ∼21.95% of the geographical area in India is presently climatically suitable for the species. The IPSL-CM5A-LR and NIMR-HADGEM2-AO climate models revealed contrasting distribution scenarios of climatically suitable areas in India. However, irrespective of these climate models, the four RCPs predict a consistent decrease in suitable area with increases in climatic harshness. Substantial area in peninsular India is expected to lose climatic suitability in 2050, though new areas are also predicted to become climatically suitable. We suggest long-term conservation strategies for B. serrata be prioritized within future areas that are projected to retain climatic suitability.