Climate change poses a severe threat to global biodiversity, with many species facing extinction due to their inability to adapt quickly to changing environmental conditions. Among these is Illicium griffithii, an endangered tree species indigenous to the Himalayan region, particularly in the state of Arunachal Pradesh, India. This study reveals the impact of climate variables on the current and future distribution of I. griffithii, employing an ensemble modeling approach that integrates five species distribution models (SDMs).
The research aims to identify key environmental factors influencing the distribution of I. griffithii and predict its potential distribution under current and future climatic scenarios, specifically the Shared Socio-economic Pathways (SSP) SSP245 and SSP585. The study encompasses the use of fifteen environmental variables, including bioclimatic factors, soil properties, and topographical aspects, to develop a robust predictive model of the species’ habitat suitability.
Currently, the suitable habitat for I. griffithii covers an area of approximately 722.72 km², primarily found in the West Kameng, Tawang, and East Kameng districts. Specifically, West Kameng contributes a significant 82.03% of the total suitable area at 592.83 km². The study highlights that the current distribution of I. griffithii is predominantly influenced by factors such as isothermality, nitrogen content in the soil at a depth of 0–5 cm, clay content in the same depth, and precipitation seasonality, accounting for a cumulative influence of 42.6%.
The ensemble model utilized in this study attained an accuracy with an Area Under the Curve (AUC) value of 0.94 and a True Skill Statistic (TSS) of 0.83, demonstrating exceptional performance in predicting habitat suitability.
However, the projections for the future scenarios indicate a concerning decline in the highly suitable areas for I. griffithii. Specifically, under the SSP585 climate scenario for the period of 2041 to 2060, the area of highly suitable habitat is predicted to shrink by over 5.05%, decreasing from 722.72 km² to 686.25 km². Such declines emphasize the vulnerability of I. griffithii under ongoing climate change.
This research underscores the urgent need for conservation strategies to mitigate the impacts of climate change on the distribution of I. griffithii. Proposed actions include habitat restoration efforts, assisted migration, and ex situ conservation strategies to support this vulnerable species. Local forest managers are encouraged to prioritize the conservation of suitable habitats, particularly within West Kameng, Tawang, and East Kameng districts.
In conclusion, the findings from this study provide crucial insights into the sustainability of I. griffithii's populations in the face of climate change, suggesting that immediate and targeted conservation strategies are essential for ensuring its long-term survival in its natural habitat. The study serves as a call to action for conservationists and policymakers to implement adaptive management strategies that will safeguard not only I. griffithii but also the rich biodiversity of the Himalayan region.
