Habitat distribution modeling for conservation of Rheum australe D. Don in Himalayas

Abstract

Rheum australe, an important medicinal plant from the Polygonaceae family, is primarily found across the Himalayas. However, due to overharvesting, its population has witnessed a substantial decline. The present study aims to predict the present and future favorable distribution of R. australe in the Himalayan region by employing the Maxent species distribution model. According to the model output, the optimal habitat for cultivating R. australe in the North-West Himalayas spans approximately 75,409 km². However, our projection model for the year 2050 indicates a reduction in this habitat area, showing the most advantageous geographical distribution to be around 59,612 km². While the projected future distribution of R. australe remains largely similar to its current distribution, the model results highlight a decline of 20.94% in the area deemed highly suitable for its growth. The key predictors determining its distribution include Mean Temperature of Coldest Quarter (bio 11), Annual Mean Temperature (bio 1), and Precipitation of the warmest quarter (bio 18).