Alpine endemism under threat: Ecological patterns and conservation strategies in the changing Himalayas

Mountains are vital for biodiversity and endemism, particularly in alpine environments threatened by climate change. Most studies overlook endemic species, which are more vulnerable to climate variability and instability because of their narrow biological niches. This research examines the diversity and distribution of endemic species in the Western Himalayas, focusing on edaphic factors and altitude across three belts: the lower altitudinal belt (LAB), middle altitudinal belt (MAB), and upper altitudinal belt (UAB). Field sampling from 425 quadrats, spanning from 3000-4400 m, identified 102 endemic species from 68 genera and 31 families. Species richness peaked in the UAB (4000-4200 m), averaging 18.14 ± 6.18 species, demonstrating a positive correlation between elevation and endemic richness. Hemicryptophytes were prevalent, with microphylls being the most common leaf type. The study revealed that 58.8% of the endemic species are distributed across the broader Himalayan region, while 41.2% are restricted to the Western Himalayas. Canonical Correspondence Analysis (CCA) indicated strong ties between endemic species and environmental factors, with soil organic carbon (SOC) identified as a primary determinant. Additionally, a statistically significant decline in soil pH with elevation (p = 0.0049) negatively affected species richness (p = 0.0127). Edaphic variations influence species distribution, and conservation assessments highlighted the UAB as the zone with the highest number of endangered species. The results of this study may aid in formulating effective conservation measures to safeguard the valuable endemic flora of the Himalayan alpine zone.