Endemic and Endangered Vascular Flora of Kazakhstan’s Altai Mountains: A Baseline for Sustainable Biodiversity Conservation

The Altai Mountains of Kazakhstan form a critical part of the Altai-Sayan Ecoregion, one of Central Asia’s most important centers of plant endemism and biodiversity. However, this fragile mountain ecosystem is increasingly threatened by climate change, unsustainable land use, and habitat degradation. This study provides the first comprehensive checklist of rare, endemic, and endangered vascular plant species of Kazakhstan’s Altai, integrating herbarium data and spatial analyses to support regional conservation and sustainability goals. A total of 65,540 herbarium specimens from eight major collections were reviewed, and species identifications were verified using national and international databases. In total, 230 rare and endangered species were recorded, including 73 strict endemics. Species were assessed using IUCN Red List categories, and their distributions analyzed with GIS and hierarchical clustering tools. The results revealed a high concentration of threatened species in the Ivanovskiy, Narym, and Azutau ridges. Notably, 127 species were assessed for rarity status for the first time, with families such as Poaceae and Orchidaceae disproportionately represented. The study highlights substantial gaps in current conservation frameworks, as many species remain in the “Data Deficient” category, and some highly threatened taxa occur outside protected areas. These findings provide essential baseline data to inform the expansion of protected zones, guide national Red Book updates, and support targeted ex situ conservation. By prioritizing biodiversity-rich areas and incorporating plant rarity data into spatial planning, this research contributes directly to long-term sustainability and ecosystem resilience strategies in Kazakhstan’s mountainous regions.