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<div><p>Most of the world’s mountains are distributed across national boundaries. However, due to the sovereignty of national boundaries, conservation plans between neighboring countries are often uncoordinated. Against the backdrop of impending environmental changes, transboundary mountain ecosystems and biodiversity face significant threats. This study employs the MaxEnt model, leveraging data on climate, topography, landscape, and human activities to predict potential distribution areas for mammals and birds, aiming to identify biodiversity hotspots (BHs) and analyze their distribution mechanisms in the Altai Mountains transboundary region (AMTR). Results indicate that BHs are primarily located near the Russian-Mongolian border, significantly influenced by climate variables, elevation, and human activities. The study also highlights changes in key habitat types (KHTs), particularly transitions between grassland and bareland, and the impact of climate-driven land cover change on the distribution of BHs. Furthermore, the research evaluates the coverage of protected areas and emphasizes the importance of identifying key biodiversity areas (KBAs) and establishing transboundary corridors for enhanced species protection and future environmental change adaptation. The findings underscore the necessity of transboundary cooperation and focused strategies for biodiversity conservation to mitigate the adverse effects of climate change and human activities.</p></div>