Biodiversity hotspot assessment in the Altai Mountains transboundary region based on Mammals and Aves

is still room for regional parties to improve their efforts in AMTR to better cope with future environmental changes. To enhance the effectiveness of protected areas and expand their coverage, several strategies can be implemented. Enhancing connectivity by establishing ecological corridors between existing PAs is crucial for facilitating species migration and genetic exchange. This can be achieved by identifying and protecting key migration routes, especially those connecting trans- boundary areas [50]. Strengthening legal frameworks is also essential, which involves imple- menting stronger legal protections for PAs and enhancing enforcement mechanisms to prevent illegal activities such as poaching and habitat destruction. Another critical strategy is community involvement. Engaging local communities in con- servation efforts through education and providing incentives for sustainable land use practices can help in reducing human-wildlife conflicts and promoting coexistence. Regular monitoring and research are also vital. Regular monitoring of biodiversity and ecological conditions within PAs can inform adaptive management strategies. Investing in research to understand the impacts of climate change and human activities on biodiversity can provide valuable insights for effective conservation planning. Securing adequate funding and resources is fundamental for the management and expan- sion of PAs. This includes leveraging international funding mechanisms and partnerships to mobilize the necessary resources for these efforts. By implementing these strategies, regional

parties can improve their conservation efforts in AMTR and better cope with future environ- mental changes, thereby ensuring the resilience and sustainability of this ecologically signifi- cant region. Identification of key biodiversity areas and transboundary corridors In order to further promote the protection of threatened species and cope with future environ- mental changes, it is essential to identify key biodiversity areas (KBAs) and transboundary cor- ridors in various regions and promote transboundary protection [51–53]. We reclassified the interior from the perspective of each region (by 0~20%, 20%~50%, >50% within the region) to determine the richness level within each region and better identify the KBAs and key PAs. Areas with high richness (HR) in each region are considered priorities for biodiversity conser- vation [34, 54] (S2 Table in S1 File). This classification provides a reference for relevant parties to focus their protection efforts. We found that most KBAs and protected areas have good cov- erage of KABs of threatened mammals (TM) (>30%), but the protected areas (PAs) coverage of KBAs of TM in RAR is only 22.04%. For the PAs coverage of KBAs of threatened aves (TA), only KAR exceeds 30% (Fig 10). This indicates that there is still room for improving protected area settings in each district in the future. Since mammals, especially large mammals, often undergo long-distance migrations [55, 56], transboundary migration often occurs in mountainous regions and is affected by human

factors such as border walls or physical jurisdiction [50]. Identifying transboundary migration corridors is critical for the conservation of threatened mammals. Therefore, we constructed an ecological resistance surface (S Table 3 in S1 File) based on the TM distribution tendency using five factors such as elevation and landscape, and input the KBAs of TM and resistance into the Linkage Mapper toolbox (https://linkagemapper.org/, see S4 for detailed operation in S1 File). In AMTR, 25 corridors were identified (Fig 11), including 14 transboundary corri- dors. There are 3 between Russia and Kazakhstan, 1 between Russia and Mongolia, 8 between China and Mongolia, and 2 between Russia and China and Kazakhstan. The identification of transboundary corridors provides a reference for relevant parties to protect TM, especially by pointing out feasible locations for dismantling unreasonable border PLOS ONE Biodiversity hotspot assessment in the Altai Mountains transboundary region PLOS ONE | https://doi.org/10.1371/journal.pone.0314075 December 4, 2024 14 / 20