College of Earth and Environmental Sciences, Center for Glacier and Desert Research, Scientific Observing Station for Desert and Glacier, Lanzhou University, Lanzhou, 730000, China.
J Environ Manage. 2024 Aug;366:121655. doi: 10.1016/j.jenvman.2024.121655. Epub 2024 Jul 8.
Climate change is threatening fragile alpine ecosystems and their resident ungulates, particularly the wild yak (Bos mutus) that inhabits alpine areas between the tree line and glaciers on the Tibetan Plateau. Although wild yaks tend to shift habitats in response to changes in climatic factors, the precise impacts of climate change on their habitat distribution and climate refugia remain unclear. Based on over 1000 occurrence records, the maximum entropy (MaxEnt) algorithm was applied to simulate habitat ranges in the last glacial maximum (LGM), Mid-Holocene, current stage, and three greenhouse gas emission scenarios in 2070. Three habitat patches were identified as climate refugia for wild yaks that have persisted from the LGM to the present and are projected to persist until 2070. These stable areas account for approximately 64% of the current wild yak habitat extent and are sufficiently large to support viable populations. The long-term persistence of these climate refugia areas is primarily attributed to the unique alpine environmental features of the Tibetan Plateau, where relatively stable arid or semi-arid climates are maintained, and a wide range of forage resource supplies are available. However, habitat loss by 2070 caused by insufficient protection is predicted to lead to severe fragmentation in the southeastern and northwestern Kunlun, Hengduan, central-western Qilian, and southern Tanggula-northern Himalaya Mountains. Habitat disturbance has also been caused by increasing anthropogenic effects in the southern Tanggula and northern Himalaya Mountains. We suggest that sufficient protection, transboundary cooperation, and community involvement are required to improve wild yak conservation efforts. Our combined modeling method (MaxEnt-Zonation-Linkage Mapper-FRAGSTAT) can be utilized to identify priority areas and linkages between habitat patches while assessing the conservation efficiency of protected areas and analyzing the coupled relationship between climate change and anthropogenic impacts on the habitat distribution of endangered species.
气候变化正在威胁脆弱的高山生态系统及其居住的有蹄类动物，特别是栖息在青藏高原上林线和冰川之间高山地区的野生牦牛（Bos mutus）。尽管野生牦牛往往会因气候因素的变化而改变栖息地，但气候变化对其栖息地分布和气候避难所的确切影响仍不清楚。基于超过 1000 个发生记录，我们应用最大熵（MaxEnt）算法模拟了末次冰盛期（LGM）、中全新世、当前阶段以及 2070 年三种温室气体排放情景下的野生牦牛栖息地范围。确定了三个栖息地斑块作为野生牦牛的气候避难所，这些避难所从末次冰盛期一直持续到现在，并预计将持续到 2070 年。这些稳定区域约占当前野生牦牛栖息地范围的 64%，足以支持有生存能力的种群。这些气候避难所区域的长期存在主要归因于青藏高原独特的高山环境特征，那里维持着相对稳定的干旱或半干旱气候，并且有广泛的饲料资源供应。然而，到 2070 年，由于保护不足导致的栖息地丧失预计将导致昆仑山脉东南部和西北部、横断山脉、祁连山中西部和喜马拉雅山脉北部严重破碎化。人类活动的增加也导致了青藏高原南部和喜马拉雅山脉北部的栖息地受到干扰。我们建议，需要充分的保护、跨界合作和社区参与，以改善野生牦牛的保护工作。我们的综合建模方法（MaxEnt-Zonation-Linkage Mapper-FRAGSTAT）可用于识别优先区域和栖息地斑块之间的联系，同时评估保护区的保护效率，分析气候变化和人为影响对濒危物种栖息地分布的耦合关系。
