Ecological vulnerability and driving factors in the himalayan transboundary landscape under global climate change

Climate change and human activities are placing significant pressure on the carrying capacity of the Himalayan alpine ecosystem. This study focuses on seven transboundary protected areas and national parks in the Himalayas, including China's Everest National Nature Reserve and Nepal's Sagarmatha National Park, Manaslu Conservation Area, Langtang National Park, Gauri Sankar Conservation Area, Makalu Barun National Park, and Kanchenjunga Conservation Area. We used the Vulnerability Scoping Diagram (VSD) model to assess ecological vulnerability, analyzing land use changes and landscape patterns from 2000 to 2020 to identify key drivers of landscape changes. The fragmentation of ecological landscapes initially increased and then decreased, with values of 4.05, 3.99, and 3.86 observed, indicating a general reduction in regional ecological vulnerability. The south slope demonstrated lower ecological vulnerability than the north slope. Key factors influencing patch density included annual average temperature, population density, and annual precipitation. Annual precipitation, temperature, and the normalized vegetation index were the primary drivers of the largest patch index. The landscape shape index was most affected by precipitation, vegetation index, and slope, while the spread index was primarily influenced by precipitation and slope. The homogeneity index was most strongly related to annual precipitation, vegetation index, and normalized water index. This study provides a representative case for transboundary cooperation in ecological conservation, offering insights into sustainable development strategies for cross-border regions in the Himalayas.