Located at an average elevation of approximately 2000 m, the Minjiang River Basin (MJB), a key tributary of the Upper Yangtze River, straddles the Western Sichuan Plateau and the Sichuan Basin. Vegetation here is crucial for human life, providing oxygen and energy. However, the influence of climatic variables, human activities, and rugged terrain on vegetation vitality is still debated. This study mainly leverages data from the Normalized Difference Vegetation Index (NDVI), meteorological stations data, and land use data. Analytical techniques include trend analysis, partial correlation coefficient analysis (PCC), principal component analysis (PCA), and partial least squares structural equation modeling (PLS-SEM). Results indicate a stable upward trend in vegetation growth with minimal fluctuations, with a growth rate of 0.95 × 10⁻³/a (p < 0.01). PCC analysis shows a positive correlation between NDVI and key climatic elements in over 60% of the area. The areas with significant vegetation growth had the highest average PCC. PCA and PLS-SEM identify temperature and precipitation as primary growth drivers, while elevation and land use intensity hinder growth. The MJB landscape reveals thresholds and tipping points, with specific temperature and precipitation benchmarks varying by elevation, delineating the boundary between flourishing vegetation and growth inhibition.

Under the dual pressures of climate change and anthropogenic activities, the sustainability of the fragile ecosystem on the Qingzang Plateau has garnered considerable attention. This study, taking the Yarlung Tsangpo River, Lhasa River, and Nianchu River Basin (YNL) of Xizang as a case study, systematically assesses the spatiotemporal evolution of its ecosystem services from 2000 to 2020. It reveals a critical dynamic: while regional ecosystem services have shown an overall improving trend over the past two decades, driven jointly by a warmer and wetter climate and ecological engineering projects, the adverse impacts of human activities have intensified significantly, posing an emerging and growing threat to regional ecological security. Based on the InVEST model, this research quantifies four key services and constructs a Comprehensive Ecosystem Service (CES) index to evaluate the overall ecosystem function. Subsequently, an integrated Principal Component Analysis and Partial Least Squares Structural Equation Modeling (PCA-PLS-SEM) analytical framework is employed to decouple the complex pathways driving CES successfully. The results confirm that climate and topography are the fundamental natural drivers determining the spatial pattern of ecosystem services, which is characterized as being high in the east and low in the west. The core contribution of this study lies in its quantitative identification of the coexisting reality of “ecological improvement” and “development pressure” in the region. It emphasizes that future management strategies must urgently shift from a static conservation approach to an integrated paradigm capable of proactively addressing human–land contradictions. This provides a critical scientific basis for safeguarding China’s national ecological security barrier.

Cropland is crucial for food production, food security, and economic stability, especially in high-altitude Tibetan regions where it is limited. This study investigates the spatiotemporal changes and driving factors of cropland in the Yarlung Zangbo River Basin (YZRB) from 2000 to 2020. Using land use transfer matrices, center of gravity models, standard deviation ellipses, the Patch-generating Land Use Simulation (PLUS) model, and Partial Least Squares Structural Equation Modeling (PLS-SEM), it explores cropland dynamics and predicts land use for 2030. Results show the following: (1) Between 2000 and 2020, the area of cropland entering the basin exceeded that leaving, mainly concentrated in the middle and lower reaches, with a dynamic degree of 0.97%. The proportion of cropland increased from 1.28% in 2000 to 1.52% in 2020. (2) The center of gravity shifted northwest (2000–2005), southeast (2005–2015), and northwest again (2015–2020). (3) Factors like elevation, temperature, precipitation, population density, and GDP correlated with cropland changes. Natural factors positively affected cropland expansion, while socioeconomic and proximity factors indirectly inhibited it. (4) The 2030 cropland conservation scenario in the PLUS model ensures cropland security, ecological protection, and controlled construction land expansion, aligning with the Sustainable Development Goals. Targeted cropland conservation measures can effectively promote sustainable land use and ecological security in the Yarlung Zangbo River Basin.