Comprehensive impacts of national park construction from the multi-dimensional perspective of ecological-production-living functions: a case study of Qilian Mountains grassland ecosystem, China

National parks are widely recognized for their crucial roles in protecting biodiversity, maintaining grassland ecosystem functions, and ensuring ecological security. However, these protective effects are not always immediate or consistent across regions because they depend on resource resilience, spatial heterogeneity, climatic conditions, policy implementation, and functional interactions. Understanding the impact of national parks on grassland functions is essential for guiding the effective design and management of protected areas. We evaluated the impact of national park construction in the Qilian Mountains (QLM) on grasslands, considering ecological, production, and living functions (EPLFs). We applied spatial analysis, trend analysis, and self-organizing mapping to examine the spatiotemporal dynamics of the grassland EPLFs in the QLM. Regression analysis was also employed to determine the comprehensive impact of national parks on grassland EPLFs. From 2012 to 2022, grassland EPLFs in the QLM showed a stable but heterogeneous spatial pattern with an overall decreasing trend. Ecological functions were generally stronger than production and living functions, which declined more inside the national park. Grassland EPLF bundles were mainly dominated by ecological-living and ecological-production-living types, showing a clear shift toward the latter. This indicates that national park construction makes grassland EPLFs more integrated. Overall, areas outside the park were more strongly impacted. We propose strategies to balance ecological protection and human needs for sustainable grassland management in the QLM. These findings provide theoretical support for national park construction and grassland management optimization.