Spatiotemporal variation of net primary productivity and its climate-landscape-human drivers in the Yellow River Basin of Inner Mongolia

Abstract

The Yellow River Basin (YRB) in Inner Mongolia serves as an important ecological barrier and a major carbon sink within northern China, and is facing a considerable ecological vulnerability and substantial pressures due to climate change, urbanization, and agricultural development. This study takes a landscape architecture perspective to explore the spatio-temporal dynamics of net primary productivity (NPP) and the factors that drive these changes. The goal is to reduce ecological fragility, enhance carbon storage, and meet development needs. Using MODIS NPP and GPP products, we quantified NPP fluctuations and combined multi-scale spatial analysis, landscape pattern indices, and principal component analysis (PCA) to examine landscape evolution. We used correlation analysis, redundancy analysis, and a partial correlation–partial derivative coupling model to evaluate the impacts of climatic variables, landscape fragmentation, and human activities on Net Primary Productivity (NPP). The results show that regional NPP has generally increased, spreading from east to southwest with clear differences across various landscape types. Grassland remained dominant, covering over 60% of the area, while construction land expanded, and sandy land decreased. Landscape patterns became less fragmented and more connected. Climate factors were the main positive drivers of NPP, while landscape fragmentation and human activities had mostly had negative effects. Furthermore, it was discovered that human activities contributed 80.05% of the total negative impact, specifically in the southern sandy lands and the Hetao Plain. Further, spatial analysis identified seven key driver zones with climate and landscape patterns contributing 56.09% to NPP growth. These findings highlight the value of landscape-based strategies for enhancing regional carbon sinks and offering both practical and theoretical guidance toward carbon neutrality.