Geographical Types and Driving Mechanisms of Rural Population Aging–Weakening in the Yellow River Basin

Population aging–weakening has become a critical constraint on rural sustainability in China’s Yellow River Basin (YRB), posing substantial challenges to ecological conservation and high-quality development. This study develops a multidimensional evaluation framework categorizing rural aging–weakening into four typologies: general development type (GDT), shallow aging–weakening type (SAT), medium aging–weakening type (MAT), and deep aging–weakening type (DAT). Then, the XGBoost model is used to assess the factors influencing the spatial diversity of aging–weakening types in the rural population at different spatial and temporal scales. The key findings reveal the following: (1) The proportion of aging–weakening areas increased from 65% (2000) to 72% (2020), exhibiting distinct regional trajectories. Upper reaches demonstrate severe manifestations (34% combined MAT/DAT in 2020), contrasting with middle reaches dominated by GDT/SAT (>80%). Lower reaches show accelerated deterioration (MAT/DAT surged from 10% to 31%). (2) Spatial differentiation primarily arises from terrain-habitat conditions, industrial capacity, urbanization, and agricultural income. While most factors maintained stable directional effects, agricultural income transitioned from positive to negative correlation post-2010. Upper/middle reaches are predominantly influenced by geographical environment, with the role of socioeconomic factors gradually increasing. Lower reaches exhibit stronger economic–environmental interactions. (3) This research provides actionable insights for differentiated regional strategies: upper reaches require ecological migration programs, middle areas need industrial transition support, while lower regions demand coordinated economic–environmental governance. Our typological framework offers methodological advancements for assessing demographic challenges in vulnerable watersheds, with implications extending to similar developing regions globally.