Study region: The Xiliao River Basin in northern China, a semiarid region where large-scale vegetation restoration projects (e.g., the "Grain for Green" initiative) have been implemented since the early 21st century. Study focus: We established a modeling framework integrating the Biome-BGC model, geomorphology-based hydrological model (GBHM), and revised wind erosion equation (RWEQ) to (1) simulate ecohydrological processes over the past 40 years; (2) evaluate vegetation restoration effects on carbon sequestration, water resources, and sediment dynamics; and (3) identify synergies/tradeoffs among these elements under climate change and anthropogenic activities. This study systematically integrates three key ecological processes-carbon, water, and sediment-at the regional scale for the first time, providing a physics-based platform for evaluating the long-term comprehensive impacts of vegetation restoration measures on these processes. New hydrological insights for the region: (1) Vegetation recovery in the region has been positive, with more than 60 % of the area maintaining a balance between water consumption and supply. (2) Although vegetation restoration led to a significant increase in leaf area index (LAI) due to anthropogenic activities, it did not notably enhance carbon fixation through photosynthesis; however, it effectively reduced soil carbon loss by mitigating wind erosion. (3) The impacts of vegetation restoration on water and sand dynamics increased, where continued greening led to water depletion while reducing the risk of wind erosion. (4) Scale-dependent effects on the carbon-water relationship were observed, with short-term changes being more strongly influenced by meteorological variables. The results from this study not only aided in the understanding of the effects of the vegetation restoration on carbon, water and sand in semi-arid areas but also could be used to provide guidance for future ecosystem management and planning.