How Do Ecological Restoration Programs Shape Grain Production? Evidence From China's Three‐North Shelter Forest Program

ABSTRACT Balancing ecological restoration and grain production is a core challenge for land management in arid and semi‐arid regions. Large‐scale ecological engineering programs are often assumed to constrain agricultural output through land‐use competition, yet rigorous causal evidence on their long‐term effects and underlying mechanisms remains scarce. This study investigates whether and how China's Three‐North Shelter Forest Program (TNSFP) affects grain production. Guided by the social–ecological systems framework and ecosystem services theory, we hypothesize that large‐scale ecological restoration can enhance agricultural output through improvements in ecosystem services rather than crowding out cropland. Using county‐level panel data from China covering 2000–2022, we estimate the causal impact of TNSFP on grain production employing a difference‐in‐differences (DID) model, parallel trend test, placebo test, and multiple robustness checks. Grain production data are combined with satellite‐derived vegetation indices, air quality indicators, and ecosystem quality measures to identify mechanism pathways. The results show that, first, the TNSFP significantly increases county‐level grain production, and this positive effect remains robust after controlling for agricultural inputs, climatic factors, and socioeconomic conditions. The parallel trend test is passed, and the findings are further supported by placebo tests and multiple robustness checks. Second, mechanism analysis demonstrates that improved vegetation cover, enhanced air quality, and overall ecosystem quality jointly promote grain production, thereby supporting the proposed ecological pathways. Third, significant regional heterogeneity and moderating effects are observed: the policy effect is stronger in Northeast and North China, and is positively moderated by cropland area but negatively moderated by the relief degree of land surface. These findings provide new causal evidence that ecological restoration can generate synergistic benefits for land restoration and food production, offering important implications for sustainable land management in dryland regions.