Water Budgets Control the Resilience of Large-Scale Ecological Restoration

Abstract

Large-scale ecological restoration is a key nature-based solution to environmental challenges. However, the resilience of such initiatives is debated due to increasing water consumption. This study examined China's Three-North Shelterbelt Forest Program, the world's largest ecological restoration project, to assess how water regulated vegetation resilience from 2001 to 2022 and projected future vegetation suitability by integrating meteorological observations, remote sensing data, and Global Circulation Models. We found that approximately 48.2% of vegetation, particularly forests, experienced declining resilience despite greening. Resilience increased with productivity within water resources carrying capacity but decreased when exceeded. Forest resilience peaked when precipitation was fully utilized, whereas grassland resilience was lowest at this equilibrium. By 2050, 1.8% of the area is projected to face degradation risks, with an additional 11.1% at potential risk under the SSP2-4.5 scenario. Overall, our findings highlight the necessity of integrating water resources constraints into ecological restoration strategies for sustained effectiveness.