SOC erosion reduction of the “Grain for green” program on the Loess Plateau, China

Soil erosion is a primary driver of terrestrial carbon loss, particularly in the Loess Plateau of China, where intense erosion processes mobilize substantial quantities of soil organic carbon (SOC). While vegetation restoration is widely acknowledged as an effective approach to mitigate erosion and enhance SOC sequestration, its effectiveness in reducing SOC loss at the regional scale remains insufficiently quantified. This study synthesized the dataset from 183 sites comprising 1950 observations across the Loess Plateau to assess the effects of land-use changes on soil erosion and SOC loss. Additionally, key environmental factors including slope, slope length, precipitation, vegetation cover, and soil properties were analyzed to determine their relative impacts. Compared to cropland, areas undergoing vegetation restoration exhibited significantly reduced soil erosion and increased soil organic carbon content. The implementation of the “Grain for Green” Program (GGP), covering 5.6 × 10⁶ ha of the Loess Plateau, resulted in an estimated annual reduction of approximately 1.7 Tg C of SOC erosion, accounting for about 11 % of the ecosystem carbon sequestration under the GGP of the Loess Plateau. These findings underscore the importance of tailoring restoration strategies to specific topographic and climatic conditions to maximize the dual benefits of soil conservation and carbon sequestration. The insights gained from this study provide a scientific basis for precision ecological management and policy development in the Loess Plateau and other similarly degraded regions.