The Grassland Ecological Compensation Policy (GECP) is a large-scale project that has been investing in China since 2011. Despite the significant investment and long duration of the GECP, its impact on carbon sequestration in grasslands remains unclear. Based on panel data from prefecture-level cities in the Yellow River Basin (YRB) from 2000 to 2020, this study explored the effects of the GECP on grassland carbon sequestration in the YRB and its heterogeneity using a time-varying difference-in-differences (TV-DID) model. Subsequently, we predicted changes in carbon sequestration in grasslands under the influence of the GECP from 2021 to 2040 using a simulation. The main conclusions are as follows: First, the implementation of the GECP promoted carbon sequestration in grasslands. This conclusion was validated after conducting a series of robustness tests. Moreover, the effects of the GECP were heterogeneous across different geographical locations, highway densities, and grassland areas. Finally, the simulation results indicated that over the next 20 years, grassland carbon sequestration will generally increase but exhibit cyclical changes. The government should align the principles and objectives of the GECP with local geographic conditions, resource availability, and socio-economic development. It must formulate and implement tailored policies that maximize the ecological protection benefits of the GECP and promote carbon sequestration in the grasslands of the YRB.
Zhang et al. (Sun,) studied this question.