Abstract: Focusing on different ecological restoration models in the ecological transition zone on the eastern edge of the Qinghai-Tibet Plateau, we used the geographic detector and structural equation model to analyze the vegetation restoration effectiveness and reveal the multidimensional driving mechanisms of natural and socio-economic factors on vegetation restoration. The results showed that the effectiveness of vegetation restoration exhibited significant spatiotemporal heterogeneity from 2001 to 2019. Under the natural restoration model, the effectiveness of vegetation restoration gradually increased, while under the artificial restoration model, the effectiveness showed different trends in different time periods due to the influence of climate and human activities. The comprehensive restoration model performed significant differences between the central part of Gansu and the Gannan region, while vegetation generally showed a recovery trend. Temperature was the most important driving factor for vegetation recovery (q=0.36), while slope (q=0.09) had a minor effect. The driving mechanism was mainly characterized by nonlinear enhanced interaction, followed by double-factor enhancement. The promoting effect of socio-economic factors on vegetation restoration had continuously strengthened. In addition, the inhibitory effect of population pressure on the agricultural economy showed an overall decreasing trend, while the impact on the non-agricultural economy showed a phased characteristic of “first enhancement and then weakening”. The interaction between the agricultural economy and the non-agricultural economy shifted from mutual constraint during 2001-2015 to positive synergy during 2005-2019, indicating that the optimization of the industrial structure can significantly improve the efficiency of ecological restoration. This study deepens our understanding on the responses of fragile ecosystems to global change, providing practical references for the governance of fragile ecosystems and the optimization of ecological compensation mechanisms.

Key words: eastern Tibetan Plateau, net primary productivity, vegetation restoration, multidimensional driving mechanism