Synergistic gains in vegetation carbon density and green industry output: Evidence from Sand-Fixation Ecological...

Desertification threatens global dryland ecosystems, yet current efforts often prioritize short-term greening over local livelihoods. As an adaptive policy initiative, China implemented Sand-Fixation Ecological Function Zones (SFEFZ), but its long-term effectiveness in enhancing ecological and economic resilience remains unquantified. This study employs a matched comparison to evaluate the SFEFZ policy between 2005 and 2020, covering 71 policy counties and 33 matched controls in northern China. By integrating vegetation carbon density (VCD) from GEDI-MODIS fusion with county-level green industry output value (GIV), we assess the policy's ecological and socioeconomic impacts. Results show that adaptive adjustments within SFEFZ played a key role in strengthening carbon sinks and promoting green industries. The expansion of desertified land in SFEFZ areas (0.41%) was lower than in non-SFEFZ areas (5%), and the VCD increase was 2.4 times higher. Meanwhile, GIV annual growth in SFEFZ areas (8%) exceeded that of non-SFEFZ areas (5%). Crucially, dynamic phase-wise analysis and DID estimates reveal a causal transition where VCD temporarily declined and GIV grew after the first adjustment, then VCD reversed to positive gain and GIV accelerated after the second. These findings indicate that phased policy adjustments helped break the vicious cycle between desertification and underdevelopment. This study highlights that phased and integrated policy adjustments can generate synergistic benefits between ecological restoration and economic development. It provides a replicable method for land restoration policies and offers empirical support for advancing resilient dryland governance in alignment with the Sustainable Development Goals.