Spatio-temporal differentiation and influencing factors of coupling coordination degree in the economy-ecology-green finance system across nine provinces (regions) of the Yellow River Basin

The Yellow River Basin, a vital ecological barrier and economic core in China, fulfills dual functions of ecological security and regional economic development. Under “Dual Carbon” goals, coordinating green finance for economy-ecology system development is critical. This study innovatively incorporates green finance into the research framework of economy–ecology coordinated development in the Yellow River Basin. Taking the nine provinces (regions) of the Yellow River Basin as the research object, this study first employs the AHP-entropy weight method and the TOPSIS model to comprehensively evaluate the development levels of the three subsystems. Subsequently, the coupling coordination degree (CCD) model and spatial autocorrelation analysis are applied to reveal the coordinated evolution patterns and spatial agglomeration characteristics of the three systems. Finally, the Dagum Gini coefficient and the Geographically and Temporally Weighted Regression (GTWR) model are adopted to further identify the sources of regional disparities and spatiotemporal heterogeneity characteristics. Key findings include: 1) The coupling coordination degree shows an upward trend across nine provinces (regions), with provincial evolution differentiating into four patterns and demonstrating a spatial distribution of “lower reaches > upper reaches > middle reaches”; 2) Moran's I index increased from 0.236 to 0.407, indicating enhanced spatial agglomeration effects and intensified high-high clustering correlation; 3) Inter-regional disparities exhibit an upward trend, with inter-regional differences constituting primary sources of overall disparity; 4) Significant spatial-temporal heterogeneity exists in driving factors of the economy-ecology-green finance coupling coordination, where per capita GDP, energy consumption per capita, and domestic waste treatment rate emerge as core determinants. This research provides theoretical foundations and practical references for optimizing collaborative governance mechanisms and green financial resource allocation in the Yellow River Basin. • Analyzed coupling coordination degree (CCD) of economy, ecology and green finance. • Significant spatial clustering of CCD was observed. • Interregional differences had a greater impact on CCD than intraregional ones. • The influencing factors of CCD exhibited spatiotemporal heterogeneity.