Abstract:    Green innovative development is one of the core issues of Chinese modernization, and promoting locally-differentiated innovation and regionally-coordinated development is a critical engine and key decision for this process. This paper constructed the SBM-DEA model to measure the green innovation development level of Beijing-Tianjin-Hebei and surrounding areas from 2005 to 2019. It explored the spatial distribution and evolutionary characteristics using the spatial autocorrelation, standard deviation ellipse and Kernel density methods, and revealed differences and their sources with the Dagum Gini coefficient. The paper also tested for convergence using the coefficient of variation and econometric models. The findings are as follows: Overall, the green innovative development in Beijing-Tianjin-Hebei and surrounding areas exhibits a U-shaped spatial linkage trend characterized by low intensity, instability and imbalance, with four types of agglomeration patterns coexisting. The standard deviation ellipse extends along the southwest-northeast direction, with high fluctuation frequency in the rotation angle and the center located in Hebei, reflecting an alternating pattern of agglomeration and expansion. The global Kernel density curve shows rightward shifts of varying degrees, predominantly unimodal, with gradually decreasing peak values, increasing bandwidth, and a pronounced rightward tail. The local Kernel density curves show the diversified and asymmetric features such as twin peak, right-tail, alternating movement, with a high degree of dispersion. The Gini coefficient initially decreases and then increases, indicating an obvious convergence-divergence trend, with regional differences and density of transvariation being the main sources. There is no σ-convergence, but absolute and conditional β-convergence characteristics are present. Therefore, it is necessary to implement such measures as balancing target differentiation, coordinating development pace, aligning specialized divisions of labor, and improving performance systems.

Key words: green innovation development, spatial distribution, dynamic evolution, Beijing-Tianjin-Hebei and surrounding areas