The impact of digital infrastructure development on the green transformation of cities: Considering the moderating effect of human capital level

To reveal the impact of digital infrastructure development (DI) on the urban green transformation (UGT) in the context of the digital economy. This is crucial for balancing economic development and environmental protection in the process of urbanization and digital development. Using panel data from 31 provinces in China from 2011-2021, this paper employs econometric methods and ArcGIS technology to explore in depth the relationship between the multiple impacts of digital infrastructure development on urban green transformation, while analyzing the moderating effect of human capital level in this process. The results show that: (1) DI significantly contributes to the UGT and this impact effect has a positive U-shaped nonlinear relationship. (2) DI has positive spatial spillover effects on UGT. (3) Positive moderating effect of human capital level (HCL) in DI for UGT. (4) There is a significant double-threshold effect of HCL, with a significant negative impact effect in the interval (0, 0.7446] and a positive moderating effect in the interval (0.7446, 4.1238]. As it continues to rise, the effect tends to saturate and the phenomenon of diminishing marginal benefit occurs.