Urban ecological resilience and industrial structure optimization coupling coordination in the Beibu Gulf Urban Agglomeration

The synergy of industrial transformation and ecological security is an important pair in the regional high-quality development. Previous studies of the Beibu Gulf Urban Agglomeration have mainly examined industrial development, ecological carrying capacity, low-carbon transition, or environmental resilience separately, leaving the coordinated evolution of industrial structure optimization and urban ecological resilience insufficiently understood. This gap is particularly relevant for late-developing coastal urban agglomerations, where rapid industrial restructuring occurs alongside increasing ecological pressures. To address this issue, taking the Beibu Gulf Urban Agglomeration as the study area, an evaluation system for industrial structure optimization and urban ecological resilience was constructed, and the coupling coordination between the two systems was examined from 2012 to 2022. The contribution of this study lies in integrating industrial structure optimization (ISO) and urban ecological resilience (UER) within a unified analytical framework and simultaneously examining their temporal evolution, spatial differentiation, subsystem-lagging characteristics, and interacting driving factors. The findings extend the empirical understanding of industrial–ecological coordination in late-developing coastal urban agglomerations and provide a quantitative basis for differentiated sustainability governance. Results indicate that the industrial structure optimization and the urban ecological resilience had steadily improved over the study period, however, there remained large inter-city variation. The average coupling coordination degree rose from 0.338 in 2012 to 0.432 in 2022, which reflects the changing trend of mild disorder-to-near-order but overall systems still not into the coordinated development stages. At the spatial level, the coordination pattern was featured with a remarkable core, higher values in northern regions and differentiated performance among coastal port cities. Nanning booth performed as a leader city and FangchengGang better Chongzuo always weak. The results of the geographical detector show that development of digital economyhas a dominant explanatory power on gross regional environmental quality, followed by science–technology input, economic development, transport accessibility and environmental regulation. The results of interaction detection indicate that the synergistic effect of digital economy and science-technology input has the strongest explanatory power. These findings identify the major factors and interaction patterns associated with spatial differences in industrial–ecological coordination and provide quantitative evidence for differentiated governance in late-developing coastal urban agglomerations.