Research on the evolution and driving characteristics of cultural-tourism integration efficiency in urban clusters of the Yangtze River Delta

The integration of culture-tourism is an important strategy for achieving economic circulation and sustainable development in global urban agglomerations. Utilizing the Epsilon-Based Measure (EBM) model, Malmquist index, and spatial analysis, this study investigated the efficiency across 27 central cities in the Yangtze River Delta (YRD) from 2015 to 2019. The results were as follows: (1) Significant spatial heterogeneity existed; certain developed cities initially exhibited input redundancies in tourism infrastructure and cultural facilities, yet overall efficiency reached high levels by the end of the study period. (2) Returns to scale showed multidimensional differentiation, manifesting as continuous growth, decline, and fluctuation, indicating unstable development paths. (3) Dynamic efficiency improvements were primarily driven by technological progress, with most cities approaching the production frontier over time. (4) High-efficiency clusters were concentrated along coastal and riverine corridors, though regional collaborative effects remained underdeveloped. Three distinct development models emerged: a resource-driven model that relies on distinctive local endowments to achieve high efficiency, a technology-led model that leverages balanced innovation and management, and a transitional optimization model that enhances efficiency by reducing redundancies. These results demonstrated that achieving high-quality integration requires both resource allocation optimization and technological empowerment. The findings provided a scientific basis for promoting deep integration of cultural-tourism in the YRD urban agglomeration and for the coordinated development of cultural-tourism in other urban agglomerations worldwide.