The Impact of Digital–Real Economy Integration on Green Development Efficiency: Evidence from China’s Yangtze River Delta Urban Agglomeration

Enhancing green development efficiency (GDE) is of great significance in achieving regional green transition. Against the backdrop of rapid advancements in digital technology, digital–real economy integration (DRI) opens a new avenue for enhancing GDE. This research develops a theoretical analytical framework to analyze the influence of DRI on GDE. It employs panel data from 41 cities in China’s Yangtze River Delta urban agglomeration (YRDUA) spanning from 2011 to 2023 to develop a series of econometric models that empirically examine the impact of DRI on GDE and its underlying mechanisms. Research has demonstrated that the degree of DRI varies by region across the YRDUA, with a pattern of decreasing from east to west. Empirical results confirm that DRI development significantly boosts GDE in the YRDUA. Mechanism tests reveal that DRI indirectly enhances GDE through industrial structure optimization, green technological progress, and resource allocation efficiency. Moderation effects indicate that industrial collaborative agglomeration (ICA) significantly amplifies DRI’s positive impact on GDE. Further analysis indicates that the positive impact of DRI on GDE is only significant in low-carbon pilot cities and non-resource-based cities. Moreover, ICA exhibits a single-threshold effect: when regional ICA exceeds 2.0048, DRI’s impact on GDE demonstrates diminishing marginal returns. These findings not only give a realistic roadmap for accomplishing regional green transformation but also offer empirical evidence for policymakers to make scientific policies, adapt to local conditions, and appropriately promote ICA. This approach fully leverages the benefits of DRI, thereby advancing the economy toward sustainable development.