Abstract
In this study, we investigated the spatio-temporal synergistic relationship between ecological urbanization (EU) and industrial eco-efficiency (IEE) in the context of the integrated development of the Yangtze River Delta region. The main findings are as follows: (1) EU and IEE generally exhibited similar spatial distribution patterns, with high values concentrated in the southern part of the delta and low values in the northern part and Anhui Province; there was also a high degree of coupling between the two systems. (2) IEE and EU's relationship presented a U-shaped positive correlation trend from 2001 to 2019, and a positive correlation was observed in most cities, with highly correlated cities clustered in southern Zhejiang and Anhui province, while negative correlation cities scattered in a few cities in northern Zhejiang, northern Anhui, and southern Jiangsu. (3) Significantly spatial association characteristics were found between EU and IEE, with HEUHIEE type clustering mainly in southeastern delta cities, while the LEULIEE type slowly encroached upon northwest delta cities. (4). Synergistic promoting effects were identified between IEE and EU, whereby, the improvement of IEE in both local and neighboring cities contributed to promoting EU, and the progress of EU in both local and neighboring cities helped to promote IEE.