Systematic Coupling and Driving Factors Between Urban Land Use Efficiency and Ecological Carrying Capacity: A Case Study of Shandong Province, Northern China

Because of the adverse ecological impact of rapid urbanization, coupling the study of urban land use efficiency (ULUE) and ecological carrying capacity (ECC) is vital for harmonizing socioeconomic growth and environmental protection, and promoting regional sustainability. This research focuses on 16 cities in Shandong Province, utilizing SE-DEA, DPSIR models, and entropy-TOPSIS to study the interaction mechanisms of ULUE and ECC by coupling coordination analysis employing models, relative development indices, and geographic detector. During 2000–2020, the results show that ULUE first increased from 1.11 to 1.15 and then declined to 1.07, exhibiting an overall decreasing trend. ECC nearly doubled, rising from 0.25 to 0.59. The coupling coordination degree between ULUE and ECC improved from intermediate coordination (0.72) to good coordination (0.89). By 2020, the system reached a state of coupling coordination, although ECC development lagged behind (K = 0.58 < 0.8). Key driving factors for ULUE, ECC, and their coupling coordination were capital investment scale, resource and environment regulation, and capital investment scale, respectively. This reveals the changes in the interaction mechanism of ULUE and ECC in the three stages, indicating that ULUE and ECC will gradually form imbalance to coordinated development driving by these factors in different stages of urban development.