Evolution and Driving Factors of Regional Port and Shipping Service Corporations Network: A Case Study of the Yangtze River Delta Region

Port regionalization has led to inland expansion of the Port and Shipping Service Corporations (PSSCs), impacting regional development. Analyzing the evolution of Port and Shipping Service Corporations Network (PSSCN) is crucial for understanding changes in water transport capacity. This study on the Yangtze River Delta (YRD) region used PSSC data from 2012 to 2022, employing social network analysis and temporal exponential random graph models (TERGM). The results reveal that the YRD PSSCN has evolved from a low-level equilibrium to a collaborative polycentric structure, driving sustained improvement in network stability, clustering effects, and regional water transport efficiency. A hierarchical evolution is observed, with Shanghai as the primary hub, Ningbo as a secondary hub, and Nanjing and Suzhou as critical tertiary nodes. Hangzhou and Hefei facilitate linkages between inland and port cities, while some inland nodes exhibit weak linkages. Strong coastal localization exists, with the Shanghai-Ningbo corridor playing a key role. Corporate linkages between coastal ports and inland nodes mainly follow a Hefei-Shanghai-Hangzhou-Ningbo axis, while riverine-inland linkages center on Hefei, Nanjing, Suzhou, and Hangzhou. City size and geographical proximity are the most critical factors influencing the spatial propensity of PSSCs. Additionally, trade openness, telecommunication infrastructure, transportation infrastructure, organizational proximity, water transport connection, regional integration, innovation, and stability collectively shape the evolution of PSSCN. These findings reveal the evolutionary trends and determinants of regional PSSCN, highlighting the need to optimize the spatial allocation of infrastructure in future regional planning.