Dynamic measurements and mechanisms of coastal port–city relationships based on the DCI model: Empirical evidence from China

Abstract

The port–city relationship is not only one of the major contradictions in the development of port cities but also an important factor that affects the sustainable development of coastal areas. Therefore, determining the port–city relationship and identifying the mode of port–city interaction are difficult yet popular topics in research on port cities. The argument is based on a reciprocal port–city relationship. This study uses the main coastal port cities in China as research objects to propose the dynamic centralisation index (DCI) of port–city relationship based on the relative concentration index and to verify its effectiveness. In accordance with the measurement and classification of port–city relationships between 2001 and 2015, we discuss the influences of port sizes and internal structural changes on the port–city relationship. In addition, we use the impulse response function to explore the mechanisms of different types of port–city relationships. The primary objectives of this study are as follows: (1) to propose a new measurement model of port–city relationship that fully reflects the relationships of port sizes and structural changes to urban development; (2) to use the DCI model to classify port–city relationships, explore the change characteristics of different types of port–city relationships and further verify the validity, sensitivity and applicability scope of the DCI model and (3) to determine the manifestation of port–city interaction and identify its dominant factors in different port cities. The strength or tendency of port–city relationships is not directly related to port or city size but is closely associated with underlying issues, such as the development stage of port or city and the relationship between port and hinterland.