The Coordinated Development and Evolutionary Characteristics of "Port-Industry-City" System in Fangchenggang City of Western China

Abstract Fangchenggang is a key port city in less developed western region of China, which is of typical characteristics and significant practical implications in its "Port-Industry-City" integrated development. The "Port-Industry-City" coordination model is utilized to evaluate the status and level of interactive development, employing dynamic development metrics and the scissors difference method to elucidate the evolutionary characteristics of integrated systems, thereby identifying the drivers and barriers to coordinated growth. Key findings reveal: (1) A consistent rise in the "Port-Industry-City" coordination index, with interaction levels progressing from moderate to high;(2) The complex systems have undergone different evolutionary stages, with "Industry-City" have an initial rise followed by a decline, "Port-City" and "Port-Industry" experiencing a cycle of synergy, low-level symbiosis, and back to synergy; (3) The year 2015 marked the lowest point of evolutionary speed in the "Port-Industry-City" system, with the city and port being lagging factors from 2011–2015, the port from 2016–2019, and subsequently the industry in 2019–2020; (4) The scissors difference shows an unstable "double W" pattern of alternating declines and rises, indicating fluctuating development patterns and highlighting the need for strategic actions in port expansion, refining the urban functional system, promoting the integration of port and urban industrial and value chains.