The role of ports in the dynamics of urban hierarchies

This study investigates the role of ports in the dynamics of the city size distribution in a system of cities based on their geospatial proximity. We used an interdisciplinary method based on the complex systems approach to explore the participation of ports in the urban hierarchy. We used the case of the Mexican urban system and its national port system, data from 1900 to 2010. We tested the assumption of universality in spatial systems applying an inferential data analysis classifying probability distribution functions associated with the city size measure. We identified cities associated with their closest port across the rank size distribution and mapped their spatial location. Findings suggested that top hierarchical cities have been associated with three port sites: Veracruz, Tuxpan, and Lazaro Cardenas. They have consolidated their importance even though the entrance of new ports in the urban system. However, these new ports have affected the large-scale behavior of the urban system. The dynamics of statistical distributions showed a trend from skewed to non-skewed distributions indicating that the system remains complex, but it has changed its large-scale behavior, from higher influence of large to medium city sizes.