The identification of spatial patterns in city limits through self-organized maps of the centrality of the road network

Abstract

The characterization of city limits is of especial interest since it may provide hints to understanding the urban growth taking place in peripheries, and it also makes it possible to identify the keys to the continuous and discontinuous relationships between cities and their surroundings. Within this context, many different approaches could be adopted to undertake this kind of analysis. This paper specifically explores the possibilities offered by the use of self-organized maps created from the results of the application of different centrality measures in the mixed road network, which is comprised of systems of streets, metropolitan roads and rural roads. The implementation of centrality measures to a mixed road network is already an innovative exercise, considering that centrality analyses are normally carried out in more purely intra-urban contexts. The spatial representation of the profiles obtained with the self-organized maps shows different structural characteristics throughout city limits, which can be used to interpret the nature of the boundary itself. The proposed methodology was tested in the city of Granada (Spain), specifically on the limit in contact with the area surrounding the Vega de Granada, a singular agricultural landscape linked to the Genil River.