A territorial embeddedness analysis based on transport flows: Classifying the intra-urban space of the Rio de Janeiro metropolitan area

Abstract

The way we think about cities is conditioned by the way they have been historically structured: a central business district (CBD) surrounded by suburban housing. Nevertheless, deep urban transformations took place in many cities from the mid-twentieth century onwards, including activity decentralisation and a growing detachment between form and function. Hence, while there still are substantial travel dynamics between core and periphery, socio-spatial interaction patterns within large cities complexify and become more explicit. That is, localities outside the CBD develop ties such as cooperation, complementarity, and mutual influence. Proper identification of those interaction patterns is paramount to identify emergent subcentres and latent synergies that might be fomented, thus aiding better-targeted transport policies. In that context, we proposed a territorial embeddedness analysis (TEA), which consists of two steps implemented in the Rio de Janeiro Metropolitan Area (RJMA). Firstly, we applied graph theory to flow data from the 2013 Household Travel Survey (HTS) to detect the main centralities, which then serve as the basis for calculating the TEA relational indices. Secondly, the k-means algorithm was applied to these indices to organise the HTS traffic zones into seven groups. Our findings allow us to place localities into two opposing categories. The first is that of places that need longer trips to access resources, while in the second category, there are places most associated with shorter trips. Three further situations can be distinguished within this second category: (a) areas near first-order centralities; (b) classical peripheries that access resources either in closer subcentres or on scattered areas nearby; and (c) highly segregated places that are unable to properly access the city’s resources. Overall, we believe this classification allows planners to better understand the complex relations taking place in metropolitan areas, which have evolved far beyond the core-periphery model. It can also foster the implementation of place-specific policies, such as restructuring the transit network based on local specificities and regional goals.