A retrospective analysis of the Barcelona Metropolitan System and its influence on the urban structure

Abstract

In recent decades due to the overflowing of the administrative boundaries by urbanization, the literature has studied various approaches to delimit the urban and metropolitan areas. Simultaneously, these urban dynamics have also led the metropolitan systems to polycentric structures characterized by dispersion and concentrated decentralization of employment and population, breaking with the paradigm of the monocentric city. However, few studies have focused on studying dynamically (over time) and jointly the delimitation of the metropolitan boundaries and its influence on the urban structure of the metropolitan areas. In this paper, the retrospective urban dynamics (1991-2001) and its influence on the urban structure of the Barcelona Metropolitan Region is analysed. Firstly, by analysing travel-to-work data, the functional metropolitan borders are delimited by the years: 1991, 1996 and 2001. Then, this paper studies how the growth of the metropolitan limits influence on the urban structure by characterizing their changes for the analysed period of time. In doing so, the urban structure is characterized by three key points: i) identification of urban subcentres by using a mobility approach (residence-to-work flows) at the time that it is estimated if they exert influence or not on the urban structure, ii) the complexity grade of the metropolitan system and, iii) the measurement of the polycentrism level taking into account its morphological and functional dimension as well as by proposing a new integrated approach. By having a dynamic perspective (1991-2001), results suggest a process of urban extension of the metropolitan borders what it could entail: an increment of sub-centres due mainly to the changes of the residential and labour markets, a more polynucleated structure of the urban system and a bigger grade of its complexity.