Polycentric urban system, accessibility, and demographic “gradients” in Extremadura (Spain)

Abstract

In recent decades, strong territorial imbalances have accelerated, largely as a result of the process of economic and demographic concentration in cities on a planetary scale. Faced with this situation, the main European institutions and even the UN propose a polycentric model of cities that should decentralize development and stabilize the rural population. In this sense, Extremadura is a paradigmatic case in Spain: it is a rural, inland and border region, but it still maintains half of its population in rural areas and has no abandoned municipalities. This is due to a more concentrated population and its polycentric system of cities, which to a large extent explain it. However, it has a wide outer fringe with significant depopulation. In order to improve access to this outer fringe, a GIS network analysis has been carried out and a series of accessibility ranges have been established, which have made us to find regressive and regular “gradients” in all demographic variables up to 40 minutes. Beyond this distance, population losses are close to 65 %. In addition, the extension of the polycentric system is proposed with the promotion of five nuclei, traditional regional headwaters in these peripheral areas, with which 85.6 % of the population would be less than 30 minutes away from this urban system and 98 % less than 45 minutes away.