Definition of spatio-temporal levels of accessibility. Isochronous analysis of regional transport networks

Accessibility to transport networks affects the ability of citizens to carry out necessary activities in their daily lives. In particular, in small and medium-sized centres where only some essential services retain a proximity attribute, we are seeing an increasing number of daily travels, the distances travelled and the time taken by local citizens for primary (work, health, education, etc.) and secondary (leisure, etc.) mobility needs. In polycentric and widespread territorial contexts, such as those typically Italian, accessibility is therefore synonymous with spatial equity. In this disciplinary debate, the present research aims to analyse analytically the levels of accessibility of individual administrative units to the main transport networks. To this end, a semi-automated method in GIS environment for the definition of municipal levels of space-time accessibility is proposed based on an isochronic analysis conducted on access nodes to major transport, motorway and rail networks, at the territorial scale. The paper also presents the results obtained from the method application in the Calabrian regional context useful to support the adoption of a planning approach oriented towards territorial integration between mobility needs and the programming of the network of services that typically characterizes the urban planning discipline.