Urban fragmentation map of the Chamberí district in Madrid

High levels of mobility have given rise to land-use patterns that are difficult to navigate for non-motorised transport users. Fragmentation in a transport system can be considered as a lack of connectivity (or permeability), as infrastructures reduce the connectivity between places. Fragmentation has been extensively studied in landscape ecology, and can be understood as a loss of connectivity. Connectivity is defined as the degree of permissiveness offered by the landscape for the displacement of organisms, energy flows and dispersive movements. This article presents a map of urban fragmentation for pedestrians using a habitat fragmentation indicator. It represents difficulty for pedestrian mobility as a function the of the accumulative cost distance over a cost surface under the current motor traffic-oriented street/mobility layout. The map is developed for the Chamberí district in Madrid (Spain). The process consists of first developing the resistance matrix of the territory database. The resistance value is the time taken to travel through the streets. The street axis network is converted into pavements, as this is the part of the street used by pedestrians, including pedestrian crossings and traffic lights. The resistance value -travel time - is calculated, including waiting time. Once the resistance matrix has been created, GIS functions are used to calculate the least accumulative cost distance for each origin to a set of attractive locations/destinations for pedestrians.