Soil occupation efficiency and landscape conservation in four Mediterranean urban regions

This study investigates the relationship between soil sealing and landscape conservation in four Mediterranean regions (Athens, Barcelona, Lisbon, Rome) characterized by different patterns of urban expansion. Per-capita sealed land, a landscape conservation index and selected territorial variables were considered into a multivariate exploratory framework aimed at assessing the correlation between land-use efficiency (based on the degree of soil sealing per-capita) and the quality of suburban landscape. A population density gradient with intensity of sealed land decreasing with the distance from the central city was observed in compact urban regions such as Athens and Barcelona. A mixed urban gradient was observed in Rome and Lisbon. In all the considered cities the spatial distribution of per-capita sealed land was not correlated with the urban gradient indicating that land consumption follows place-specific patterns irrespective of landscape quality. These findings suggest that urban containment and landscape conservation are policy targets requiring environmental measures irrespective of the prevailing morphology of the urban region (compact vs dispersed). In this context, green infrastructure planning is a promising tool for landscape conservation and the containment of soil sealing within fragile and dynamic contexts such as the wildland-urban interface.