Soil Sealing in the Growing City: A Survey in Rome, Italy

This paper illustrates a procedure aimed at estimating diachronically soil sealing in suburban areas by using cartographical and statistical data. The procedure was applied (1949-2006) to the metropolitan area of Rome (Italy), a Mediterranean city with important land use changes observed during the last fifty years. A total of 1.477 random sites was chosen encompassing the entire investigated area (1.285 km2) and evaluated in terms of sealing condition in 1949, 1990, 1994, 2000, and 2006. Although resident population has been found quite stable since 1970s, the sealed surface area grew rapidly from 8% in 1949 to 26% in 2006. The sealing status of each site was found correlated to the distance from the city centre, while not correlated to the distance from the major roads, railways, and the boundaries of the neighbor protected area. These results suggest that soil sealing in Rome was associated to recent processes of urban sprawl which testify the slow transition from the semi-compact city to a more diffused urban agglomeration.