Mapping the evolution of impervious surfaces to investigate landscape metabolism: An Emergy-GIS monitoring application

This work investigates landscape metabolism (resource use change, ecosystem services, fragmentation) and urbanization processes over-time (1990-2006) in Campania Region and designs GIS based maps of impervious surfaces, in order to provide a way to assess the environmental worth and quality of lands. More than 5000 ha of newly urbanized areas appeared in the Campania Region during the investigated time period, mainly within the Provinces of Napoli and Caserta. A strict link emerges between expanding impervious surfaces and decreasing environmental quality, assessed through the emergy value of local resources. Emergy, a measure of the biosphere support to ecosystems and human-dominated systems, accounts for the value of natural capital lost or degraded, and consequently indicates the evolution of the investigated area towards a less sustainable state. The 7.76% (about 105,000 ha) of the regional area is presently covered by impervious surfaces, one third of which is concentrated in the Province of Napoli (about 38,000 ha). In order to reverse this trend, appropriate environmental planning and resource management are needed, specially focused to reducing the environmental problems associated with landscape overbuilding, natural capital loss and decreased availability of environmental services.