Urban Sprawl and the Quantification of Spatial Dispersion

Abstract

The uncontrolled spread of cities into their surrounding rural and natural land is an issue of high popular interest and has been the topic of considerable research. Urban sprawl remains controversial, even though among scholars there are still no unambiguous definitions of sprawled zones--their spatial form and their causative factors--nor about the urban processes and dynamics involved. In order to create such a definition, the authors describe the spatio-temporal patterns of urban form in a study area noted for sprawl, focusing on measures that can detect the degree of urban spatial dispersion over time (Batty 2002). The data used is a fusion of archived thematic maps, classified satellite imagery, census data, and forecast maps of future urban scenarios. The area investigated was the northeastern province of Pordenone in Italy, which is particularly relevant and curious because despite being a small city, it was assessed in 2002 as one of the most explicative examples of sprawl in Europe by the European Environment Agency. The authors analyzed urban growth mainly through the evolution of urban patterns over time, hence sprawl is considered as a specific case of growth that drives urban expansion from denser and compact extent to an unorganized and fragmented pattern. How the spatio-temporal dynamics of urban growth are quantified is crucial for urban planners, as knowledge of amounts and rates allows more efficient selection and application of policy and could help researchers to better understand urban sprawl’s etiology.