The spatial impact of urban compaction: A fine-scale investigation based on Merseyside

In England, urban compaction has been adopted as a policy to prevent further sprawl, and thus reduce the environmental footprint of urban areas However, currently there is only limited information available on the environmental impacts of urban compaction within built-up areas. In this context, the study explored landscape changes in residential areas in Merseyside over a period of 25 years. Eleven sample areas were selected, representing a range of socio-economic situations from affluent to deprived areas. A method based on a geographical information system was used to estimate land use and cover change on a fine scale from aerial photographs taken in 1975 and 2000. Land use and land cover have been shown to be related to the environmental performance of urban areas. In all 11 study areas, the amount of built and paved surfaces significantly increased over the study period while green space was lost. The types of green space lost and the reasons for this loss differed between areas and were related to their socio-economic status as measured by an index of multiple deprivation. As a consequence of these land use and land cover changes, negative environmental impacts were predicted for all sample areas. It is concluded that more weight needs to be given to the protection and management of urban green spaces. Only then can compact cities truly become sustainable.