by M Dallimer, Z Tang, PR Bibby, P Brindley, KJ Gaston, ZG Davies
Biology Letters 7:763-7662011
As the population of cities grows around the world, growth can be addressed by increasing density within cities or by allowing development to “sprawl” beyond the existing limits. Increasing density comes with the risk of reducing urban greenspace, and thus the benefits it brings to humans, the opportunities for biodiversity conservation, and the provision of ecosystem services. To study the temporal changes in the amount of urban greenspace in the 13 largest cities in England, Landsat Thematic Mapper data from 1991, 2001, and 2006 was used, supplemented with spectroradiometer Enhanced Vegetation Index data (2000-2008) to allow for the detection of changes at smaller scales. An overall increase in greenspace from 1991 to 2006 was found despite a substantial increase in the number of dwellings. A closer examination, however, showed an increase up to 2001 followed by a decrease thereafter, corresponding to a change in national policy in 2000 that encouraged the development of brownfields and higher density of housing units per hectare.