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Stefan Fina Patterns of Urban Sprawl Geographical Analysis
The summarized shortcomings of the proposed indicators are:
- They fail to perform when they are applied to areas with differing levels of urbanization, where
some urban patches may be considered self-sufficient to some degree and others are dependent
entities (“scalability”).
- They do not give effect to the geographic setting in a study area, but rather operate “in the void”,
i.e. there is no consideration for development constraints and many ignore the internal setup of a
city. The problem is all too often reduced to an analysis of built-up versus non-built up
configurations of urban footprints.
- Moreover, there is no consideration for the preexisting settlement structure as a baseline for
assessment. Due to economies of scale, efficiency gains are likely if settlements amalgamate and
densities increase. It is often difficult to say where undesirable dispersion turns into a desirable
concentration of urban functions, and vice versa if urban areas are in a state of deconcentration.
In conclusion, the conceptual ideas for these indicators have to be rethought. The challenge is to
capture the state of urban sprawl in a real world where historically grown cities mature to polycentric
city structures or larger metropolitan areas that are functionally interconnected, and both growth and
shrinkage of urban regions can be assessed.
Measuring dispersion
In this context, the rethinking of dispersion as a key variable in urban sprawl monitoring is based upon
the work of Galster, Hanson, Wolman and Coleman (2001). Their study demonstrates from a
conceptual point of view that it is mainly the distance and intensity of interactions between agents of
energy consumption (households, businesses) that lead researchers to believe that a compact
geographic composition is preferable from a policy point of view. Highly dispersed urban functions
cause higher costs in terms of infrastructure provision and travel distances, but the first fundamental
question is: How do we represent these functions in a measurement concept? Most research on urban
sprawl operates with generalized representations of these agents of energy consumption and makes
assumptions around their energy use and the levels of activity of and between their spatial locations
(for example households, buildings, land use zones, or even urban footprints as a whole). Torrens and