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Stefan Fina Patterns of Urban Sprawl Geographical Analysis
Introduction
In the past decades, land conversions to urban uses and their associated impacts on the environment,
but also on economical functions and society at large, have led many governments to formulate
political strategies to control urban growth. Conservation strategies today are complemented by
planning instruments to stop excessive urban growth and reduce land consumption rates. At the same
time, the functional configuration of land uses within and between city environments has become a
main topic of concern. Growth strategies have been proposed and implemented that promise to use
infrastructure more efficiently and have a lower impact on ecological systems. Within the research
community there is wide agreement that compact and planned developments with a high mix of land
use functions and good integration within the existing urban compound are preferable over low-
density, isolated developments that are so typical for urban sprawl (Dielemann and Wegener 2004;
Glaeser and Kahn 2003; Cervero 2001; Real Estate Research Corporation 1974). At the same time,
awareness about the role that urban structures play for the long-term sustainability of cities and their
resource consumption does not necessarily stipulate appropriate decision-making. Many planning
regimes struggle with the task to comprehensively assess the impacts of new developments, especially
in the light of persisting development pressures and a poor understanding of the cumulative effects
that many single developments sum up to in terms of landscape fragmentation and resource efficiency.
On this background, this paper reflects upon quantitative tools to describe the state and trends of urban
sprawl. It explains why current monitoring systems for urban sprawl have difficulties to assess urban
land use configurations in this context: There is no reference for urban sprawl assessment that would
work for all study areas, and the geography of a place needs to be considered. Another shortcoming is
that existing approaches very often work with representations of urban land that ignore their internal
make-up and function. On this background, two new indicators based on nearest neighbor analysis are
introduced that address these issues. Their properties are described in simulated test cases and a study
area in southern Germany. A discussion about indicator performance and prospects for future research
conclude the article.