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Stefan Fina Patterns of Urban Sprawl Geographical Analysis
relation possibly varies between different types of urban areas and also transport opportunities
(pedestrian, public transport, road network).
- The inputs into calculations are critical. The nearest neighbor method may be suitable to detect
closest facilities, but there is no information about the quality or attractiveness of these facilities.
On the one hand, additional information on business locations and public services (i.e. number of
workplaces, attractiveness index, etc.) would help to assess the importance of connections more
precisely. On the other, it would also add complexity since it would require rankings of likely
origin-destination combinations.
- The focus is currently on residential urban entities. It is possible that new industrial sites are
developed further away from the existing residential area and that the FT does not react since new
closest connections are not being established.
Synthesis
The impacts of dispersed urban entities on the resource efficiency of urban systems present a number
of challenges for quantitative research. Meaningful indicators need to give effect to functional aspects
in order to add value to urban sprawl assessments. Two new measurement methods were introduced
and tested that address these requirements, adapting nearest neighbor algorithms to specific urban land
use change questions. The Dispersion Index models the limits of growth in an area, described as the
theoretical maximum sprawl of urban entities. With the actual distribution being compared to the
maximum sprawl, the measure can support longitudinal monitoring as well as comparative analysis
and inform decision-makers about the current situation and evaluate development paths. An important
addition to the concept of this indicator is the inclusion of development constraints and the
differentiation of the resulting nearest neighbor ratios for different levels of urbanization. Test cases
show that the indicator would be useful in assessments of greenfield vs. infill development. The
second indicator, the Functional Triangle (FT), focuses more specifically on the accessibility and land
use mix of urban functions. It measures the distance between residential entities with the nearest
businesses and public services and averages all connections in an area to a mean FT distance. From a