which has been overlaid at the previously vectorialized
classification. Then it was applied a clip between mesh and
classification of impervious areas, and for each square cell it
was computed the indices. It was also implemented a filter of
spatial correlation of 200m, through the use of a buffer. The
effectiveness of the filter consists in reaching a homogenization
of values, based on the generalized concept that nearby objects
tend to similarity. It also serves to avoid an unsuitable
fragmentation of data. Once obtained the final results of indices
for every impervious region in the cells, it was applied a cluster
analysis to automatically classify homogeneous areas,
consistently with those indicators and based on the conceptual
models of texture types previously theorized: continuous,
discontinuous, and scattered. Depending on these categories it
was merged all the polygons belonging to the same class, and
then exploded, to obtain the final database of polygons with
their own morphological characteristics (Figure 7). Further
analysis have been undertaken which aimed to quantify the
amount of every typology of urban texture, and the proportions
between them and the total amount of land consumption.
BH CONTINUOUS
EER DISCONTINUOUS
SCATTERED
Figure 7. Result of cluster analysis about urban texture types
4. CONCLUSIONS
For collecting the necessary data to provide analysis of urban
growth phenomena, the data which can be derived through
remote sensing is inherently suited to offer essential
information about the characteristics of different land cover
categories at different spatial and temporary scales. The
development of processing algorithms for satellite imagery and
techniques for getting information, accurately and consistently,
together with the development of analytical techniques and
methods for obtaining indicators of specific attributes for urban
growth modelling are essential tool to generate synthetic system
to cover all the main aspects, morphological, environmental and
socio-economical, about the dynamics of urban growth. The
relevance of this work is the possibility to analyze those areas
affected for high levels of land consumption, due to the
urbanization, and which kind of urban texture is being more
developed, it means, if the urban sprawl phenomena is leading
the urban policies, or if the cities are following a typical
Mediterranean model mostly based on the compactness.
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6. ACKNOWLEDGEMENTS
The authors of this paper acknowledge the research funding
provided by the Spanish Ministry of Education and Science
(SEJ2006-09630), the Spanish Ministry of Science and
Innovation (CSO2009-09057), the Spanish Ministry of
Development (E08/08), and the Spanish Ministry of Housing.
Acknowledgements are also due to the European Union through
the INTERREG IIIB Program (South Western Europe). For
technical support the authors strongly acknowledge Montserrat
Moix, Carlos Marmolejo, Jorge Cerda, staff members at Centre
of Land Policy and Valuations (CPSV) of the Technical
University of Catalonia (UPC) (Barcelona TECH).
