Image Processing Reference
In-Depth Information
deemed by the Chicago School to be a manifestation of general biotic and cultural
forces (which lead to the term “urban ecology”), constrained by the particular physical
setting of the city.
Underpinning these physical structures and locational patterns is transportation.
Cities exist largely because transportation to accessible nodes in space provides the
rationale for the agglomeration economies that define them.
Sprawl for example is loosely associated with the tradeoff
between the desire to live as close to the city as possible
against the desire to purchase as much space as possible and
still retain the benefits of “urban” or “suburban” living.
Sprawl thus comes about through rising wealth and transpor-
tation technologies that allow such suburban development
and urban morphologies to reflect this tradeoff. The dynam-
ics of the processes defining such spatial interaction and land development are thus
central to an understanding of urban form and structure.
In both physical and socio-economic terms, the ways in which urban phenomena
are conceived very much determines the ways in which they are subsequently mea-
sured and then analyzed. Studies concerned principally with urban extent (such as
inventory analysis focusing upon the ways in which the countryside might be gobbled
up by urban growth) tend to be guided by definitions of the extent of irreversibly
urban artificial structures on the surface of the Earth. Such structures support a range
of residential, commercial, industrial, public open space and transport land uses.
Remote sensing classification of surface reflectance characteristics allows the
creation of simple, robust and directly comparable measures of
the dichotomy between natural and artificial land cover (read
relative discussions in Chapters 3-5). Of course, such urban
development is not necessarily entirely contiguous and, as
shown in Chapter 8, techniques of GIS can be used to devise
appropriate contiguity and spatial structure rules. In this
straightforward sense, it is possible to formulate fairly robust
and objective indicators of class and extent through the statisti-
cal classification of land cover characteristics and “spatial
patterning” of the size, shape and dimension of adjacent land
use parcels. These indicators can provide a useful and direct
measure of the physical form and morphology of urban land cover that is very useful
in delineating the extent of individual urban settlements and in generating magnitude
of size estimates for settlement systems (Batty and Longley
1994
).
Chapter 7 of this topic describes how developments in
urban remote sensing have led to the deployment of instru-
ments that are capable of identifying the reflectance character-
istics of urban land cover to sub-meter precision (also see
Donnay et al.
2001
; Mesev
2003
). In addition to direct uses,
remotely sensed measures are also of use in developing countries
where socioeconomic framework data such as censuses may
not be available. For reasons that lie beyond the scope of this
underpinning
the skeletal
structure of the
built form of
the city is
transportation
remote sensing
can provide a
useful and
direct indication
of the physical
form and
morphology of
urban land
cover in cities
remote sensing
represents a
complementary
data source to
traditional
socioeconomic
surveys
