Image Processing Reference
In-Depth Information
It is not a coincidence that the urban transition has occurred in concert with the
worldwide increase in population over the past 200 years. The urban transition is
an inextricable part of the demographic transition because they both have roots in
the same sets of technological advances that have rocked the world. The root cause
of modern population growth is the massive drop in death rates that has been
brought about by scientific control of disease, and by the
provision of more and better food, shelter, and clothing.
These are part and parcel of the industrial changes occa-
sioned by technological advance. Modern technology
allowed an increase in agricultural output per worker,
which permitted more people to be freed from agricultural
activity and were thus available to move to jobs being
created in cities. Technology also helped improve the
health of the population, which led eventually to cities
being demographically self-sustaining (i.e., having a posi-
tive rate of natural increase and thus not being completely dependent upon migra-
tion for population increase). At the same time, technology was expanding the
possibilities for city size and structure because premodern technology did not
permit buildings to be very high or very deep - they were physically restricted to
being close to the surface which clearly limits the potential population density and
thus city size because: (1) cities had to be compact enough to be traversed easily on
foot; (2) roads did not have to be very wide or regular in shape because they did not
have to accommodate fast-moving motorized traffic; (3) population size was limited
by the ability to supply the city with water and with some way of getting rid of
human waste; (4) population size was limited by the ability to supply the city with
food, which in the absence of refrigeration limited locations of cities to those places
near a ready agricultural supply; and (5) economic activity was labor-intensive and so
there were no special spatial advantages to having manufacturing done in the city;
rather it could be “farmed” out to people living outside the city, meaning that cities
were largely service (including government and finance) and commercial centers,
which limited the variability in land use.
Technology has led to a larger population worldwide through its impact on
controlling mortality, but has also led to the need for that population to be increas-
ingly urban - to get out of the way of the mechanization of agriculture which is
required to feed the larger population. Thus, only in modern
times has it been not only possible but also necessary
for any but a small fraction of the population to live in
cities. Technology has led to the ability of food to be
preserved and shipped farther distances, thus expanding
the geographic scope of where cities can be located -
thereby creating greater possibilities for the creation of
city systems. Technology first led to the ability to house a
larger number of people in the same urban space as before
and therefore permitted an increase in city size through
densification. Technology then, as discussed in Chapter 2,
permitted the population of cities to spread out spatially
urban transition
is an inextricable
part of the demo-
graphic transition
and both are
related to advances
in modern
technology
the limits of
technology in the
preindustrial era
represented
constraints on the
location and size
of cities, and led to
a greater variety
in the organization
of social life
