Cities - Environmental Transformations - page 112

animal products of the Great West, transmute
them into their most marketable form, and speed
them on their way to dinner tables around the
world' (Cronon, 1991: 211). In addition to pigs and
cattle, Chicago also became a crucial processing,
storage and market place for grain (Cronon, 1991:
97-147). As a specialized centre for the collation
and transformation of agricultural produce,
the growth of Chicago into a major metropolis
was deeply interconnected with the wholesale
transformation of the soils and ecologies of the
American Midwest.
Cronon's analysis of Chicago provides us
with a very detailed analysis of the (often hidden)
connections that exist between urbanization and
environmental change. Moving beyond the specific
example of Chicago, however, it is helpful to think
of the relationships that exist between cities and
the environments on which they depend in more
general terms. The environmental Kuznets' Curve
offers a helpful starting point when trying to
understand urban-environment relations. The
environmental Kuznets' Curve is the bell-shaped

curve labelled 'metropolitan scale' in Figure 6.3
below. What this curve demonstrates is a general-
ized pattern of urban environmental relations
over time (see Marcotullio and McGranahan,
2007; Marcotullio, 2007). The general trend
suggested by this curve is that early forms of
urbanization (particularly in industrial cities) tend
to be characterized by increasing rates of environ-
mental degradation at a local scale (measured in
air pollution, resource use, water quality). At some
point, the curve suggests that cities pass through
some kind of transitional zone, after which, and
following a sustained period of economic growth,
the levels of local environmental degradation
associated with urbanization tend to decline.
While the environmental Kuznets' Curve is only
a generalized model of urban environmental
relations, the pattern it charts reflects the experi-
ence of many industrial cities.
There remains some debate concerning pre-
cisely what causes cities to go through a period
of transition in their environmental relations. It
could be that environmental improvements come

Figure 6.3 The (urban) environmental Kuznets' Curve and the impacts of cities on global environmental
issues
Source: Adapted from Marcotullio and McGranahan, 2007