Settings and forms of urban regions 287City on a peninsula. Manado (Indonesia), Freetown (Sierra Leone), Mon-
rovia (Liberia), Beira (Mozambique)
Coastal city on a strip between water bodies or mountain ranges.Miami, Kobe
(Japan)
City just upriver from coast, typically subject to f loodwaters from both directions.
Bangkok, London, Sapporo, Kuala LumpurMetro area and urban-region ring
Theinner-edge-and-hole of the donut modelalso tells us much about an
urban region. Thus a large expanding metropolitan area in the center tends to
squeeze a narrow urban-region ring, which sometimes is also squeezed by urban-
ization in an adjoining region. Narrow rings are limited in resources, such as
appropriate space for a water-supply source, sufficient recreation/tourism sites,
asuitable heavy-industry-center location, market-gardening areas, biodiversity-
rich large natural areas, and differing farmland landscapes. More generally, nar-
row rings around a large metro area lack flexibility and stability for a region’s
future.
Interestingly, the edge or border between metro area and urban-region ring
is a useful indicator of key flows and movements in the region (Forman1995). A
compact metro area may largely result from a greenbelt or urban growth bound-
ary or certain transportation planning. Compact metro areas may have much
movement within them, but relatively little or modest radial movement out to,
and in from, nearby unbuilt areas. As a consequence, the nearby surrounding
urban-region ring seems to maintain its own functioning land-use integrity.
In contrast, a metro area with several or many prominent built lobes
and greenspace wedges suggests considerable interaction in radial directions
between metro area and urban-region ring. People living in the city have ready
walking/biking access to greenspace that connects them to surrounding coun-
tryside for recreation. Conversely, wildlife and other species use the coves to
continually move inward and enrich city parks. The cooling effect of greenspace
wedges minimizes a city’s heat-island effect, and wind channeled along certain
coves helps keep the city’s air clean. Also, built lobes usually contain significant
radial transportation routes connecting city and surroundings.
The compact form of a metro area may result in part from the absence of
amajorring highway. Ring highways seem to open up the surrounding inner
portion of the urban-region ring to development. A diffuse metro area border
often results. The diffuse border suggests the presence of an intensive network
of local roads, perhaps a sprawl of homes on relatively large lots, extensive
habitat loss, fragmentation of natural areas, proliferation of non-native species,