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Location, Pattern, and
Structure of Cities
• Ranking Urban Centers: classified by
service offerings (not size)
– Hamlet: few services
– Village: dozens w/ more specialization
– Town: more services & specialization w/ a
hinterland (a.k.a. market area, or
surrounding service area)
– City: more specialization, larger hinterland,
greater centrality, has a CBD (central
business district, “downtown” or core)
– Megalopolis – where large metropolitan
areas have grown together (Bosnywash,
DFW)
• Situation and Site
– Situation: position relative to travel routes,
farmlands, manufacturing complexes,
towns, cities (near & distant surroundings);
subject to change: Chicago, Shenzhen
(favorable), “Rust Belt” (unfavorable)
– Site: physical qualities of a place; valley,
coastal plain, plateau, island,… Paris (first
established on the Seine River), Singapore
(separation from Malaysia)
• Central Places
– All urban centers have a certain economic
reach (range) and centrality
When Hong Kong became a Special Economic
Zone in China, Shenzhen became the fastest
growing city in the world.
• Central Place Theory
– Walter Christaller (1933); wanted to show
how & where urban areas would be
functionally & spatially distributed
– Assumptions: flat area, no barriers, even
soil fertility, even distribution of pop. and
purchasing power, uniform trans. network,
constant range of sale
– Central goods and services = provided only
at a central place, or city (available to
consumers in a surrounding region)
– Threshold – min. market needed to keep a
central place in business
• Range of sale = max. distance
people will travel for good or
service (economic reach)
• Complementary region =
exclusive hinterland w/ a
monopoly
• Hexagons – logically, the
complementary region would be
circular, but problems arise
(unserved or overlapping areas);
hexagons fit perfectly
• Nesting pattern (region-w/in-
region); relates to scale
Christaller’s Hierarchy of
Settlements & Service Areas
• John Borchert (1967): analyzed
urbanization in North America (4 epochs);
based on impact of transportation &
communication
– 1) Sail-Wagon Epoch (1790-1830)
– 2) Iron Horse Epoch (1830-70); steam-
powered locomotive
– 3) Steel-Rail Epoch (1870-1920); full impact
of Ind. Rev., hinterlands expand
– 4) Auto-Air-Amenity Epoch (1920-70); gas-
powered internal combustion engine
– 5) High Technology Epoch? (1970-); service
& information
• Models of Internal City
Structure – based on
competition among land
uses
• Concentric Zone Model
• Ernest Burgess (1920s);
Chicago: 1) CBD, 2) Zone
of transition (res.
deterioration & light ind.),
3) Blue-collar workers, 4)
Middle-class, 5) Suburban
ring
• Dynamic: city grows; inner
rings affect outer ones
Chicago in the 1920s
• Sector Model
• Homer Hoyt (1939);
criticized Burgess Model
as too simple & inaccurate
• Growth creates a pie-
shaped urban structure
• Low-rent areas could
extend from the CBD to
the outer edge (3)
• The same is true w/ high-
rent, transportation, and
industry
• Multiple Nuclei Model
• Chauncy Harris & Edward
Ullman (1945); neither of two
models are accurate
• CBD was losing its dominant
position as the nucleus of
the urban area
• Separate nuclei become
specialized and
differentiated, not located in
relation to any distance
attribute
– Urban Realms Model– Urban realms – parts of
giant conurbations; self-sufficient suburban sectors (focused on their own independent CBD)
– Edge cities (Garreau) –outer realms; third wave: 1) suburbanization after WWII, 2) malling of US (moving marketplace to suburbs in 1960s & 70s), 3) edge cities (moving jobs to suburbs in 1980s & 90s)
– Edge cities have extensive office & retail space, few residential buildings (not cities 30 years ago)
Urban Realms (and Edge Cities) of Los
Angeles
Global Urbanization
Europe is the most urban continent, while Africa is urbanizing most quickly.
• Combines radial sectors & conc. zones, growing rapidly
• CBD – market & high-rise sectors
• Commercial spine –extension of CBD; surrounded by elite res.
• Mall = edge city; suburban node
• Zone of Maturity –middle class
• In Situ Accretion – more modest housing
Griffin-Ford Model
• Outer-ring = poverty; dense pop.
• Periférico – squatter settlements; homes from discarded materials; unskilled & impoverished
• Disamenity sector –tenement apartment housing; also extremely poor; drug lords often “run the show”
• Gentrification zone –rehabilitation of inner-city; historic buildings may be preserved
Cuzco, Peru
La Paz, Bolivia
• SE Asian City; T.G. McGee Model
• Hybrid of sectors & zones, growing rapidly
• Old colonial port zone & commercial district are city’s focus
• No formal CBD; separate clusters: gov’t zone, West. comm. zone (practically a CBD in itself), alien comm. zone (mostly Chinese), and mixed land-use zone (misc. economic activities, including light industry)
• Market gardening zone – along periphery
• New industrial park (estate) – farther out
• Residential areas tend to get poorer away from the port zone (similar to Latin-American city)
Singapore
Shanghai
Bangkok
0
5
10
15
20
25
30
Tokyo New
York
Mexico
City
Mumbai Lagos
1975
2000
2015
The World’s Largest Metropolitan Areas
• Megacities – primarily in LDCs; Mumbai, India; Lagos,
Nigeria; Dhaka, Bang.; Karachi, Pak.,… Tokyo, Japan
(MDC; 26)
• Africa is urbanizing the fastest, followed by S. Asia, E.
Asia, then S. and Cent. America
• Many LDCs lack enforceable zoning laws, residents are crowded together into overpopulated tenements & slums
• Cities in the Developing World– Squatter settlements & shantytowns
encircling megacities (e.g. Lagos, Mumbai, Cape Town,…) may appear homogeneous, but have their own ethnic neighborhoods
– City govt’s lack resources for adequate education, housing, police, or medical facilities
– Informal economy – work not taxed or calculated by govt’s (urban immigrants in shantytowns)
– Remittances – part of a person’s income sent back home, becomes a mainstay for those left behind
• Urbanization: Pro & Con
– Pro: 1)fewer people in rural areas – better for forests, soil, wildlife,…,
2)lower family sizes, better education, better health
3) Economies in more urban countries tend to be more developed
– Con:1) Hazards of Site – outlying areas more susceptible to landslides, floods, storms, earthquakes,…
2) Loss of Land – farmland lost (US = 1 million acres/yr.; China = 3x as much)
3) Changed Land Cover – natural landscape becomes cultural (pavement, buildings,…); less rainfall, more pollutants
4) Impact of Pollution – growing volumes of contaminants (in air, water, and soil); Mexico City, Delhi, Bangkok are most smog-ridden
5) Production of Waste – lack of sewer facilities (>3 million w/o in Mexico City); burning garbage heaps
6) Larger Demand for Water – much higher than in rural areas; riverfront cities create pollution as well
7) Changing Consumption Habits – urban dwellers use more energy, change diets (meat), dress, and recreation habits
The ratio of urban to rural dwellers is steadily increasing. By 2015
more than half of the world's population will be urban. The number
of people living in mega-cities—those containing more than 10
million inhabitants—will double to more than 400 million.