Uploaded by Vinay naik

Urbanization PPT

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URBAN Geography - Intro
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Urbanization = an increase in…..
• the # of people living in cities
• the % of people living in cities
• The literal physical building up of cities
• Stats…..
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1800
1850
1900
1950
2000
2025
–
–
–
–
–
–
3%
6%
14%
30%
47%
61%
Urbanization – Intro – cont’d
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Urbanization is a measure of
development (abundant AG tech,
people leave rural areas for cities for
work and services)
• MDCs - @75% urban
• LDCs - @40 % urban
• BUT LDCs contain most of world’s
largest cities (6 of top 10 in LDCs)
• i.e. MDCs have highest levels of
urbanization, LDCs have highest rates
Urbanization – Intro – cont’d
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LDCs = mega cities: rapid pop
growth and migration to cities has
caused explosion of urban growth in
LDCs. LDCs cannot support booming
growth.
Mega cities plagued by chaotic,
unplanned growth…no jobs, poor
infrastructure, inadequate housing,
urban squalor, horrible pollution,
poverty, squatter settlements
Mega Cities –
MX City and Mumbai, India
Urbanization – Intro – cont’d
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MDCs = world cities – worldwide
centers of econ, pol, cultural activity
and influence.
• Top tier = econ and cultural
powerhouses…NYC, London, Tokyo
• Second tier….
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Govn’t Seats – DC, Moscow, Paris
Pop Culture – LA, Mumbai
Industrial Centers – MX City, Sao Paulo
World Cities – Tokyo and
London
Defining Urban Settlements
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Where does “the city” begin??
Social distinctions betwn
urban/rural…..Cities have
• Lots of people most of whom are
anonymous
• High pop density
• Job specialization
• Social heterogeneity (diverse)
Physical Distinction Betwn Urban
and Rural
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City Center: legal boundary (i.e. DC
proper). Independent and self
governing unit (city officials, taxes,
providing services, etc.)
Urbanized Area: central city +
surrounding suburbs (i.e. Arlington,
Herndon = urbanized area of DC)
Physical Distinction Betwn Urban
and Rural
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Metropolitan Statistical Area (MSA):
the functional area/region of a city –
i.e.. its zone of influence
Megalopolis: When MSAs overlap and
create one continuous highly
urbanized complex. Ex: from Boston
to DC = Boswash Corridor
Boswash Corridor - Megalopolis
Central Business District CBD
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CBD = city center/historic downtown
within the central city
• CBD is compact – less than 1% of urban
area but has large %% of shops,
offices, public institutions, sports
complexes, etc.
• Historically services were in CDB but
today have moved to suburbs
CBD
• Land value in CBD is extremely high
• Demand for space leads to sky
scrapers…since cannot build out you
build up – unique skylines
• Little manufacturing in CBD (not enough
land)
• Few people actually live in CBD (rent
too high)
Spatial Organization of Urban
Areas
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People and activities in cities are not
distributed randomly – they
concentrate in particular places
depending on their social
characteristics
3 prominent models explain city
organization…..
Concentric Zone Model
• Dev in 1923 by E.W. Burgess
• Based on Chicago
• Concentric rings of dev coming outward from
the core (CBD)
• Each ring = diff types of dev and econ
activities
• Land value decreases as you move out
• Model based on process of invasion and
succession – newest immigrants move into old
housing near city center and push earlier
groups outward
Concentric Zone Model
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Zones…
• 1.) CBD – non
residential activities
• 2.) Transition Zone –
industry and poor
quality housing (newest
immigrants)
• Industrial Workers’
houses – working class
• Middle Class/better
homes
• Commuter Zone – high
class residencies
Sector Model
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Dev in 1933 by Homer Hoyt
Also based on Chicago
Says city dev in sectors not rings.
Sectors radiate out from CBD like
spokes on a wheel
Activities expand in wedges
Seems to work better for Latin
American cities (MX City fits sector
model)
Hoyt Sector Model
Multiple Nuclei Model
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1945 – Harris and Ullman
City doesn’t have just one central
core but many nodes of business and
cultural activity
Los Angeles = classic example – no
real downtown but instead many
independent nodes of high land value
and business activity – Santa
Monica, Pasadena, Hollywood, etc.
LA – Multiple Nuclei
Multiple Nuclei Model
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This is a better model for cities built
mostly after WW II and post auto
dependent. Older cites built b/f auto
are more compact w/ real downtown
(CBD). Newer cities have more
sprawl and multiple nuclei.
*** NO city matches any one model
perfectly
City Models
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To use models for data mush have
good data – Census Tracts – cities
divided into about 5,000 resident
census tract sections (often follow
neighborhood lines). Every 10 yrs
gather info about people in that tract
(race, age, median income,
occupation, level of education, etc.)
Criticisms of Models
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1.) Models too simplistic and fail to
consider all of the varied and
complicated reasons that cause
people to select a certain location
2.) all 3 models created in U.S.
between world wars – are they
relevant to other countries and are
they still relevant today?
Inner City Problems
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In U.S. cities greatest contrast is
betwn suburbs and inner city
Ghettoization: process of inner city
decay
Problems……..
Inner City Problems
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Old, poor quality housing
• Filtering – subdividing big old homes into
several apartments and use for low income
rent
• Redlining: banks draw lines on map and refuse
to loan $$ within
• Public housing projects (subsidized – pay 30%
of income in rent) –run by govnt…poorly
maintained, drugs, crime, violence, gangs,
high density, culture of poverty, etc.
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Scattered public housing – pros/cons?
Inner City Problems
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Chicago housing
projects….
government
subsidized housing
Inner City Problems
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2.) Social Problems
• Permanent underclass – trapped in
perpetual cycle (unemployment, teen
pregnancy, drugs, gangs, single
parents, welfare, high school dropout,
etc. Can you get out? (There Are No
Children Here)
• Racial and ethnic segregation –
disproportionate minority representation
Inner City Problems – cont’d
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3.) Economic Problems
• Often lacks adequate public services
and lacks tax base to pay for them (i.e.
schools, roads, etc.)
• Annexation – legally adding land area to
a city’s boundaries. Most suburbs do
not want to be annexed in and rarely
happens anymore
Inner Cities – Urban Renewal
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Revitalization – new attempts to fix
up downtown…buy poor houses,
build new, shopping, cultural
attractions…try to b ring in young,
single professionals
Gentrification: process where inner
city neighborhoods turn into
expensive/fashionable urban districts
(squeezes out low income residents)
Problems of Suburbs
Rapid growth of Suburbs in 2nd half of 20th
C (i.e. auto, GI Bill, mass production of
housing)
 1950:
20% in suburbs
40% in central city
40% small towns/rural areas
2000:
50% in suburbs
30% in central city
20% small towns/rural areas
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Suburbs – cont’d
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Counter urbanization – net migration
from urban to rural areas (happening
in some parts of N. American and W.
Eur for first time). More people
moving to rural areas than are
leaving.
• Exurbanite: people who leave city to
move to suburbs or rural area
Suburbs – cont’d
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Urban Sprawl: goes hand and hand
w/ transportation…HUGE sprawl after
the automobile
• Older cities like NYC, pre-auto – densely
packed, narrow streets, lots of high rise
• Newer cities like LA, Atlanta – post auto
are sprawling areas with clogged
superhighways, multiple nuclei, and far
flung suburbs that operate
independently of each other
Suburbs – cont’d
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Suburbanization – is a process NOT a
place
• Began after WW II, mass phenomenon
by end of 20th C
• GI Bill, mass auto ownership, and mass
production of housing drives
suburbanization
Suburban Sprawl – cookie
cutter neighborhoods
Suburbs – cont’d
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Cons of Suburbs….
• Land hungry process – vanishing green,
encroaching on good AG land
• Lose unique sense of place – all are
cookie cutter alike (strip malls, chain
stores)
• Auto dependent and fuel consumption
(pollution)
• Rush hour commute
Suburban Commute
Suburbia - Homogenization
Suburbs – cont’d
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Suburban growth comes at expense
of inner city
• Erosion of tax base
• Segregation – poor, elderly, singles,
minorities in cities. Young families,
white, educated wealthier move to
suburbs. (Suburbs replace vertical seg)
• Spatial Segregation – rarely go to
other’s place
• Zoning also fuels segregation
Suburbs – cont’d
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Edge Cities: urban sprawl sometimes
takes the form of edge cities
• Located on outskirts of larger cities and
come to serve many of same functions
as large city
• Often located off a beltway surrounding
main city
• Classic ex: Tyson’s Corner
Smart Growth/Urban Growth
Boundaries
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Limit sprawl through long range
planning and efficient transportation
Promote compact and contiguous
dev (i.e. fill in the gaps)
Protect farmland, recreation, wildlife
Set growth boundaries
In U.S. – MD, OR, NJ, RI, and WA
lead the way w/ smart growth
Central Place Theory
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Theory developed by Walter Christaller in
1930s in Germany. Looks at relationship
betwn cities and surrounding communities
based on people’s demands for goods and
services
• Central Place: place (big city) people travel to
make purchases
• Market Area: areas people travel from for
purchases (i.e. the functional region of the
central place)….where do you go to buy
groceries, a car, medical treatment, etc.?
Central Place Visual
Central Place Theory
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Large cities are the econ hubs for their
region b/c they provide a great variety of
goods and services not available in smaller
communities
Hinterlands: smaller towns in periphery of
big city/central place. People from
hinterland often travel to central place for
big city amenities (i.e. sports teams,
cultural events, restaurants, etc.). Small
towns in hinterland contain fewer goods
and services than central place.
Central Place Theory
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Size of Market Area….assume you
wanted to open a new store, how do
you determine 1.) if it will be
profitable and 2.) where the best
location is within the market?? The
answer to these questions varies for
all services based on range and
threshold.
Central Place Theory
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Range: maximum distance people
willing to travel for your service
• Often expressed in time not distance
• Short distances for groceries, long for
bball game. Short distance for gas,
long distance for medical treatment
• Must be modified if competing locations
provide same service
Central Place Theory
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Threshold: minimum number of
people needed to support a service
• How many customers do you need to
make a profit?
• Potential customers in a given areas
depend on the product (i.e. not a high
demand for a roller skate rink in a
retirement community)
Central Place Theory
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Low order central place functions:
have small range and threshold.
• Services obtained on regular basis
• Requires only a small market to be
profitable
• People unwilling to travel far to obtain it
• Ex: gas, groceries, movies, etc.
Central Place Theory
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High order central place function:
large range and large threshold
• Is required less frequently
• Requires a large market area (lots of
customers) to be profitable
• People willing to travel further to obtain
it
• Ex: pro ball team, special medical
services, museums, concerts, etc.
Central Place Theory
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The Gravity Model can predict
optimal location for service
• Directly related to # of people in the
area
• Inversely related to distance people
must travel to access it
Central Place Theory
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Therefore……
• Small settlements are limited to low
order functions (w/ small ranges and
thresholds and market areas) b/c too
few people live here
• Higher order functions are more likely to
be in big cities (central places) w/
enough people to support the larger
range, threshold, and market area
Rank Size Rule
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Ranking settlements from largest to
smallest in a country often produces
a pattern
Rank Size Rule:
• The country’s nth largest city is 1/n the
size of the population of the largest
• i.e. the 3rd largest city is 1/3 the size of
the largest
Rank Size Rule
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When plotted rank
size distribution is a
fairly straight line
(true for U.S.)
Works better for
MDC’s (LDC’s not
enough wealth in
society to pay for full
variety of services in
other cities)
If graph is not fairly
straight line it does
not fit rank size rule
Rank Size Rule
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Primate City: largest city has more
than 2X the second largest city (i.e.
big city = primate city)
• Ex: Paris is primate city – has 11 mill
and Lyon (next biggest) has 2 mill (rank
size rule says it should have 5.5 mill)
• Ex: London is primate city – has 11 mill
and Birmingham has 3 mill
• Look at Google images – rank size rule
Bid Rent Theory
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Land closest to
CDB is most
expensive
Pop density
greatest closest to
the CBD
Affects land use
Economic Base
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A city’s economic base includes its
basic and nonbasic industries…
• Basic industries: export primarily to
customers outside the settlement (ex:
Dell computer plant, BMW plant)
• Nonbasic industries: services whose
customers live within the same
community (public schools, restaurant,
movie theater)
Economic Base
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A city’s unique collection of basic
industries is its primary econ base.
Exporting basic industries brings $$$
to the local econ and stimulates
provisions for more nonbasic
consumer services for the
community. I.e. a new plant brings
in workers, families and stimulates
growth…new neighborhoods, schools,
shopping centers, etc.
Economic Base
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How to figure a city’s basic
industries?
• Compute % of workers in a particular
industry in a city
• Compare to % of all workers in the
country employed in that industry
• If % is higher in the city than it is a
basic industry for that city
Urban Planners
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Urban planners consider people’s
perceptions, feelings, behaviors,
patterns, etc. to make decisions
about future urban growth. They
always plan way ahead and
anticipate . Planners make decisions
@ highway locations, zoning, future
transportation networks, bridges and
overpasses, etc.
Urban Planners
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Planners are aware of 5 general rules
of people’s travel
• We make many more short trips than
long ones
• We worry little about distance when
close to home, but when a trip requires
travel further from home distance
becomes an important factor in deciding
whether or not to go
Urban Planners
• For adults, the longest trips tend to be
work related
• Transportation limits some spatial
behavior
• People avoid perceived hazards,
whether or not those hazards pose a
real threat
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