Urban Patterns http: //mongabay. org/images/brazil/favela_01. gif http: //www. michaelhewes. com/personal_work/mhewe 002. jpg
Where Have Urban Areas Grown? • 1800, 3% world’s population was urban; Beijing was the only million city • 2000, 47% world’s population is urban; 400 million cities worldwide http: //www. nasa. gov/images/content/49259 main_flat_earth_nightm. jpe
Urbanization • The process by which the population of cities grow is known as urbanization – Increase in the number of people living in cities – And the increase in % of people living in cities within a country • 1800 = 3% world’s population urbanized • 1850 = 6% world’s population urbanized • 1900 = 14% world’s population urbanized • 1950 = 30% world’s population urbanized • 2000 = 47% world’s population urbanized
Percent Urban
Global Patterns • • MDCs – 75% urbanized LDCs – 40% urbanized Latin America – ~73% urbanized Except for Latin America, the level of urbanization reflects the level of development • Industrialized countries are highly urbanized because of the clustering of manufacturing industry • However rapid urbanization rates in LDCs are caused by rural-urban migration and high natural increase rates, not industrialization
Most Populous Cities 2004 http: //www. ucar. edu/communications/staffnotes/0506/images/World_population. jpg
Million Cities
Defining Urban Settlements • During the 1930's, Louis Wirth argued that people living in urban areas led a different kind of life than people in rural areas. He believed that human sociology was affected by three characteristics of urban areas: – Large size – contractual rather than social/familial relationships – High density – specialization of labour in urban jobs – Social heterogeneity – great variety of people
Physical Definition of Urban Settlements • Legal: city is an urban settlement that has been legally incorporated into an independent, selfgoverning unit • Urbanized area: contiguous built-up area • Metropolitan Statistical Area (MSA): the sphere of influence of a city goes beyond the legal and urbanized boundaries – a MSA is – Urbanized with a population > 50, 000 – Contained in the county in which it’s located – Is adjacent to counties with high population densities
St. Louis
Physical Definition of Urban Settlements (cont. ) • Micropolitan statistical areas: – 10, 000 – 50, 000 inhabitants – Includes county and adjacent counties • MSAs may overlap – E. g. : BOSNYWASH corridor – A large continuous urban area flowing from one city to another is called a megalopolis • CBDs of the cities are distinct • But the peripheries are difficult to determine
US Megalopolises http: //www. tea. state. tx. us/student. assessment/resources/online/2003/grade 10/ss/p 76 no 8. gif European example: Ruhr (Dortmund, Düsseldorf & Essen) Asian example: Tokyo-Yokohama
Where are People Distributed Within Urban Areas? • People are distributed according to the way they cluster in specific neighbourhoods according to their social characteristics • 3 models have been developed to explain the internal structure of urban areas • All were based on Chicago, Illinois and were later applied to cities elsewhere in North America
Burgess – Concentric Zone Model According to the model (1923), a city grows outward from the central area in a series of concentric rings
Hoyt – Sector Model • According to the model the city develops in series of sectors or wedges
Harris & Ullman - Multiple Nuclei Model • According to the model, a city is a complex structure with more than one centre around which activities evolve • Certain nodes attract certain land uses and incompatible land uses repel each other and locate far apart
Garreau – Edge City • According to the edge city model by Joel Garreau, nodes form in response to the rapid development of cities at major suburban freeway interchanges • Many say edge cities “have it all; ” they are characteristically composed of office parks, shopping malls, industrial districts, and service centers located near major highways • The edge cities are very new; about 30 years ago they were villages or rural farmland • At present they are homes to the largest retail locations containing more than 600, 000 ft² of retail space. The area also contains more than 5 million ft² of office space • There are more jobs than homes in the edge cities • Edge cities often lack local government and may also be unincorporated.
Edge Cities The central city is surrounded by a ring road, around which are suburban areas and edge cities, shopping malls, office parks, industrial areas, and service complexes.
Mann’s Model of a Typical British City
The European City Low-class residential in the outskirts or suburbs – long commutes to jobs • E. g. : Paris, France High class residential close to CBD – access to boutiques, parks, cafes, opera http: //www. worldbook. com/wc/assets/around_world_gfx/paris_map 02. gif http: //www. theage. com. au/ffximage/2005/06/07/paris_view_wideweb__430 x 297. jpg
Griffin & Ford - Latin American Model – Zone of maturity (better houses – colonial, paved streets, street lighting, good transport, schools and sewage. ) – Zone of in situ accretion – mixed quality of housing, only main streets paved, some schools but not universal electricity. – Zone of peripheral squatter settlements – makeshift shanty houses, high unemployment, poverty, no basic services (such as piped clean water, sewage, paved roads. )
Sao Paulo, Brazil Wealthy live near CBD in high rises http: //idol. union. edu/~micklasc/Brazil/new_pa 1. jpg A favela is a squatter settlement or shanty town. It is also known as a barrio. They have few services, although some areas are quite well organized. 30% (L. Am) 60%+ (Africa) Poor live in favelas on the city perimeter
Fès (Fez), Morocco • The old city has narrow winding streets and dense population. The French laid out a new district to the west with a geometric street pattern.
Why do Inner Cities have Distinctive Problems? • Inner cities in the United States contain concentrations of low income people with a variety of physical, social, and economic problems very different from those faced by suburban residents.
Inner City Physical Problems • Poor condition of housing as lower income families struggle to maintain homes • Filtering: subdivision of former wealthy homes into multiple dwellings for families – may be neglected by landlords and abandoned by families • Redlining: some banks draw red lines on a map to delimit areas where they refuse to lend money – illegal under Community Reinvestment Act
Urban Renewal • Demolition of condemned buildings followed by reconstruction by private developers or public agencies • Public Housing has replaced many substandard dwellings • Public housing is reserved for low income households – US (2% of all dwellings); UK (30%+)
Inner City Public Housing Projects http: //tigger. uic. edu/depts/ahaa/imagebase/maclean/aerials 3/087. JPEG
Public Housing • 1950’s/60’s high rise housing projects have proven unsatisfactory for families: – Broken elevators – Juvenile gangs terrorizing families – High drug use and crime rate • More recently low rise apartments & row houses have replaced high rises • Scattered-site in which low-income housing is scattered throughout the city rather than clustered in a large project • Reduced supply of public housing despite increased demand
Urban Renewal Case Study • A nonprofit organization called Mi Casa buys and renovates dilapidated city buildings and sells them at below-market rates to families of modest means. www. thisoldhouse. com
Gentrification • In some cases, middle class people buy and renovate deteriorated inner city housing – gentrification • Houses are attractive – – – Larger, well-built homes, but cheaper Character homes with architectural details Close to downtown – lesser commute Closer to theatres, cafes, restaurants Grants offered by the City to renovate DINKUM – no concerns about inner-city schools • BUT displaces lower income families who can no longer afford rentals in the area
Inner City Social Problems • Poverty is the leading social issue • Underclass suffer from high rates of – – – – Unemployment (lack of job skills & education) Alcoholism (addiction & despondency) Drug addiction (hopelessness) Illiteracy (school drop outs) Juvenile delinquency (territoriality) Crime (sometimes gang related) Homelessness (no job, family problems) Ethnic & racial segregation (African American & Hispanics) • Schools are run-down & public amenities (clinics, hospitals, policing) are inadequate
Inner City Economic Problems • Inner city residents cannot afford to pay the taxes required to support services • Cities can – Reduce some services to pay for others – Raise tax revenues by attracting redevelopment of luxury dwellings – drives lower income people away – Annexation – legally adding land to a city – Rural residents on city peripheries favoured annexation because of the improved public services – results in urban sprawl http: //www. cartoonstock. com/newscartoons/cartoonists/mba/lowres/mban 269 l. jpg
Why do Suburbs have Distinctive Problems? • USA, 1950 20% Americans suburbanized • 2000, 50% American suburbanized • Suburbs attractive – Single detached family dwellings – Larger lots with gardens for children – Space for parking – Cleaner air, quieter – Lower crime rates, safer
Suburban Developmentin the U. S. and U. K. New housing in the U. K. is likely to be in planned new towns, while in the U. S. growth occurs in discontinuous developments.
Problems of Suburbs • The peripheral model – Density gradient • Density declines with increased distance from the city centre • Changed – decrease in density in CBD; increase in suburbs (subdivisions) – Cost of suburban sprawl • Competition for land; cost of infrastructure; loss of farmland; traffic pollution • Suburban segregation Residents isolated from commercial & industrial areas; social class isolation; zoning ordinances separate land use functions
Problems of Suburbs • Transportation and suburbanization – Motor vehicles • Dependence on cars; transportation networks and parking lots require land; traffic congestion; rush hour – Public transportation • Declined in public ridership in US (less convenient); LRT on the increase – subsidized & encouraged; low income can ill afford public transit to reach jobs in suburbs • Local government fragmentation (difficult to solve regional problems) – Metropolitan government (e. g. : CRD in Victoria – 14 municipalities; 1 federation) – Growing smart (Smart Growth) • Curb sprawl; reduce traffic congestion; reverse inner city decline • Achieved through urban in-filling; increasing densities; subdivisions; urban revitalization
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