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Chapter 11 - Urban Systems and Urban Structures. The nature of cities in an urbanizing world: origins, definitions and locations The economic base and systems of cities: functions, hierarchies, and networks Inside the city: land uses, social areas, and patterns of change
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Chapter 11 - Urban Systems and Urban Structures The nature of cities in an urbanizing world: origins, definitions and locations The economic base and systems of cities: functions, hierarchies, and networks Inside the city: land uses, social areas, and patterns of change World urban diversity: cities in Anglo America, Europe, and the developing world 11.1, 11.2
Megacities and Merging Metropolises • Megacity: > 20 million pop. metropolises - from personal choice and government investment decision. (11.3, 11.4) • 4% world pop lives in cities of 10 million or more (11.5) • Merged to “Conurbations”- multiple centers.The major conurbations in N America “Megalopolis” called BosNyWash. • Megalopolis and other Angle American Conurbations (11.6).
Settlement Roots • Most rural people live in village, or hamlet. Only W.Europe, Americas (except Mormon Utah and Mennonite Manitoba), Australia and New Zealand - live apart. • Cooperative and utopian community - Oneida (NY), Amana (IA), and New Harmony (IN) • Rural settlement forms (11.7, 11.8 and 11.9) • Trade - tendency for linear clustered houses along main streets.
Nature of Cities • Urban units are not single type, structure or size, sharing common characteristics - nucleated and nonagricultural settlements. • City/Town - with CBD, (11.10) • Suburb - functionally specialized segment of a larger urban complex. Not self-sufficient. • Urbanized area - continuous built-up landscape defined by building and population densities with no reference to political boundaries. • Metropolitan area - large-scale functional entity. Current Federal Definition: MSAs (Metropolitan Statistical Areas) economically integrated urbanized areas in one or more contiguous counties. (11.11)
Location of Urban Settlement • Site - absolute location, such as break-of-bulk, bayhead, railhead (end of railroad), waterpower cities, island, elevated cities,... (1.9, 1.10, page 10) • Situation - relative location - places a settlement in relation to the physical and cultural characteristics of surrounding areas. • The site or situation originally gave rise to an urban unit may not remain the essential ingredient for its growth and development for very long. Circular and cumulative causation - a successful urban unit may acquire new populations and functions attracted by the already exiting markets, labor force, and urban facilities.
Economic Base • City support itself or provides services and products for its hinterland. • Basic Sector - “export” service/products to outsides • Nonbasic sector - support themselves in the city. • Total economic structure of an urban area = basic+nonbasic • Functional specialization of urban areas (11.12) • Ratio tends to grow (basic/nonbasic) to 1/2 in a 1 million city • multiplier effect - (11.13) • The growth of cities may be self-generating “circular and cumulative” -service industry (bank and retailing service, public) - add more labor needs to nonbasic sector. • declining trend in NE and Midwest (Fig. 11.14 and Table 11.1)
Urban Hierarchy • Ranking of cities based on size and functional complexity • E.g. 12 million in largest city, then the second largest city will have 6 million, and third largest will have 4 million (1/3 of the largest city)….. The difference becomes smaller at lower levels of the hierarchy. • This rule doesn’t apply to countries with dominant city such as France and Mexico. • Primate City - far more than twice the size the second-ranked city - Seoul in Korea and Luanda in Angola - express the heritage of their culture or colonial imprints. (11.17- primate city evolution) • World Cities (11.18) • Urban Influence Zones - area outside of a city that are still affected by it (Baxter, Algood)
Central Place Theory - Walter Christaller • Assumption - 1) no topographic barriers, channelization of traffic and variations in farm productivity • 2) even population distribution pattern • 3) same purchasing power, tastes and demands • 4) minimum number of customers • 5) shortest distance demand • Results - 1) sales monopoly in each polygon 2) no userved areas 3) central place at the center of hexagon 4) Largest centers provide enough service to the largest area 5) size of market area proportional to the number of goods and services offered from that place 6) smaller hexagon serves smaller area (11.18)
Christaller’s Hierarchy of Settlements and Service AreasT=towns, C=city,H=hamlet,V=village • Nesting pattern • each larger complementary regions is centered on a higher-order urban place • Rank-size population
Conclusions from Hexagon Model • Ranks of urban places do form an orderly hierarchy of central places in spatial balance, if one removed, new equilibrium will be formed. • Same distance apart for the city with same rank • Larger cities will be spaced farther from each other than smaller towns or villages • applicable to agricultural areas, new balanced network will form once a node is removed. • Supportive evidences found in Europe, N America and, North China Plain and Sichuan Basin, Midwest’s square layout confirmed Christaller’s model
Network City • Two or more cities - Partially complementary in functions, developing to a networking pattern • Kyoto (cultural capital), Osaka(commercial/industrial) and Kobe (leading port) joining together to compete with Tokyo as a major center of commerce • Europe - Amsterdam, Rotterdam, and The Hague – “the Randstad” • No true US network city.
Urban systems and urban structures Competitive Bidding for Land Usable land are scarce commodity. “Rent-paying ability” to allocate the land usage. Ideally, the most desirable and efficient location where the max possible interchange could be achieved. The attractiveness of a parcel is rated by its relative accessibility to all other land uses of the city. (store - customers, residents...) Convergence of the city core make it more accessible. 11.2 shows the transit junction points are more desirable than others. Urban land use pattern 11.23 Population density pattern (11.24)- shows a comparable distance decay arrangement with one important variation (hollow at the center) As pop grows, second center competing for customers and industry, high-speed transportation available. (11.25)
Models of Urban Land Use Structure • Concentric zone model (11.26a) - explain the sociological patterning of American cities in 20s. 4 residential rings -a) lower-class b) independent working class homes c) single-family wealthy,afford the longer commute. d) Just emerging commuters’ zone when this model was proposed. • Sector Model (11.26b) • Filtering Down process. High-rent residential areas are dominant in city expansion and grow outward from the center of the city along major arterials. • Middle-income housing sectors lie adjacent to the high-rent areas, and low-income residents occupy the remaining sectors of growth. • Fig 11.27 shows the Calgary (Canada) in sector model • Multiple-nuclei model (11.26c) • large cities developed by peripheral spread from several nodes of growth (LA)
Social Areas of Cities • The larger and more economically and socially complex cities are, the stronger is the tendency for their residents to segregate themselves into groups based on social status, family status, and ethnicity. • In US, high status - high income, college education, prof/managerial job and high house value. • Social status patterning agrees with the sector model. Fig 11.28 and 11.29 • Family Status - Dist. from the center increases -> avg. age of the adult declines and the size of their family increases. • Ethnicity - cultural segregation - more black in segregated neighborhoods in 90 than in 80 in large cities. South and West are much less segregated than those of the NE and Midwest
Governmental Controls • US - emphasize has been on land use planning, subdivision control and zoning ordinances, and building, health, and safety codes. • To minimize incompatibilities, public service locations waste disposal facilities.. • Criticized as devices to exclude from upper-income areas lower-income populations or those who would choose to build or occupy other forms of residences: government housing projects.. • Most Asia area without zoning practices - variety of building types from different eras.
Suburbanization in the U.S. • What caused it? Improvement of the automobile , 40-hour weekly hours, New Deal programs guaranteed mortgage, and veterans benefit programs • Between 50 and 70 - Metropolitanization and suburbanization. • Modern urban models (11.31) high-income residential use continued their outward extension beyond the central city limits, usurping the most scenic and most desirable suburban areas and segregating them by price and zoning restrictions. • By 90s, suburban centers become self-support out cities, performs many tertiary and quaternary services - edge cities - “galactic”: galaxies of economic activity nodes organized primarily across the freeway systems (11.32) • Metropolitanization and suburbanization caused two central city patterns/problems – next slides
Central City Change • 20th Century - two city patterns and problems: 1) Constricted Central Cities (Eastern cities) - older and city and suburbs, unable to expand and absorb the new growth areas on their margins and to maintain the balanced, profitable economic and social base originally theirs. redistribution of population caused by suburbanization resulted not only in the spatial but also in the political segregation of social groups of the metropolitan area. The service needed to support the poor include welfare payments, social workers, extra police and fire protection, health delivery systems, and subsidized housing. But central city are unable to support such needs 2) Expanding Central Cities - new U.S. cities (Western cities) developed in the automobile era, faced problems of providing infrastructure, services and environmental protection to an even-more sprawled residential and functional base.
Gentrification (Eastern cities) • Gentrification - the rehabilitation of housing in the oldest and now deteriorated inner-city areas by middle- and high-income groups (11.34) (from Boston to Savannah,Georgia) • Milwaukee built a riverside walk and attracted $50 million investment. • Denver’s LoDo • Cabbagetown in Atlanta • Chatham Arch in Indianapolis
Expanding Central Cities • 90% of westerners live in city in 2000. (11.35) • Six of 10 fastest growing U.S. metro areas are in the West. • Speed and volume of growth generated concerns: central cities can support infrastructure service from unrestricted growth. • Increasingly, central cities and metro areas of E and West are seeking to restrain rather than encourage physical growth. Oregon drew a “do not pass” line around itself in the late 70s, prohibiting urban conversion of surrounding forests, farmlands, and open space. • “Smart growth” program in Colorado, Delaware, Minnesota, and Washington.
Anglo American City • Canadian cities are more compact, higher density of building and people and lesser degree of suburbanization of population and functions. (11.36) (Canadians are 2.5 times more dependent on public transit than are Americans in city). 1/4 the number of miles of expressway lanes per capita as US metropolises. • Greater social stability in Canadian cities, higher income more retention of shopping facilities, more employment opportunities and urban amenities. • Less competition form “edge cities” in Canadian metro areas.
West European City • Heritage of medieval origin, Renaissance restructurings, and industrial period extensions has given to the cities of W Europe features distinctly different from those of cities in other regions founded by European immigrants • More compact and take less area than American cities; most are apartment dwellers, narrow street no yards. • No suburban sprawl. • Low skylines (11.37) • Well-developed public transportation (subway). Auto is not universal need in Europe as in the U.S. • 11.38 - historical core: middle class, self-employed, and the older generation of skilled artisans share limited space with preserved historic buildings, monuments and tourist attractions.
East European City • Compact with high buildings and pop. density, with a sharp break between urban and rural land uses on its margins. Depended nearly exclusively on public transit. • Land use determined by government not market. • Central Cultural District (CCD) reserved for public use, nearby space was provided for recreational and commemorative park. • Microdistricts (residential areas) - uniform apartment blocks housing 10,000 to 15,000 persons, surrounded by broad boulevards (11.39a) • Market driven pattern will emerge later.
Cities in Developing World • Experienced disproportionate population concentrations in capitals. Primate cities dominate urban systems. Pop. attracted to cities from rural. Squatter districts accommodate increasing immigrants from rural - create an inverse concentric zone pattern where the elite and upper class reside in central areas and social status declines with increasing distance from the center. (models in 11.43)
African Cities • Less easily generalized. The least urbanized segment of the developing world in Sub-Saharan Africa with fastest urban growth rate. • Future urban expansion comes from rural to urban migration and the incorporation of villages into spreading metropolitan complexes. • European colonists created new centers of administration and exploitation like Asian colonized cities. • Spatial contrasts in social geography are great. Ethnically-based subdivisions are seen.
Latin American City • “City Life” - the culture norm in Latin America. Mostly live in primate cities. (11.43d) • Most jobs in downtown. Lives in city or edges commuting to work. • Two parts - modernized CBD and traditional “market” segment of small, street-oriented business and shops. • “Spine” - continuation of the features of the city center outward along the main wide boulevard (upper-middle-class housing) - connecting to the mall (at the end of the elite commercial spine). A ring highway (periferico) - connect the mall and developing industrial parks • Three established residential districts arranged in concentric rings around the core. Opposite of many US cities. • Barrios and Favelas (slums) - on the outskirts of the city. Upgrading house in the zone of “in situ accretion” when times are good.