Central Place Theory

• Central place theory posits that market areas focus on a central settlement where exchange and services occur
• Settlement market areas (hinterlands) overlap at different scales
• Larger settlements have larger, less numerous market areas and offer services that consumers travel far for
• Smaller settlements have smaller, more numerous market areas with services closer to consumers

Walter Christaller's Research

• Walter Christaller's 1920s research identified a regular hierarchy of places, from hamlet to regional service-center city
• The hierarchy consists of seven levels
• Hexagons were used to represent individual market areas
• Smaller-scale patterns overlap with larger-scale hexagonal market areas

Threshold and Range

• Threshold is the minimum number of people needed to support a business, based partly on local earnings
• Range is the maximum distance people travel for a service, calculated in travel time
• Both are modified by income and travel time
• Traffic patterns are crucial for destination travel time

Agglomeration

• Agglomeration occurs when similar businesses cluster locally
• Silicon Valley's computer firms benefit from proximity to Stanford and NASA Ames
• Competition is common in populated markets
• Planning and zoning concentrate similar businesses
• Manufacturers and corporate services locate close for knowledge and labor sharing

Urban Origins

• Access to resources and transportation are key factors
• Resource nodes are towns founded on access to natural resources
• Transport nodes are settlements at intersections of transportation lines (oceans, rivers, roads, etc.)

Examples of Urban Origins

• Sacramento, California was founded as a resource node due to Gold
• San Francisco, California was founded as a transport node due to its port

Settlement Patterns

• Clustered rural settlements feature closely arranged residential and farm structures
• Common in Europe and New England, they reflect social interaction, common land use, and security among similar cultures
• Dispersed rural settlements have households separated by significant distances
• Found in the American South, Midwest, and Great Plains, lacking cultural ties on the agricultural frontier
• Circular settlements consist of homes around a central open space
• Found in medieval German and English towns, and tribal herding communities in sub-Saharan Africa
• Linear settlements follow a road or stream
• Common in French long lots

Site and Situation

• Site refers to a place's physical characteristics or absolute location
• Situation describes a place's relationship with other locations, or its relative location

Site and Situation Example

• New York City's site on a large harbor at the Hudson River's end gave it an economic advantage
• Economic site factors determine industry and service development potential

Housing and the Built Environment

• Built environment (schools, houses, etc.) is the most important spatial environment for most of the world's population
• WHO considers housing vital for health as it needs to be dry, safe, and warm
• Building codes ensure safe construction and maintenance
• Buildings should be away from floodplains and pollution
• Clean water and waste removal systems are essential
• It should be attractive and well maintained

Concentric Zone Model

• The Concentric Zone Model represents Anglo-American cities during industrialization
• The model was proposed in 1923 by Ernest Burgess

The 5 Rings of the Concentric Zone Model

• Central Business District (CBD): High-density commercial land use, skyscrapers, and peak land value intersection
• Industrial Zone: Low-density commercial land, factories, warehouses, and port facilities
• Inner City Housing: Close to work, ranging from tenements to townhouses
• Suburbs: Detached single-family homes, mostly middle to upper class
• Exurbs: Wealthy commuter zone with large country estates

Additional Points about the Concentric Zone Model

• Deindustrialization has led cities to rebuild industrial areas into festival landscapes
• Inner city housing has been renovated through gentrification
• The Victorian-era garden city movement inspired suburban homes with lawns for the middle class
• Farmland protection laws, acreage zoning, and development boundaries regulate suburban and exurban growth
• Bid-rent curve: Land prices increase exponentially toward the peak land value intersection

Sector Model

• The Sector Model combines industrial corridors and neighborhoods
• Used to depict ethnic variations in the city
• The CBD is in the center
• Industrial space is organized in a linear corridor along a transportation line
• Upper-class housing extends outward from the CBD
• Working-class neighborhoods radiate from the CBD along the industrial corridor (ethnic neighborhoods)
• Middle-class areas are broken into wide, separate areas radiating outward from downtown
• White flight occurs when people leave inner-city areas

Multiple-Nuclei Model

• The Multiple-Nuclei Model represents the urban landscape with neighborhoods and commercial corridors
• Suburban business districts form on the urban periphery
• Service industries follow suburban sprawl
• New industrial development is also on the periphery

Galactic City Model/Peripheral Model

• The Galactic City Model represents the post-industrial city with dispersed business districts
• Decentralization of the commercial urban landscape as the economy shifts to services
• Manufacturing facilities are smaller, requiring low-cost land
• Suburban retailing occurs in multiple locations
• Retail centers closer to the old CBD are older
• Retail centers at belt highway intersections are newer

Latin American City Model

• The Latin American City Model depicts common urban landscapes
• It serves as an example of the colonial city, showing the effect of European colonial rule on Latin American, African, and Asian cities
• Plaza: A central square reproducing European cities, surrounded by government, religion, and commerce
• The Commercial Spine: A main boulevard from the plaza to the outskirts
• Often with homes of wealthy merchants
• Now with office towers and condominiums
• The Zone of Elite Housing: Upper-class housing straddles the spine from the center
• Social status derived from homes along main avenues
• Wealthiest people live on the urban periphery

Latin American City Model cont.

• Zone of Maturity: Middle- to upper-class housing surrounds the CBD
• Laws of the Indies segregated housing in Spanish colonial settlements
• Zone of In Situ Accretion: Indigenous or mixed-descent people lived outside city limits in homes of timber and adobe
• Zone of Peripheral Squatter Settlements: Urban poor live in squatter settlements on the periphery
• Squatters settle on land they don't own, invading overnight to avoid repercussions.
• Makeshift homes using scrap materials are built
• Housing quality declines farther from the city, as do available utilities
• Land tenure is the legal right to the land
• Zones of Disamenity: Squatter communities near the city center, built on unsuitable land (hillsides, flood plains, etc.) due to availability and proximity to work

Southeast Asian City Model

• The Southeast Asian City Model was developed in 1967 by Terrence Garry McGee
• Many of the fastest growing and most densely populated cities in the world
• High-rise developments, including some of the tallest buildings in the world
• There is a strip of upper-class housing stemming from the center, middle class residential areas close to the inner city, and the presence of squatter settlements on the periphery
• Traditional CBD elements scattered throughout including the colonial port zone and centered around export business
• The Western commercial zone is functionally a CBD, populated primarily by Western businesses
• The alien commercial zone is dominated by Chinese merchants who live in the same buildings as their businesses

Sub-Saharan African City Model

• The Sub-Saharan African City Model was developed in 1968 by geographer Harm De Blij
• The center features three distinct CBDs that reflect its history
• The former colonial CBD is laid out on a grid, contains vertical development, and is connected by planned roads
• The traditional CBD is the center of commercial activity and has single-story architecture
• The market zone is an open-air area with informal business
• The mining and manufacturing zone is on the outskirts
• Informal satellite townships surrounding the mining and manufacturing areas are largely squatter settlements

International Urban Diversity

• Cities around the world have different urban forms and structures
• Western European cities are more compact
• Eastern Europe and former Soviet Union countries have Soviet era central planning
• Micro districts: Zones of uniform housing that provide worker housing near job sites
• Developing world cities have divergent forms due to religious makeup, colonial history, socialist influences, and other cultural and urban land-use influences

Suburbanization

• Detached single-family homes dominate the suburban landscape
• Suburbs are predominantly middle-class but contain some upper-class and lower-class neighborhoods
• The first suburban single-family homes appeared in the 1890s
• Original suburbs were populated by WASPs but became more integrated in the late 1960s-1980s
• In 2010, just over 50% of the U.S. population lived in suburbs
• Suburbs continue to expand outward

Home Mortgage Finance and Suburban Growth

• Post-WWII, homeownership increased due to federal home loan programs like the G.I. Bill
• FHA and public finance mortgage corporations increased available mortgages
• Factory-style housing construction (Levittowns) used prefabricated parts and specialized teams

Service Relocation in the Suburbs

• Suburban home construction prompted service providers to locate in suburban areas
• Suburban service providers featured food, family doctors, fuel, and auto repair, as well as dry cleaning and gift shops
• Deindustrialization and middle-class flight from the inner city prompted larger service providers to relocate to suburban areas
• Service providers realized much of their consumer base moved away from the old CBDs that had been the traditional service center
• Service firms realized their labor force was moving from the old CBD

Suburban Sprawl

• Suburban sprawl is the expansion of housing, transportation, and commercial development to undeveloped land on the urban periphery
• Suburban political anti-growth movements push for laws slowing suburban development and limiting new roads and highways.
• Counterurbanization: Inner-city or suburban residents move to rural areas to escape urban issues

Edge Cities

• The idea of edge cities was introduced by Joel Garreau in 1991
• Edge cities have at least 5 million square feet of office space, and 600,000 square feet of retail space
• They lack a city government, except when built atop an existing town
• They have high daytime and low nighttime populations and are located at transportation nodes or commuter corridors
• Edge city growth has largely increased lateral commuting and counter-commuting

City Types

• Colonial cities originated as colonial trade or administration centers
• These cities retained European-style buildings and street networks
• Newly independent governments have often changed street names and place-names to reflect local culture and social history
• Fall-line cities were ports upstream on coastal rivers where ocean-going ships could no longer navigate
• Fall-line marks the transition from tidal estuary to upland stream
• Used as economic break-in-bulk points where ships were offloaded and then packed with outgoing trade
• Medieval cities predate the European Renaissance (1400 C.E.)
• Originally settled during the Roman era and developed into significant centers of trade and population during the medieval period
• Gateway cities are places where immigrants enter the country
• They tend to have significant immigrant populations
• Entrepôts are port cities where goods are shipped in at one price and shipped out at a higher price due to a lack of customs duties
• They tend to become large centers of finance, warehousing, and global shipping trade

More City Types

• Megacity: A metropolitan area with more than 10 million people
• Megalopolis: The merging of urbanized areas of two or more cities
• Example: Tokaido (Tokyo, Yokohama)
• World city designations signify global centers for finance, trade, and commerce.
• First-order world cities are New York City, London, and Tokyo
• Primate city: The largest city in a country with at least twice the population of the country’s next largest city
• Urban primacy is sometimes blamed when there is uneven economic development within a country
• Rank-size rule: The nth largest city is 1/n the size of the country’s largest city.

Urban Society

• De facto segregation: Ethnic or racial segregation exists without legal enforcement
• Historically, de jure segregation existed such as Jim Crow laws against African Americans
• Chinatowns often originated as zones where Chinese, Filipino, and Japanese migrants were forced to live
• Redlining: Designating neighborhoods on company maps where mortgage and insurance applications would be automatically denied
• Restrictive covenants: Homeowners added special covenants to their home real estate titles, restricting future sale of a home to white-only buyers
• Racial steering: Directing non-whites to racially specific neighborhoods, regardless of income
• Blockbusting: Agents encouraged white homeowners to sell cheaply by creating the fear that minorities moving in would cause declining property values

Urban Social Change

• Neighborhoods follow an invasion and succession pattern where one group replaces another
• The percentage of female-headed households in urban areas has increased
• Women make up half of the urban labor force
• Women are increasingly equal to men in terms of pay, management positions, and political power

Urban Economies

• Gentrification: Economic reinvestment in existing real estate
• Deindustrialization left many older areas of cities neglected and economically depressed
• Gentrifiers have converted old homes and storefronts into attractive modern accommodations
• Gentrification has driven out low-income residents from the community as finding new homes often becomes difficult, and displaced elderly persons can become a costly social welfare program issue for city governments
• Whole cottage industries in gentrification have appeared

Urban Economic Growth

• Urban governments and investors are concerned with infrastructure requirements
• Economic growth occurs in urban areas where utilities, transportation, safety, health, and education needs are met
• Make the city attractive by hoping young, educated businesspeople and major service industry firms in high-paying fields like technology, commuting, research and development, media, and advertising will relocate downtown
• Companies tend to locate their offices near growth poles for their industry
• Economic multiplier effects around centers result in a multitude of companies and investment in computer hardware and software development

Urban Sustainability

• Sustainability of urban growth and development is measured in economic and environmental terms
• Political attitudes and practical considerations create problems for urban leaders and policymakers
• City governments must address economic sustainability in terms of public services
• Since deindustrialization, large city governments have had difficulty balancing depressed commercial tax revenues with high municipal service costs
• The key to combatting high costs of municipals is to combine the municipal governments of the core city with the multiple town governments of the surrounding suburbs

The Expense of Schools

• Property taxes often do not meet the cost and demand for high-quality schools
• Homeowners resist increased taxes by voting down school bond levies
• School systems are caught between a public that does not want to pay higher taxes and parents who demand higher-quality schools
• Local school districts are increasingly dependent on state governments to help meet funding needs

Urban Transportation

• Traffic congestion plagues many cities
• Public pressure on local politicians to come up with solutions restricts leaders due to road construction costs and federal clean air regulations
• Air pollution from cars has local (smog) and global (carbon dioxide emissions) environmental impacts
• Mass transit results in fewer cars, reduced emissions, and increased accessibility for low-income citizens

New Downtown Housing

• Environmentally beneficial because it stops suburban housing sprawl from encroaching on farmland or sensitive environments
• New downtown housing can also reduce transportation impacts, fossil fuel use, and air pollution by having workers live downtown close to their jobs
• Brownfield remediation is a process in which hazardous contaminants are removed or sealed off from former industrial sites
• Mixed-use buildings contain both housing and commercial space
• New Urbanism developments are common
• Zoning laws separate commercial and residential space
• The purchase and rental prices of many new downtown housing units are so high that only the upper-middle-class income-earners can afford to live there