Chapter 22: Sustainable Cities

22.1 What Are the Major Population Trends in Urban Areas?

Half of the World’s People Live in Urban Areas

  • Urbanization: The creation and growth of urban and suburban areas. it is measured as the percentage of the people in a country or in the world living in such areas
  • Urban growth
    • Natural increase, in immigration from rural areas
    • Pushed from rural areas to urban areas
    • Pulled to urban areas from rural areas
  • Four Major Trends
    • The proportion of the global population living in urban areas is increasing
    • The number and size of the urban regions are mushrooming
    • Megacities
    • Hypercitices
    • Urban growth is slower in developed countries
    • Poverty is becoming increasingly urbanized; most developing countries

Urbanization in the United States

  • Four phases between 1800 and 2008
    • Migration from rural areas to large central cities
    • Migration from large major cities to suburbs and smaller cities
    • Migration from North and East to South and West
    • Migration from cities and suburbs to developed rural areas
  • Environmental problems decreasing
  • Older cities
    • Deteriorating services
    • Aging infrastructures

Urban Sprawl Gobbles Up the Countryside

  • Urban Sprawl: The growth of low-density development on the edges of cities and towns
    • Is eliminating surrounding agricultural and wildlands
    • The far-flung hodgepodge of buildings loosely connected only by highways
  • Contributing factors to urban sprawl in the U.S.
    • Ample land
    • Federal government loans
    • Low-cost gasoline; highways
    • Tax laws encouraged home ownership
    • State and local zoning laws
    • Multiple political jurisdictions: poor urban planning
  • Megalopolis: chain of roughly adjacent metropolitan areas; very large cities
    • Bowash

Urban Sprawl

Land and Biodiversity

  • Loss of cropland
  • Loss of forests and grasslands
  • Loss of wetlands
  • Loss and fragmentation of wildlife habitats

Water

  • Increased use of surface water and groundwater
  • Increased runoff and flooding
  • Increased surface water and groundwater pollution
  • Decreased natural sewage treatment

Energy, Air, and Climate

  • Increased energy use and waste
  • Increased air pollution
  • Increased greenhouse gas emissions
  • Enhanced global warming

Economic Effects

  • The decline of downtown Loss of forests and business districts
  • Increased unemployment in the central city
  • Loss of tax base in the central city

22.2 What Are the Major Urban Resource and Environmental Problems?

Urbanization Has Advantages

  • Centers of…
    • Economic development
    • Innovation
    • Education
    • Technological advances
    • Jobs
  • Urban residents tend to live longer and have a lower infant mortality rate- better access to medical care, family planning, and social services
  • Environmental advantages: recycling is more feasible, reduces stress on wildlife, and saves energy when relying on mass transit

Urbanization Has Disadvantages

  • Huge ecological footprints: consume most of Earth’s resources and produces most of the carbon dioxide emissions, high resource input of food, water, and materials resulting in high waste output
  • Lack of vegetation: vegetation is destroyed to make way for roads, buildings, and housing therefore cities do not benefit from the natural absorption of air pollution, oxygen output, and shade
  • Water problems: water demands increase, deeper well drilling, flooding due to a lot of impermeable surfaces, and destroyed wetlands
  • Concentrate pollution and health problems: pollution levels are higher because pollution is produced in a smaller area and cannot be dispersed and diluted
  • Excessive noise: urban dwellers are subject to noise pollution- any unwanted or harmful sound that interferes with hearing, causes stress, etc
  • Different climates experience light pollution: cities are generally warmer, rainier, and cloudier; the enormous amount of heat is generated by factories, lights, air conditioners, etc.

Life Is a Desperate Struggle for the Urban Poor in Developing Countries

  • Slums: areas dominated by tenements and rooming houses where several people may live in a single room
  • Shantytowns: shacks are built on the outskirts of town Squatter
  • Settlements: people take unoccupied land without permission for survival
  • Terrible living conditions

22.3 How Does Transportation Affect Urban Environmental Impacts?

Cities Can Grow Outward or Upward

  • Compact Cities: high density like Hong Kong, Tokyo where people get around by foot, bike, or mass transit, many high-rise apartment buildings
  • Dispersed Cities: the city is more spread own because of plentiful land, cheap gasoline, and a network of highway systems
  • Car-Centered Cities: ample land is available for outward expansion resulting in urban sprawl, and passenger vehicles are the main mode of transportation

Motor Vehicles

Advantages

  • Mobility
  • Convenient
  • Economic gain for car industries
  • Helps create urban sprawl

Disadvantages

  • Many deaths from crashes
  • Increased greenhouse gases
  • Increased photochemical smog
  • Congestion

Reducing Automobile Use Is Not Easy, but It Can Be Done

  • Full-cost pricing: high gasoline taxes
  • Difficult to pass in the United States
    • Strong public opposition
    • Mass transit is not an option in most cities
    • Dispersed nature of the U.S.
  • Raise parking fees
  • Tolls on roads, tunnels, and bridges into major cities
  • Car-sharing
  • Charge a fee to drive into a major city
  • It is working in some cities

22.4 How Important Is Urban Land Use Planning?

Conventional Land-Use Planning

  • Land-use planning: To determine the best present and future use of land
    • Encourages future population growth
    • Economic development
    • Revenues: property taxes
    • Environmental and social consequences
  • Zoning
    • parcels of land are designated for specific uses
    • Mixed-use zoning
  • Smart Growth: a way to encourage more environmentally sustainable development; encourages clustered, mixed-use neighborhoods
    • Reduces dependence on cars
    • Controls and directs sprawl
    • Cuts wasteful resource

Smart Growth Tools

Limits and Regulations

  • Limit building permits
  • Urban growth boundaries
  • Greenbelts around cities
  • Public review of new development

Zoning

  • Encourage mixed use of housing and small businesses
  • Concentrate development along mass transportation routes
  • Promote high-density cluster housing developments

Planning

  • Ecological land-use planning
  • Environmental impact analysis
  • Integrated regional planning
  • State and national planning

Protection

  • Preserve existing open space
  • Buy a new open space
  • Buy development rights that prohibit certain types of development on land parcels

Taxes

  • Tax land, not buildings
  • Taxes Tax land on the value of actual use (such as forest and agriculture) instead of on the highest value as developed land

Tax Breaks

  • For owners agreeing not to allow certain types of development (conservation easements)
  • For cleaning up and developing Planning abandoned urban sites (brownfields)

Revitalization and New Growth

  • Revitalize existing towns and cities
  • Build well-planned new towns and villages within cities

Preserving and Using Open Space

  • Urban growth boundary
    • U.S. states: Washington, Oregon, and Tennessee
  • Municipal parks
    • U.S. cities: New York City and San Francisco
  • Greenbelts
    • Canadian cities: Vancouver and Toronto
    • Western European cities

22.5 How Can Cities Become More Sustainable and Livable?

New Urbanism is Growing

  • Conventional housing development
  • Cluster development: High-density housing units are concentrated on one portion of a parcel and the rest of the land is used for commonly shared open space (live, work, play communities)
  • New urbanism, old villageism
    • Walkability: most stores and recreational activities located within 10 minute's walk of homes and apartments
    • Mixed Use and Diversity: provides a mix of pedestrian-friendly shops, offices, and homes to encourage people of all ages and races to move in
    • Quality Urban Design: emphasizes beauty, aesthetics, and architect
    • Environmental Sustainability: based on development and minimal env impact
    • Smart Transportation: well-designed train and bus systems connecting neighborhoods, towns, and cities

The Ecocity Concept: Cities for People Not Cars

Ecocities or green cities

  • Build and redesign for people
  • Use renewable energy resources
  • Recycle and purify water
  • Use energy and matter resources efficiently
  • Prevent pollution and reduce waste
  • Recycle, reuse, and compost municipal waste
  • Protect and support biodiversity
  • Urban gardens; farmer’s markets
  • Zoning and other tools for Sustainability

Science Focus: Urban Indoor Farming

  • Rooftop greenhouses
    • Sun Works→ designs energy-efficient greenhouses
  • Hydroponic gardens
  • Skyscraper farms
  • Ecological advantages and disadvantages

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