1 / 26

Sustainable Cities: Urban Land Use and Management

Sustainable Cities: Urban Land Use and Management. Chapter 26 Miller 11th Edition. Definitions. Urban (metropolitan) area = town plus its suburbs City = large number of people with a variety of professions who depend on resources from the outside of city boundary

vaughn
Télécharger la présentation

Sustainable Cities: Urban Land Use and Management

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Sustainable Cities: Urban Land Use and Management Chapter 26Miller 11th Edition

  2. Definitions • Urban (metropolitan) area = town plus its suburbs • City = large number of people with a variety of professions who depend on resources from the outside of city boundary • Rural area = an area with a population less than 2,500 people • Village = group of rural households liked by custom, culture,family ties. Historical utilization of natural resources

  3. Urbanization & Urban growth • Degree of urbanization is percentage of population living in area of greater than 2,500 people • Urban growth due to: • natural increase - births • immigration - poor are pulled to urban areas or are pushed from rural areas • Trends of urban growth: • Increase of 2% to 45% of people in urban areas since 1950 • By 2050 about 66% of the world’s people will be living in urban areas.

  4. Urbanization & Urban growth • The number of large cities is mushrooming • megacities and megalopolis • Today, more than 400 cities have over 1 mil. or more people. 19 megacities with over 10 mil. People i.e.Tokyo (28 mil), Mexico City (18 mil), New York (17 mil). • Most of growth in developing countries will be urban growth with all of its problems • 38% of the people in live in cities. But by 2025 it will be 54%. Many of these cities are already short on water, have waste & pollution problems.

  5. Urbanization & Urban Growth • Urban growth is slower in developed countries • 75% of the people live in cities. But by 2025 it will be 82%. • Poverty is becoming increasingly urbanized • slums, squatter settlements and shantytowns • at least 1 billion people live in crowed slums of inner cities. No access to water, sewer, electricity, education etc. 100 mil people are homeless & sleep on the streets • Case study - Mexico City

  6. Mexico City • The world’s second largest city with 18 million people or one in five Mexicans • severe air pollution (over 4 million cars) within a valley that causes an estimated 100,000 premature deaths/year • high unemployment rate, close to 50% • high crime rate • over one-third (6 million) of its residents live in slums (barrios) without running water, sewer (but running sewage), or electricity • high infection rates i.e. salmonella, hepatitis

  7. United States Urbanization • Migration to large central cities • Migration from cities to suburbs • Migration from north & east to south & west • Urban sprawl, growth of low-density development on the edge of cities. Encouraged by: - availability of cheap land, (forests, agriculture fields etc.). - government loans guarantees for new single-family homes - government & state funding of highways - low-cost gasoline encourage car use - low interest mortgage

  8. Major Spatial Patterns • Concentric Circle City such as New York • Sector City is the large urban area extending from San Frdancisco to San Jose, CA • Multiple Nuclei City is Los Angeles • Megalopolis is when separate cities join such as the Bowash

  9. Concentric Circle Model • Central business district (CBD) • Deteriorating transition zone • Worker’s homes • Middle-class suburbs • Commuter's zone

  10. Sector Model • High-rent residential • Intermediate-rent residential • Low-rent residential • Education and recreation • Transportation • Industrial • Core (CBD)

  11. Multiple-Nuclei Model • CBD • Wholesale, light manufacturing • Low-rent residential • Intermediate-rent residential • High-rent residential • Heavy manufacturing • Outlying business district • Residential Suburb • Industrial Suburb

  12. Major Urban Problems in U.S. • Deteriorating services • Aging infrastructures • Budget crunches from lost tax revenues as businesses and affluent people leave • Rising poverty with violence, drugs, decay • Urban sprawl - growth of low-density development on edges of cities and towns • 9 consequences of “bad growth”

  13. 75% of the US population live in urban areas occupying 3% of the country’s land area

  14. Urban Resources & Environmental Problems • 45% of people living in 5% of land – cities – consume 75% of the world’s resources • Urban areas depend upon imports • Benefits of urbanization: • recycling more economically feasible • decreased birth rates reduces environmental pressures • per capita expenditures on environmental protection high in urban areas • population concentration impacts biodiversity less

  15. Urban Resource and Environmental Problems • Destruction of plant life - what is $ value? • Cities produce little of own food • Urban heat island effect --> dust dome • 5 ways to counteract this effect • Water supply and flooding problems • 5 ways to reduce demand on reservoirs and waste treatment systems • High pollution exposure

  16. The enormous amount of heat generated creates an urban heat island • Additional heat changes climate of surrounding area

  17. Urban Resource & Environmental Problems • Excessive noise exposure  health effects • Hearing loss, hypertension, muscle tension, migraines, headaches, higher cholesterol levels, gastric ulcers, irritability, insomnia, psychological disorders, aggression

  18. Urban Resource & Environmental Problems • Beneficial effects: • education • social services • medical care • Harmful effects • infectious disease spread • high density population • inadequate drinking and sewage system • physical injuries • pollution exposure • Urban Sprawl

  19. Impacts of Urban Sprawl Water Land and Biodiversity Human Health and Aesthetics Increased runoff Increased surface water & groundwater pollution Increased use of surface water & groundwater Decreased storage of Surface water & groundwater Increased flooding Decreased natural Sewage treatment Loss of cropland Loss of forests & grasslands Loss of wetlands Loss & fragmentation of wildlife habitats Increased wildlife road kill Increased soil erosion Contaminated drinking water & air Noise pollution Sky illumination at night Traffic congestion

  20. Impacts of Urban Sprawl Energy, Air, and Climate Increased energy use and waste Increased air pollution Increased greenhouse gas Emissions Enhanced global warming Warmer microclimate (heat island effect) Economic Effects Higher taxes Decline of downtown business districts Increased unemployment in central city Loss of tax base in central city

  21. Transportation and Urban Development • Determines where people live, where they go to work and buy stuff, how much land is paved and exposure to air pollution • Cities grow up if they can’t grow out; more prone to use mass transit • Urban sprawl due to cheap gas and land and highways; dispersed car-centered cities use 10x more energy

  22. Drive alone 80% Other 4% Public transit 5% Car pool 11% Motor vehicle concentration • Ground transportation: individual (cars, etc) and mass (buses and rail) • U.S. has 35% of cars and trucks used for 98% of all urban transportation • Motor scooters - effort to change to electric • Riding bicycles; less pollution and dangerous and more efficient than walking • bicycles available for public use • bike and ride systems

  23. Pros and Cons of Mass transit • 3% mass transit use in U.S. to 47% in Japan • 20% gasoline tax revenues to mass transit • Rapid rail, suburban trains and trolley - efficient at high population density • High speed rail lines – replace planes, buses and private cars; but require large government subsidies • Bus systems more flexible than rail systems but efficient when full

More Related