Impacts of Urbanization

Urbanization * Creation and growth of urban areas or cities and their surrounding developed land * Urban growth * The rate of increase of urban populations * Urban areas grow in two ways * Natural increase * Immigration * Rural people are pulled to urban areas in search of jobs, housing, educational opportunities, health care, entertainment, and freedom from religious, racial, and political conflicts * Main advantages * Access to education * Sanitation * Access to health care * More jobs * Better transportation * Main disadvantages * Worse air quality * High population density * Increase spread of communicable disease * Noise pollution * High levels of stress * High crime rate
Advantages of Urbanization * Cities * Centers of economic development, innovation, education, industry, commerce, transportation, and jobs * Better access to medical care, family planning, education, and social services * Recycling is more economically feasible because concentrations of recyclable materials * Concentrating people in cities helps preserve biodiversity by reducing the stress of wildlife habitats * Central cities can save energy if residents rely more on energy-efficient mass transportation
Disadvantages of Urbanization * Huge ecological footprints * Lack of vegetation * Water problems * Concentrate air pollution * Health issues * Excessive noise * Create different climates * Light pollution
Phases of Urbanization * People migrated from rural ares to large central cities * Many people migrated from large central cities to suburbs and smaller cities * Some people fled both cities and suburbs and migrated to developed rural areas
Urban Sprawl * The growth of low-density development on the edges of cities and towns * Major factors that promoted urban sprawl in the U.S. * Ample land was available for most cities to spread outward * Federal government loan guarantees for new single family homes for WWII veterans stimulated the development of suburbs starting around 1950 * Low cost gasoline and federal and state funding of highways encourages automobile use and the development of outlying tracts of land * Technology has made possible to work from home * Goof suburban school districts * More space to raise children * Higher quality of life
Environmental Problems * Building homes in preserved areas causes habitat destruction/fragmentation * Problems related to the high usage of fossil fuels, since more people drive to work and other places
Ecological Footprints * Urban populations only occupy around 2% of the earth’s land are, but they consume 75% of its resources and produce 75% of all carbon dioxide emissions from human activities * Most of the world’s cities are not self-sustaining systems * Large areas of land must be destroyed and degrade to provide for the urban people, which results in the lowering of biodiversity * Most urban dwellers live in an artificial environment that isolates themselves from natural areas that contain biodiversity
Lack of Vegetation * Most trees, shrubs, and other plants are destroyed in urban areas in order to make way for development * Vegetation is important because it absorbs air pollutants, gives off oxygen, cools the air through transpiration, provides shade, muffles noise, and provides habitats
Water Pollution * As water demands increase, expensive reservoirs must be built, and deeper wells must be drilled * Can deprive rural and wild ares of surface water and deplete groundwater * Covering land with asphalt and concrete causes precipitation to runoff quickly and overload storm drains, causing flooding * Global warming is causing urban dwellers in arid areas to have a shortage of water
Pollution * High population densities and high resource consumption causes cities to produce most of the world’s air pollution, water pollution, and waste * Pollution is produces in a small area and cannot be dispersed and diluted as easily as pollution in rural areas * Most of the CO2 from human related sources are due to urban areas * Nitrogen nutrients in runoff can disrupt the nitrogen cycle
Excessive Noise * Urban dwellers are subject to noise pollution * Any unwanted, disturbing, or harmful sound that impairs or interferes with hearing, causes stress, hampers concentration and work efficiency, or causes accidents * Too much noise can kill someone and cause permanent hearing damage
Light Pollution * The artificial light created * Affects some plant and animal species * Migrating birds * Lured off course by the lights of a high rise building * Fatally collide with the buildings
Heat Island Effect * Cities are generally warmer than the suburbs and rural areas * Causes * The enormous amount of heat created by cars, factories, air conditioners, and heat-absorbing dark roofs and streets in cities creates an urban heat island, surrounded by cooler rural and suburban areas * Consequences of the heat island effect * Increases the formation of photochemical smog * Increases dependence on air conditioning for cooling * Increases energy consumption
Transportation * Motor vehicles have many harmful effects on people and the environment * Automobile accidents kill approximately 1.2 million people a year and injure another 15 million * Kill about 50 million wild animals and family pets a year * World’s largest source of outdoor pollution, and cause 30,000 to 60,000 premature deaths per year in the U.S. * Fastest growing source of climate changing CO2 emissions * Account for ⅔ of oil used in the form of gasoline in the U.S. and ⅓ of the world * At least a third of urban land worldwide, and half in the U.S. is devoted to roads, parking lots, gasoline stations, and other automobile related uses
Reducing Automobile Use * Charge a tax on gasoline to cover the estimated harmful cost of driving * Such a tax would amount to about $3.18 per liter of gasoline in the U.S.
Alternatives to Car Ownership * Mass transit rail * Advantages * Uses less energy * Produces less air pollution * Requires less land * Causes fewer injuries and deaths * Reduces car congestion in cities * Disadvantages * Expensive * Commits riders to a schedule * Causes noise and vibration * Bicycles * Advantages * Affordable * No pollution * Quiet * Require little parking space * Easy to maneuver in traffic * Require few resources * Disadvantages * Little protection in an accident * No protection from bad weather * Impractical for long trips * Tiring * Lack of secure parking * Buses * Advantages * Can be rerouted * Cost less to develop and maintain * Can reduce car use and air pollution * Disadvantages * Can lose money due to low fares * Can get caught in traffic and add to pollution * Commits riders to a schedule * Noisy * Rapid Rail * Advantages * Reduce travel by car and plane * Ideal for long trips * Energy efficient * Disadvantages * Expensive * Must operate along heavily used routes * Cause noise and vibration
Conventional Land-Use Planning * Urban and rural areas use some form of land-use planning to determine the best present and future use of each parcel of land * Encourage future population growth and economic development, regardless of the environmental and social consequences * Leads poorly controlled urban growth and sprawl * 90% of the revenue of local governments used to provide public services comes from property taxes levied on building/property based on economic value * Zoning * Most widely used approach in which various parcels of land are designated for certain uses * Can be used to control growth and protect areas from some types of development * Disadvantages * Threatens/destroys environment * Favors high-priced housing over protecting environmentally sensitive areas and low-priced housing because of property tax revenue from high-priced developments
Smart Growth * 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 clutter housing developments * Planning * Ecological land use planning * Environmental impact analysis * Integrated regional planning * State and national planning * Protection * Preserve existing open space * Buy new open space * Buy development rights that prohibit certain types of development on land parcels * Taxes * Tax land, not buildings * Tax land on value of use * Tax breaks * For owners not agreeing to allow certain types of developments * For cleaning up and developing abandoned urban sites * Revitalization and New Growth * Revitalize existing cities/towns * Build well-planned new towns and villages within cities