Land UseLand Use

Land UseLand Use

• 29% of the earth is land– 29% forests and woodlands– 27% range and pastures– 11% cropland– 33% tundra, marsh, desert, urban areas, bare rock,

ice or snow

Forest UseForest Use• More than ½ converted to cropland, pasture,

settlements, and wasteland• Ecological roles:

– Regulating climate, controlling water runoff, providing food and shelter for wildlife, and purifying air.

• Used for:– Fuel, construction materials, paper products

• Approximately 25% of world’s forests are actively managed for wood production.

Forest ManagementForest Management• Harvesting methods

– Selective cutting– Seed tree cutting– Strip cutting– Clear cutting

Urbanization & Urban growthUrbanization & 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.

Urbanization & Urban growthUrbanization & 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).

Urbanization & Urban GrowthUrbanization & Urban Growth• Most of growth in developing countries will

be urban growth with all of its problems– 38% of the people in live in cities. – By 2025 it will be 54%.

• 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

Mexico CityMexico 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

United States UrbanizationUnited 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

Impacts of Urban SprawlImpacts of Urban Sprawl

Fig. 25-8p. 666

Fig. 25-8p. 666

Impacts of Urban SprawlImpacts of Urban Sprawl

Urban Resources & Environmental ProblemsUrban Resources & Environmental Problems• 45% of people living in 5% of land – cities

– consume 75% of the world’s resources

• Urban areas depend upon imports

Major Urban Problems in U.S.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

Drive alone 80%

Other 4%

Public transit 5%

Car pool 11%

Motor vehicle concentrationMotor vehicle concentration• Ground transportation: individual (cars, etc)

and mass (buses and rail)• 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

Benefits of urbanizationBenefits of urbanization

• recycling more economically feasible

• decreased birth rates reduces environmental pressures

• population concentration impacts biodiversity less

Pros and Cons of Mass transitPros 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

Alternatives to Urban Land Use?Alternatives to Urban Land Use?

• Smart Growth-efficient use of land resources and existing urban infrastructure– Using zoning laws to prevent sprawl, direct growth

in certain areas• Make downtown vital and livable

• Alleviate substandard housing

• Solve pollution problems

• Efficient mass transportation

• Provide ample green space

So What Does This Mean?So What Does This Mean?

• We need to plan, plan, and do more planning….

• And that’s what you’ll be doing…..

• Good luck!