Environmental Science Ch' 8: Land

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Environmental Science Ch. 8Land
2
California Content Standards for Science
Addressed

• Earth Science
• 9 The geology of California underlies the state's
  wealth of natural resources as well as its
  natural hazards. As a basis for understanding
  this concept
• 9(a)Students know the resources of major economic
  importance in California and their relation to
  California's geology.
• Life Science
• 6(b)Students know how to analyze changes in an
  ecosystem resulting from changes in climate,
  human activity, introduction of nonnative
  species, or changes in population size.

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Ch 8-1Why Do I Need To Know This?

• Because we all use land every day for places to
  live and to provide the food, minerals, materials
  and resources that we need.
• Because almost all of southern California is
  already an urban center with many of the problems
  associated with urban centers.
• Because over the next 20 years, the population of
  California is expected to grow by another
  10,000,000 people, which will cause an even
  greater urban crisis here!

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Ch. 8-1 The City

• Key Terms
• Infrastructure
• Land-use Plan
• Suburban Sprawl
• Urbanization

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Key Sections Ch. 8-1

• The City
• The Urban-Rural Connection
• Urbanization
• The Urban Crisis
• Suburban Sprawl
• Land-Use Planning
• Mass Transportation
• Inner-City Renovation
• Open Spaces

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The City

• Between 1984 and 1992, over 210,000 acres of
  productive farmland were converted into towns and
  cities in California!
• In Orange County, over 100,000 acres were lost to
  homes and businesses in just the last 15 years!
• This trend is not just limited to Californiaits
  happening world-wide.

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The Urban-Rural Connection

• According to the U.S. Census Bureau, any area
  that has over 5,000 people living in a square
  mile is an urban area.
• About 80 of all Americans live in an urban area.
• By the year 2025, about 66.66 of all the worlds
  people will live in an urban center.
• All of these people need to get their food and
  resources from someplace.
• Consequently, it takes a lot more land to support
  life in the city than just the land in the city.
  So it is very important for people living in
  urban areas to take care of and maintain
  non-urban areas.

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The Urban-Rural Connection-Land Use in the United
States
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Urbanization

• Urbanization happened rapidly in most countries
  starting in the 1850s.
• Urbanization happened as a result of
• Improvements in farming techniques
• Improvements in technology (specifically the
  Industrial Revolution)
• Improvements in Health Care.

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The Urban Crisis

• The rapid rise of cities has created a world-wide
  problem called the urban crisis.
• The urban crisis has to do with the fact that the
  cities have more people living in them than the
  infrastructure can support.
• This overpopulation has led to mass unemployment,
  mass homelessness, and massive health problems.
• It is presently estimated that by 2020 over 25
  of the worlds population will be homeless.

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The Urban CrisisWorlds Population Density Map
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The Urban CrisisThe Worlds Urban Population Map
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Suburban Sprawl

• Suburban sprawl is characterized by unplanned and
  uncontrolled development consisting primarily of
  houses and strip malls surrounding large cities.
  Think of the 909.
• Suburban sprawl is a major problem in developed
  countries such as the United States.
• Every year over 2.5 million acres of land are
  lost to suburban sprawl in the United States.
• Southern California leads the nation in suburban
  sprawl.

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Land-Use Planning

• Land-use planning is a way to combat urban
  sprawl.
• Land-use plans are developed by all cities and
  counties and determine what types of buildings
  can be built in certain areas.
• They may also determine when certain areas will
  be developed.
• A city and county must make allowances for all
  types of legal uses for land in its land use
  plan.
• This ensures that the city/county has the
  necessary infrastructure in place prior to
  support the needs of the community.

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Mass Transportation

• The average American spends over 2500 on
  gasoline and car maintenance just to get to and
  from work while the average European person
  spends half that amount.
• Mass transportation is an efficient and
  environmentally friendly way to get to and from
  work.
• However, in many parts of the U.S., the
  population is not dense enough to support mass
  transportation, and the costs to build mass
  transportation are extremely high.

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Inner-City Renewal

• Over time, the oldest parts of the city tend to
  lose businesses as people leave for the suburbs.
  
• This creates urban decay, in which neighborhoods
  no longer have the jobs and tax base to support
  the area.
• Many cities have engaged in projects to redevelop
  the inner-cities to attract businesses back into
  the oldest parts of the city.
• Some examples include Old Town Orange, Downtown
  Disney, Old Town Fullerton, Old Town Tustin, etc.

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Open Spaces

• One important aspect to land-use planning is the
  setting aside of land for open spaces.
• Open spaces come in many forms such as parks,
  pools, hiking/biking trails, gardens, etc.
• Open spaces can ease problems in cities, and can
  be used for concerts, hiking, biking, etc.
• Open spaces help reduce the drainage problems for
  cities during rain and allow for native plants
  and animals to have habitats. They also help
  migratory animals.
• Open spaces help the environment by absorbing
  carbon dioxide, filtering out pollutants,
  producing oxygen and helping to cool down the
  climate in the cities.

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Ch. 8-2 How We Use Land

• Key Terms
• Clear Cutting
• Desertification
• Mineral Resources
• Overgrazing
• Reclamation

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California Content Standards for Science
Addressed

• Earth Science
• 9 The geology of California underlies the state's
  wealth of natural resources as well as its
  natural hazards. As a basis for understanding
  this concept
• 9(a)Students know the resources of major economic
  importance in California and their relation to
  California's geology.
• Life Science
• 6(b)Students know how to analyze changes in an
  ecosystem resulting from changes in climate,
  human activity, introduction of nonnative
  species, or changes in population size.

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Ch. 8-2Why Do I Need To Know This?

• Because mining and ranching are two of the most
  important and largest industries in California
  and the United States.
• Because we rely on mining and ranching to supply
  the food we eat and the raw materials we need for
  everything that we use.
• Because if we dont manage our resources wisely,
  we will run end up destroying them or running out
  of them.

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Key Sections Ch. 8-2

• How We Use Land
• Harvesting Trees
• Deforestation
• Reforestation
• Protecting Forests
• Ranching
• Problems on the Range
• Maintaining the Range
• Mining
• The Effects of Mining
• Responsible Mining

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How We Use Land

• Only about 2 of all the land in the U.S. is used
  for cities. That means about 98 of all the land
  is non-urban and used for
• Farming/Ranching
• Forests
• Mining
• Open Spaces
• If we are not careful, we can overuse our
  non-urban lands, making them inefficient or
  depleted.

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Harvesting Trees

• Trees are the major source of heating and cooking
  around the world.
• The average person uses about 1800 cm3 of wood a
  day
• The average American uses about 3.5 times that
  amount. Thats equivalent to each American using
  a 100 ft. tall tree each year!
• Fuelwood isnt the only use for forests. In
  developing countries many forests are cleared to
  make way for farming and ranching operations.

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Deforestation

• As a result of all the logging and removal of
  trees, over 5 million acres of forest land are
  lost around the world each year!
• Thats almost 570 acres an hour of forest being
  lost!
• The 2 main ways of logging are
• Clear-cutting
• Selective cutting
• Clear-cutting is the removal of all the trees in
  an area for logging purposes
• Selective cutting is the removal of only certain
  trees to allow an ecosystem to continue after the
  logging is done.
• In the U.S. most states require loggers to only
  use selective cutting.
• Both clear-cutting and selective cutting have
  advantages and disadvantages.

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Harvesting Trees
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Reforestation

• Reforestation is the planting of new trees to
  replace those trees taken by loggers.
• This is still a slow process that can take
  between 20 to 50 years for the area to recover.
• When loggers use clear-cutting methods, this is
  the only way for an area to recover.
• Many governments require logging companies to
  plant new trees after they are done logging an
  area.
• The U.S. requires reforestation on all publicly
  owned lands.
• However, over 90 of all wood in the world comes
  from areas that does not require reforestation!

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Protecting Forests

• Most state governments are working to protect
  forests.
• In California there have been many efforts to
  save the redwood forests in Northern California.
• There have been many bond initiatives to buy land
  for the state to protect forests as well.
• Additionally, many charities and non-profit
  groups are buying up forest land to prevent them
  from being used for logging.

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Ranching

• Ranching provides us many of the supplies that we
  need daily.
• Ranchers use the grasses and shrubs on the
  rangeland to graze their animals.
• It is estimated that worldwide, we will need a
  40 increase in production from ranching by 2030!

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Problems on the Range

• Grasses and shrubs have many unique features that
  make them able to survive droughts, fires, frost
  and grazing.
• Grasses and shrubs have thick and fibrous roots
  that hold the soil on the ranges together.
• When an area is overgrazed, the plants die and
  the roots no longer hold the soil together.
• The topsoil then erodes very quickly, and the
  area no longer can grow anything at all.
• This process is called desertification.

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Problems on the Range
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Maintaining the Range

• In the U.S. many efforts have been made to try
  and save the rangelands.
• Laws have been passed to limit the sizes of herds
  to an amount the range can safely accommodate.
• Laws have also been passed to move herds in ways
  that limit their impact on the environment.
• Finally, efforts have been made to try and remove
  the exotic plants that have invaded and destroyed
  the ranges.

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Mining

• More dirt is moved every year in mining than is
  moved by all the rivers in the world.
• Mining seeks to find minerals, which are pure
  substances (either a pure element or a pure
  compound) that has beneficial uses.
• Industry then uses the minerals to produce almost
  everything that we use today.
• The two most common forms of mining are
• Open-pit mining
• Strip Mining

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The Effects of Mining

• If you connected all the strip mines and open-pit
  mines in the U.S. together, youd make a hole a
  mile wide, a mile deep and it would stretch
  across the U.S.
• Mines are some of the biggest point sources for
  pollution in the country because the mineral
  bearing rocks often have very harmful substances
  in them, such as sulfur.
• Most rocks only contain small amounts of useful
  minerals, so for every ton of the mineral
  produced, the mine can produce hundreds or
  thousands of tons of waste and pollution!

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Responsible Mining

• In the U.S., laws have been passed requiring
  mining companies to reclaim the land.
• To reclaim land, miners remove the topsoil from
  the land they want to mine and set it aside.
• When the miners are done, they fill the strip or
  pit in and replace the topsoil, plant new trees,
  and restore the land as best they can to its
  pre-mining condition.
• However, the 2 best way to reduce the harmful
  effects from mining is to use fewer resources and
  to recycle as much as possible so that we do not
  need to mine as much in the future!

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Ch. 8-3 Public Land In the United States

• Key Terms
• Wilderness

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California Content Standards for Science
Addressed

• Earth Science
• 9 The geology of California underlies the state's
  wealth of natural resources as well as its
  natural hazards. As a basis for understanding
  this concept
• 9(a)Students know the resources of major economic
  importance in California and their relation to
  California's geology.
• Life Science
• 6(b)Students know how to analyze changes in an
  ecosystem resulting from changes in climate,
  human activity, introduction of nonnative
  species, or changes in population size.

37
Ch 8-3Why Do I Need To Know This?

• Because you are a part owner of over 40 of the
  land in the U.S. and may wish to use them
  someday.
• Because every year there are ballot initiatives
  to buy more land to be owned by the public.
• Because publicly owned lands play a very
  important part in maintaining our nations
  environment.

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Key Sections Ch. 8-3

• Public Land in the United States
• This Land Belongs To You and Me
• Managing Our Public Lands
• Wilderness
• Troubled Lands
• People Control in Wilderness Areas

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Public Lands in the United States

• In 1870, Congress set aside over 2 million acres
  to create Yellowstone National Park.
• Yellowstone was the first National Park in the
  world.
• The land in a National Park is permanently set
  aside and may not be used for any development.
• Today there are over 55 National Parks and over
  320 National Monuments in the United States!

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Public Lands in the United States
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This Land Belongs To You and Me

• Approximately 40 of all the land in the United
  States is owned by the public.
• The federal government is the largest land owner
  in the country!
• The states also own much of the land as well.
• Often this land is leased out for agricultural
  uses.
• However, it is possible to go on most publicly
  owned lands for camping and hiking purposes.

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Managing Our Public Lands

• There are many federal and state agencies that
  manage and oversee public lands in the U.S. They
  include
• The National Park Service
• The U.S. Fish and Wildlife Service
• The Bureau of Land Management
• The U.S. Forest Service
• The Bureau of Indian Affairs
• The Military
• Some areas are controlled by multiple government
  agencies which creates problems as different
  groups have different ideas on how to best use
  and manage the land.

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Wilderness

• According to the Wilderness Act of 1964 a
  wilderness is an area in which the land and its
  ecosystem are protected from development.
• Wilderness areas play important roles to
  maintaining the overall environment in the U.S.
• So far there are 657 wilderness areas in the U.S.
  covering 104 million acres.
• In a wilderness people can go
• Hiking
• Fishing
• Boating
• Camping

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Troubled Lands

• As our population grows, more people are going
  into the public lands, causing environmental
  damage.
• Additionally, nearby developments from cities has
  caused additional environmental stresses and
  pollution.
• Finally, pre-existing mining and ranching claims
  are still allowed to be used, although, new
  claims cannot be made.

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People Control in Wilderness Areas

• As a result of all the human impacts on human
  areas, some restrictions have been placed on the
  amount of people or the types of uses for the
  land.
• Always be sure to check with a park ranger or
  with a government agency before going onto public
  land.