Date post: | 28-Mar-2015 |
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Land ResourcesForest ResourcesOcean Resources
Air ResourcesWater ResourcesOzone DepletionGlobal Warming
Human Impact
Land Resources
What is happening? Plowing removes the roots that hold the soil in place,
increasing the rate of Soil erosion SOIL EROSION – is the wearing away of surface soil by
water and wind. Desertification- the process of turning once productive
areas into deserts from a combination of farming, overgrazing, and drought.
Land Resources
Why is it a problem? Soil is a renewable resource, however it can be
permanently damaged if mismanaged
What is being done? Contour plowing- fields are plowed across the slope of the
land to reduce erosion Leaving stems and roots of the previous year’s crops in
place to hold soil
Forest Resources
What is Happening? Deforestation- loss of forest
which leads to severe erosion Why is this a problem?
Old growth forest can be considered a nonrenewable resource because it would take centuries to reproduce
Forests provide O2 and remove CO2 from the atmosphere
They also store nutrients and provide food and habitat to organisms
Forest Resources
What is being Done? Tree farms can be planted
and harvested efficiently making them fully renewable resources
Tree geneticists are also breeding new, faster-growing tree varieties that produce high- quality wood.
Ocean Resources
What is happening? Overfishing- fish stocks in
many fisheries are being harvested faster than they reproduce.
Why is this a problem? People depend on the ocean
as a major source of protein, both from finfish and from shellfish
With the amount of fish caught each year increasing the fish cannot reproduce fast enough to keep up
Ocean Resources
What is being done? Limiting the catch of fish Certain fishing grounds have
been temporarily closed Aquaculture- farming of
aquatic organisms
Air Resources
What is happening? Smog- a mixture of chemicals that occurs as a gray-brown haze
in the atmosphere. This is due primarily to automobile exhausts and industrial emissions
Pollutant- a harmful material that can enter the biosphere through air, land or water The burning of fossil fuels can release pollutants that cause smog and
other problems in the atmosphere.
Air Resources
Why is it a problem? This leads to toxins that enter the mouth, nose and lungs causing
health problems over the long term. Gases released from the burning of fossil fuels combine with water
vapor to form ACID RAIN Acid rain kills plants, and changes the chemistry of soils
What is being done? Technology to control emissions from factory smokestacks Strict automobile emission standards and clean air regulations
Water Resources
What is happening? Pollution such as OIL
SPILLS threatens our water supply
Improperly discarded chemicals can enter streams and rivers
Domestic sewage entering or water ways causing increase in bacteria growth
Water Resources
Biomagnification
Water Resources
Why is this a problem? Fresh water is used daily for everything from drinking and
washing to watering crops and making steel. Although water is a renewable resource, the total supply of
fresh water is limitedWhat is being done?
Conservation by: drip irrigation, and consumer awareness of conservation
Ozone Depletion
What is happening? Chemicals called CFC’s
which were once widely used in aerosol cans, the production of plastics and as coolants in freezers, refrigerators and air conditioners have caused a hole in our ozone layer and this hole is continuing to grow
Ozone Depletion
Why is this a problem? The ozone layer absorbs a
great deal of harmful UV rays before it reaches the earth’s surface .
As the ozone layer is depleted UV exposure can cause sunburns, cancer, eye damage and decrease an organism’s resistance to disease
What is being done? The US has joined many
other nations to phase out the use of CFCs
Global Warming
What is happening? An increase in the average temperature of the biosphere. Over the past 120 years global temperatures have risen .5
degrees Celsius CO2 and other gases are being released into the
atmosphere and being retained causing more heat.
Global Warming
Why is this a problem? Polar ice caps will continue to melt
and could rise enough to flood some low lying coastal areas
Storms and other weather disturbances could become more frequent and severe
Heat favors rodents weeds and insect that reproduce and spread quickly
What is being Done? Alternate energy sources
are being researched to reduce or stop the burning of fossil fuels that release gases into the atmosphere that retain heat.