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Natural Resources

Natural Resources

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Natural Resources

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  1. Natural Resources

  2. Natural Resources • Natural resources: substances that come from Earth EXAMPLES • Metals (gold, copper, iron ore, aluminum) for jewelry, coins, wiring, construction, aircrafts • Nonmetals (halite, graphite, garnet, feldspar) for food, pencil lead, jewelry, glass • Fossil Fuels (coal, petroleum) for heating, power plants, fuels, medicines, plastics

  3. Scarcity As the need for resources grow, some resources may be hard to find. Scarcity causes the prices of resources to increase or it may push us to find other substances to meet our needs

  4. Recycling Recycling is a way to meet our needs and save resources Recycling reduces the amount of trash that must be disposed of

  5. Renewable Resources Renewable resources: can be replaced after they have been used Examples: trees and, in general, freshwater (excludes desert areas)

  6. Nonrenewable Resources Nonrenewable resources: after they are used, they cannot be replenished for millions of years if at all In some cases, resources are forming in some locations, but at a pace much slower than the rate they are being used Examples: gold and copper, iron, aluminum, and fossil fuels

  7. Fossil Fuels Fossil Fuels: coal, oil and natural gas, which were formed millions of years ago from the remains of ancient organisms Scientists estimate that we will run out of coal within 200 years Petroleum, a fossil fuel, is used for medicines, plastics, detergents and fertilizers

  8. Alternative Energy Sources Alternative Energy Sources: other sources of energy to replace fossil fuels Solar energy is plentiful and can provide heat, hot water and generate electricity Problem: amount of sun varies with the time of day and seasons. It is also more expensive than fossil fuels

  9. Alternative Energy Sources Geothermal energy: comes from heat within Earth that can be used to generate electricity and produce heat and hot water Problems: it’s only available in certain areas such as northern California and Iceland

  10. Alternative Energy Sources Wind-driven generators: used for electricity Problem: only practical in areas where there are strong, steady winds.

  11. Alternative Energy Sources Hydroelectric power Problems: large areas are flooded when dams are built to hold back a river and generate electricity

  12. Nuclear Energy Nuclear energy is used to generate electricity without causing air pollution Drawback: it is extremely dangerous and there is a need for long-term storage of radioactive wastes. Terrorists might also target nuclear plants or use radioactive materials