Human Impacts on Ecosystems

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Human Impacts on Ecosystems

• Topic 2
• Unit 1
• Science 7

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• Humans affect the environment around them as they
  meet their needs.

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• Calgary then and now

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• To meet our basic needs we rely on the ecosystem
  around us, just as all living things do.
• We use natural resources (the materials and
  products that are found in nature) to meet our
  basic needs.

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Examples of natural resources

• Trees
• Water
• Oil
• Minerals

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Canadas Natural Resources

• Video (317)

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• Human impacts can be large or small
• If one person drives a car the impact is not that
  great, but when millions of people drive cars the
  impact is large.
• Our impact on the environment has changed over
  time as the human population has increased and
  our technology has advanced

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Wants vs Needs

• A need is something you require for survival
• A want is something you can live without, but it
  makes your life more enjoyable.
• EX food is a need, but having food from distant
  locations available year-round is a luxury.

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