Human Impact on the Environment

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Human Impact on the Environment
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Biodiversity

• The variety of different species in an area
• What are some benefits of biodiversity?

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SOME BENEFITS

• Increases stability of the ecosystem by providing
  more food for food webs
• Contributes to the health of the biosphere

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3 types of Biodiversity

• Genetic Diversity the variety of genes or
  inheritable characteristics present in a
  population
• Species Diversity a number of different species
  in the community
• Ecosystem Diversity the variety of ecosystems
  present in the biosphere

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Threats to Biodiversity

• Loss of natural resources minerals, fossil
  fuels, nuclear fuels, plants, animals, soil,
  clean water, clean air, and solar energy
• Human Impact
• Pollution
• Pesticides
• Habitat loss (deforestation)
• Global warming vs. greenhouse effect

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Pollution

• Changes the composition of air, soil, and water.
• Acid precipitation (acid rain) the burning of
  fossil fuels releases sulfur dioxide and nitrogen
  oxides into the atmosphere, forming sulfuric acid
  and nitric acid when combined with water in the
  air.
• Eutrophication fertilizers, sewage, wastes rich
  in nitrogen and phosphorus flow into water,
  causing extensive algae growth.
• Algae uses up the oxygen supply, suffocating the
  other organism in the water

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Pesticides

• Human made chemicals released into envt.
• DDT (dichloro-diphenyl-trichloroethane)
• Used as a pesticide in farms to kill of harmful
  pests
• But later found out DDT
• Is nonbiodegradeable (cannot break down)
• Animals do not lose it from their bodies, it
  stays in there

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Biological Magnification

• Concentration of chemicals increase as you move
  up the food chain or web
• By the time you the top of the food chain or web,
  DDT reached concentration had magnified by
  10,000,000!!

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Habitat Loss

• Deforestation destruction of habitats by
  clearing large areas of land
• In the tropical rainforest, humans are clearing
  areas of tropical rain forests and replacing the
  native plants with agricultural crops or grazing
  land.
• More than half of all species on earth live in
  the tropical rain forest, so what will happen?

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• The reality of deforestation
• http//www1.teachertube.com/viewVideo.php?video_id
  226836titleAmazon_Rainforest_deforestation

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The Greenhouse Effect

• A natural phenomenon where gases reflect heat
  back toward the Earth, keeping it warm
• Caused by an accumulation of greenhouse gases
• (such as CO2)
• CO2 is released by
• burning fossil fuels
• and breathing!

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Effects of Greenhouse Gases

• Greenhouse gases create a NATURAL heat blanket in
  the atmosphere increasing the Earths temperature
• Most people believe this is causing Global
  Warming!
• Can be helped by planting more trees which
  convert CO2 to O2 during photosynthesis

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The Ozone Layer

• Protects us from harmful UV Rays
• Cause of sunburns, eye damage, and cancers
• Made of Ozone Molecules (O3)
• Destroyed by CFCs (chloroflourocarbons)
• Have caused holes and thinning of the ozone

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Global Warming

• An increase in Earths average temperature
  (UNNATURAL EFFECT)
• The Earth is getting warmer, however it
  fluctuates between warm and cool periods
• Do your part to keep the Earth clean and to
  decrease your carbon footprint!

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How do you decrease your carbon footprint?