Objective: How have humans negatively impacted the environment?

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• Objective How have humans negatively impacted
  the environment?
• Do Now What is thispicture depicting?

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Do Now Tuesday 9/24

• Take out Ecology Notes
• Take paper from front
• Homework Biome book due Wed.

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What is the function of this greenhouse?
Sunlight passes through the glass, where the
interior absorbs the radiant energy changing it
to heat, the glass stops the heat from escaping
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Greenhouse gases

• Greenhouse gases trap and absorb the infrared
  radiation
• Keep Earth warm
• Gases sulfur dioxides, nitrogen dioxides, carbon
  dioxide
• Contribute to pollution smog, acid rain, air
  pollution

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The Greenhouse Effect
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The Greenhouse Effect

• Greenhouse gases blanket the Earth and keep it 33
  degrees Celsius warmer than without the gases
• This is essential to life on Earth..otherwise we
  would be colder

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Global Warming

• Global warming is caused when carbon dioxide from
  the burning of fossil fuels adds too many
  greenhouse gases, resulting in increases in the
  Earths temperature and melting of polar ice caps

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What is this graph showing?
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(No Transcript)
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Global Warming

• As the temperature of oceans rises, so will the
  probability of more frequent hurricanes

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Global Warming

• Increased probability and intensity of droughts
  and heat waves

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Global Warming

• Melting of the polar ice caps can raise sea
  levels
• Puts more freshwater into the ocean
• Can cause endangerment of animals

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How does Global Warming differ from the
Greenhouse Effect?

• Global warming is the warming of the earth as a
  result of the greenhouse effect.

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The Ozone Layer

• The ozone layer a layer of gases that absorbs
  radiation from the sun
• Ozone absorbs UV rays and protects us

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Ozone Depletion

• The ozone gets depleted (gets holes in it) when
  cleaners, air conditioners and refrigerators are
  used and release chemicals called
  chlorofluorocarbons (CFCs) into the atmosphere.

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So What?

• - Without ozone, more UV rays hit earth
• - Holes in the ozone can lead to higher rates of
  skin cancer.

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Endangered

• Endangered animals are still living today but are
  in immediate danger of extinction.

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Extinction

• Species that are gone forever

Stellar Sea Cows were hunted to extinction by
people. They were enormous sea mammals that could
be 20 to 30 feet long and weighed about 8,500
pounds. Stellar Sea Cows were killed for
food. RED LIST
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BIOGEOCHEMICAL CYCLES

• Chemicals cycle through an ecosystem
• Producers make organic compounds like glucose
  from CO2, H2O, and sunlight.
• Consumers eat the producers, incorporating some
  of those organic compounds into their own bodies
• Decomposers break down dead
  organisms, returning the
  chemicals to the ecosystem

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CARBON CYCLE

• Carbon in the air is in the form of CO2
• CO2 is also found dissolved in waters of the
  earth
• Plants take in CO2 for photosynthesis
• Plants incorporate the Carbon from CO2 into
  organic substances (ex carbohydrates) called
  carbon fixation
• Animals eat carbs which are used for cellular
  respiration and CO2 is released back into
  atmosphere

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• Carbon exists in the nonliving environment as
• carbon dioxide (CO2) in the atmosphere and
  dissolved in water
• carbonate rocks
• deposits of coal, petroleum, and natural gas
  derived from once-living things
• dead organic matter
• Carbon enters the biotic world through the action
  of autotrophs
• Primarily photoautotrophs, like plants and algae,
  that use the energy of light to convert carbon
  dioxide to organic matter.
• Carbon returns to the atmosphere and water by
• respiration (as CO2)
• Burning
• decay (producing CO2 if oxygen is present,
  methane (CH4) if it is not.

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WATER CYCLE

• The earth has a limited amount of water.  That
  water keeps going around and around and around
  and around.
• This is what we call the "Water Cycle".
• This cycle is made up of a few main parts
• Evaporation (and Transpiration)
• Condensation
• Precipitation
• Collection

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• Human impact

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NITROGEN CYCLE

• All life requires nitrogen-compounds,
• examples proteins and DNA
• Air, which is 79 nitrogen gas (N2), is the major
  reservoir of nitrogen.
• But most organisms cannot use nitrogen in this
  form.
• Plants must secure their nitrogen in "fixed" form
• examples incorporated in compounds such as
  ammonia
• Animals get their nitrogen from plants (or
  animals that have fed on plants).

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• Four processes participate in the cycling of
  nitrogen through the biosphere
• Nitrogen fixation- bacteria in soil convert
  atmospheric nitrogen into ammonium (NH4) and
  nitrate (NO3-)
• Decay-the proteins made by plants enter and pass
  through food webs just as carbohydrates, nitrogen
  compounds are excreted and then decay
• Nitrification-other bacteria in soil convert
  ammonium to nitrates which producers use to make
  protein
• Denitrification-nitrates to nitrogen gas, thus
  replenishing the atmosphere.

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• Human impact