Biogeochemical Cycles

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Biogeochemical Cycles

• Miss Holl
• Rowland High School
• January 29, 2007

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Recall Question

• List the Earth System Cycles we have discussed in
  Earth Science class thus far.
• What are some other cycles you can think of?
  Write them down.

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Components of the Earth System

• In general, we can subdivide the Earth system
  into
• atmosphere
• hydrosphere
• lithosphere
• biosphere

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Law of Conservation of Matter

• All matter cycles It is neither created nor
  destroyed.
• As the Earth is essentially a closed system with
  respect to matter, we can say that all matter on
  Earth cycles.
• Matter (in this case) is defined as elements
  (carbon, nitrogen, oxygen) or molecules (water).

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What is a Biogeochemical Cycle?

• Biogeochemical cycles describe the movement (or
  cycling) of matter through a system.

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What is a Biogeochemical Cycle?

• Biogeochemical cycles are LINK the components of
  the Earth System!!

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Biogeochemical Cycles

• Carbon Cycle
• Oxygen Cycle
• Nitrogen Cycle
• Phosphorous Cycle
• Water Cycle

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Carbon Cycle

• In the global carbon cycle, different forms of
  carbon move among reservoirs at different rates.
• Carbon is stored in RESERVOIRS.
• CARBON RESERVOIRS are the atmosphere, oceans,
  biomass (dead and living plants and animals), and
  fossil fuels.

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Carbon Cycle
respiration

• Photosynthesis moves carbon from atmosphere to
  the biosphere.
• Carbon is released back into the atmosphere
  through respiration.

photosynthesis
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The Global Carbon Cycle

• carbon cycle

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Carbon cycle
carbon cycle
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Nitrogen Cycle

• Nitrogen must be fixed by bacteria because it
  is not in a form that is usable by plants and
  animals.

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global nitrogen cycle
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Box Model
nitrogen cycle
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Extend your thinking

• Which biogeochemical cycles might exist on other
  planets?
• If the Earth System has four major components,
  how many does Mars have? What would they be
  called?

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We have learned

• Matter on Earth moves among reservoirs, which
  exist in each of the four components of the Earth
  System.

Biogeochemical cycles...
describe this movement of matter.
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Homework

• Bring in a piece of the carbon cycle!
• In one paragraph, describe how your piece fits
  into the big picture of the carbon cycle.
• How does it release carbon?
• How does it store carbon?
• Color your carbon cycle handout.
• NOW --
• Glue the Carbon Cycle Handout in your I.A.N.