Energy Flow in the Ecosystem

1
Energy Flow in the Ecosystem

• Chapter 5

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Life Depends of the Sun

• Energy enters the ecosystem through the process
  of Photosynthesis.
• Energy moves from producers to consumers.

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Life Depends of the Sun

• Producer- Autotroph (self feeder)
• Consumer- Heterotroph (must eat something else to
  get energy)
• Exception to Rule- Deep Ocean Ecosystems

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What Eats What
5
Cellular Respiration Burning the Fuel

• Cellular Respiration- process of breaking down
  food to obtain energy for growth and daily
  functions.

6
Energy Transfer

• Each time one organism eats another energy is
  transferred.
• We can trace energy transfers through food
  chains, food webs, and trophic levels.

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Energy Transfer

• Food Chain- a sequence of energy transferred from
  one organism to another.

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Energy Transfer

• Food Web- shows many feeding relationships that
  are possible in an ecosystem.

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Energy Transfer

• Trophic Levels- each step in a transfer of energy
  through a food chain or food web in an ecosystem.
  
• Each time energy is transferred from one organism
  to another some energy is lost to heat and less
  energy is available to the organism at the next
  level.

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Energy Transfer

• Organisms use much of their energy to carry out
  life functions like growing new cells, regulating
  body temperature, and moving.
• About 90 of the energy at each trophic level is
  used in this way. The remaining 10 is available
  at the next trophic level.

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Energy Transfer

• Energy Pyramids

12
Biological Magnification

• Biological Magnification- poisons that dissolve
  in fat can become more concentrated as the move
  up the food chain.

13
The Cycling of Materials

• Carbon Cycle- carbon is an essential component of
  proteins, fats, and carbohydrates.

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Cycling of Materials

• Long terms cycles
• Carbonates- shells, limestone
• Carbon sinks- carbon reserves in the earth
• Fossil Fuels- carbon that what stored in bodies
  millions of years ago.
• Human affects of the carbon cycle
• When we burn fossil fuels and wood we add Carbon
  dioxide to the atmosphere.

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Cycling of Materials
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Cycling of Materials

• The Nitrogen Cycle-
• All organisms need nitrogen to build proteins
• 78 of the earths atmosphere is made up of
  nitrogen but it is NOT usable by most organisms
  in this form.
• A few species of bacteria can convert nitrogen
  from the atmosphere into a usable compound-
  Nitrogen fixing Bacteria

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Cycling of Materials
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Cycling of Materials
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Cycling of Materials

• The Phosphorus Cycle-

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Cycling of Materials

• Fertilizers
• Fertilizers containing Nitrogen and phosphorus
  are added to soil to increase plant growth.
• Excess fertilizers can end up in water ways
  causing eutrophication (an algal bloom)
• Acid Precipitation-
• Burning of coal and other fossil fuels adds
  nitric oxide to the atmosphere. When added to
  rain water it produces acid rain.

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How Ecosystems Change

• Ecological Succession- the gradual process of
  change and replacement of species in a community.
• Primary Succession- the type of succession that
  occurs where no ecosystem previously existed.
• Ex- new volcanic islands, areas exposed by
  glacial retreats, parking lots
• Slow process- soil must be formed from broken
  down rock. (hundreds to thousands of years to get
  fertile soil)
• Pioneer species- first species to colonize newly
  available area.
• Ex.-bacteria and lichens

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How Ecosystems Change

• Secondary Succession- the type of succession that
  occurs where an ecosystem previously existed.
• Fire- required for certain ecosystems to be
  maintained.
• Old field succession- occurs when farm land is
  abondoned.

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How Ecosystems Change
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How Ecosystems Change
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How Ecosystems Change
Old- Field Succession
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How Ecosystems Change

• Climax community- a mature stable community where
  the type of ecosystem will remain basically
  unchanged unless it is altered.