Download energy flow in ecosystems

ENERGY FLOW IN ECOSYSTEMS
CHAPTER 5
SECTION 1
Warm-up
• How is energy transferred fro one organism to
another?
• Why should forest rangers let some forest fires
burn?
• Write down three plants or animals and the
animals that eat them.
• Also write down any plants that you know eat
animals.
Did you know this?
• Some natural forest fires clear land of brush
and deadwood, cause the growth of new
vegetation for animals to eat, and kill
vegetation that competes with native plant
species.
Life depends on the Sun
Key Terms
Photosynthesis
From producers to consumers
Key Terms
Autotrophs, Producers
Heterotrophs, consumers
Do you think Clover plant is
important for coyote?
How does the coyote depend on the Sun?
An exception to the rule:
Deep-ocean Ecosystems
• http://www.extremescience.com/deep-sea-vents-video.htm
• Organisms that live in hydrothermal vent: clams, worms, mussels,
sponges, barnacles. These deep-ocean communities live in total
darkness, where photosynthesis cannot occur.
Bacterial live in these organisms and make use of hydrogen sulfide to
make their own
Food. Hydrogensulfide is
present in hot water that
escapes from cracks in the ocean
Floor. These bacteria are eaten
By other organisms and thus
Support a ecosystem
What eats what?
bcs.whfreeman.com
Key terms
•
•
•
•
•
Herbivores
Carnivores
Omnivores
Decomposers/detritivores
Role of decomposers: They break down dead
organic matter and allow the nutrients in the
rotting material to return to the soil, water,
and air. Example bacteria and fungi.
Math skill
• How many calories are there in 30lbs of
salmon if each pound of salmon = approx.654
cal?
• How many calories are there in 66 lbs of
blueberries if each pound of blueberries =
approx.261 cal?
• Do not use calculators.
Answers
• 30lbs x 654 = 19620 cal
• 66lbs x 261 cal = 17226 cal
Energy transfer
• Each time one organism eats another
organism, a transfer of energy occurs. We can
trace the transfer of energy as it travels
through an ecosystem by studying food
cahins, food webs, and trophic levels.
Food chain
Aquatic food chain
Food web
Key Terms
Trophic level
Shall we construct a class food web?
Or
Do you make a group Food Web?
DDT in an aquatic Food Chain
Read case study in Page number
120
Energy Pyramid
How energy loss affects an ecosystem
• There are fewer organisms at the higher trophic
levels. For example, zebras and other herbivores
outnumber lions on the African Savanna by about
100 to 1.
• The loss of energy from trophic level limits the
number of trophic levels in an ecosystem.
Ecosystems rarely have more than four or five
trophic levels because the ecosystem does not
have enough energy left to support higher levels.