Here are the key points about how energy flows through ecosystems: - Energy from the sun is captured by producers (plants) through photosynthesis and stored as chemical energy in glucose. - Primary consumers (herbivores) obtain energy by eating producers. Secondary consumers (carnivores) obtain energy by eating primary consumers. Tertiary consumers obtain energy by eating secondary consumers. - Most energy is lost at each transfer between trophic levels, so the amount of available energy decreases moving up the food chain. - Scavengers and decomposers (bacteria, fungi) break down dead organisms, recycling nutrients back into the soil/environment where producers can use them again. - Nutrient cycling

1. Ecosystems and You
Ms. Thao Le

2. Energy Flow Through An Ecosystem
Learning Goals:
• Explain how energy flows through an
ecosystem
• Describe how energy flow can be represented
in an ecosystem
• Identify the key actors that contribute to
energy flow in an ecosystem
• Explain the importance of nutrient cycling

3. Energy Flow Through An Ecosystem
• What do you already know?
• Who are the key players in an ecosystem
• How is energy flow represented in an
ecosystem?
1. Food Chain + Nutrient Cycle
2. Food Pyramid + Nutrient Cycle

4. Ecosystem
What is an ecosystem?

5. Ecosystem
Climate
Animals Soil
Vegetation

6. Ecosystem
• An ecological
community consisting of
plants and animals living
together in a particular
environment.
• They depend on each
other and the non-living
parts of their
environment such as
rocks, soil, water,
sunlight, and
temperature.

7. Energy
How does energy flow through an ecosystem?

8. http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/ecosystem/zebra2.gif

9. Energy Flow Through An Ecosystem
• Sun
• Consumers
1. Primary
2. Secondary
3. Tertiary
• Decomposers +
Nutrient Cycling

10. Energy Flow Through An Ecosystem
• Starts with the Sun (Our largest
energy source on Earth!)
• Photosynthesis-The chemical
reaction by which green plants
use water, carbon dioxide and
light from the sun to make
glucose.
• ENERGY is stored in glucose;
glucose is stored as starch.

11. Energy Cycle

12. Energy Flow Through An Ecosystem
• Organisms that can make
their own (energy) in the
form of glucose are called
Producers.
• Examples: Plants, Algae
• The energy that is unused
by producers are passed on
to organisms that cannot
make their own energy
called Consumers.
• Examples: Fish, Dog, Cat,
Tiger, You

13. Energy Flow Through An Ecosystem
Types of Consumers:
• Primary Consumer- 1st Order, ex: Herbivores=
Plant eaters
• Secondary Consumer-2nd Order, Consumers to
eat another consumer, ex: Herbivores,
Carnivores=Meat eaters
• Tertiary Consumer-3rd Order, A consumer that
eats a consumer that already ate a consumer
• Scavengers + Decomposers-Getting read of dead
stuff, returning energy into nutrient form

14. Energy Flow Through An Ecosystem
• Most of the energy
the primary
consumer gets from
the producer is used
by the consumer.

15. Energy Flow Through An Ecosystem

16. Energy Flow Through An Ecosystem

17. Energy Flow Through An Ecosystem

18. Energy Flow Through An Ecosystem
• Scavengers-they eat dead
stuff. Ex: Vultures
• Decomposers-they breakdown
what the scavengers eat to
return the energy back into
the soil where plants can use
it. Ex: Worms, Insects, Bacteria
• Nutrient Cycling :(C, O, H, N,
P). Ex: Worms using nutrients
(minerals) in soil or Algae
using Phosphorus in a body of
water.

19. Energy Flow Through An Ecosystem

20. Energy Flow Through An Ecosystem

21. Energy Flow Through An Ecosystem

22. Energy Flow Through An Ecosystem
• Energy is not recycled; it is constantly being
supplied by the Sun.
• Energy is lost in the form feces, tissue loss,
and death which releases heat.
• Nutrients are recycled as there is only a
limited supply.

23. Energy Flow Through An Ecosystem
• The transfer of energy
from sun to producer
to primary consumer
to secondary
consumer to tertiary
consumer can be
shown in a FOOD
CHAIN.

24. Energy Flow Through An Ecosystem
• Another way of
showing the transfer
of energy in an
ecosystem is the
ENERGY PYRAMID.

25. Energy Flow Through An Ecosystem
Food Pyramids Show:
• That the amount of
available energy decreases
down the food chain
• It takes a large number of
producers to support a
small number of primary
consumers
• It takes a large number of
primary consumers to
support a small number of
secondary consumers

26. Energy Flow Through An Ecosystem
Help me classify which role these organisms in
the videos represent in a food chain:
• http://www.youtube.com/watch?feature=play
er_embedded&v=HN9j0y9bivo
• http://www.youtube.com/watch?feature=play
er_embedded&v=xFQ_fO2D7f0

27. Energy Flow Through An Ecosystem
• What is an ecosystem?
• How does energy flow through an ecosystem?
• Describe how the transfer of energy can
berepresented? (Hint: We reviewed 2 types.)
• Identify the key players in an ecosystem.
• Why is nutrient cycling important?

28. Energy Flow Through An Ecosystem