Transcript Energy and Nutrients

Energy Transfer & Nutrient
Cycling
How is energy transferred in an
ecosystem?

Organisms in a community survive by either
producing or consuming food
How is energy transferred in an
ecosystem?

Trophic levels levels of feeding in
a community
How is energy transferred in an
ecosystem?


Producers produce food for
themselves (ex.
plants),
Other organisms
may eat producers.
How is energy transferred in an
ecosystem?


Consumers - must
take in food (ex.
fungi)
Primary Consumers
- also called
herbivores (ex.
cow)
How is energy transferred in an
ecosystem?

Secondary and
Tertiary
Consumers - may
be carnivores (ex.
lion) or omnivores
(ex. bear)
How is energy transferred in an
ecosystem?

Decomposers - as
they consume, they
break down wastes
and dead
organisms and
return nutrients to
the soil.
Food Webs

Made up of
overlapping food
chains.
Food Webs


Shows feeding
connections; arrows
illustrate energy
transfer
Ex:
Fill It In …
Answer using the food
web:
1.
Organisms that
eat grass.
2.
Food sources for
the fox.
3.
An “omnivore”.
4.
An “herbivore”.
5.
A “carnivore”.
Ecological Efficiency


Producers have the
most available
energy (sun).
Energy is lost as it
moves up through
the food web; 10%
rule - only 10% of
the available energy
is passed to the
next trophic level.
Ecological Efficiency

The “lost” energy is used to catch, eat, and
digest food
Fill It In …
10% Rule:
Carnivores (_____ cal)
Herbivores (_____ cal)
Plants (1000 cal)
Check Yourself!
1.
What is a trophic level?
2.
What is the difference between an omnivore
and a carnivore?
3.
From the food web above, write out a food
chain that includes the rat.
4.
Which level in a food web has the most
energy?
Check Yourself!
1.
2.
What is a trophic level? LEVELS OF
FEEDING IN A COMMUNITY
What is the difference between an omnivore
and a carnivore?
3.
From the food web above, write out a food
chain that includes the rat.
4.
Which level in a food web has the most
energy?
Check Yourself!
1.
2.
3.
4.
What is a trophic level? LEVELS OF
FEEDING IN A COMMUNITY
What is the difference between an omnivore
and a carnivore? OMNIVORE EATS PLANTS
AND MEAT, CARNIVORE EATS ONLY
MEAT
From the food web above, write out a food
chain that includes the rat.
Which level in a food web has the most
energy?
Check Yourself!
1.
2.
3.
4.
What is a trophic level? LEVELS OF
FEEDING IN A COMMUNITY
What is the difference between an omnivore
and a carnivore? OMNIVORE EATS PLANTS
AND MEAT, CARNIVORE EATS ONLY
MEAT
From the food web above, write out a food
chain that includes the rat. (ANSWERS WILL
VARY)
Which level in a food web has the most
energy?
Check Yourself!
1.
2.
3.
4.
What is a trophic level? LEVELS OF
FEEDING IN A COMMUNITY
What is the difference between an omnivore
and a carnivore? OMNIVORE EATS PLANTS
AND MEAT, CARNIVORE EATS ONLY
MEAT
From the food web above, write out a food
chain that includes the rat. (ANSWERS WILL
VARY)
Which level in a food web has the most
energy? PRODUCER
How is matter reused in an
ecosystem?



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Role of decomposers
Decomposers break
down wastes and dead
organisms
Decomposition allows
nutrients to be returned
to the soil and
atmosphere; this allows
nutrients to be reused.
Decomposers include
fungi, bacteria, and
invertebrates
How is matter reused in an
ecosystem?
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
Biogeochemical
Cycles - the pathway
through which a
substance is recycled
Water cycle
– Enters ecosystem by
precipitation; may
infiltrate the soil (be
absorbed) or run-off into
surface water
How is matter reused in an
ecosystem?

Water cycle
– Returned to atmosphere
by evaporation or
transpiration (the loss
of water by plants)
Fill It In …

Diagram of water cycle:
How is matter reused in an
ecosystem?

Carbon cycle
– Powered by two
main processes
– Photosynthesis plants and algae
capture CO2 from
the air and change it
into sugar (which
have carbon)
How is matter reused in an
ecosystem?

Carbon cycle
– Respiration - all
living things break
down sugars for
energy, which
returns CO2 to the
atmosphere
How is matter reused in an
ecosystem?

Carbon cycle
– Other factors in the
carbon cycle:
– Decomposition
returns carbon to
the soil and
atmosphere
How is matter reused in an
ecosystem?

Carbon cycle
– Humans burn fossil
fuels which adds
CO2 to the
atmosphere
– Deforestation
removes tress which
normally
photosynthesis and
remove CO2 from
the atmosphere
How is matter reused in an
ecosystem?
Fill It In …
Factors that ADD carbon to atmosphere:
Factors that REMOVE carbon from
atmosphere:
Using the Carbon Cycle diagram
on page 77 of textbook:
1.
2.
3.
4.
5.
6.
7.
What are the 4 sources/processes that ADD carbon
to the atmosphere?
What are the 2 sources/processes that REMOVE
carbon from the atmosphere?
What process do animals carry out that adds CO2 to
the atmosphere?
What process do plants carry out that removes CO2
from the atmosphere?
The combustion of _______ by humans can add CO2
to the atmosphere.
______ of dead organisms may return carbon to the
soil.
How is carbon stored in plants transferred to
animals?
How is matter reused in an
ecosystem?

Nitrogen Cycle
– Nitrogen is essential
for living organisms
so that they can
build proteins;
nitrogen is plentiful
in the atmosphere,
but is not usable in
this form.
How is matter reused in an
ecosystem?

Nitrogen Cycle
– Nitrogen fixation bacteria living in the
root nodules of bean
plants (legumes)
convert nitrogen from
the air into a more
usable form.
How is matter reused in an
ecosystem?

Nitrogen Cycle
– Nitrogen fixation is
the first of many
steps that involves
bacteria and
changing the form of
nitrogen.
Check Yourself!
1.
How do decomposers help with the recycling of
nutrients?
2.
How do plants return water to the atmosphere?
3.
What two processes drive the carbon cycle?
4.
What organisms are essential for the conversion
of nitrogen?
Check Yourself!
2.
How do decomposers help with the recycling of
nutrients? BREAK DOWN WASTES & DEAD
ORGANISMS TO ALLOW NUTRIENTS TO BE
RETURNED TO THE SOIL OR ATMOSPHERE
How do plants return water to the atmosphere?
3.
What two processes drive the carbon cycle?
4.
What organisms are essential for the conversion
of nitrogen?
1.
Check Yourself!
1.
2.
3.
4.
How do decomposers help with the recycling of
nutrients? BREAK DOWN WASTES & DEAD
ORGANISMS TO ALLOW NUTRIENTS TO BE
RETURNED TO THE SOIL OR ATMOSPHERE
How do plants return water to the atmosphere?
TRANSPIRATION
What two processes drive the carbon cycle?
What organisms are essential for the conversion
of nitrogen?
Check Yourself!
1.
2.
3.
4.
How do decomposers help with the recycling of
nutrients? BREAK DOWN WASTES & DEAD
ORGANISMS TO ALLOW NUTRIENTS TO BE
RETURNED TO THE SOIL OR ATMOSPHERE
How do plants return water to the atmosphere?
TRANSPIRATION
What two processes drive the carbon cycle?
PHOTOSYNTHESIS & RESPIRATION
What organisms are essential for the conversion
of nitrogen?
Check Yourself!
1.
2.
3.
4.
How do decomposers help with the recycling of
nutrients? BREAK DOWN WASTES & DEAD
ORGANISMS TO ALLOW NUTRIENTS TO BE
RETURNED TO THE SOIL OR ATMOSPHERE
How do plants return water to the atmosphere?
TRANSPIRATION
What two processes drive the carbon cycle?
PHOTOSYNTHESIS & RESPIRATION
What organisms are essential for the conversion
of nitrogen? BACTERIA