1. How Ecosystems Work
Chapter 5

2. Energy flow in the Ecosystem
Life depends on the sun in a process called photosynthesis
Plants, algae and some bacteria capture solar energy and with Carbon Dioxide CO2 and Water H2O make Oxygen O2 and sugar or glucose C6H12O6
6CO2 + 6H2O + sun = C6H12O6 + 6O2
All organisms ultimately get their energy from the sun

3. 6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 + 6O2
Energy Flow Through an Ecosystem
Begins with the SUN
Photosynthesis
6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 + 6O2

4. Producers use most of the energy they make for themselves.
Organisms that can make glucose during photosynthesis are called
Producers use most of the energy they make for themselves.

5.
The energy that is not used by producers can be passed on to organisms that cannot make their own energy.

6. Organisms that cannot make their own energy
CONSUMERS
Organisms that cannot make their own energy

7. Consumers eat producers to get energy:
Most of the energy is used by the consumer but some of the energy moves into the atmosphere as heat.
Consumers eat producers to get energy:
Herbivores- eat plants
Omnivores – eat
Plants and animals
Carnivores – eat animals

8. An Exception to the Rule:
Deep Ocean Ecosystems
Hydrothermal Vent
Bacteria use Hydrogen
Sulfide from the hot
water to make their
own food
Thus they are producers!

9. Decomposers Breaks down dead organisms in an ecosystem and returns
nutrients to
soil, water and air
Bacteria and Fungi

10. Cellular Respiration Burning the Fuel
CELLULAR RESPIRATION is the chemical reaction that releases the energy in glucose
Excess energy is stored as fat
6O2 + C6H12O6 -->> 6H2O + 6CO2 + energy

11. Food Webs: Are interconnected food chains
They show the feeding relationships in an ecosystem

12. FOOD CHAIN – shows the transfer of energy from the sun to producer to primary consumer then to higher order consumers

13. Food Chains Show Available Energy
Trophic
Levels

14. Energy Pyramid
Amount of available energy decreases for higher consumers
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

15. Envi Sci 1/19/11 Stamp then go over food chain/web worksheet
Case Study page
Finish up notes…
Tomorrow Library. Biome Project!!

16. The Cycling of Materials
Carbon Cycle
Cycled between the atmosphere, land, water and organisms
Carbon is the basic building block for all living organisms
It is moved through the atmosphere by plants/animals in CO2/O2 exchange through breathing and photosynthesis
Large carbon deposits exist in the oceans and soil from dead organisms in the form of carbonates or carbon sinks of limestone

17. How Humans Affect the Carbon Cycle
When we burn fossil fuels we release carbon into the atmosphere
In /3 of all carbon dioxide emitted in the US was from motor vehicles
6 Billion metric tons of carbon a year released as CO2 into the atmosphere
50% of this remains in the atmosphere which contributes to global warming
1 Billion metric tons of CO2 are dissolved into the ocean – carbon sink
Plants absorb the remaining CO2

18. Carbon Cycle

19. Nitrogen Cycle
Although the atmosphere is 78% organisms cannot utilize nitrogen in that form
Nitrogen Fixing Bacteria – alter the Nitrogen to make it usable for all organisms
This bacteria lives on nodules of roots
Nitrogen is essential for plant growth, obtained through soil
Nitrogen can be found in all waste products of animals

20. Nitrogen Cycle

21. Phosphorous Cycle Phosphorous is stored in rocks and soil
Phosphorous is then moved through the rock and water cycle
Plants and animals take in phosphorous

22. Phosphorous Cycle

23. Acid Precipitation
When fuel is burned, large amounts of nitric oxide is release into the atmosphere.
In the air, nitric oxide can combine with oxygen and water vapor to form nitric acid.
Dissolved in rain or snow, the nitric acid falls as acid precipitation.

24. Fertilizers and the Nitrogen and Phosphorus Cycles
Excess fertilizer causes excess nitrogen and phosphorus can cause rapid growth of algae.
Excess algae can deplete an aquatic ecosystem of important nutrients such as oxygen, on which fish and other aquatic organisms depend.

25. Ecological succession is a gradual process of change and replacement of the types of species in a community.
Primary succession is a type of succession that occurs on a surface where no ecosystem existed before
Secondary succession occurs on a surface where an ecosystem has previously existed. can occur in ecosystems that have been disturbed or disrupted by humans, animals, or by natural process such as storms, floods, earthquakes, or volcanic eruptions.

26. A pioneer species is a species that colonizes an uninhabited area and that starts an ecological cycle in which many other species become established
A climax community is the final, stable community in equilibrium with the environment.

27. Ecological Succession

28. Succession Collage Create a scenario:
Primary Succession – initial growth (new volcano, island, receding sea)
Secondary Succession – calamity, disaster natural or man made
Cut out pictures of your area to represent each stage of succession
Describe each stage and give a rationale for it

29. Ecological Succession
Primary succession can occur
on new islands created by volcanic eruptions
in areas exposed when a glacier retreats
any other surface that has not previously supported life
Primary succession is much slower than secondary succession. This is because it begins where there is no soil.
The first pioneer species to colonize bare rock will probably be bacteria and lichens, which can live without soil.
The growth of lichens breaks down the rock, which with the action of water, begins to form soil.