1. Cycles of Matter
Ecology

2. Energy Pyramid
The above energy pyramid shows many trees & shrubs providing food and energy to giraffes. Note that as we go up, there are fewer giraffes than trees & shrubs and even fewer lions than giraffes. In other words, a large mass of living things at the base is required to support a few at the top.

3. Energy Pyramid
Only part of the energy that is stored in the 1st trophic level is passed to the 2nd level
Only part of the energy that is stored in the 2nd trophic level is passed to the 3rd level
3rd trophic level
2nd trophic level
1st trophic level

4. Energy Pyramid
Only part of the energy stored in one trophic level is passed to the next level because organisms use much of the energy that they consume for respiration, movement, and reproduction and some energy is released into the environment as heat.

5. Energy Pyramid Most food chains have no more than four or five links.
There cannot be too many links in a single food chain because the animals at the end of the chain would not get enough food (and hence energy) to stay alive.
Most animals are part of more than one food chain and eat more than one kind of food in order to meet their food and energy requirements. These interconnected food chains form a food web.

6. Energy Pyramid
A change in the size of one population in a food chain will affect other populations. This interdependence of the populations within a food chain helps to maintain the balance of plant and animal populations within a community. For example, when there are too many giraffes; there will be insufficient trees and shrubs for all of them to eat. Many giraffes will starve and die. Fewer giraffes means more time for the trees and shrubs to grow to maturity and multiply. Fewer giraffes also means less food is available for the lions to eat and some lions will starve to death. When there are fewer lions, the giraffe population will increase.

7. Productivity
The rate at which light energy is converted to chemical energy by the producers of an ecosystem
10% of the available energy on one level is passed to the next level

9. Energy flow

10. Biomass The mass (weight) of biotic factors in an area
A biotic factor is anything that is living
In most biomass pyramids the producers have the greatest mass by far.

11. Pyramid Models Chapter 13 Section 6
Ecological Pyramids
Section 3-2
Energy Pyramid
Shows the relative amount of
energy available at each trophic
level. Organisms use about 10
percent of this
energy for
life processes.
The rest is lost
as heat.
Pyramid of Numbers
Shows the relative
number of individual
organisms at each
trophic level.
Biomass Pyramid
Represents the amount of
living organic matter at each
trophic level. Typically, the
greatest biomass is at the
base of the pyramid.
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12. Recycling Matter
Matter is not used up in an ecosystem. Matter is transformed.
Imagine that you are a carbon atom in a molecule of CO2 floating in the air. The leaf of a blueberry bush absorbs you during photosynthesis. You become part of a carbohydrate molecule and are used to make a blueberry. The blueberry is eaten by a moose, and within a few hours, you are passed out of the animals body. You are soon swallowed by a dung beetle, and then eaten by a hungry shrew, which in turn is eaten by an owl. Finally, you are released into the atmosphere once again as CO2 when the owl exhales. Then, the cycle starts over again.

13. Cycles of Matter
All ecosystems need energy to survive. But all organisms need more than just energy, they also need water, minerals, and other compounds.
Most organisms are chiefly made up of just four elements:
Hydrogen
Oxygen
Carbon
Nitrogen

14. Recycling Matter The same molecules are passed around
Energy and matter move through the biosphere very differently
Energy flows in one direction, from the producers to consumers
Matter is recycled within and between ecosystems
The same molecules are passed around
again and again within an ecosystem

15. The Water Cycle All living things require water to survive.
Water is H20.
Water moves between the ocean, atmosphere, and land via 4 different processes
Evaporation and transpiration
Condensation
Precipitation

16. The Water Cycle
Evaporation – the process that changes water from a liquid in the ocean and other bodies of water to a gas in the atmosphere
Transpiration – loss of water from the leaves of plants into the atmosphere
Condensation – the process that forms clouds
Precipitation – rain, snow, sleet or hail

17. The Water Cycle

18. Nutrient Cycles
Nutrients – all the chemical substances that an organism requires to live
Like water, nutrients are passed between organisms and the environment
The Carbon Cycle
The Nitrogen Cycle
The Phosphorous Cycle

19. The Carbon Cycle Carbon is the key ingredient in all living things.
Carbon is also found
in the ocean, air, and rocks.
Carbon is present in the atmosphere as CO2 gas.
Carbon is cycled through the atmosphere by many different processes.

20. The Carbon Cycle
CO2 is released into the atmosphere by volcanoes, respiration, burning of fossil fuels, and decomposition.
Plants use CO2 to make carbohydrates
Carbohydrates are passed along food webs to animals and other consumers
Carbon is present in the ocean as calcium carbonate in the bones and shells of marine organisms

21. The Carbon Cycle
images/carboncycle.jpg

22. The Nitrogen Cycle All organisms require nitrogen to make proteins
Nitrogen gas makes up 78% of the Earth’s atmosphere
Nitrogen is found in:
Waste products of many organisms and in dead and decaying organic matter
The ocean
Fertilizer

23. The Nitrogen Cycle
Only certain types of bacteria can use nitrogen gas. These bacteria convert nitrogen gas into ammonia in a process called nitrogen fixation.
Other bacteria convert ammonia into a form that producers can use to make proteins.
Consumers then eat the producers and reuse the nitrogen to make their own proteins.

24. The Nitrogen Cycle
When organisms die, decomposers return nitrogen to the soil as ammonia.
Nitrogen gas is returned to the atmosphere in a process called denitrification.

25. The Nitrogen Cycle N2 Plants produce carbohydrates Ammonia
Nitrogen Fixation

26. The Nitrogen Cycle N2
Ammonia
Decomposition
Denitrification

27. The Phosphorous Cycle Part of DNA and RNA Not common in the biosphere
Does not enter the atmosphere
Remains mostly on land in rock, soil minerals and ocean sediment

28. Phosphorous Cycle
Rocks and sediments gradually wear down and phosphate is released
Some makes its way to the ocean to be used by marine organisms
Some stays on land and cycles between organisms and the soil

29. The
Phosphorous
Cycle