1. Cycles of Matter - Biogeochemical Cycles
Objective:
A5 - Describe the flow of matter through the carbon & nitrogen cycles & explain the consequences of disrupting these cycles

2. All matter cycles…it is neither created nor destroyed; it is just transformed
Unlike the one-way flow of energy, matter is recycled within & between ecosystems.
Elements pass from one organism to another and among parts of the biosphere through closed loops called biogeochemical cycles, which are powered by the flow of energy.

3. What is Carbon? Carbon is an element that is in all living things.
Molecules containing carbon are called Organic.

4. Carbon Cycle
Talk about Photosynthesis & Cellular Respiration
The movement of carbon from the environment into living things and then back again.

5. Carbon Cycle
Keep in mind all living things have carbon in them, so when they die, decomposers help return that carbon to the environment and soil.

6. What is Nitrogen?
Nitrogen is an element used to build proteins and nucleic acids.
It is found in living things like plants & animals and non-living things like the air above and the dirt below.

7. Nitrogen Cycle
Nitrogen atoms do not stay in one place. They move slowly between living things, dead things, the air, soil and water.

8. Nitrogen Cycle
Nitrogen fixation is when lightning or bacteria in the soil change nitrogen gas into a form that can be taken up by plant roots.

9. Nitrogen Cycle
Other bacteria obtain energy by converting the nitrogen in the soil back into a gas to be released into the air in a process called denitrification.

10. Ecological Succession
Objective:
A6 - Describe how events & processes that occur during ecological succession can change populations & species diversity

11. Ecological Succession is…
series of predictable changes that occurs in a community over time
Succession occurs in all natural environments.
There are 2 different types:
Primary
&
Secondary

12. Ecological Succession
1st year Grass
2nd year Grass Weeds
3rd to 18th year Grass, weeds, shrubs, pine tree seedlings
19th to 30th year Grass, weeds, shrubs, Young pine forest
30th to 70th year Mature pine forest; Understory of young hardwoods
70th to 100th year Pine to hardwood transition
100th year plus
Climax oak-hickory forest

13. Primary Succession
succession that occurs on the surface where no soil exists
Example:
new lava or rock from a volcano that makes a new island
Pioneer Species – first species to populate an area during primary succession

14. Primary Succession
6/5/03
M-DCC / PCB 2340C

15. Secondary Succession
succession following a disturbance that destroys a community without destroying the soil

16. The Circle of Life in Secondary Succession

17. Climax Community
A mature, stable community that is the final stage of ecological succession.

18. Examples of Climax Communities