1. Succession

2. Succession
Fire, floods, volcanoes, hurricanes, and other natural disasters can change communities in a short period of time.
Even without a disaster, communities change.
Succession
The natural processes by which one community of organisms slowly replaces another in a certain area.
2 Types
Primary
Secondary

3. Primary Succession Primary Succession Steps
The series of changes that occur in an area where no ecosystem previously existed.
Steps
Land created by volcanic eruption or retreat of glacier
No soil present
Pioneer Species
The first organisms to live in an area.
Usually lichens or mosses that grow on rocks
Break up the rocks to form soil.
Soil development
Seeds of plants land in new soil and begin to grow
Several hundred-thousand years

4. Primary Succession

5. Primary Succession

6. Secondary Succession Secondary succession
The series of changes that occur after a disturbance in an existing ecosystem.
Ex. Fires, hurricanes, tornadoes, farming, logging, or mining.
Occurs in a place where an ecosystem has previously existed
Occurs more rapidly than primary succession
Around 100 years

7. Secondary Succession

8. Secondary Succession

9. Succession Summary Succession Primary Secondary Creates new ecosystem
Restores previous ecosystem
Example:
New land created by volcanic eruption
An area destroyed by fire

10. Summary Questions How are primary and secondary succession different?
What is a pioneer species?
Give two examples of natural disturbances and two examples of human disturbances that can result in secondary succession.
Grass poking through the cracks in a sidewalk is an example of succession. Is this primary or secondary succession? Explain.