1. Primary Ecological Succession
Occurs where there is no pre-existing vegetation and often no soil in an area.
Example = island formed by lava, area left by the retreat of a glacier.
Gradual growth of an ecosystem for the first time over a long period of time.

2. Primary Ecological Succession
Example = Melted Glacier
Example = animation of lava flow

3. Secondary Ecological Succession
*A process of gradual change that occurs following the destruction of an existing ecosystem to restore an area to it normal state.
*Destruction could be:
Fire, flood, plowing, deforestation, construction, tsunami, hurricane, etc.

4. *During the process, communities are replaced by other communities until the
Climax Community is reached = the final stable community of organisms with no significant change.
-The climax community is dependant on the BIOME of the area where the succession is occurring!

5. -Very slow process, may take decades to return to a normal state.
- As the producer communities change, so do the consumers.
-Very slow process, may take decades to return to a normal state.
- The climax community is stable, yet changing slightly.

8. Mt. St. Helen’s 1980

14. Example = A plowed field in York County, PA.
1. Destruction = plowing. Pioneer organisms (first organisms to occupy a recently disturbed area ex. Lichens, algae) move in and briefly become established in the area.

15. 2. Pioneer organisms are replaced by grasses and weeds.
Example = A plowed field in York County, PA.
2. Pioneer organisms are replaced by grasses and weeds.
Intermediate species

16. Example = A plowed field in York County, PA.
3. Small shrubs grow along with other grasses and weeds = more producers = more consumers move into the community.
Intermediate species

17. Example = A plowed field in York County, PA.
Saplings (young trees) grow (=Scrub forest) = less grasses and weeds due to shading = different consumers are attracted to the area.
Intermediate species

18. Example = A plowed field in York County, PA.
Forest matures = more canopy = less light to forest floor = different consumers.
The climax community has been reached, which, for this example, is a deciduous forest. This community will remain relatively stable until another destructive event occurs.