1. Succession Notes

2. Range of Tolerance
Optimum Range
Stress Zone
Intolerance Zone

3. Limiting Factors
Sunlight
Water/Humidity
Nutrients

4. Succession
The change in biological communities of an area over a long period of time

6. Two Types of Succession:
Primary
Initial establishment & development of a community
occurs on barren rock volcanic eruption, glacial retreat, pavement
Secondary
Reestablishment of a community
remnants of previous community is still there abandoned field, after fire, flood, or hurricane

7. Primary Succession:

8. Secondary Succession:

9. Stages of Succession: Bare Rock
No soil, no available nutrients, no active life……not a community

10. Stages of Succession: Lichens & Mosses Pioneer Species
First to colonize rocks
secrete acid onto rock which liberates nutrients that can be absorbed
catches wind-blown dirt
can take 100s to 1000s of years
very vulnerable to erosion
least diverse and least stable

11. Stages of Succession: Grasses & Shrubs Early Succession Plants
don’t need deep soil
like full sun
shrubs move in and shade out grasses, killing them

12. Stages of Succession: Softwood Early Mid-succession Plants
trees that need a lot of sunlight
Cedar, pine, aspen, locust
Trees displace grasses and shrubs

13. Stages of Succession: Mid-succession Plants
Tulip, ash, red maple, birch
Displace the soft woods

14. Stages of Succession: Mixed Hardwood Mature Forest
deciduous trees; oaks, maples, hickories, beech
saplings are shade-tolerant for the first few years
when an adult tree dies it leaves a hole in the canopy
saplings race to the top, grow tall quickly-not wide
then grow slowly
Most Diverse, least likely to erode, very productive
Dominant species is reproducing, therefore climax stage

15. Questions
What is the difference between primary and secondary succession?
What types of events can cause secondary succession?
What are some abiotic and biotic factors that play a part in succession?
How can humans cause succession?

16. Big Question
How does the ecosystem change as it moves through the stages of succession?