1. Succession Ecosystems are NOT static, they are constantly changing
Natural forces and human activity disturb them
Ecological succession - series of changes that occur over time in an ecosystem
Organisms occupy a site & change the environment so that other organisms can come in
Two Types:
Primary succession
Secondary succession

2. Primary Succession
Primary succession - happens on surfaces where no soil exists (lifeless ground).
Examples
after a volcanic eruption
after a glacier melts

3. Primary Succession Steps
1. Pioneer species arrive (lichens): don’t need soil to survive
2. Lichens die & decompose  organic matter mixes with rock to start making soil
3. Mosses & ferns can grow in new soil  die & add more nutrients to soil
4. Grasses & wildflowers can move in  die & add more nutrients to soil
5. Shrubs & trees can survive
6. End in Climax community

4. Pioneer species
Climax Community
First set of species to establish themselves
Grow rapidly
Short lived
Do well in bright sunlight where nutrients are abundant
Seeds are widely and rapidly disbursed
lots of hardwood
shade-loving trees

6. Secondary Succession
Secondary succession – ecosystem is disturbed but soil is not removed (previous ecosystem remains)
Examples
cleared farming fields
forest fires
flood
tornado
Soil & seeds still present, so takes shorter amount of time
Start with grasses  herbs, shrubs, small trees  hardwood trees (climax community)

8. Succession Time Line ***Be sure to label each picture
Primary Succession
Secondary Succession
Start with a picture that represents a natural occurrence that would wipe out top soil. Ex: fire, mudslide, deforestation
Start with weeds
Shrubs/ bushes
pine
mature hardwoods
Start with a picture that represents a natural occurrence that would wipe out top soil. EX: erosion, glacier movement, volcanic eruption.
Rocks or Earth’s crust with no top soil.
Pioneer Species
Small shrubs/bushes
Pines
Mature hard woods
***Be sure to label each picture

9. When finished, write 2 paragraphs on your construction paper to describe the following:
Paragraph # 1: Primary Succession
Explain the steps of succession.
What traumatic events would cause this re-growth to occur?
What are pioneering plants? What are some examples of these?
Explain why this type of succession takes longer than secondary.
Paragraph #2: Secondary Succession
Explain the steps of secondary succession.
Why would pioneer plants not be needed?
What do secondary successions have that primary successions do not?