1. SUCCESSION

2. Communities Change Over Time
Succession: a process of community development that involves a changing sequence of species

3. Species land on new material and colonize (pioneer community).
Primary Succession
Starts with new land.
Species land on new material and colonize (pioneer community).
Starts with lichens, moss, and progresses to large trees after 1,000’s of years.

4. 1) Lichens: Can be N fixers  Put Nitrate into soil for other plants to grow!

5. 2) Small Shrubs and mosses (little roots), provide habitat

6. 3) Young pine trees more habitat

7. 4) Mature hardwood and deciduous forests climax community

8. Secondary Succession Starts with already formed land.
Species land on disturbed material.
Disturbance usually caused by fires, storms, and man.

10. Fire Succession in Chaparral
Needed for:
Reproduction
Clearing out competitors
Germination (seed sprouting)

11. As Ecosystems Mature Increase in: Diversity & pop numbers
System stability
Biomass
Nutrient Hold Capacity