1. Succession in Ecosystems

2. Succession
A series of changes in a community in which new populations of organisms gradually replace existing ones
Two types:
primary succession
secondary succession

3. Primary succession-
colonization of new sites by communities of organisms
takes place on bare rock where no life had existed before

4. Example: volcanic lava flow cools and forms rock
Glaciers retreat and expose rock

5. Pioneer organisms - the first organisms to colonize a new site
Ex: lichens are the first to colonize lava rocks

6. Climax community-
a stable, mature community that undergoes little or no succession
ex. In most of Maryland, the climax community would be a deciduous forest

7. Your turn
Draw and label an example of primary succession. Starting with a bare rock

8. Primary succession-

9. Secondary succession
sequence of community changes that takes place when a community is disrupted by natural disaster or human actions
takes place on existing soil

10. Example: A fire levels portions of a forest
A farmer plows his field

11. Your turn
Draw and label an example of secondary succession. Starting with a forest fire

12. Secondary succession-

13. Pond Succession