1. Ecosystems

2. Ecological Succession
Ecological succession – changes that occur in a community over time
Especially after disturbances
Some species die, other species move in
Does not follow the same path each time

3. Primary Succession
Succession in an area where there are no remains of an older community
Example: volcanic explosion
Pioneer species – the first species to inhabit an area
Example: lichen

4. Secondary Succession
Succession when a community is destroyed, but not completely
Example: forest fire
Occurs faster than primary succession

5. Climax community
Community reaches a steady state
Before
After

6. Aquatic Ecosystems Photic zone – surface where the sun reaches
Photosynthesis occurs
Warmer water
Aphotic zone – the sun does not reach
No photosynthesis
Colder water