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 (not even soil) 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 (soil remains)
Example: forest fire
Occurs faster than primary succession

5. Climax community
Community reaches a steady state
Before
After

6. Human Activities vs. Ecosystem
Deforestation – The clearing of forest for agriculture, lumber, and other uses
eliminating plants = more CO₂ in air
Greenhouse Effect – the natural process by which atmospheric gases trap heat
Add CO2 = global warming

7. Human Activities vs. Ecosystem
Acid Rain – the precipitation that contains nitric and/or sulfuric acids.
Pollution – The addition of substances to the environment that results in a negative effect.

8. Invasive Species Example: 1. Burmese Python in The Everglades
Invasive species - Species that does not belong in a specific area (foreign)
Cause excessive damage to the new environment
Lacks natural predator, so it’s population can increase a lot
In turn, drastically decreases the populations of it’s prey
Example:
1. Burmese Python in
The Everglades
2. Lion fish

9. Aquatic Ecosystems 1. Photic zone – surface where the sun reaches
Photosynthesis occurs
Warmer water
2. Aphotic zone – the sun does not reach
No photosynthesis
Colder water
Benthic zone – ocean or
pond floor (cold, no light)