Notes: Changes in Ecosystems:
Ecological Succession
Definition of Ecological Succession:
Primary Succession:
__________________________, _______________________changes in the types of species that live in an
area; can be primary or secondary
The gradual replacement of one plant _____________________by another through natural processes over
time
Stage 1:
Begins in a place without any ________________
Examples:
1. ______________________________
2. ______________________________
3. ______________________________
Stage 2:
Starts with the arrival of living things such as lichens that do not need soil to survive
Called ___________________ ___________________
What is a Lichen? A symbiotic relation ship between a___________________ and __________________
Stage 3:
•Soil starts to form as ____________________ and the forces of _____________________and erosion help
break down rocks into smaller pieces
* When lichens die, they _____________________, adding small amounts of organic matter to the rock to
make _________________
* Simple plants like __________________and ____________can grow in the new soil
Stage 4:
* The simple plants ___________, adding more organic ______________________
* The soil layer thickens, and______________, __________________and other
________________begin to take over
* These plants die, and they add more _________________________ to the soil
* ________________ and ________________ can survive now
Stage 5:
* __________________, ____________________ and ____________________ have begun to move in.
* What was once bare _______________ now supports a variety of _____________
Secondary Succession:
*Begins in a place that already has _________________and was once the home of living organisms
*Occurs ______________________and has different pioneer species than primary succession
Example: _______________________________________
Climax Community:
* A stable group of _______________________and ___________________that is the end result of the
succession process
* Does not always mean ___________________ ___________________.
Examples:
1. ________________________________
2._________________________________