1. 2.3 Ecosystems are always changing
Population size changes in response to
food supply
Predation
Seasons
birth rates

2. A limiting factor, such as water, light, or food, can affect population survival and growth.
The carrying capacity of an environment is the maximum population it can support. At carrying capacity a population stops growing.

3. Ecosystems change over time.
Succession is a gradual series of changes that take place in an ecosystem after a disturbance.
There are two types of succession
Primary
Secondary

4. Primary - starts from an environment that is mostly empty of life.
Examples - After the retreat of a glacier, for example, or on new rock produced by a volcano, life can begin to return

5. Pioneer species - 1st species that moves into the barren environment and begin the task of creating soil.
Examples: moss, lichen

6. Secondary - occurs in areas that have soil with roots and seeds below the surface.
life already survives.
may begin after a fire or flood disturbs the ecosystem.