1. IN: Describe an example of how natural or human disturbances can change an ecosystem.

2. Ecological Succession

3. Ecological Succession
A series of environmental changes
As an ecosystem changes, older inhabitants gradually die out and new organisms move in, causing further changes in the community
Biodiversity increases

4. Primary Succession
On land, succession that occurs on surfaces where no soil exists is called primary succession
Example: Volcanic eruptions, glaciers
First species to populate =
Pioneer species

5. Primary Succession
Lichen (algae and fungi) are the first to grow on the volcanic rocks
They help break up the volcanic rocks
When the lichen die, they add organic matter to help form soil
Plants start to grow on the soil

6. Secondary Succession

7. Secondary Succession
A disturbance of some kind changes an existing community without removing the soil
Examples:
Fire (lightening strike)
Land cleared for farming

8. Aquatic Succession

9. Succession’s Impact on…
POPULATIONS
As an ecosystem changes, older inhabitants gradually die out and new organisms move in.
SPECIES DIVERSITY
As more species move into as area, more “niches” are created to be filled.

10. Environmental Change
Anything that causes something to be different in an environment
Ex. Temperature increase or decrease; Pollution by humans

11. Ecosystem Stability
Occurs when very little changes happen that can cause ecosystems to be disrupted or made unrecognizable
Ex. No Flooding; No Drought
Google Images Website: telegraph.co.uk

12. Ecosystem Stability Depends on the Environment and Available Resources
Characteristics include… Large diversity, Plenty of resources, and No interruptions
Google Images Website: environment.yale.edu
Google Images Website: soilquality.org

13. OUT: Describe how the 2011 Texas drought caused environmental change
OUT: Describe how the 2011 Texas drought caused environmental change. Explain how the drought impacted ecosystem stability.
Lake Travis, Austin