Monday Sept 16/Tuesday Sept 17 AGENDA Stamp and review homework Notes: Ecological Succession Activity: Ecological Succession & Environmental Change (pg 94-97) Work on Test Review Homework Complete Test Review TEST NEXT CLASS OVER: Lab Safety, Characteristics of Living Things, Levels of Organization, the Microscope, and Ecology

Ecological Succession A series of predictable changes that occurs in a community over time.

Change Ecosystems are constantly changing in response to natural and human disturbances Can you think of any examples?

Ecological Succession As an ecosystem changes, older inhabitants gradually die out and new organisms move in, causing further changes in the community

Primary Succession On land, succession that occurs on surfaces where no soil exists is called primary succession Example: Volcanic eruptions Glaciers receding First species to populate the area = Pioneer species

Primary Succession THE STEPS IN 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

Pioneer species – first species/organisms to inhabit an area (usually small – example weeds) Climax community – stable, mature community that undergoes little or no succession Biome – large group of ecosystems with the same climax community (determined by climate)

Bare rock → lichen → soil with small plants (weeds, mosses, grass) → larger plants (shrubs) → trees

Secondary succession changes that occur when a community is disrupted by natural disaster or humans. Leads to new climax community. Starts from soil → small plants → large plants Examples – fire, flood, hurricane, abandoned farm

Secondary Succession

Aquatic ecosystems – will “fill in” with dirt over time to create a land ecosystem – if no manmade intervention primary succession.