How do ecosystems change over time?

How do ecosystems change over time?

???

Seuss Forest

Seuss Forest

Seuss Forest

WHAT’S GOING TO HAPPEN IN THE NEXT

100 YRS???

Year 1:Pioneer Plants: Weeds

Seuss Forest Year 2: Shrubs move inYear 1:Pioneer Plants: Weeds

Competition!

Seuss Forest Year 2: Shrubs move inYear 1:Pioneer Plants: Weeds

Year 10: Pine trees dominate

Seuss Forest Year 2: Shrubs move inYear 1:Pioneer Plants: Weeds

Year 10: Pine trees dominate

Year 20: A mixture

Year 100: Maples Dominate

Maple seedlings out compete pine tree seedlings. What will happen over time?

Cleared Field

Pioneer Plants

Pioneer Community

Shrubs begin to grow

Pines 1st dominant community

Maple climax community

From rock to soil? Video Lichens- Every lichen is a partnership usually

between a fungus and an algae. The fungus protects the alga from the harsh world outside, and provides it with water and mineral nutrients. The alga makes its own food by photosynthesis, and leaks some of this food, which is then absorbed by the fungus (which cannot make its own food).

What kind of relationship is this?

Examples Primary Succession: Volcanic islands

• Lichens grow on rocks and break them apart to allow plants to start growing

Page 17

In a natural____________, a series of changes takes place. On a bare field, the ___________ plants grow first. When one type of plant is most numerous, we call it ____________. At the end of a succession, there is a __________ community.

Climax Dominant SuccessionPioneerShrubs

A. In a succession, a pine forest comes ( ) a maple forest

B. When weeds and shrubs compete in a field, the shrubs ( )

C. After ( ) plants are dominant, no more changes occur

Before

WinClimax

Page 16 1.Stage 1 2. Grasshoppers die out after stage one

because the lack of grasses 3. High Trees 4. It shaded them out 5. Short-Tailed Shrew.

Info: The short-tailed shrew digs through the forest litter or tunnels in moist soil, and is active mostly during early morning and late afternoon. Its diet is principally earth-worms, snails, and insects but fungus, various invertebrates, and occasionally small vertebrate animals are also eaten.

Ticket out Put these pictures in successional order (if you

think picture 3 is the first stage, then list it first)

1 2

3 4

Succession

Interactions Change over time

Disturbances

Plant communities, and therefore animal communities, change in an ecosystem over time in response to different disturbances. This change over time is often quite predictable and usually creates a balanced ecosystem through members interacting with each other and their environment

Competition

Facilitation (one makes the environment better for another)

Vary in extent and intensity

Predictable patters

Tolerance

lichens - grass - shrubs - trees

Not necessarily a bad thing

Forest fire, tree fall, glacier movement, flood...

the series of predictable changes that occur in a community over time