Bellwork: Wednesday, Oct 10th

• Grab your supply bins. Get the one that corresponds to the number on your table!

• Complete pg 41 #5 & pg 102 #6

• Pull out your carrying capacity worksheet from yesterday.

Life ScienceLesson 4Changes in Ecosystems

Succession

Definition:

The replacement of one type of community by

another at a single location over a period of

time

PRIMARY SUCCESSION

Definition: A community that starts to grow in an area that has no soil such as •a cooled lava field•bare rock field caused by a retreating glacier

Primary Succession, continued

The 1st organisms to live in the lifeless area are called pioneer species, such as lichens.

In a forest lichens are followed

by mosses, grasses, shrubs,

heath mat, pines, and ending

in hardwoods

PRIMARY SUCCESSION

Lichens secrete acids that break down rocks

Rocks also break down through weathering

Formed from seeds carried inby the wind or animals

Climax Community

PRIMARY SUCCESSION

A climax community is the final step in primary succession

Definition: A communitythat does not undergo further succession

SECONDARY SUCCESSION

• Definition:

A type of succession that occurs in areas that are disturbed, but still have soil

• Example:

A fire or flood

SECONDARY SUCCESSION

• Begins with fast-growing grasses and non-woody plants and then moves step-by-step toward a climax community just as

primary succession

does

SECONDARY SUCCESSION

Climax Community

Intentional Succession

Definition: A type of secondary succession that occurs in areas that are intentionally disturbed

This most often takes place through controlled

burns

Controlled Burn

Controlled burning stimulates the

germination of some desirable forest trees,

thus renewing the forest. Some cones, such

as sequoia require heat from a fire to open

cones to disperse seeds.

Examples

Highbanks Metro Park in Columbus

• Their controlled burn restored the prairie to maintain the bluebird population

ExamplesDing Darling Wildlife Refuge on Florida’s

Sanibel, Island

• The purpose of their burn was to remove unwanted growth, reduce risk of a wildfire, and to promote native natural habitat