Mature forest

Forest fire

After a forest fire

• Does it remain empty and dead forever?• What will this area look like in 200 years?• Why?• What aim does this suggest for today?

Aim

• How will a forest recover from a fire that destroys it?

After a forest fire, what is left?

• Soil, dead plant materials• What will happen to the remains?• The remains will be broken down by

decomposers• What effect will it have on the remaining soil?• It will make the soil rich with carbon and

nitrogen, nutrients

First organisms

• Bacteria and fungi (decomposers) and lichen are the first organisms to return to a dead ecosystem

• They are called pioneer organisms.

Describe what you think will happen next

• We have this rich soil with nothing growing.• Will something start to grow? What? Why do

you think this will grow?• Moss and grasses, plants that can grow close

to the ground. • How do the seeds and other plants get to the

burned forest?

What happens next?

• After the grasses, larger plants can grow, such as shrubs

• Then the trees will start to return• In 100-200 years, the forest will look similar to

what it looked like before the fire!• Succession is the return of living organisms to

an environment that does not have life

How does the physical environment affect the living organisms?

• Physical environment determines which organisms can grow and survive

How do the living organisms affect the physical environment?

• Living things can modify the environment.

Ecological Succession

Climax community

• The mature, stable community that returns after ecological succession is climax community

• In this case, the mature forest is the climax community

• What determines what plants make up a climax community?

What determines climax community?

• The physical environment will determine which plants make up a climax community

• For example, a hot, rainy environment will give you a tropic rainforest climax community

• How do you know what animals will live in a climax community?

• The types of plants present

Two types of succession

• Primary succession-when living things start to grow on an area where there was no life before, such as on newly formed lava

• Secondary succession-when living things start to grown on an area that replaces a former living community

• Which type of succession is our forest fire succession? Why?

Another example of succession

• http://library.thinkquest.org/04oct/00228/succession.htm

Succession in a pond

Succession after glacial melting

Have you seen ecological succession happen in New York City?

Do you see any succession happening in your bottle ecosystem?

Homework

• Due tomorrow, Friday• Introduction section of bottle ecosystem lab

report• Reminder: Unit 2, ecology exam on Monday.• If time, take your last observations for your

bottle ecosystems.