1. Ecological Succession
Small Trees
Large Trees
Soil
Grass
Shrubs
In this presentation you will:
explore the role of ecological succession
Next >

2. Wild fire news Notice how fast the fire spreads
What is going to happen to the area after the fire has burnt everything?

3. As a group you will need to predict what will happen after the following events. Write down your predictions on the left page
A field after a flood

4. What will this look like in a few months after this mudslide?

5. What will this region look like in 10 years after this eruption?

6. Introduction
Ecological Succession is a gradual, predictable change to the plants and animals in an ecosystem.
It is the process by which an area that is completely bare of any vegetation could eventually become a forest.
Next >

7. Abrupt Changes
Sometimes an abrupt change can occur, that can cause a drastic change to an ecosystem.
For example forest fires, floods, wind storms and volcanic eruptions.
Events such as these can destroy whole ecosystems and leave the earth bare.
Next >

8. Ecological Succession
The biotic (living) and abiotic (non-living) factors of an ecosystem work together in equilibrium (balance).
The process of ecological succession can repair damaged ecosystems to restore this equilibrium and enable life to thrive again.
Succession can be primary or secondary.
Next >

9. Question 1
“Succession refers to the progressive, predictable and long term changes to an ecosystem.”
Is this statement true or false?
Answer true or false.
Next >

10. Question 1
“Succession refers to the progressive, predictable and long term changes to an ecosystem.”
Is this statement true or false?
Answer true or false.
True
Next >

11. Primary Succession
Primary succession is the introduction of organisms into an area not inhabited by any organisms.
For example bare rock, lava after a volcanic eruption or a sand dune.
Next >

12. Primary Succession
Bare rock will first be colonized by a pioneer species that is able to tolerate hostile conditions and make its own food.
Lichen is often the pioneer species.
They produce acids that help to break rock surfaces into small pieces.
Lichen
This helps to create the first soils.
Next >

13. Stages of Succession
Over many years, the soil gets deeper and mosses grow.
As they die, their nutrients are added to the soil and so the soil improves.
Grasses replace mosses.
Small Trees
Large Trees
Soil
Grass
Shrubs
As succession progresses, conditions in the habitat change and become less suitable for some species but more suitable for others.
Next >

14. Stages of Succession
These species thrive and become the next dominant species.
This continues with the dominant species being replaced at each stage. After hundreds of years the soil is deep enough and rich enough to support a woodland.
Small Trees
Large Trees
Soil
Grass
Shrubs
This community remains relatively unchanged and is called the climax community.
Next >

15. Question 2
An area of woodland had once been bare rock. During the process of succession, what would have been the first species to inhabit the area?
A) Lichen
B) Grass
C) Shrubs
D) Large trees
Next >

16. Question 2
An area of woodland had once been bare rock. During the process of succession, what would have been the first species to inhabit the area?
A) Lichen
B) Grass
C) Shrubs
D) Large trees
Next >

17. Secondary Succession
An event like a fire may seem to destroy an ecosystem, but dead organic matter and any surviving organisms could be the beginning of a new community.
The new community would change through time until it reached its climax community once more.
This is secondary succession.
Next >

18. Importance of Succession
Ecosystems are constantly changing.
Fires, floods and volcanoes frequently occur all over the world.
Without succession, a disturbed ecosystem would never recover.
What would our world be like if ecosystems could never recover?
Next >

19. Question 3
Consider a lawn that is constantly being mown. Why does it never reach the climax community stage?
A) Succession is interrupted each time it is mown
B) Plants cannot grow where grass grows
C) Both of these
Next >

20. Question 3
Consider a lawn that is constantly being mown. Why does it never reach the climax community stage?
A) Succession is interrupted each time it is mown
B) Plants cannot grow where grass grows
C) Both of these
Next >

21. Observing Succession
Succession is not limited to large areas, but occurs all around us.
A garden cleared of vegetation and a concreted area both have the potential to turn into a woodland.
You could see this for yourself by observing a cleared area of a garden.
Next >

22. Question 4 What type of succession does the investigation represent?
A) Primary succession
B) Secondary succession
Next >

23. Question 4 What type of succession does the investigation represent?
A) Primary succession
B) Secondary succession
Next >

24. Question 5
Which of the following is not true about ecological succession?
A) A parking lot could eventually become woodland
B) It enables disturbed or damaged ecosystems to repair themselves.
C) Succession results in a stable community called the climax community.
D) The first dominant species will remain throughout all stages of succession.
Next >

25. Question 5
Which of the following is not true about ecological succession?
A) A parking lot could eventually become woodland
B) It enables disturbed or damaged ecosystems to repair themselves.
C) Succession results in a stable community called the climax community.
D) The first dominant species will remain throughout all stages of succession.
Next >

26. Summary In this presentation you have seen:
the role of ecological succession
End >