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

2. 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 >

3. 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. Next > Events such as these can destroy whole ecosystems and leave the earth bare.

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

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

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

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

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

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

10. Stages of Succession Next > This community remains relatively unchanged and is called the climax community. 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. SoilGrassShrubs Small Trees Large Trees

11. 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? Question 2 Next > A)Lichen B)Grass C)Shrubs D)Large trees

12. Question 2 Next > 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

13. 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. Next > The new community would change through time until it reached its climax community once more. This is secondary succession.

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

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

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

17. Observing Succession Succession is not limited to large areas, but occurs all around us. Next > 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.

18. Succession in a Microhabitat In an area of garden that is cleared back to soil, place a series of quadrats in the area and leave them there. Next > If you do not have a quadrat available, you could mark out areas using sticks and string. Quadrat

19. Succession in a Microhabitat Over the next few months, study the quadrats or marked areas on a regular basis. Next > Observe the types of life that begins to form. In a journal make a note of the date and the plants observed. You could also monitor the soil to see if there is any change in the amount of organic matter as the plants grow and die. Quadrat

20. Succession in a Microhabitat A very simple way would be to take a small sample of soil using a graduated cylinder (or a beaker). Next > Add water to the sample and swirl the cylinder to mix the soil and water. Left to settle, the sample will separate and the organic matter will float to the surface. Use the graduations on the side of the cylinder to observe the amount of organic matter.

21. Succession in a Microhabitat Over the next few months, record the types of plants that begin to grow there and how the soil changes. Next > You would probably find that the first plants would be small plants you would consider to be weeds. Eventually these weeds would give way to grasses and then to larger plants. If you left it long enough you would see trees.

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

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

24. Which of the following is not true about ecological succession? Question 5 Next > 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.

25. Which of the following is not true about ecological succession? Question 5 Next > 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.

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