1. Starter What changes do you think will happen to the following areas within an ecosystem during succession? What changes do you think will happen to the following areas within an ecosystem during succession? Size of organisms Size of organisms Energy flow Energy flow Soil Soil Biodiversity Biodiversity NPP and GPP NPP and GPP

2. Changes in succession You should all be able to: Identify changes in energy flow, gross and net productivity, diversity and mineral cycling at different stages of succession. Identify changes in energy flow, gross and net productivity, diversity and mineral cycling at different stages of succession. Identify different types of climax community Identify different types of climax community Most of you should be able to: Explain why these changes are happening. Explain why these changes are happening.

3. Complete the table As we go through the different factors complete the table with the changes that happen during succession. As we go through the different factors complete the table with the changes that happen during succession. Start now by filling in the “types of vegetation” section in your groups. Start now by filling in the “types of vegetation” section in your groups.

4. Productivity Describe what is happening in this graph…

5. Productivity During early stages gross productivity is because of initial conditions and low density of producers. During early stages gross productivity is because of initial conditions and low density of producers. The proportion of energy lost through respiration is relatively The proportion of energy lost through respiration is relatively So net productivity is So net productivity is In middle stages gross productivity may be In middle stages gross productivity may be In later stages, GPP as climax community reaches maturity In later stages, GPP as climax community reaches maturity Respiration rates are so net productivity is Respiration rates are so net productivity is

6. Productivity Early Stage Middle Stage Late Stage Low GPP NPP is a high percentage of GPP – low respiration Little increase in biomass Gross Productivity high– increased photosynthesis Increases in biomass as plant forms become bigger Trees reach their maximum size Ratio of GPP to R is roughly equal NPP low What’s GPP and NPP?

7. Gross Primary Productivity is low but Net Primary Productivity is a large proportion of GPP because little biomass means respiration is low. NPP as a percentage of GPP falls because respiration rates increase with more biomass

8. Biodiversity What do you think will happen to biodiversity as succession occurs? Why?

9. Mineral cycling At the beginning of succession there are fewer nutrients within the community. Most of these nutrients are held within the soil. Through the process of succession the level of nutrients within the community increases. Most of these nutrients are held within the vegetation.

10. Now complete any missing sections in your table…

11. Disturbance In pairs try to think of possible disturbances that could cause these set backs…

12. Checking outcomes Cut out the pictures and stick them down to create a diagram showing the process of succession. Identify the different stages of succession and label your diagram Annotate how each of the following aspects change through succession: Size of organisms Size of organisms Energy flow Energy flow Gross and net productivity Gross and net productivity Biodiversity Biodiversity Mineral cycling / soil Mineral cycling / soil Now add an explanation for why each of these aspects changes through succession.