Pollution management - recall

1. Pollution management - recall In pairs – write down… • What were the three levels of pollution process that we saw when looking at pollution management? • HINT. Remember the diagram that we saw! • Can you remember the example strategies that we proposed at each level?

2. Learning outcomes All of you will be able to: • List different pollution management strategies for eutrophication Most of you should be able to: • Use the pollution management model when identifying the different strategies Some of you might be able to: • Evaluate the different strategies using the pollution management model that we have seen

3. Group work • Based on what you know about the process of eutrophication come up with some possible management strategies. • HINT: use your pollution management diagram to help you!

4. Management of eutrophication Read these different management strategies and decide where to put them in your table… Do not plough up grass as this releases nitrogen. Divert or treat sewage waste. Avoid using fertilisers between mid-September and mid-February when soils are wet and fertiliser is most likely to be washed through soils. Minimise fertiliser dosage on agricultural lands or use organic matter instead. Remove fish to allow primary consumer species to recover and control algal growth. Re-introduce fish later. Remove excess weeds physically or by herbicides and algicides. Phosphate stripping - run effluent into a tank and dose with a precipitant, which combines with phosphate in solution to create a solid. Dredge sediments with high nutrient levels from the river and lake beds. Ban or limit detergents containing phosphate (it is there to improve the performance of the detergent in hard water areas).

5. Management of eutrophication Do not plough up grass as this releases nitrogen. Avoid using fertilisers between mid-September and mid-February when soils are wet and fertiliser is most likely to be washed through soils. Ban or limit detergents containing phosphate (it is there to improve the performance of the detergent in hard water areas). Divert or treat sewage waste. Phosphate stripping - run effluent into a tank and dose with a precipitant, which combines with phosphate in solution to create a solid. Remove fish to allow primary consumer species to recover and control algal growth. Re-introduce fish later. Remove excess weeds physically or by herbicides and algicides. Dredge sediments with high nutrient levels from the river and lake beds.

6. In groups… • Analyse the different methods that are being used and decide which you think would be most effective and why? • Based on the different methods what are the advantages of changing human activity or reducing at point of emission over clean-up? Be ready to explain your answers.

7. Student take over… One person is going to come up and summarise what we have seen today. Someone else will come up and question the class on what we have seen today. You now have 5 minutes to prepare your summary and the questions you would ask to the class.

8. Homework Design a leaflet warning farmers how eutrophication occurs and telling them how to prevent / treat it. • Make it attractive • Include elements from each of the three stages so that the farmers have a variety of options depending on the situation of their lake. • Make it user-friendly (take your audience into account) • Include any relevant key terms

9. Practical set up • Groups of 3 / 4 • Set up the practical to test eutrophication and plan who is going to collect the results on a daily basis.