Water Pollution

Question 1

How does sewage cause eutrophication?

Answer 1

As sewage contains phosphates from detergents and nitrates from urine and faeces. It causes eutrophication the same way that fertilisers do

Question 2

Describe how fertilisers pollute the water

Answer 2

1. Fertilisers enter the water adding extra nutrients
2. Extra nutrients cause algae to grow faster which blocks out sunlight
3. Plants can’t photosynthesise
4. Microorganisms that feed on dead plants increase in size and use up the oxygen
5. Organisms that need oxygen die