SB9g Biodiversity and humans

Question 1

Name the steps for Eutrophication.

Answer 1

1. Fertilisers / sewage ends up in the river.
2. Plants have excess minerals and grow fast.
3. Water turns green because of algal bloom.
4. Algae covers the surface of water blocking sunlight.
5. Light cannot reach bottom plants so do not photosynthesise and die.
6. Plants decompose and bacteria increase in numbers.
7. Bacteria use up oxygen in the water.
8. Fish run out of oxygen and die.