Question

How do water pollution causes eutrophication .
b) List two activities of man which lead to environment pollution.

Answer 1

Natural or artificial substances such as phosphates, fertilisers, detergents, sewage etc causes increase in number of phytoplanktons such as algae which causes algal blooms due to increase in nutrients, which in turn decreases the oxygen supply to the aquatic animals and thus affecting their survival.
Activities which leads to environment pollution-
1. Discharge of waste without treating it properly.
2. Deforestation.