Question

Phosphate containing fertilisers cause water pollution. Addition of such compounds in water bodies causes:

(i) enhanced growth of algae.

(ii) decrease in amount of dissolved oxygen in water.

(iii) deposition of calcium phosphate.

(iv) increase in fish population.

Answer 1

(i) enhanced growth of algae.

(ii) decrease in amount of dissolved oxygen in water.

Explanation:

Fertilizers containing phosphate present in water help in the excessive growth of aquatic plants and algae. Micro-organisms which decompose these plants consume oxygen. As a result, the amount of dissolved oxygen in the water decreases.