Question

Phosphate pollution is caused by _______.

• A. Weathering of phosphate rocks only
• B. Agriculture fertilizers
• C. Phosphate rocks and sewage
• D. Sewage and agricultural fertilizers

Answer 1

Answer: (D)

Sewage and agricultural fertilizers

Phosphate pollution in the water is directly related to the release of the untreated sewage and agriculture fertilizers into the water body. This results in excessive algal bloom that forms a thick layer on the surface of the water and prevents the sunlight and oxygen from getting into the water. As a result, the underlying aquatic animals and plants suffocate and die. When this algal bloom dies, it further enhances the eutrophication process, greatly decreasing the dissolved oxygen in the water.

Hence, the correct answer is 'Sewage and agricultural fertilizers'.