Question

Explain the consequences of eutrophication on the life of plants and animals in an aquatic ecosystem.

Answer 1

1. Nutrient enrichment causes excessive growth of algae, especially blue-green algae, leading to the formation of dense algal blooms or scums on the water surface.
2. These algal blooms release toxic substances harmful to aquatic animals.
3. Decomposition of dead algae consumes dissolved oxygen in the water, causing oxygen depletion (hypoxia).
4. Low oxygen levels lead to the death of aquatic animals like fish and disturb plant life.
5. The aquatic environment becomes rich in CO₂ but poor in oxygen, turning clean water bodies into stinking, uninhabitable conditions.
6. The food chain is disrupted as plants and animals die or become scarce.
7. Cyanobacteria growth increases, some of which can produce toxins further harming aquatic life.