Over-supply of nutrients can cause a condition of hypoxia in water bodies. Discuss the harmful effects of such a condition and ways to avoid it.

Eutrophication is the process in which a water body becomes fully enriched with nutrients primarily phosphates & nitrates runoffs from chemical fertilizers. The excessive growth of algae and plankton in a water body are indicators of this process.� The growth of algae soon covers almost entire surface layer and known as algae bloom.
Harmful effects of Eutrophication:

• Lack of oxygen: It leads to less oxygen in the deep part of the lake that produces harmful toxins. This demolishes aquatic life in the affected areas
• Effect on fisheries and the fishing industry: Fishing which is the backbone of the tourism industry also suffers from a loss of revenues
• Health effects: Humans become seriously ill from eating oysters and other shellfish contaminated with toxins
• Loss of freshwater lakes: It creates a layer of wastes in lakes.�Eventually, the water body is reduced into marsh
• Loss of coral reefs: Loss of coral reefs can occur due to a decrease in water transparency

�Ways to avoid Eutrophication:

• The alteration of excess nutrients
• Physical mixing of the water
• Application of powerful herbicides and algaecides
• Reduction in nitrogen emission from vehicles and power plants
• Avoiding the overuse of fertilizers
• Proper channeling of agricultural wastes

Eutrophication is a leading cause of many fresh waters and coastal marine ecosystems in the world. Human activities have accelerated the process to a larger extent. Management of the Eutrophication process is a complex issue that will require the collective efforts of scientists, policymakers and citizens.

Topics: GS-III: Conservation Environmental Pollution Degradation