Question

In a village in Karnataka, people started cultivating crops all around a lake that was always filled with water. They added fertilizers to their field in order to enhance the yield. Soon they discovered that the waterbody was completely covered with green floating plants and fishes started dying in large numbers. Analyze the situation and give reasons for excessive growth of plants and the death of fish in the lake.

Answer 1

Eutrophication:

1. The green floating plants discovered by the villagers are a result of the process known as eutrophication.
2. The process of algal growth over the surface of a water body, is known as eutrophication.
3. The excessive algal bloom is composed of algae and plankton.
4. This leads to enrichment of the water body due to the plankton and algae.
5. The fertilizers released in the field contain large amount of nitrogen, hence it leads to the growth of algae on water bodies.
6. But this leads to a reduction in the quality of water.
7. It leads to the depletion of dissolved oxygen in the water due to the high growth of algae and plankton, therefore the plants and fishes died in large numbers.
8. The aquatic life of the water is also affected due to the algal bloom.
9. Drinking water is also damaged due to eutrophication.
10. The algal bloom blocks the sunlight from entering the water surface as they cover it up, thus also affecting water plants in the water body.
11. The algal bloom also releases stinking odors from decaying organic matter which cannot be even controlled from chlorination if it is drinking water.
12. Hence, all these reasons show the excessive growth of plants due to eutrophication and the damage it can cause.