DURING HEAVY RAN IN A VILLAGE THE RAIN WATER CARRY EXCESSIVE FERTILISERS TO A POND. HOW WILL IT AFFECT THE FISH POPULATION N THE POND IN THE LONG RUN.
Due to excessive fertilizer in the pond water, a huge growth of blue-green algae will take place. This is known as algal bloom. Algal blooms cut off light from submerged plants. As a result, the submerged plants die. There is drastic decrease in oxygen replenishment inside water which causes organic loading of water. Decreased oxygen level also kills aquatic animals such as fish. This phenomenon of excessive growth of algae in water bodies due to nutrient enrichment is known as eutrophication.