Question

What is an algal bloom and what causes it?

Answer 1

Algal bloom:

1. The rapid growth of algae in the marine and freshwater due to the addition of various fertilizers usually rich in nitrogen and phosphorus that enhance the growth of algae in the water is called an algal bloom.
2. An algal bloom is caused by the addition of domestic sewage waste into the water bodies which makes the water nutrient-rich and supports the growth of plants.
3. Algae use up the dissolved oxygen and create a thick film on the surface of the water body thereby blocking any sunlight to penetrate through.
4. As a result, the aquatic organisms are devoid of oxygen and photosynthetic plants are unable to liberate oxygen due to paucity of sunlight.
5. Eventually, the entire water body dies.