Question

Find out what do the terms algal bloom signify.

Answer 1

Algal bloom refers to an increase in the population of algae or blue-green algae in water, resulting in discoloration of the water body. This causes an increase in the biological oxygen demand (BOD), resulting in the death of fish and other aquatic animals.

Answer 2

The rapid increase in populations of algae and other phytoplankton, in particular cyanobacteria, in water bodies rich in organic matter is called algal bloom. The density of the organisms may be such that it may prevent light from passing to lower depths in the water body. An increase in nitrate levels, a mineral ion necessary for both bacterial and algal growth, is the cause of algal blooms.

The source of increased nitrate may be agricultural fertilizers, which are leached – into water systems from the land, or sewage effluent.