question_answer 4)

Find out what do the term 'algal bloom' and 'red tides' signify?

Answer:

Sometimes, green algae such as Chlorella, Scenedesmus and Spirogyra, etc., grow in excess in water bodies and impart green colour to the water. These are called algal blooms. Red. dinoflagellates (Gonyaulax) grow in abundance in sea and impart red colour to the ocean. This looks like red tides. Both due to algal blooms and 'red tide' the animal life declines due to toxins and deficiency of oxygen inside water.