Question

Assertion [A]: Eutrophication shows an increase in productivity of water.
Reason [R]: With increasing eutrophication, the diversity of phytoplankton increases.

• A. Both A and R are true and R is the correct explanation for A
• B. Both A and R are true but R is not the correct explanation for A
• C. A is true but R is false
• D. Both A and R are false

Answer 1

The correct option is B Both A and R are true but R is not the correct explanation for A

Eutrophication is the enrichment of an ecosystem with chemical nutrients, typically compounds containing nitrogen, phosphorus, or both. It is a natural state in many lakes and ponds which have rich supply of nutrients. Eutrophication becomes excessive however, when abnormally high amounts of nutrients from sewage, fertilisers, animal waste and detergent enter streams and lakes causing excessive growth or bloom of microorganisms. With increasing eutrophication, the diversity of the phytoplankton community of a lake increases and the lake finally becomes dominated by bluegreen algae.