Question

Explain eutrophication with reference to an aquatic ecosystem.

Answer 1

Eutrophication is the nutrient enrichment of aquatic ecosystems (e.g., lakes and ponds) by sewage, fertilizers, and effluents, resulting in excessive algal (particularly cyanobacterial) blooms. Their decay increases BOD and depletes dissolved oxygen, thereby killing fish and plants and disrupting food chains. Human (cultural) eutrophication is accelerated by pollution; wastewater treatment reduces it.