Nitrogen and phosphorus are fertilisers that cause eutrophication of surface water ... This can lead to excessive algae growth, causing the disappearance of aquatic plants and certain fish species.

Eutrophication is a leading cause of impairment of many freshwater and coastal marine ecosystems in the world. Why should we worry about eutrophication and how is this problem managed ...

from fertilisers are flushed from the land into rivers by rainwater. Oxygen levels reach such a low point that fish and other organisms suffocate. These nutrients cause increased aquatic plant ...