Algae microorganisms in the water over populate overpopulate because of the nutrientsurplus nitrogen.The algae take much of the oxygen from the water.Fish and other ogrnizames organisms die.

• 例如，墨西哥湾因为氮肥过量水藻大量繁殖，而且夺取了水中大量的氧气，以至鱼类及其他生物大量死亡。