Why is the runoff from fertilized agricultural fields,even if free of pesticides,often harmful to the ecosystems of temperate lakes?

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Quizplus · Accepted Answer

Runoff from fertilized agricultural fields contains excess nutrients, such as nitrogen and phosphorus, which promote the growth of algae in lakes. As this algae eventually dies and decomposes, it depletes oxygen levels in the water, causing harm to aquatic organisms. This process is known as eutrophication, which can lead to algal blooms, fish kills, and other harmful impacts on the ecosystem.

Why Is the Runoff from Fertilized Agricultural Fields,even If Free