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Therefore, human causes of eutrophication include the use of agricultural fertilizers. Other causes include sewage and aquaculture, which is the growing or farming of fish, shellfish and aquatic plants. Wastewater from certain industries and burning fossil fuels can also contribute to eutrophication.
Sodium triphosphate, once a component of many detergents, was a major contributor to eutrophication. 1. Excess nutrients are applied to the soil. 2. Some nutrients leach into the soil where they can remain for years.