Biology AQA Past Paper (2015) - Topic 7. Ecology: What is eutrophication?

Eutrophication is an enrichment of water by nutrient salts that causes structural changes to the ecosystem such as: increased production of algae and aquatic plants (algal blooms), depletion of fish species, general deterioration of water quality and other effects that reduce and preclude use. In most cases is caused by the surface run-off of pesticides and fertilizers (agriculture development) into lakes and other non-running waters.

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