How does fertilizer affect aquatic ecosystems?

Fertilizer ranks toward the top of the list when it comes to pollutants that have harmful effects on aquatic ecosystems by adding chemicals and disrupting ecosystem functions. They do considerable amounts of damage in short periods of time. Fertilizers may impact aquatic ecosystems as point source and nonpoint sources of pollution, but regardless of entry, their effects are profound.

Fertilizers primarily enter aquatic environments in the form of chemicals, primarily nitrogen and phosphorous. However, they may also enter into lakes, streams and other water ecosystems through lawn clippings and raked leaves, which wash into those environments via drains and deposit large volumes of phosphorus.