When a nutrient like fertilizer is present in large quantities in a water bodies, plants grow and decay in large numbers because of suffocation of pond that does not leave enough oxygen needed to support life. This type of pollution is called

Eutrophication or dystrophication or hypertrophication, is when a body of water becomes overly enriched with minerals and nutrients which induce excessive growth of algae. This process may result in oxygen depletion of the water body after the bacterial degradation of the algae. One example is an "algal bloom" or great increase of phytoplankton in a pond, lake, river or coastal zone as a response to increased levels of nutrients.