Eutriphicaiton comes from the prefix, “Eu” meaning good, and trophic, “meaning tending toward.” In other words, in the natural world eutrophication refers to "good nutrition for algae. " But there is nothing good about eutrophication when it is caused by high concentrations of phosphates and nitrates. That is because high concentrations of these, usually from man made pollution to water ways, results in high growth of that algae. When such high concentrations occur they impact and deplete the oxygen available as it rots. This condition is called Hypoxia.
Too much concentration of these is deadly to organisms in a river, pond, lake or sea, as they are choked out. The decomposition of blooming algae results naturally when the algae has more nutrients than needed for stabilizing growth. The word Hypoxia refers to the diminished levels of oxygen that organisms, both microorganisms and animals need. Eutrophication can be thought of as the smothering agent, and hypoxia, the smothering result. Many fish cannot survive in Hypxoia conditions in waters, which are often off coastal areas and estuaries. So what causes Eutrophication?
Eutrophication is present from two origins, distinguished by point and nonpoint sources. A single point of discharge, such as a large industrial drain point that spews polluted water may commonly contain both nitrates and phosphates. Phosphates are often found in cleaning solutions, fertilizers, detergents and more. Nitrates are also found in farming effluent which contains both natural and artificial fertilizers. Sewage and waste waster treatment plants also contribute a toxic level of nitrates and phosphates to critical water sources, endangering life there, and in the inter-related community.
Non point sources of Eutrophication are harder to control. They come from street and air pollution, households, industrial factories and private companies. Think of them as non pin pointed pollutants, and one can see the challenges facing those who regulate and seek to protect water sources from contamination. Die offs of fish and other organisms can be a major cause of an eventual die off of an entire eco system.
People are completely dependent upon the health of life giving water supplies. People are dependent too, upon just the fish, which are just one aspect of concern for ecosystems. Getting educated about ways to prevent waste and over use of detergents and fertilizers is therefore very critical to protecting human, and all other, life.