Eutrophication is the conversion of a body of water to a highly productive ecosystem with rapid decomposition and low Oxygen levels.

It doesn’t sound so bad right now, does it. However, the productive organisms are bacteria and small organisms. They are highly productive so they grow in ridiculous amounts and die off. The decomposition of all these dead bodies and waste takes extreme amounts of oxygen from the water. Oxygen is something everything needs to live so biodiversity plummets in these ecosystems.

Notice the overabundance of algae, but little else? An example of Eutrophication. Credit: Yannemann via Flickr
Notice the overabundance of algae, but little else? An example of Eutrophication. Credit: Yannemann via Flickr
What does this have to do with us? Humans cause eutrophication with the overuse of fertilizers for example. Fertilizers are made to make things grow, containing phosphorus and nitrogen. When these nutrients get into the water systems, they cause this massive increase in production.

This occurs in lakes, oceans and other aquatic ecosystems. You may have heard of this phenomenon in relationships to the Ocean, called “dead zones”, so named for the litter of dead organisms the oxygen-deprived (anoxic or hypoxic) water causes.

For more information, read my research paper on Dead Zones in Oceans. (Dead Zones)