Today, at the faculty, I presented the topic: "Eutrophication, causes and consequences".
What I can briefly tell you is that eutrophication is a process in which a greater number of organic matter is introduced into aquatic ecosystems, resulting in a blossoming of water. Then the number of algae increases a lot, the water becomes green, and aquatic organisms die.
http://svet-biologije.com/zanimljivosti/zanimljivosti-iz-mikrobiologije/cvetanje-vode/
How does the amount of pollution come from?
From agriculture, from agricultural fertilizers, from the factory, thermal water, communal water, but it can also be a natural process.
https://www.flickr.com/photos/43271721@N07/4120996336
In order to prevent the process, it must act at the very source of the problem, by reducing the amount of organic matter. The processing process consists of several stages where the first includes filters, the second phase is the decomposition of matter and the third chemical processing that is rarely used because it is expensive.
https://ca.m.wikipedia.org/wiki/Filtre_de_sorra
After processing of water through these three phases, are-active life in aquatic ecosystems can occur.
As you would not want someone to endanger your survival, aquatic organisms would not want to find themselves in the same situation.
Think about it.