How do you say "eutrophication" in french??

In french class today we had a discussion about "hyperconsommation", pollution and depletion of natural resources.  Somehow I ended up trying to explain to the class in french how fertilizer used on farms in the midwest has resulted in eutrophication and a Dead Zone in the Gulf of Mexico!  I really need to expand my vocabulary...algae, nitrogen, phosphorus, fertilizers, shellfish and fishing economy are not words one normally encounters in a french class!