Eutrophication - The nutrient level within any water body is determined by the surrounding lands as the inflowing water carries the nutrients along with them. And this nutrient level is subjected to wide variation which in turn causes a corresponding change in the number and kinds of aquatic microflora. This is well studied in the case of algae which are the major primary producers.
Eutrophication can be defined as the comparatively rapid increase in the supply of nutrients, especially nitrogen and phosphorus, which are then maintained at the new high levels and result in an increased growth of algae and therefore other forms dependent upon them.
