Nitrogen and phosphorous
Eutrophication is characterized by excessive plant and algal growth due to the increased availability of one or more limiting growth factors needed for photosynthesis (Schindler 2006), such as sunlight, carbon dioxide, and nutrient fertilizers. Eutrophication is the enrichment of surface waters with plant nutrients. While eutrophication occurs naturally, it is normally associated with anthropogenic sources of nutrients. The trophic status of lakes is the central concept in lake management. It describes the relationship between nutrient status of a lake and the growth of organic matter in the lake. Organic fertilizers. Eutrophication is the enrichment of surface waters with plant nutrients. While eutrophication occurs naturally, it is normally associated with anthropogenic sources of nutrients. The trophic status of lakes is the central concept in lake management. It describes the relationship between nutrient status of a lake and the growth of organic matter in the lake. The nutrients that cause this excessive plant growth are nitrogen, phosphorus and other trace elements. These elements are derived from many sources, the most important of which are domestic waste waters, urban drainage, agricultural sources, the atmosphere, ground water and, to some degree, lake sediments. Confidence votes 34.5K. Eutrophication Eutrophication is a process in which bodies of water (lakes, ponds, and rivers) receive excess nutrients that stimulate excessive growth of algae. The two most common nutrients that initiate eutrophication are nitrogen and phosphorous, two limiting nutrients in the growth of algae. These two nutrients are usually introduced to the body of water through fertilizer run-off. Eutrophication is a noun that refers to the excessive richness of  nutrients in water body or a lake. The excessiveness is due to  frequent runoff from the land that causes … dense growth of plant  life. It can be caused naturally or by human. Given the widespread extent of water quality degradation associated with nutrient enrichment, eutrophication has and continues to pose a serious threat to potable drinking water sources, fisheries, and recreational water bodies.
http://www.nature.com/scitable/knowledge/library/eutrophication-causes-consequences-and-controls-in-aquatic-102364466 http://www.fao.org/docrep/w2598e/w2598e06.htm http://www.fao.org/docrep/w2598e/w2598e06.htm http://www.gfredlee.com/eutroph.html http://www.answers.com/Q/What_is_eutrophication http://www.answers.com/Q/What_is_eutrophication http://www.nature.com/scitable/knowledge/library/eutrophication-causes-consequences-and-controls-in-aquatic-102364466
what nutrient is most associated with eutrophication