Eutrophication is caused by increased of fertilizers, waste from animal and households, as well as land clearing for agricultural purposes. Because It make the river to increase nutrient. Eutrophication is affect animal in the river that because it make Aquatic ecosystems to change. In the daytime, Dissolve oxygen in water is so high. But on nighttime Dissolve oxygen is very low until to 0. It makes the aquatic animals to die.