Nitrogen Pollution Threat to Mariculture and Other Aquatic Ecosystems: An Overview

In the back few decades, there has been a great increase in costal eutrophication across the globe resulting in hypoxia and anoxia, degradation of habitat, food-web modifications, and biodiversity loss due to the unregulated inputs of nitrogen to mariculture bodies. Before the 1850 and 1950 decades, before the industrial and green revolution, the rate of nitrogen supply on the Earth was limited to the bacterial nitrogen fixation rate but human deeds have adversely doubled the rate of the making of reactive, biologically available nitrogen on the Earth's landmass and which is being supplied in an uncontrolled way to the mariculture bodies causing the threat to mariculture by eutrophication. The artistic eutrophication of the coastal marine ecosystem has the potential to cause toxicological and ecological effects to the proliferation of primary producers either directly or indirectly. The depletion of the level of dissolved oxygen has the potential to the manufacturing of the reduced compounds, like hydrogen sulfide, further resulting in higher adverse toxic effects on aquatic animals. Various inorganic nitrogenous compounds like NH4+, NH3, NO2−, HNO2, NO3− can be produced which can be taken up by the aquatic animals directly from the ambient water out of which ammonia (unionized) is highly toxic, while nitrate and ammonium (ions) are the least toxic but have the potential cause adverse effects on other flora and fauna also on humans.