Controlling Hypoxia on the U.S. Louisiana Shelf: Beyond the Nutrient-Centric View



As the Earth's population continues to increase, the projected effects of contaminant loading and human encroachment on biodiversity remain unclear. One area of intense interest is coastal eutrophication and associated hypoxia events (with hypoxia defined as oxygen <2 milligrams per liter = 1.4 milliliters per liter = ˜63 micromoles per cubic decimeter). On average, the Mississippi River discharges to the northern Gulf of Mexico (GOM) 550 cubic kilometers of freshwater and approximately 60–70×109 moles of dissolved inorganic nitrogen per year [Dagg et al., 2004], which contains anthropogenic nitrogen derived primarily from agricultural fertilizer as well as effluent from animal feedlots.