West Lafayette, IN -- A study of the cost of proposed changes in nitrogen management needed to eliminate the hypoxic zone, or dead zone, in the Gulf of Mexico has found that the American farm system can afford these changes -- barely.
Scientists estimate that to eliminate the hypoxic zone in the gulf, the United States should reduce the amount of excess nitrogen flowing down the Mississippi River by 20 percent or more, and much of the burden of that reduction would be placed on farmers.
Otto Doering, a professor of agricultural economics at Purdue University, has found that farmers can use a variety of methods to cut the flow of excess nitrogen by 20 percent to 25 percent without hurting food prices or farm exports. "Beyond that, however, American agriculture begins to fall out of bed," Doering says.
The Gulf of Mexico hypoxic zone is a 7,000-square-mile area in the northern gulf that has too little oxygen to support most marine animals (hypoxic means oxygen deprived). The zone begins at the mouth of the Mississippi River and extends west toward the Texas coastline, occurring in the middle of the most important commercial and recreational fishing zone in the lower 48 states.
The zone exists because of the flood of excess nitrogen that comes down the Mississippi River each summer. Nitrogen is an important plant nutrient, and with so much of it in the gulf, small plants such as algae grow so much that they use up the available oxygen in the sea water.
The dead zone doesn't actually kill any fish, because they are able to swim away from the area. Other types of sea life, such as starfish and sea anemones, may not be able to escape and may die.
Although other hypoxic zones exist in the Black Sea, Baltic Sea,
Chesapeake Bay and New York Bight, the Gulf of Mexico is unique.
Because the Gulf of Mexico is open to ocean currents, unlike other enclosed
seas, scientists think that the problem can be
Contact: Steve Tally