Reviving Gulf of Mexico's "Dead Zone".

• Position: Brief Article

Researchers are studying ways to control the rush of nitrogen and other chemicals that flow into the Mississippi River watershed each spring and ultimately turn more than 7,000 square miles of the Gulf of Mexico into a "dead zone." Nitrogen and other nutrients cause hypoxia, whereby excess nutrients, such as nitrogen and phosphorus, accumulate in a body of water and cause algae to flourish into algal blooms. These blooms thrive on nitrates and phosphates and deplete the water of nearly all dissolved oxygen. Hypoxia in the Gulf stems from human activities in the Mississippi River watershed, which encompasses more than 40% of the U.S.

"The answers to controlling hypoxia essentially come down to using nature to take care of our problems while protecting its biodiversity," explains William Mitsch, professor of natural resources, Ohio State University, Columbus. "These solutions embrace ecotechnology, which...