More Natural Grasses, Less Fertilizer Could Help Gulf of Mexico

By applying fertilizers more carefully, restoring wetlands and planting perennial grasses, Midwestern farmers could dramatically reduce the amount of agricultural runoff now contributing to the 5,000-square-mile, low-oxygen "dead zone" in the Gulf of Mexico, according to a new book written by a team of 25 scientists.

The book, "From the Corn Belt to the Gulf" (Nassauer, Santelmann, and Scavia, eds., Resources for the Future Press), details how farmers could reduce the amount of nitrogen flowing into the Gulf of Mexico by 40 percent. Nitrogen-rich fertilizer is used to boost yield on conventional farms; runoff from such farms throughout the Midwest frequently finds its way into the Mississippi River and then flows into the Gulf of Mexico. There, the nitrogen provides a rich food for algae, which consumes oxygen in the water and creates a hypoxic "dead zone" with insufficient oxygen to support fish and other sea life.

The book's authors are urging the U.S. Congress to include agricultural reforms in the soon-to-be-drafted Farm Bill, and to redirect money currently used for corn and other commodity subsidies to more environmentally sustainable farm and conservation practices. The current Farm Bill is scheduled to expire on Sept. 30, and the House Agriculture Committee expects to draft a new version next week.

About 65 percent of the nitrogen now flowing into the Gulf of Mexico comes from Midwestern farms, according to "From the Corn Belt." Most of that runoff comes from nine states: Minnesota, Iowa, Illinois, Missouri, Indiana, Ohio, Nebraska, South Dakota and Kentucky. Furthermore, five watersheds in three states -- Ohio, Illinois and Iowa -- account for far more nitrogen than any other area.

"While Corn Belt watersheds account for less than nine percent of the land that drains into the Mississippi, land in these watersheds contributes about one-third of the nitrogen reaching the Gulf," said Don Scavia, a University of Michigan scientist and one of the book's editors.