WASHINGTON - JUNE 15 - Applying fertilizers with greater precision in combination with other conservation innovations, the restoration of wetlands and the production of perennial crops, such as native grasses for biofuels, could dramatically reduce the 5,000 square mile "dead zone" in the Gulf of Mexico.
Those are the key conclusions of a new book written by 25 leading scientists throughout North America entitled, From the Corn Belt to the Gulf, (Nassauer, Santelmann, and Scavia, eds., Resources for the Future Press). The book authors discussed their agriculture conservation reform proposals at a combined news conference/teleconference today less than two weeks before the House Agriculture Committee is scheduled to draft the Farm Bill on June 26-28.
The book concludes that adoption of best management practices and enterprise innovations by farmers, when combined with wetland and grassland restoration, could reduce the amount of nitrogen reaching the Gulf of Mexico by 40 percent and recommends that agricultural expenditures currently directed toward commodity program payments in the current Farm Bill that expires September 30 be redirected when the Farm Bill is reauthorized this summer to encourage a more effective, comprehensive approach to conservation.
Nitrogen is a component of fertilizer that contributes to low oxygen levels in the Gulf, a condition scientists call "hypoxia" that threatens commercial fisheries. About 65 percent of the nitrogen reaching the Gulf originates from agriculture, according to the book.
The book also concludes that most of the nitrogen reaching the Gulf originates in parts of nine states -- southern Minnesota, Iowa, Illinois, northern Missouri, Indiana, and western Ohio, eastern Nebraska, southeastern South Dakota, and western Kentucky.
"While Corn Belt watersheds account for less than nine percent of the land that drains into the Mississippi, land in these watersheds contribute about one-third of the nitrogen reaching the Gulf," said Don Scavia, a University of Michigan scientist and editor of the book.
In particular, five watersheds in three states -- the Great Miami River watershed in southwestern Ohio; Upper Illinois River watershed in Illinois; and the Des Moines River, Iowa River and Skunk River watersheds in Iowa --contribute far more nitrogen than other parts of the 31-state river basin.
The book reports on scientific assessments of three different future policy scenarios applied to small Iowa watersheds, including one scenario that measures the effects of widespread adoption of both familiar and innovative best management practices by farmers, the restoration of some wetland and upland habitats, and significantly more production of perennial crops like prairie grass. That scenario results in a 300 percent increase in the production of perennial grasses, which could be used for "cellulosic" ethanol and it compares favorably to the other scenarios in its economic returns and water quality results.
"Adopting measures that improve water quality in the Gulf could also improve water quality, reduce flood losses, and provide wildlife habitat from Minnesota to Mississippi," said Scott Faber, Director of Environmental Defense's Healthy Farms, Healthy Food Campaign. "Farmers are eager to share the cost of cleaner water, but two out of three farmers are rejected when they offer to improve Mississippi River water quality due to funding shortfalls. Renewal of farm policies in the 2007 Farm Bill is a chance to reward -- rather than reject -- farmers when they take steps to help rivers like the Mississippi."
The Environmental Protection Agency’s Science Advisory Board is currently reviewing the findings of the Mississippi River Basin and Gulf of Mexico Hypoxia Task Force established by the Clinton Administration.
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