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Some coastal woes begin far inland

Farm runoff creates ‘dead zones’ offshore, but no national authority is tasked to address them.

By Moises Velasquez-ManoffStaff Writer of The Christian Science Monitor / June 24, 2008

Flight for air: Blue crabs, flounders, eels, and stingrays in Mobile Bay, Ala., flee hypoxic zones by congregating in shallower waters near shore that contain more oxygen.



New York

In the early 1970s, Earl “Rusty” Butz, the US secretary of Agriculture, urged American farmers to plant crops “fencerow to fencerow.” “Get big or get out,” he told them. Farm subsidies followed and, as many small farms consolidated into fewer larger ones, the country transitioned into a new era of corporate-dominated agribusiness. With large-scale farming came the large-scale application of man-made fertilizers.

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Around the same time, large algal blooms began appearing with increasing regularity in the shallow, coastal sea at the mouth of the Mississippi. The algae died and sank. As it decomposed, it sucked oxygen from the surrounding water. Areas along the ocean floor became oxygen-depleted, or hypoxic. Oxygen-dependent organisms that were able to, fled. Those that couldn’t, suffocated.

The nation had a new problem, one that underscored how the ocean’s problems can begin 1,000 miles inland: Fertilizer applied throughout the huge Miss­iss­ippi watershed was creating a “dead zone” in the northern Gulf of Mexico. It’s the second-largest such dead zone in the world, after the one in the Baltic Sea.

Scientists understand the causes and have proposed a bevy of possible solutions. A decade ago, state and federal agencies began to coordinate their efforts to address Gulf hypoxia. The effort got off to a strong start, but has since foundered for lack of funds

“It’s the tragedy of the commons,” says Nancy Rabalais, executive director of the Louisiana Universities Marine Consortium in Cocodrie, La. “Things that a farmer doesn’t know about he doesn’t care about.”

Since the widespread adoption of man-made fertilizers in the 1950s – the innovation behind the “green revolution” – fertilizer and pollution runoff has caused hypoxia to increase in many shallow waters. By one estimate, the number of dead zones worldwide has doubled every 10 years since the 1960s, to 170. The US has about 50 hypoxic areas affecting half its estuaries. As developing countries continue to adopt industrial-scale farming methods, many foresee the problem spreading.

The Gulf dead zone has grown steadily, doubling in average size between 1980 and 2000. Scientists expect it to get bigger. More fertilizer than ever is washing down the Mississippi due to the ethanol boom and heavy rains. This year scientists predict a Massachusetts-sized dead zone, nearly 20 percent larger than the previous record of 2002. Chronic hypoxia has completely altered places like Chesa­peake Bay and the Black Sea. No one knows how the Gulf’s hypoxic zone might affect the area’s lucrative fisheries.

“We’re ... playing roulette with the Gulf fisheries,” says Doug Daigle, coordina­tor of the Lower Mississippi River Sub Ba­­sin Committee on Hypoxia in Baton Rouge, La. “The big fear is that we’ll have a crash.… Once that happens, it’s very hard to try to go back and fix it.”