Some Coastal Woes Begin Far Inland

By Moises Velasquez-Manoff , Christian Science Monitor. Posted June 25, 2008.

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.

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."

The problem, which embraces the 1.2 million-square-mile Mississippi watershed, spread across 31 states, is daunting. But a recent US Geological Survey report indicated that the fertilizer sources are relatively concentrated. Nine states contribute 75 percent of the nutrient runoff that ends up in the Gulf. Each year, $391 million worth of fertilizer washes down the Mississippi, according to the nonprofit Envi°©°©ron°©°©mental Working Group (EWG) in Washington.

Mitigation measures are relatively low-tech. Planting a buffer of certain crops - switch grass, for example - around farmland can cut nutrient-rich runoff. Wetland systems absorb nutrients in the water, which places a premium on wetland restoration. Changing when and how farmers fertilize also lessens runoff.

When polled, farmers say they would prefer the more diverse landscape implied by buffers and restored wetlands. Indeed, various programs exist at both state and federal levels to pay farmers to let land go fallow, or even restore it. But currently the incentives to plant crops -- including direct subsidies and high food prices -- are much greater than those for conservation. In the top polluting counties, EWG puts the ratio at 500 to 1.

"They're being paid to grow more and more corn rather than to implement these conservation measures," says Donald Scavia, professor of natural resources and environment at the University of Michigan, Ann Arbor. "You're concerned about fish in the ocean, and it's being driven by US farm and energy policy."

See more stories tagged with: dead zone, water pollution, farm runoff, pesticides, fertilizer, oceans

Moises Velasquez-Manoff is a staff writer of the Christian Science Monitor.

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