Biofuels push could boost Gulf dead zone

By Amy Wold
The Advocate, Baton Rouge; March 11, 2008

As Congress mandates an increase in biofuel production, a scientific study shows the push for additional corn production could have negative consequences for the Gulf of Mexico‘s health.

Published Monday in the Proceedings of the National Academy of Sciences, the paper shows how increased production of corn for ethanol will put more nutrients into the Mississippi River.

The increase in nutrients will increase the size of the annual low-oxygen "dead zone" area in the Gulf, according to the paper co-authored by Simon Donner, assistant professor at the University of British Columbia‘s Department of Geology, and Chris Kucharik with the University of Wisconsin.

"The pollution (nitrogen) that causes the dead zone would go up 10 to 18 percent" Donner said.

While that may not seem like much, Donner said, a national action plan to reduce the size of the dead zone calls for the need to reduce nitrogen by 30 percent to 55 percent of today’s levels. That was going to be tough enough to meet without adding more nitrogen to the equation, Donner said.

"You’re taking this very difficult challenge and making it impossible," Donner said. "All the science is pointing at that we need to think about it before we leap into these things."

Doug Daigle, hypoxia program director with the Mississippi River Basin Alliance, said corn-based ethanol will definitely be a challenge to reducing the dead zone, but it’s not surprising.

"This is a predictable effect of decisions being made," Daigle said.

There’s been no real investment in reducing the size of the dead zone — also known as hypoxia — but there are subsidies for ethanol production that will eventual worsen it, he said.

The dead zone forms every summer when nitrogen and nutrients from things such as fertilizers flow into the Gulf and help feed the growth of small organisms.

As these organisms die and decompose, they sink and use up oxygen in the lower levels of water.

During the summer, the low-oxygen water layer fails to mix with more oxygen-rich layers near the surface. Oxygen levels in lower layers can get so low that the water can’t support most marine life.

Corn farming uses a lot of fertilizer, which ends up running into waterways that lead to the Mississippi and eventually into the Gulf, Daigle said.

As corn production increases to help meet the 2007 Energy Bill’s goal for ethanol, the amount of nitrogen fertilizer applied will also increase, Donner said.

The federal legislation calls for the nation to produce 36 billion gallons of renewable fuels — 15 billion of which can be from corn-based ethanol — by 2022.

Donner said he and Kucharik wanted to see the impact that much corn production would have on nitrogen levels in the Mississippi.

Using 2004-06 as a baseline and comparing it to corn production growth in 2007, the researchers examined how farmers made decisions on the choice and location of crops.

Based on the comparison, Donner and Kucharik extrapolated that information to see how farmers might make similar decisions in the future to meet the 2022 ethanol goal.