While the BP oil spill has been labeled the worst environmental
catastrophe in recent U.S. history, a biofuel is contributing to a Gulf
of Mexico "dead zone" the size of New Jersey that scientists say could
be every bit as harmful to the gulf.
Each year, nitrogen used to fertilize corn, about a third of which is
made into ethanol, leaches from Midwest croplands into the Mississippi
River and out into the gulf, where the fertilizer feeds giant algae
blooms. As the algae dies, it settles to the ocean floor and decays,
consuming oxygen and suffocating marine life.
Known as hypoxia, the oxygen depletion kills shrimp, crabs, worms and
anything else that cannot escape. The dead zone has doubled since the
1980s and is expected this year to grow as large as 8,500 square miles
and hug the Gulf Coast from Alabama to Texas.
As to which is worse, the oil spill or the hypoxia, "it's a really
tough call," said Nathaniel Ostrom, a zoologist at Michigan State
University. "There's no real answer to that question."
Some scientists fear the oil spill will worsen the dead zone, because
when oil decomposes, it also consumes oxygen. New government estimates
on Thursday indicated that the BP oil spill had gushed as much as 141
million gallons since an oil-rig explosion and well blowout on April 20
that killed 11 workers.
Corn is biggest culprit
The gulf dead zone is the second-largest in the world, after one in
the Baltic Sea. Scientists say the biggest culprit is industrial-scale
corn production. Corn growers are heavy users of both nitrogen and
pesticides. Vast monocultures of corn and soybeans, both subsidized by
the federal government, have displaced diversified farms and grasslands
throughout the Mississippi Basin.
"The subsidies are driving farmers toward more corn," said Gene
Turner, a zoologist at Louisiana State University. "More nitrate comes
off corn fields than it does off of any other crop by far. And nitrogen
is driving the formation of the dead zone."
The dead zone, he said, is "a symptom of the homogenization of the
landscape. We just have a few crops on what used to have all kinds of
In 2007, Congress passed a renewable fuels standard that requires
ethanol production to triple in the next 12 years. The Department of
Agriculture has just rolled out a plan to meet that goal, including
building ethanol refineries in every state. The Environmental Protection
Agency will decide soon whether to increase the amount of ethanol in
gasoline blends from 10 percent to 15 percent.
A 2008 National Research Council report warned of a "considerable"
increase in damage to the gulf if ethanol production is increased.
Pet cause of Congress
One of the authors of that report, agricultural economist Otto
Doering at Purdue University, said that a 50 percent boost in the
ethanol blend in gasoline will significantly raise corn prices, driving
farmers to pull land out of conservation and pastureland and into corn
production. They are also likely to add more nitrogen fertilizers to
Corn ethanol has been heavily subsidized since the Arab oil embargo
in the 1970s. Viewed by the corn industry as a lucrative market, ethanol
is a perennial favorite in Congress.
Ethanol consumes two-thirds of all federal subsidies for renewable
fuels, said Ken Cook, president of the Environmental Working Group, an
advocacy group, leaving solar, wind and the rest to fight over the
remaining third. Corn ethanol cost taxpayers $17 billion from 2005 to
2009, his group estimates.
"This is another industry that's entirely a creature of the
government, even more so than corn growing per se," Cook said. "The
production of ethanol wouldn't happen at all without government
subsidies and protection."
The National Corn Growers Association ran a media blitz in Washington
last week to press for the renewal of the 51-cents-a-gallon tax credit
for ethanol. With pictures of the BP oil spill looming in the
background, the Corn Growers' video announces, "Ethanol: Now is the
Conservation plan hurt
The ethanol boom over the past decade has lured farmers to withdraw
millions of acres from the Conservation Reserve Program, which pays
farms not to plant fragile land. Much of this land has been returned to
native prairie grasses, at taxpayer expense. Millions more acres are up
for renewal over the next few years.
"There's been a very large-scale conversion of these CRP lands to
biofuel production," Ostrom said. Those soils have accumulated carbon
from the atmosphere and stored it, becoming "a pretty significant sink
for atmospheric CO2," he said. "If we suddenly start farming those
soils, we basically release all of the carbon that's been sequestered
for decades, and that may more than offset any carbon benefit of
switching to biofuels."
To meet its goal of tripling ethanol production, Congress called for
more cellulosic ethanol, which is made from wood, crop waste, perennial
grasses such as switchgrass, and even native prairie grasses. Perennial
grasses are considered far less damaging to the environment than corn
because they require less fertilizer and their roots remain in the
ground, helping to stabilize the soil and reduce runoff.
But commercial production of cellulosic ethanol remains a pipe dream.
It would require large subsidies to dislodge corn ethanol.
There is no experience with commercial production of switchgrass.
Purdue's Doering said it will require fertilizer and is likely to be
planted on conservation lands and pasture instead of displacing corn.
Joan Nassauer, a professor at the University of Michigan who has
studied how alternative agricultural policies could alleviate the dead
zone, said cellulosic ethanol could work.
"It might be one of those win-wins, but it's not in production yet,"
she said. "What we've got now all over the Corn Belt is corn, and that's
definitely not a win-win."