State helps ‘dead zone’ grow
By Philip Brasher and Pamela BroganOzarks Local News, News-Leader.com, Springfield, MO; February 11, 2008
http://www.news-leader.com/apps/pbcs.dll/article?AID=/20080211/NEWS01/802110374/1007/NEWS01
Study:
Washington — Fertilizer from Missouri’s corn boom and waste from livestock are major sources of pollution contributing to a "dead zone" the size of New Jersey in the Gulf of Mexico, a government study says.
The study by the U.S. Geological Survey released last week also said that manure runoff from pasture and rangelands is a much bigger pollution problem than previously thought.
Missouri and eight other Midwestern and Southern states are responsible for more than 75 percent of the nitrogen and phosphorus that reach the gulf, the study said.
Nitrogen and phosphorus encourage the growth of algae in the gulf. When the algae die and sink to the bottom, the bacteria that decompose it suck most of the oxygen out of the water. Shrimp, fish and other marine life must leave the area or die.
Scientists worry that the production of biofuels, such as ethanol produced from corn, will make the problem worse as farmers plant more corn and use more nitrogen fertilizer to meet demand.
Missouri farmers planted 3.5 million acres of corn last year, a 30 percent increase over 2006 and the highest level since 1960, according to the U.S. Department of Agriculture
"The ethanol boom is not helping us," said Kathleen Logan Smith, executive director of the Missouri Coalition for the Environment.
Missouri is the second highest source of phosphorus after Illinois, and the fourth source of nitrogen among states that pollute the gulf, the U.S. Geological Survey study found.
The study is based on computer modeling of land use and water flows. That modeling, in turn, was based on data from a 1992 agricultural census.
Critics say the study is flawed because it is not based directly on data.
"This is seriously flawed because it is based on a model, or somebody’s best guess, rather than real data and facts," said Doyle Childers, director of the Missouri Department of Natural Resources.
Childers also said he doubts the study’s finding that phosphorus runoff from pastures was a significant pollution problem.
The study found that 37 percent of phosphorus runoff into the gulf comes from animal manure on pasture and rangelands, compared to 43 percent from fertilized crops.
"I can’t comprehend that," Childers said. He added that pollution from fertilized lawns and sewage plants might pose a more serious problem.
Childers also disputed the study’s finding that about 9 percent to 12 percent of the nitrogen and phosphorus delivered to the gulf comes from urban sources versus more than 70 percent from agricultural sources.
Childers said Missouri has an "aggressive soil and water conservation" program.
Judy Grundler, director of the plant industry division at the Missouri Department of Agriculture, said the state has received two grants totaling about $200,000 from the Environmental Protection Agency to teach farmers nutrient management practices that reduce pollution runoff.
The pollution travels to the gulf from the Missouri River that flows into the Mississippi River.
In Southwest Missouri, pollution from chicken and livestock waste flow into the Arkansas River, which feeds into the Mississippi before reaching the gulf, Smith said.
The U.S. Geological Survey study said Missouri, Indiana, Illinois, Iowa, Arkansas, Kentucky, Tennessee, Ohio and Mississippi represent just one-third of the land drained by the Mississippi River or its tributaries but contribute more than 75 percent of the nitrogen and phosphorus going into the gulf.
Nitrogen fertilizer on corn and soybeans is the largest source of nitrogen in the gulf, the study said.
Animal manure on pastureland and rangeland and phosphorus fertilizer on crops are the largest contributors of phosphorus in the gulf.
A task force of federal and state officials is expected to use the findings of the report in its recommendations for shrinking the dead zone.
The study will help the government "cut the size of the dead zone in faster and fairer ways," said Benjamin Grumbles, the Environmental Protection Agency’s assistant administrator for water.
Scientists advising the EPA have recommended the government set targets to reduce nitrogen and phosphorus by 45 percent to cut the size of the dead zone in half.
Missouri environmentalist Smith said the study shows that Congress needs to target land-conservation measures in states where the pollutants originate, and boost funding for conservation programs.