Scientists expect the Gulf of Mexico’s so-called dead zone to increase to record levels this year due to ethanol use and massive Midwest flooding this season.
The strip, which is located off the Texas and Louisiana coasts, could stretch to an unprecedented 8,800 square miles this year, according to scientists from the U.S. National Oceanic and Atmospheric Administration, Louisiana Universities Marine Consortium and Louisiana State University.
That expectation would put the dead zone at almost the size of New Jersey and nearly double the annual average since 1990 of 4,800 square miles.
The dead zone earned its name from being a dense area of algae fed by farm use of fertilizers like nitrogen and phosphorous, which results in lowered levels of oxygen thus causing marine life to suffer.
This year’s strong increase has been linked to the high demand for biofuels in U.S. motor gasoline supplies. Midwestern farmers who raise corn use nitrogen fertilizer, which eventually make its way into the gulf through the Mississippi River.
“We’re planting an awful lot of corn and soybeans,” said Eugene Turner, a scientist at Louisiana State University. “It rinses off easily when there is a rain.”
These algae settle and decay in the bottom waters of the Gulf, and the bacteria that decompose them gobble up oxygen faster than it can be replenished from the surface, which means lower levels of dissolved oxygen in the water.
Fishermen who rely on the gulf as a source of income will be forced to venture further out into the gulf’s waters to find their catch.
One-third of this year’s U.S. corn crop, or 4 billion bushels, will go to make the alternate fuel ethanol, the U.S. government has projected, compared to 3 billion bushels of the 2007 crop.
U.S. scientists estimate that a record 83,000 tons of phosphorus seeped into the Gulf of Mexico from April through June, up to 85 percent above normal seasonal levels.
“Excess nutrients from the Mississippi River watershed during the spring are the primary human-influenced factor behind the expansion of the dead zone,” said Rob Magnien, director of the NOAA Center for Sponsored Coastal Ocean Research.
Turner said that it is imperative that U.S. farmers plant perennial crops in order to trap rainwater from running into the Gulf of Mexico. He added that new developments would be necessary to invent new breeds of perennial corn plants that can remain in the soil from one planting season to the next.
—
On the Net:
Comments