Shades Of Stephen King: Gulf’s Dead Zone GrowingBy Neil Johnson
The Tampa Tribune; June 14, 2008
If the prediction is true, the Dead Zone – an area off the
The increase of possibly 1,700 square miles over the 2007 Dead Zone partly can be attributed to more acreage devoted to corn production.
"That’s an inescapable conclusion," said R. Eugene Turner,
And flooding in the
This Dead Zone forms when nutrient-laden water from the
The decaying algae extract nearly all available oxygen in the water, a condition called hypoxia.
The nutrients mainly come from fertilizers carried in runoff from the vast farming areas of the Midwest that drain into the
This year, the team of scientists says the nutrient level will be 37 percent higher than in 2007. That would be the largest injection of nutrients into the Gulf since measurements began in 1970.
The increase in corn crops for ethanol production worsens the problem because it requires more fertilizer per acre than crops such as soy beans and more of the fertilizer ends up in the rivers, the report states.
In 2007, scientists predicted the increase in acreage devoted to corn would cause the Dead Zone to expand.
Turner said 40 percent of the fertilizer applied in the river’s watershed goes to corn, and corn production increased by 20 percent this year.
Farmers in the Midwest had applied fertilizer to much of the acreage flooded and those nutrients will wind up in the
Fish and shrimp usually are mobile enough to swim out of a dead zone. Animals that live on the bottom such as starfish, crabs and worms can’t escape, and they die.
Decomposing algae uses more oxygen than can be replenished at the surface.
The same condition exists in other places, but the Gulf’s Dead Zone is the second-largest in the world, the National Oceanic and Atmospheric Administration said.
The largest is in the
The Dead Zone normally stretches over the continental shelf parallel to the coast of
The Dead Zone begins forming in the spring and generally peaks about July and lasts into the fall.
Hurricanes could disrupt the process by mixing the water and pushing oxygen toward the bottom where dissolved oxygen levels are at their lowest.Reporter Neil Johnson can be reached at (813) 259-7731 or firstname.lastname@example.org.