Dead zone now smaller after Gustav

By Justin Fritscher
September 12, 2008; Jackson

Hurricane Gustav decreased the size the dead zone, an area of oxygen-depleted water off the Louisiana coast that lacks marine life, a scientist said Friday.

But it’s unclear by how much.

When a large storm moves through a dead zone, it re-aerates the water, thus causing it to shrink. Some of the guages used to measure the dead zone are showing higher oxygen levels, said R. Eugene Turner, a Louisiana State University coastal ecology professor.

Turner said a cruise of scientists was scheduled for early next week, but Hurricane Ike caused it to be postponed.

Hurricane Dolly decreased its size earlier this year, according to a report released by Louisiana Universities Marine Consortium in late July.

“If it were not for Hurricane Dolly, the size of the Dead Zone would have been substantially larger,” said Nancy Rabalais, LUMCON executive director, in the report.

The dead zone forms as substances from farms, such as nitrogen and phosphorous, travel down the Mississippi River or one of its tributaries and into the Gulf.

These fertilizers, which help plants grow on land, cause algae to grow in the water. The algae deplete the oxygen, causing a dead zone at the bottom of the water.

Dead zones disperse what marine life can swim away and kill what can’t.

After a cruise in late July, the dead zone, which was 8,000 square miles and the second largest in history,

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