Dead zone warning

Scientists at a meeting in New Orleans Tuesday warned the dead zone in the Gulf of Mexico will create more problems unless fewer fertilizers are dumped into the Mississippi River. Farm runoff is the leading cause of the high nitrogen and phosphorous levels in the Gulf, and the increase in corn growing to meet new ethanol standards in gasoline will keep nitrogen levels high, scientists said. Researchers who mapped the dead zone, where oxygen levels are too low to support most marine life, found the size this year above average, 6,765 square miles, nowhere near the 9,400 square miles some had predicted due to spring flooding in the Midwest. Scientists have been measuring the dead zone since 1985, and this year's cruise found the dead zone was the 11th-largest. But substantial portions of the affected Gulf weren't just low in oxygen, but virtually devoid of it from the surface to the seafloor. (Sources: New York Times, AP via Sun Herald, 08/01/11, Science News, AP via The Republic, 08/02/11)