Navigation Links
Researchers predict record Gulf of Mexico 'dead zone' due to Mississippi River flooding

ANN ARBOR, Mich.---Extreme flooding of the Mississippi River this spring is expected to result in the largest Gulf of Mexico "dead zone" on record, according to a University of Michigan aquatic ecologist and his colleagues.

The 2011 forecast, released today by the U.S. National Oceanic and Atmospheric Administration (NOAA), calls for a Gulf dead zone of between 8,500 and 9,421 square miles, an area roughly the size of New Hampshire.

The most likely 2011 scenario, according to U-M's Donald Scavia, is a Gulf dead zone of at least 8,500 square miles, surpassing the current record of 8,400 square miles, set in 2002. The average over the past five years is about 6,000 square miles.

"Stream flows were nearly double normal during May, delivering massive amounts of nutrients to the Gulf, and that's what drives the dead zone," said Scavia, Special Counsel to the U-M President for Sustainability, director of the Graham Sustainability Institute, and a professor at the School of Natural Resources and Environment.

Farmland runoff containing fertilizers and livestock waste---some of it from as far away as the Corn Belt---is the main source of the nitrogen and phosphorus that cause the annual Gulf of Mexico oxygen-starved, or hypoxic, zone. Each year in late spring and summer, these nutrients flow down the Mississippi River and into the Gulf, fueling explosive algae blooms there.

When the algae die and sink, bottom-dwelling bacteria decompose the organic matter, consuming oxygen in the process. The result is an oxygen-starved region in bottom and near-bottom waters: the dead zone.

This year, stream-flow rates in the Mississippi and Atchafalaya Rivers were nearly double normal during May 2011, significantly increasing the amount of nitrogen and phosphorus transported by the rivers into the Gulf.

According to U.S. Geological Survey estimates, 164,000 metric tons of nitrogen were transported in May 2011 to the northern Gulf, off the Louisiana coast. The amount of nitrogen transported to the Gulf in May 2011was 35 percent higher than average May nitrogen loads estimated in the last 32 years.

The amount of nitrogen entering the Gulf each spring has increased about 300 percent since the 1960s, mainly due to increased agricultural runoff, Scavia said.

"Yes, the floodwaters really matter, but the fact that there's so much more nitrogen in the system now than there was back in the '60s is the real issue," he said. Scavia's computer model suggests that if today's floods contained the level of nitrogen from the last comparable flood, in 1973, the predicted dead zone would be 5,800 square miles rather than 8,500.

"The growth of these dead zones is an ecological time bomb," Scavia said. "Without determined local, regional and national efforts to control them, we are putting major fisheries at risk." The Gulf of Mexico/Mississippi River Watershed Nutrient Task Force has set the goal of reducing the size of the dead zone to about 1,900 square miles.

In 2009, the dockside value of commercial fisheries in the Gulf was $629 million. Nearly 3 million recreational fishers further contributed more than $1 billion to the Gulf economy, taking 22 million fishing trips.

The Gulf hypoxia research team is supported by NOAA's Center for Sponsored Coastal Ocean Research and includes scientists from the University of Michigan, Louisiana State University and the Louisiana Universities Marine Consortium. NOAA has funded investigations and forecast development for the dead zone in the Gulf of Mexico since 1990.

"While there is some uncertainty regarding the size, position and timing of this year's hypoxic zone in the Gulf, the forecast models are in overall agreement that hypoxia will be larger than we have typically seen in recent years," said NOAA Administrator Jane Lubchenco.

The actual size of the 2011 Gulf hypoxic zone will be announced following a NOAA-supported monitoring survey led by the Louisiana Universities Marine Consortium between July 25 and Aug. 2.


Contact: Jim Erickson
University of Michigan

Related biology news :

1. Researchers identify why dopamine replacement therapy has a paradoxical effect on cognition
2. Researchers improve method for finding genetic mistakes that fuel cancer
3. Johns Hopkins researchers link cell division and oxygen levels
4. U-M researchers find potential new way to fight sepsis
5. Penn researchers show new evidence of genetic arms race against malaria
6. Penn researchers develop biological circuit components, new microscope technique for measuring them
7. Researchers discover potential cause of chronic painful skin
8. University of Iowa researchers identify caffeine-consuming bacterium
9. USC researchers discover genetic mutation causing excessive hair growth
10. Eating dirt can be good for the belly, researchers find
11. Caltech researchers build largest biochemical circuit out of small synthetic DNA molecules
Post Your Comments:
(Date:6/15/2016)... , June 15, 2016 ... market report titled "Gesture Recognition Market by Application Market - Global ... 2016 - 2024". According to the report, the  global ... billion in 2015 and is estimated to grow ... 48.56 billion by 2024.  Increasing application ...
(Date:6/2/2016)... 2, 2016 The Department of Transport ... the 44 million US Dollar project, for the , ... including Personalization, Enrolment, and IT Infrastructure , to ... production and implementation of Identity Management Solutions. Numerous renowned international ... Decatur was selected for the most compliant ...
(Date:5/20/2016)... MINNEAPOLIS , May 20, 2016  VoiceIt ... technology partnership with VoicePass. By working ... user experience.  Because VoiceIt and VoicePass take slightly ... two engines increases both security and usability. ... expressed excitement about this new partnership. ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... June 27, 2016   Ginkgo Bioworks , a ... engineering, was today awarded as one of the ... the world,s most innovative companies. Ginkgo Bioworks is ... the real world in the nutrition, health and ... directly with customers including Fortune 500 companies to ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... Researchers at ... most commonly-identified miRNAs in people with peritoneal or pleural mesothelioma. Their findings are the ... read it now. , Diagnostic biomarkers are signposts in the blood, lung fluid ...
(Date:6/23/2016)... , June 23, 2016 /PRNewswire/ - FACIT has ... Ontario biotechnology company, Propellon Therapeutics Inc. ... and commercialization of a portfolio of first-in-class WDR5 ... targets such as WDR5 represent an exciting class ... in precision medicine for cancer patients. Substantial advances ...
(Date:6/23/2016)... SANTA MONICA, Calif. , June 23, 2016  The Prostate Cancer ... to pioneer increasingly precise treatments and faster cures for prostate cancer. Members of ... 77 institutions across 15 countries. Read More About the ... ... ...
Breaking Biology Technology: