What does a “record-setting dead zone” mean for Louisiana’s coast?
By Rachel Schott, Mississippi River Delta Restoration Campaign
Dead zone. Words that bring images of military exercises or deserted, war-torn areas of land, but certainly not an acceptable description of a region that contains some of the nation’s most vibrant and diverse ecosystems, wildlife and habitats. Right?
Recent studies released by the National Oceanic and Atmospheric Administration (NOAA) and conducted by Louisiana State University, Louisiana Universities Marine Consortium, and University of Michigan scientists forecast a “record-setting dead zone” for the Gulf of Mexico this summer. The studies suggest that the 2013 dead zone area could be anywhere between 7,286 and 8,561 square miles, which would be substantially larger than last year’s dead zone of almost 2,900 square miles.
According to NOAA, dead zones are not uncommon for waterways and estuaries, as they have recorded 166 dead zones along United States coastlines. As the Gulf of Mexico is at the receiving end of the country’s largest river system, the Mississippi River’s discharge is one of the main causes of the Gulf dead zone. Unfortunately, a dead zone is exactly what it sounds like: an area normally teeming with wildlife and vegetation is infiltrated by pollutants, fertilizer chemicals and industrial runoff. When the river’s more buoyant fresh water enters the Gulf of Mexico, it lies on top of the denser, saltier water, causing a stratification that isolates the deeper waters from receiving a necessary amount of oxygen.
The Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) explains that the influx of these unnatural substances and nutrients results in the overgrowth of algae and marine organisms on the surface of the water. At the end of their life cycle, they sink to the bottom and are decomposed by bacteria, a process that depletes the oxygen supply from the water, making the existence of life nearly impossible. Every type of marine life is affected, from Gulf fish to tiny marine organisms, which are all essential parts of an interdependent ecosystem necessary for maintaining the balance of life in the Gulf of Mexico.
In scientific terms, the low oxygen is known as hypoxia and has severe effects on the future health and growth of ecosystems. TIME Magazine recently reported that the Gulf of Mexico may soon become an “aquatic desert” and attributes the problems to recent weather conditions in the Midwest: heavy rainfall and flooding increases the levels of nutrients and pollutants in the river. All of these compounding problems will contribute to the 2013 possibly record-setting dead zone.
Scientists state that the dead zone would be less severe if a tropical storm were to enter the area, which would mix up the Gulf’s waters and facilitate oxygenation. The irony of this fact is that it leaves Louisiana residents in a less-than-ideal situation.
To read more about the causes and effects of dead zones, check out NOAA’s State of the Coast website: http://stateofthecoast.noaa.gov/hypoxia/dead_zone.html.