What lies ahead for the
DEAD ZONE?
When production increases in an ecosystem, organic matter, such as algal cells and fecal pellets, increases. This situation can lead to hypoxia when decaying bottom organic matter depletes oxygen and water stratification blocks oxygen replenishment. Upwelling oxygen-rich water or destruction of the stratification can alleviate this problem. Courtesy of the U.S. Environmental Protection Agency.
It is clear that, unless the nutrient load entering the northern Gulf is reduced, destructive hypoxia will appear each summer. However, three fundamental issues remain for scientists and regional stakeholders to address:
- What are the best ways to improve the Mississippi’s water quality and reduce the river’s nutrient load?
- What future effect will the Dead Zone have on Gulf fisheries?
- Can all partners in the watershed cooperate to improve the quality of the water in the Mississippi?
Reducing the Nutrient Load
A national task force, the Mississippi River—Gulf of Mexico Watershed Nutrient Task Force (the Hypoxia Task Force), has devised an action plan (www.epa.gov/msbasin, click on Challenges) to mitigate hypoxia in the northern Gulf of Mexico. Its goals include:
- develop a budget proposal
- establish subbasin committees
- determine research and nutrient reduction strategies
- expand monitoring programs in the basin and the Gulf
- complete a reconnaissance study
- identify nutrient point sources
- begin wetland/buffer restoration projects
- implement best management practices
Among subsequent initiatives launched by universities and basin stakeholders,William Mitsch of Ohio State University and John Day of Louisiana State University have developed a watershed-wide plan to improve the water quality of the Mississippi, reduce its nutrient load and diminish the effects of hypoxia.
The recently completed $150,000 study, funded by the state of Louisiana and the U.S. Army Corps of Engineers, complements the goals of the Task Force action plan. It documents the loss of extensive water-filtering buffer zones along the Mississippi and its tributaries and recommends an ambitious plan to restore tens of millions of riverside wetland and forest acres at a cost of tens of billions of dollars.
Despite the enormity of this cost, when compared to the $8 billion needed to restore 1.4 million acres in the Florida Everglades, this restoration plan actually costs substantially less per acre. Besides restoring buffer zones, the plan also advocates establishing a nitrogen-credit system with incentives for the agricultural industry to reduce its application of nitrogen-based fertilizers.
Under the current Farm Bill, the Farm Security and Rural Investment Act of 2002, two important Department of Agriculture conservation strategies are already being implemented. Marginal wet croplands are being taken out of production and converted to wetlands by the Natural Resources Conservation Program, and the Farm Service Agency has worked to cover thousands of acres of easily eroded land with grass or trees, producing riverside buffer zones.
Future Fisheries
Better research is essential to predicting the long-reaching effects hypoxia may have on Gulf ecosystems and Louisiana fisheries. Revised research strategies are now exploring the consequences of the Dead Zone by gathering fisheries data in new ways. Instead of relating catch data to the port where the catch arrives, some fishing vessels have been equipped with global-positioning transponders that record the exact location where the catch is actually made. These “trip-ticket” data should prove invaluable in determining the health and forecasting the future of the Gulf fisheries.
Watershed Cooperation
The national Hypoxia Task Force supports establishing subbasin committees to coordinate research and actions to reduce nutrients. For example, Louisiana has joined Arkansas, Mississippi, Missouri and Tennessee in the Lower Mississippi Subbasin Committee. This group is identifying demonstration watersheds where the best management practices for nutrient reduction can be developed and showcased.
Avoiding new hierarchies, both the national and subbasin committees are utilizing existing organizations, programs and activities to further the goals of the action plan. Within Louisiana, the State Hypoxia Working Group has participants from organizations involved in Breaux Act coastal restoration, along with the Louisiana departments of Environmental Quality and Agriculture and Forestry, the Governor’s Office of Coastal Activities and the Mississippi River Basin Alliance.
“We have a unique situation where all of these agencies are working together toward a common goal,” said Dugan Sabins of the state committee.
Given the complexity of the hypoxia problem, the vast extent of the watershed involved and the severity of the potential consequences, scientists hope that funding for research and resolution is provided before full recovery is impossible.