Water Quality Benefits
Reduction of Hypoxia
Hypoxia in the Gulf of Mexico has received national attention because of its potential to cause large-scale ecological and economic impacts. Hypoxia is an area of depleted oxygen (<2 parts per million) that forms in the Gulf of Mexico each summer as a result of excess nutrients (primarily nitrogen and phosphorus) carried by the Mississippi River and seasonal stratification (layering) of Gulf waters. The size of the Gulf hypoxic zone off the Louisiana and Texas coasts average more than 5,000 square miles each year, or about the size of Connecticut. Action plans for mitigating Gulf hypoxia call for states, tribes and federal agencies within the Mississippi River basin to develop viable strategies for nutrient reduction, including identifying opportunities to restore floodplain wetlands.
Removal of Sediments
Additional reforestation in the project area will help facilitate the role of the nation’s largest bottomland forest floodplain ecosystem as the “final filter” of the 1.25-million-square-mile Mississippi River watershed. According to the NRCS (August 2013), each acre of Lower Mississippi River region’s cropland converted to forest, on average, reduces the annual loss of 84 pounds of nitrogen and phosphorus. Land put in long-term conserving cover (e.g. forest) nearly eliminates soil erosion and sediment loss. Sediment loads delivered to rivers and streams in the Lower Mississippi River Valley average 1.15 tons per acre per year. The input of agricultural pesticides will be eliminated on reforested land.
A 2013 modeling study by scientists at U.S. Forest Service’s Center for Bottomland Hardwoods Research concluded that “converting agricultural lands close to streams into forests would greatly lessen water outflow and reduce the effects of sediment load as far as the Gulf of Mexico.”
Improved Habitat for Migrant Waterfowl
Annual and long-term fluctuations in flooding have created a complex of forested wetland types that provide habitat for eight high-priority species of migratory and resident waterfowl: hooded merganser, Canada goose, gadwall, northern pintail, green- winged teal, ring-necked duck, mallard and wood duck. Reforestation of agricultural lands in the project area will improve habitat for migrant waterfowl by providing additional feeding opportunities in a variety of forested habitat types. Submerged and floating plants interspersed with scrub/shrub wetlands and different forest associations (bald cypress/water tupelo, overcup oak/red maple, pin oak/Nuttall oak and willow oak/cherrybark/oak) provide waterfowl an abundance of food, including seeds, insects, snails, spiders, crayfish and other foods.
During winter months shrub/scrub and forested wetlands provide roost habitat that help waterfowl conserve body heat and avoid disturbances from natural predators. These forested wetlands are also used as pair bonding sites by many species during spring migration and provide critical brood habitat for resident wood ducks and hooded mergansers. Reforestation of agricultural land in the batture is both economically and ecologically effective because most of the land has not been leveled, which ensures a more diverse array of forested wetland habitat types will be available to wildlife.
More Habitat for Forest-dwelling Songbirds, Raptors, and Others
The loss and fragmentation of forest habitat in the region, along with the loss of complex forest structure, has contributed to declining population trends for many forest-dwelling songbirds, certain raptors and a forest-dwelling shorebird, the American woodcock. Specific nesting habitat requirements vary among species, but many forest-interior songbirds share broad requirements for complex vertical and horizontal forest structure for nesting and foraging.
Two songbirds of high conservation concern, Swainson’s warbler and cerulean warbler, are among the species that depend on larger, more complex forested blocks that can be provided through restoration and management. Other songbird species of concern, including prothonotary warbler, Kentucky warbler and Acadian flycatcher, also will benefit from forest restoration.
One forest-dwelling raptor species of high conservation concern, the swallow-tailed kite, has been nearly extirpated from all but the southern portions of the project area. Experts believe it may re-populate the Lower Mississippi River region as larger forest blocks are restored. The first nesting attempts in nearly a century were recorded in Arkansas in recent years.
The project area forms part of one of the continent’s major migratory routes, the Mississippi Flyway. Some 60 percent of the bird species found in North America use Lower Mississippi River habitats during their life cycles. Dozens of forest-dwelling species traverse the region to and from northern nesting grounds and wintering areas in the tropics. Some, such as the rusty blackbird, nest in the boreal forests of Canada but depend heavily on Lower Mississippi River forests for wintering. The population of rusty blackbirds has declined more than 90 percent in the last 40 years, as both its nesting and wintering habitats have diminished.
Reforestation in the Lower Mississippi River batture makes economic sense. It will:
- Reduce financial demand for disaster assistance and crop insurance on lands with repeated losses from flooding.
- Help protect federal navigation and flood-control infrastructure (levees) from erosion and catastrophic failure during floods.
- Help diversify local and regional economies by providing highly valued hunting and other outdoor recreational activities. The region includes 18 of the 50 poorest counties in the nation.
Reforestation in the batture is also cost-effective. Land values are relatively low, and most of the land has not been leveled, which ensures that a diverse array of forested wetland habitat types will be available to wildlife.