• Develop alternative and innovative farming systems for improved water quality and ecology in the Mississippi Delta;
• Increase the knowledge to design and evaluate economical environmentally-sound best management practices (BMP's) as components of farming systems;
• Assess the effects of these agricultural activities on surface- and shallow ground-water quality; and
• Increase awareness and promote adoption by farmers and landowners of alternative farming systems to reduce adverse agricultural effects on water resources and ecological processes.

The project design involves a hierarchy of BMP's in three research watersheds located in west-central Mississippi (fig. 1). Thighman Lake watershed in Sunflower County serves as a control without BMP's. Beasley Lake watershed in Sunflower County receives nominal BMP treatment, and Deep Hollow Lake watershed in Leflore County has an intense BMP effort. The watersheds are "closed systems" with drainage into oxbow lakes. These oxbow lakes are remnants of meandering flood plain rivers which have been cut off from their respective main river channels.

The project design also allows for acquisition of information about the ability of riparian zones in the Delta to assimilate and transform agrichemicals. Success of the project wi11 be demonstrated by reduced sediment and agrichemicals transport in runoff, improved water quality and ecology, sustained high crop yields, and enhanced, sustainable fisheries in adjacent waterbodies.

The premise of the project is that economically feasible BMP's will be effective in reducing the suspended sediments and agrichemicals that leave the watersheds and enter the oxbow lakes, resulting in improvements in lake water quality and ecology such as increased light penetration and primary productivity. After implementation of BMP's, all lakes will be renovated by using rotenone and restocking with largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrocliirus). Enhanced primary production in the treatment lacks is expected to support sustainable sports fisheries.

Lake water-quality evaluations include measurements of dissolved oxygen: pH; temperature: specific conductance; suspended, dissolved, and total solids: Secchi visibility; nutrients; and chlorophyll. Lake water and bottom sediments will be analyzed for selected pesticides and trace elements and bioassayed for toxicity.

Macroinvertebrate communities, important food web components, will he characterized and quantified. This information, coupled with fisheries data (growth rates, condition factors, length-frequency distributions, and other stock-assessment measures) will be used to assess the ecological health to the oxbow lacks.

Surface-runoff and shallow ground-water samples will be collected and analyzed for sediments, nutrients, and pesticides in critical flow areas in the watersheds so that contaminant reduction by each BMP or combination of BMP's can be determined.

• Determining the role of soil cracks (very pronounced in many Delta soils) in agrichemical transport.
• Determining pesticide residues for selected indicator aquatic and terrestrial organisms in the lake ecosystems.
• Determining the effects of BMP's on the spatial variability of watershed soil properties as related to herbicide sorption and dissipation.
• Evaluating innovative weed-control technology (weed sensors).
• Evaluating ARS-developed water-quality models for their applicability to the Mississippi Delta.
• Using precision weather forecasting for timing agrichemical applications.
• Assessing socioeconomic factors related to farmer acceptance and adoption of alternative farming practices.
• Developing new immunoassays for cotton pesticides.

• no-till cotton and soybeans with winter cover crop;
• hooded pesticide sprayers and weed sensor technology;
• slotted board risers;
• slotted pipes;
• grass filter strips; and
• riparian zones.

  Watershed area: 400 acres
  Lakesize: 20acres
  Primary crops: Cotton and soybeans
  
  *Deep Hollow is a Mississippi Soil and Water Conservation Commission water-quality Model Farm Project.

• slotted boardrisers;
• slotted pipes;
• grass filter strips and
• riparian zones.

  Watershed area: 1,000 acres
  Lake size: 40 acres
  Primary crop: Cotton
  

Thighman Lake (Sunflower County)
Farming system to include no BMP's initially (control).

Watershed area: 1,900 acres
Lake size: 20 acres
Primary crops: Cotton, soybeans, rice, catfish

Participating Agencies:

Partners/Cooperators/Supporters

Mississippi State University, Mississippi Department of Environmental Quality
USDA-Natural Resources Conservation Service
Mississippi Soil and Water Conservation Commission
USDA-Farm Services Agency
Yazoo Mississippi Delta Joint Water Management District
Delta Council
Mississippi Farm Bureau Federation
U.S. Fish and Wildlife Service
Delta Wildlife Foundation
VSDA-Animal Damage Control
University of Mississippi

For further information contact: