1a. Objectives (from AD-416):
The objectives of this cooperative research project: 1) Determine spatial distributions, concentrations and types of mineral nutrients and microbes in swine lagoon effluent as affected by environment and lagoon management. 2) Determine the influence of environmental factors and agronomic practices on the fate and transport of lagoon mineral nutrients and microbes to water, soil and plants following land application of swine lagoon effluent.
1b. Approach (from AD-416):
Work will be done on cooperator farms located in Lowndes, Chickasaw, and Clay Counties, Mississippi. ARS researchers will work with cooperator farm managers in establishment and maintenance of multi-year on farm experiments designed to identify, quantify and determine the fate and transport of nutrients and microbes and to generate data and new information to improve effluent and crop management practices. ARS researchers will work with cooperator farm managers to collect swine lagoon effluent, soil, and crop plant samples from cooperator farms. Samples will be transported to ARS Waste Management and Forage Research Unit laboratories at Mississippi State, Mississippi for nutrient and microbial analyses.
3. Progress Report:
Data from a completed study of seasonal changes in nutrients and fecal and pathogenic bacteria in lagoon effluent were analyzed and the results reported in a refereed journal article. A study of swine mortality composting using poultry litter and swine lagoon effluent as supplemental sources of nitrogen was continued. Compost samples were collected and analyzed for nutrients and bacteria. A study of swine effluent fertilization for bioenergy crop production evaluated napier grass in a center pivot irrigation spray field for tissue nutrient levels and total biomass. A study examining survival and decay rates of selected bacteria in swine lagoon effluent, poultry litter, and municipal biosolids applied to grass hay field soil was continued. Lagoon effluent was surface applied or injected and soil samples were collected and analyzed for nutrients and bacteria. Summary results were regularly reported to the cooperator.