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
Levels of fecal and pathogenic bacteria were compared in aerosols, soil, and forage plant samples during and after application of swine manure lagoon effluent. A study of temporal changes in nutrients and fecal and pathogenic bacteria in lagoon effluent was continued and the final samples collected in 2011. Compost samples from a swine mortality composting facility were collected and analyzed for selected nutrients and bacteria. Composting protocols on the farm were modified to include poultry litter as a nitrogen source. A new study to examine the use of swine lagoon effluent as fertilizer for biomass energy crop production of Napier grass was begun with the establishment of replicated grass plots in a center pivot irrigation spray field. A new study examining survival and decay rates of selected bacteria in swine lagoon effluent and municipal biosolids applied to grass hay field soil was initiated with the establishment of replicated plots in a field that had never been fertilized with swine lagoon effluent. Summary results were regularly reported to the cooperator. The ADODR monitored this project by frequent discussions and other contact with the principal scientist involved in this research.