2008 Annual Report 1a.Objectives (from AD-416) 1. Determine the effects of conservation tillage, cover crops, and composted municipal sludge on soil quality and crop yield. 2. Determine the biomass production rates of grass, wetland, and horticultural species grown as floating vegetative mats in wastewater lagoons, and the value of this material as a soil amendment following composting. 3. Determine the effect of strip versus conventional tillage systems (receiving poultry litter or inorganic fertilizers as based upon soil test results) on N cycling and C accretion rates in Coastal Plain soils. Determine NO3-N and NH4-N concentrations in shallow seasonally perched groundwater from these systems. Determine the effectiveness of grass buffers, including buffer length and grass species in assimilating nutrients in surface runoff from poultry litter applied to cotton. 4. Determine mineralization rates of poultry litter in southeastern Coastal Plain soils. 1b.Approach (from AD-416) Field and laboratory studies will be conducted to determine if the use of conservation tillage, cover crops, and composted municipal sludge will improve soil quality (moisture retention, hydraulic conductivity, bulk density and C, N, P, and K levels) and crop quality and yield on a sandy coastal plain soil. Field studies will be conducted to determine whether grasses, wetland, or horticultural species can be found that will grow on floating platforms in the high ammonium, low oxygen wastewater of anaerobic animal wastewater lagoons; whether the biomass from these species can be harvested and composted to produce a soil amendment; and whether the nutrient content of soil amendments will be superior to composted land based plants grown under conventional fertility systems. Field studies will be used to determine the effect of strip versus conventional tillage systems (with and without poultry litter) and of grass species selection and buffer length on: N cycling, C accretion rates, and nutrient assimilation from surface runoff during cotton production. Field and laboratory studies will also be conducted in collaboration with the ARS mineralization group to determine the effects of soil type, moisture, and temperature on the potential mineralization rates of poultry litter in southeastern Coastal Plain soils. 3.Progress Report Research focused on Problem Area 3: Management Tools for Indexing and Evaluating Nutrient Fate Component, of the Nutrient Management section of the National Program 206 Manure and Byproduct Utilization Action Plan and Problem Area 3, Byproducts Component, of the Byproduct Utilization Technologies section of the National Program 206 Manure and Byproduct Utilization Action Plan. A replicated study on floating vegetated mats was completed at Southern Select Farm. Five different plant species (Giant reed, St. Augustine grass, Tifton 85 bermudagrass, Common bermudagrass, and Wild Millet) were grown on floating mats. The mats were periodically harvested and the biomass weighed and plant tissue dried for analyses. Research continued on a Southeast Watershed Research Lab group project at the Gibbs Farm. Analyzing of water samples from wells, tile drains, and leaching cores. Research continued on a project determining the impact of cropping/conservation tillage systems on N cycling, soil moisture retention, and yields. Cores with resin beads were periodically installed and then removed after 3 months to measure N leaching. The first stage of a floating mat project using fisheries waste water was implemented during Fiscal Year 2008. A network of 36 tanks installed at the University of GA Fisheries unit in Tifton was used to test 12 different plant species for suitability for growth on floating mats. The species tested included St. Augustine grass, Tifton 85 bermudagrass, common bermudagrass, canna lilies, iris, wild millet, bulrush, cattail, border grass, napier grass, giant reed, and maidencane. The best performer was determined to be the iris. The worst was the wild millet, which died. Bamboo from the UGA bamboo station near Savannah was recently substituted for the wild millet. Four additional tanks were recently purchased to test two additional species. The water quality portion of the study will start in 2009. A project comparing different fertility treatments (with or without poultry litter) on Napier grass at the Ponder Farm was continued during FY 2008. Soil cores down to 1m were collected from each plot and analyzed for total carbon and nitrogen as well as microbial biomass carbon and nitrogen. Work was initiated on the Berrien Co. dryland farming project. Shallow ground water wells (9.5 ft) were installed on the borders of each research field. These will be used both to determine depth to shallow ground water and water quality as impacted by farming practices. 4.Accomplishments 1. Nitrogen mineralization from broiler litter applied to southeastern Coastal Plain soils. A field study was conducted to determine nitrogen (N) mineralization from broiler litter (BL) in two Coastal Plain soils of differing texture, sand (Tifton loamy sand) or clayey (Greenville sandy clay loam). These soils represented the broad range in surface textures commonly found in soils used for agricultural production in the southeastern Coastal Plain. Amounts of N in the soil from BL mineralization over 70 days were identical for both soils, 46.4 mg N kg-1 soil, but differences occurred in timing of the mineralization processes. In the sandy Tifton soil, depletion of ammonium and nitrification of the ammonium to nitrate occurred simultaneously. In the clayey Greenville soil, ammonium concentrations from BL mineralization increased for 21 days and then decreased until reaching background levels by 70 days. It was concluded from the study that there is a high probability that BL mineralization rates will be significantly slower on the more clayey Coastal Plain soils than on very sandy ones, and that farm managers should take these rates into consideration when planning timing and amounts of BL applications. The research addresses National Program 206 Manure and Byproduct Utilization Action Plan, Problem Area 3, Management Tools for Indexing and Evaluating Nutrient Fate Component of the Nutrient Management . 5.Significant Activities that Support Special Target Populations None. 6.Technology Transfer Review Publications Griffin, T.S., Honeycutt, C.W., Albrecht, S.L., Sistani, K.R., Torbert Iii, H.A., Wienhold, B.J., Woodbury, B.L., Hubbard, R.K., Powell, J.M. 2008. Nationally coordinated evaluation of soil nitrogen mineralization rate using a standardized aerobic incubation protocol. Communications in Soil Science and Plant Analysis. 39:257-268. Hubbard, R.K., Bosch, D.D., Marshall, L.K., Strickland, T.C., Rowland, D., Griffin, T.S., Honeycutt, C.W., Albrecht, S.L., Sistani, K.R., Torbert Iii, H.A., Woodbury, B.L., Powell, J.M., Wienhold, B.J. 2008. Nitrogen Mineralization of Broiler Litter Applied to Southeastern Coastal Plain Soils. Journal of Soil and Water Conservation. 63(4):182-192.