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United States Department of Agriculture

Agricultural Research Service

2008 Annual Report

1a.Objectives (from AD-416)
1) Determine the factors that affect P chemistry and transport in soil, water and manure..
2)Determine the long-term impacts of manure management strategies at animal production operations, manure storage areas and pasture application sites on soil, water and air resources..
3)Develop and evaluate management practices and decision tools to limit nutrient (N and P), pathogen and pharmaceutically active compound pollution of surface waters. 3a) Determine the factors that influence surface runoff within watersheds..
4)Determine ammonia emission rates from manure at animal production operations, manure storage areas and pasture application sites; develop management practices and control technologies to reduce ammonia losses..
5)Determine the sources and occurrence of nutrients, organic wastewater compounds, pathogens and antibiotic residuals at the watershed scale.

1b.Approach (from AD-416)
Both long-term and short-term studies will be conducted. A long-term study (13 years) will be conducted on the impacts of various pasture management strategies (over grazing, rotational grazing, haying, etc.) on pasture hydrology, nutrient runoff, soil erosion and forage production. The results of this study will be utilized to revise the Arkansas Phosphorus (P) Index. Another long-term study (7 years) will be conducted to determine the effects of pasture renovation and litter incorporation on P runoff, ammonia emissions and forage yields. Ammonia emissions will also be measured from commercial broiler houses and on land following manure application. The ultimate goal of this research is to develop cost-effective best management practices (BMPs) for poultry manure management which improve air and water quality.

3.Progress Report
Most of our effort this year has been spent on revising the Arkansas Phosphorus Index, a project funded by Arkansas Natural Resources. Several hundred rainfall simulations were conducted to evaluate the effects of soil test phosphorus and various other phosphorus sources (biosolids, dairy manure, poultry manure, swine manure, and triple superphosphate) on phosphorus concentrations and loads in runoff. It was decided that while there was sufficient data to develop an index for poultry manure, more data was needed for the biosolids, dairy and swine manure. Extensive statistical analyses of the poultry manure runoff data were conducted by both ARS and University of Arkansas statisticians to determine weighting factors for the phosphorus source coefficients in the index. After an agreement was reached on the appropriate weighting factors, a study was initiated to compare this new index for poultry manure to the current index (this study is currently underway). More rainfall studies are currently underway evaluating the effects of the other phosphorus sources.

Edge of field P runoff is also being measured from 25 fields fertilized with poultry or swine manure. Each one of these fields has berms around it and is equipped with flumes and automatic samplers. The data from this study, which has been funded by an EPA 319 grant, will be used to validate the Arkansas P index.

Another EPA 319 grant is funding research being conducted at this location on P runoff from biosolids (sewage sludge). Scientists at this location discovered that P runoff could be reduced from biosolids by adding water treatment residuals (WTRs), such as alum sludge to the biosolids prior to application. Rainfall simulations are being conducted on small plots to determine the efficacy of this best management practice. Likewise, P runoff from three small watersheds fertilized with either biosolids, biosolids treated with WTRs or commercial nitrogen fertilizer is being evaluated.

The greatest accomplishment made by this CRIS over the past year was completing a study on ammonia emissions from commercial poultry houses. Ammonia emissions and fluxes were measured from four commercial broiler houses for two years. A nitrogen mass balance study was also performed. The effects of best management practices, such as treating litter with alum, incorporating litter into pastures, and using an ammonia scrubber to capture ammonia leaving poultry houses, were evaluated. (NP206; Nutrient component areas 1-4 and Atmospheric Emissions components 2, 3 and 4)

1. Quantification of ammonia emissions from poultry houses: Ammonia emissions from poultry litter result in poor poultry performance, health risks to workers, and atmospheric pollution. This is the first study conducted in the U.S. that measured ammonia losses from poultry litter in rearing facilities, during storage and following land application. Likewise, it is the first report of ammonia emissions made while conducting a mass balance for N. The total ammonia emission factor for broilers measured in this study, which includes losses in-house, during storage, and following land application was 45.5 g NH3/bird marketed. This value is less than half of the value currently used by the EPA (100 g NH3/bird). Treating litter with alum and incorporating litter into pastures were both shown to significantly reduce ammonia losses. These results will provide the poultry industry with cost-effective technologies to lower ammonia emissions and provide action agencies with better estimates of atmospheric N contamination associated with poultry production. (NP206; Atmospheric emissions component, problem area 2 – Emission factors from livestock facilities).

6.Technology Transfer

Number of the New MTAs (providing only)1
Number of Non-Peer Reviewed Presentations and Proceedings4
Number of Newspaper Articles and Other Presentations for Non-Science Audiences1

Review Publications
Tomlinson, P.J., Savin, M.C., Moore Jr, P.A. 2007. Phosphatase activities in soil after repeated untreated and alum-treated poultry litter applications. Biology and Fertility of Soils. 44:613-622.

Last Modified: 2/28/2015
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