Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/1994
Publication Date: N/A
Interpretive Summary: With the current system used for poultry production, a bedding material such as wheat straw, rice hulls or wood shavings is added to the floor of poultry houses and five or six flocks of broilers are grown on it over a one year cycle. After that time, the litter is removed and is normally land applied as fertilizer. This re-use of litter for several flocks results in the production of ammonia gas (NH3), which can be produced in high quantities in poultry houses. High levels of ammonia adversely affect chickens and farm laborers. Results from this study indicate that alum (aluminum sulfate) greatly reduces ammonia volatilization from poultry litter. This compound was also shown to immobilize phosphorus in litter, which should reduce water pollution. Since high ammonia levels in poultry houses cause major economic losses to producers, the use of alum as a litter amendment should result in increased profitability to producers, while decreasing the negative environmental impact caused by phosphorus runoff from land application of poultry litter.
Technical Abstract: Ammonia (NH3) volatilization from poultry litter results in a buildup of atmospheric NH3 in chicken houses, which is detrimental to both farm laborers and birds. Ammonia loss from litter is detrimental to the external environment because it results in acid rain, as well as low N/P ratios in litter, which increase the likelihood of excessive P runoff into adjacent water bodies. The objectives of this study were to (1) determine the effect of various chemical amendments on NH3 volatilization from litter, and (2) determine the effect of these amendments on N and P transformations in litter. A laboratory study was conducted using the following amendments: Ca(OH)2, alum, alum + CaCO3, ferrous sulfate, and MLT (a commercial product). Ammonia-free air was continuously passed through air-tight chambers containing amended litter and any NH3 volatilized from the litter was trapped in boric acid solutions. At this time, the litter was analyzed for pH, EC, soluble organic C (SOC), metals, soluble and total forms of N and P. The results of this study indicated that the addition of alum to poultry litter dramatically reduces NH3 volatilization (up to 99% less volatilization than controls). Decreases in volatilization resulted in higher total N. Alum was also very effective in decreasing water soluble P levels in litter. Therefore, we are proposing the use of alum as a litter amendment in poultry houses. Alum treatment of poultry litter should decrease atmospheric NH3 loading, as well as decrease P runoff from fields fertilized with litter, which would decrease the threat of eutrophication of waters in poultry producing areas. Reducing NH3 levels in poultry houses should also have a positive effect on the health of farm laborers and poultry.