Location: Dale Bumpers Small Farms Research CenterTitle: Effects of poultry litter injection on ammonia volatilization, nitrogen availability, and nutrient losses in runoff
|KULESZA, STEPHANIE - VIRGINIA POLYTECHNIC INSTITUTION & STATE UNIVERSITY|
|MAGUIRE, RORY - VIRGINIA POLYTECHNIC INSTITUTION & STATE UNIVERSITY|
|THOMASON, WADE - VIRGINIA POLYTECHNIC INSTITUTION & STATE UNIVERSITY|
|HODGES, STEVEN - VIRGINIA POLYTECHNIC INSTITUTION & STATE UNIVERSITY|
Submitted to: Soil Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/14/2014
Publication Date: 9/9/2014
Citation: Kulesza, S.B., Maguire, R.O., Thomason, W.E., Hodges, S.C., Pote, D.H. 2014. Effects of poultry litter injection on ammonia volatilization, nitrogen availability, and nutrient losses in runoff. Soil Science. 179(4):190-196.
Interpretive Summary: Poultry litter is often used as organic fertilizer in farming systems, but the common practice of spreading litter on the surface of fields can result in substantial nutrient losses. Researchers injected poultry litter beneath the soil surface to determine whether this application method could help prevent nutrient losses and make the litter nitrogen more available to crops. They found that litter injection increased available nitrogen in the soil by 52-99% and decreased nutrient losses by 53-99%, when compared to surface-applied litter. This study is of interest to agricultural producers, extension personnel, scientists, and the general public because poultry litter injection can provide an effective management option to help farmers reduce nitrogen losses in conservation tillage systems, increase nitrogen recovery in the following crop, and reduce nutrient losses in runoff.
Technical Abstract: Poultry litter is a common organic amendment in agricultural production systems, but nutrient losses can reduce the effectiveness as a fertilizer. Three studies were conducted to determine differences in nutrient availability and loss when comparing injection and surface application. These investigated nitrogen (N) mineralization, ammonia-N (NH3-N) volatilization, and runoff losses of nutrients by conducting a soil incubation, closed chamber volatilization study, and rainfall simulation. In all studies, poultry litter was applied at a rate of 6.7 Mg/ha either on the surface or injected and compared to an unamended control. In the N mineralization and volatilization studies, two soil types were compared: Shottower loam and Bojac sandy loam. After a 40 day N mineralization study, injection increased total inorganic N by 52% and 99% for the Loam and Sandy loam soils, respectively, when compared to surface application. Cumulative losses of NH3-N from injected and surface applied poultry litter after a 7 day volatilization study were 3% and 121%, respectively, of the ammonium-N (NH4 +-N) added to the Shottower loam. In the Bojac sandy loam, cumulative losses of NH3-N were 9% for injected and 153% for surface applied after 7 days. Injection reduced Total Kjeldahl N (TKN), Total Kjeldahl P (TKP), dissolved reactive P (DRP), dissolved NO3-N, and dissolved NH3-N by 59, 53, 96, 73, and 99%, respectively, when compared to surface application. Injection reduced NH3-N volatilization and nutrients in runoff to levels of the control. These studies show that injection increases plant available N while decreasing losses through volatilization and runoff.