Effect of Partially Covering Turkey Litter Surface on Ammonia Emission

Abstract

<p>Volatilization and ammonia (NH3) gas emission rate (ER) from poultry manure or litter is influenced by numerous factors including the nature and area of the emitting surface. In this study, the effect of the amount of exposed surface area of turkey litter on NH3 emission was investigated. Samples of turkey litter were obtained from stockpiled litter for a turkey growout barn. The study was conducted in four environmentally-controlled emission chambers maintained at 21±1oC and a concomitant relative humidity of 50±5%. Four different treatments were investigated where 0% (Control), 25%, 50% and 75% of the litter surface area was covered with plywood boards. The boards were periodically shifted to different positions to simulate movement of the turkeys in the barn. The NH3 concentration, litter temperature, air temperature and airflow rate through each chamber were measured continuously over a 6-d experimental period and replicated 3 times. NH3 ER was calculated from the concentration and air-flow data. The results revealed that the initial placement of the covers on the litter suppressed NH3 ERs to varying degrees. The covers served as physical barriers to NH3 emission and tended to temporarily reduce and delay of the emission but did not affect the overall total NH3 emission. Periodic shifting of the covers resulted in the escape of NH3 trapped underneath the covers resulting in similar overall NH3 ERs among the different treatments. The NH3 ER was linearly related to litter temperature, moisture content, storage time and pH and these relationships have been developed.</p>