Broiler house ammonia emission monitoring: Spatio-temporal dynamics

Ammonia emission from animal feeding operations has drawn great attention due to its environmental issues and negative health effects on animals and human. In the first part of this study, flux chamber method and whole-house monitoring method were used to estimate the ammonia flux rate from litter floor of a mechanically ventilated commercial broiler house in northwest Arkansas, during two winter flocks and one summer flock. A closed flux chamber system was utilized in this study to estimate the ammonia volatilization rate from litter floor. Large spatial and temporal variations of ammonia flux rates were obtained in the house. Litter samples were taken on each test day for litter moisture determination for all three flocks. Surface litter temperature was measured on flux test day for the summer flock. Whole-house ammonia emission rate was estimated by measuring whole-house ammonia concentration, fan capacity and fan operation status. A linear relationship was captured between the ammonia flux rates estimated by flux chamber method and whole-house monitoring method for the two winter flocks. The second part of this study investigated vertical stratification of ammonia concentration in the broiler house. In general, the ammonia concentration decreased as the air exchange rate increased. And the ammonia concentration decreased vertically while increasing the distance away from the litter floor. Moreover, the vertical stratification of ammonia concentration was reduced as the air exchange rate increased in the house.