Initial Ammonia and Nitrous Oxide Emission From Land Application of Different Livestock Wastes and Nitrogen-Base Fertilizers.

In the era of sustainability, utilization of livestock wastes as soil amendment to provide micronutrients for crops is very economical and sustainable.  It is well understood that livestock wastes are comparable, if not better, nutrient sources for crops as chemical fertilizers. However, the utilization of these livestock wastes in crop production may have unwanted side effects to the environment.  For instance, land application of these livestock wastes may produce unwanted emission of anthropogenic air pollutants, greenhouse gases, and other precursors to particulate matters that may affect air quality at local and regional levels.  In this study, we examined the emission of ammonia and nitrous oxide (a potent greenhouse gas) from soil amended with swine manure, poultry litter, urea, and ammonium nitrate. The experimental objective was to compare the initial emission of ammonia and nitrous oxide from land application of these animal wastes and nitrogen-base fertilizers.  Static flux chambers along with photoacoustic gas analyzer were used to monitor ammonia and nitrous oxide concentrations.  The results show that swine amended plot has the highest ammonia flux (5.793 ± 1.200 mg per m² per hr), a four folds higher than both nitrogen-base fertilizer plots.  However, the poultry litter amended plot has the highest initial nitrous oxide flux (1.649 ± 0.481 mg per m² per hr). Both nitrogen-base fertilizer plots have the smallest initial ammonia and nitrous oxide fluxes. Even though animal wastes may be a good alternative nutritional sources for crop production over chemical fertilizers, surface application of these livestock wastes may not be appropriate due to potential air pollution, especially in reducing greenhouse gas emission.