Abstract
Composting is a sustainable alternative for the management of manure. In this study, the effects of bioaugmentation on cattle manure composting was investigated. In this study, two windrow piles were placed at 1.7 m in height, 2.1 m in bottom width, 0.6 m in top width, and 54 m in length. Microbial inoculum was added to pile 1, whereas the second pile was used as the control. After 17 days, the C:N ratio was reduced from 25.6 to 13.6 and the total nitrogen was increased from 1.89% to 3.36% in pile 1. The dominant bacteria identified in the compost samples belonged to the genera Clostridium, Bacillus, and Flavobacterium. Quantitative polymerase chain reaction indicated that the most commonly known pathogenic bacteria, Escherichia coli, Shigella, and Salmonella, were not detected in the finished material, indicating that the pathogenic microorganisms were inactivated by the composting process. Agronomic testing for cured compost indicated a C:N ratio of less than 15 and NH4+-N:NO3--N ratio of less than 1. The whole process of windrow composting resulted in net greenhouse gas (GHG) emissions of 157.94 tCO(2)-e and a global warming factor (GWF) of 1.04 tCO(2)-e.t(-1) manure composted. This study showed that although bioaugmentation is a feasible treatment method for manure, GHG emissions need to be monitored.