Effect of turning and covering on greenhouse gas and ammonia emissions during the winter composting

The effect of turning and covering on greenhouse gas and NH3 emissions during the composting of pig faeces was evaluated in this paper. Chopped cornstalk was used as bulking agent and carbon source. Results showed that the heat created by the degradation would maintain the compost piles at thermophilic phases more than 3 weeks to ensure the sanitation effect. But the cold weather would freeze the pile when the degradable carbon was exhaust, then caused the maturation cease. About 0.14%-0.76% of initial carbon was lost as CH4, and the NH3 and N2O emissions accounted the initial nitrogen 10.3%-29.5% and 0.81%-3.93% respectively. Statistic analysis showed that the turning could decrease the N2O and CH4 emission, but increase the NH3 losses significantly. Covering could increase the CH4 production, decreased the NH3 losses, but could not affect the N2O emission significantly.