Hyperthermophilic pretreatment composting can reduce ammonia emissions by controlling proteolytic bacterial community and the physicochemical properties

Proteolysis is the rate-limiting step in the mineralization of organic nitrogen into ammonium (NH4+) and thereby the ammonia (NH3) released during the composting. However, the dynamics of bacterial proteolytic communities related to NH3 emissions during the composting systems are mostly unknown. This study aimed to examine and compare the effects of hyperthermophilic pretreatment composting (HPC) and traditional composting (TC) methods on (i) the difference of NH3 loss and nitrogenous compounds; (ii) the dynamics of the proteolytic bacterial community involved in the proteolysis and (iii) the correlation between the proteolytic bacterial community, biophysiochemical characteristics and NH3 loss. Results revealed that the HPC decreased NH3 loss by 42