Very low N2O emissions were observed in the B þ L amended treatment, which might be due to the rapid mineralization of organic matter, low nitrate concentration during the bioactive phase (data not shown) or dominant NH4þ-N concentration (Fig. 1e). During the thermophilic phase of composting, N2O emissions seemed to be respon sible for a relevant fraction of TKN losses in the control and lime amended treatments, as shown in Fig. 1f. Similar findings were also obtained in previous studies