Effects of biochar and wood vinegar co-application on composting ammonia and nitrous oxide losses and fertility.

Composting faces challenges with nitrogen (N) losses through ammonia (NH) and nitrous oxide (NO) emissions. In this study, wood vinegar (WV) and biochar (BC) were applied individually or combined into wheat straw and chicken manure composting. Results showed that BC and WV reduced NH volatilizations by 22-23 % individually, but their combined application achieved a 59 % reduction. However, this combination increased NO emissions by 174 %. The BC + WV treatment improved compost quality, evidenced by increased total N content by 22 % and enhanced the biological index, promoting additional dissolved organic matter production. Overall, BC and WV applications improved compost quality, reduced gaseous N losses, and supported the re-utilization of agricultural residues. The combined use of BC and WV significantly enhances compost quality and reduces NH emissions, offering a promising solution for sustainable agricultural residue management.