ABSTRACT

Layer manure (LM) and spent mushroom substrate (SMS) are two kinds of nitrogen (N) rich solid wastes generate in the poultry breeding and agriculture production. Composting is an effective way to recycle the LM and SMS. However, a large amount of N in the LM and SMS was lost via volatilisation during composting, with negative environmental and economic consequences. This study investigated the effect of incorporating biochar at the ratio of 5%, 10%, and 15% (w/w) during co-composting of LM and SMS on ammonia (NH₃) and nitrogen oxide (N₂O) volatilisation and N retention. After the 35-day composting, the results showed that the pile temperature and seed germination index in biochar treatments were significantly improved in comparison with control treatment. The nitrogen in all treatments was lost in the form of N₂O (0.05∼0.1%) and NH₃ (13.1∼20.2%). Likewise, the total nitrogen loss was 28.9%, 20.3%, and 24.9%, respectively, of which N₂O-N accounts for 0.05∼0.10%. Compared with control treatment, the total amount of NH₃ volatilisation in biochar treatments of 5%BC, 10%BC and 15%BC was decreased by 21.2%, 33.1%, and 26.1%, respectively. The total amount of N₂O emission was decreased by 39.0%, 13.2%, and 1.6%, respectively. Adding 10% and 15% biochar can significantly reduce NH₃ volatilisation while adding 5% biochar treatment didn't significantly reduce NH₃ emissions but showed the best performance in reducing N₂O emission. The addition of 10% biochar in co-composting of LM and SMS is the recommended dosage that exhibited the best performance in improving composting quality and reducing nitrogen loss.

摘要

蛋鸡粪肥（LM）和废蘑菇基质（SMS）是家禽养殖和农业生产中产生的两种富含氮（N）的固体废物。堆肥是回收LM和SMS的有效方法。然而，LM 和 SMS 中的大量 N 在堆肥过程中通过挥发损失，对环境和经济造成负面影响。本研究调查了在 LM 和 SMS 共堆肥过程中以 5%、10% 和 15% ( w/w ) 的比例掺入生物炭对氨 (NH ₃ ) 和氮氧化物 (N _{2 ) 的影响}O) 挥发和 N 保留。结果表明，堆肥35天后，生物炭处理的堆温和种子发芽指数较对照处理有显着提高。所有处理中的氮均以N ₂ O（0.05～0.1%）和NH ₃（13.1～20.2%）的形式损失。同样，总氮损失分别为28.9%、20.3%和24.9%，其中N ₂ O-N占0.05～0.10%。与对照处理相比，5%BC、10%BC和15%BC的生物炭处理NH ₃挥发总量分别降低了21.2%、33.1%和26.1%。_{N 2}的总量O 排放量分别减少了 39.0%、13.2% 和 1.6%。添加10%和15%的生物质炭可以显着降低NH ₃的挥发，而添加5%的生物质炭处理并没有显着降低NH _{3排放，但在降低N 2} O排放方面表现出最佳效果。LM和SMS共堆肥中添加10%生物炭是提高堆肥质量和减少氮损失的最佳推荐用量。