双氰胺和氢醌添加对堆肥温室气体排放的影响

为实现畜禽粪便堆肥过程温室气体和NH₃的同步减排，在添加一定氢醌的基础上，探究双氰胺添加比例和添加时间对堆肥温室气体和NH₃排放的影响。以猪粪和玉米秸秆为堆肥原料，设置5个堆肥处理：对照处理，添加0.03%氢醌处理，在氢醌的基础上第19 d添加0.1%的双氰胺处理、第0 d添加0.2%的双氰胺处理和第0 d与19 d各添加0.1%的双氰胺处理。在60 L的发酵罐中进行40 d的堆肥试验。结果表明：添加干质量0.1%~0.2%的双氰胺和0.03%的氢醌并未对猪粪堆肥腐熟度造成影响；氢醌作为脲酶抑制剂对堆肥NH₃和温室气体排放影响较小，在此基础上添加双氰胺可减少8.88%~12.94%的NH₃排放、6.79%~13.55%的CH₄排放和24.71%~35.83%的N₂O排放，总温室效应可降低18.61%~19.97%。考虑到经济成本和减排效果，建议在堆肥降温期添加双氰胺。

Effects of dicyandiamide and hydroquinone on greenhouse gas emissions during composting

Dicyandiamide and hydroquinone have been widely used to improve crop yield and reduce nitrogen loss in farmland. With the aim of achieving simultaneous emission reduction of greenhouse gases and ammonia during manure composting, this study explored the effects of dicyandiamide with different addition ratios and addition times on greenhouse gas and ammonia emissions based on the addition of hydroquinone during composting. In this study, pig manure and corn straw were used as compost materials, and five composting treatments were carried out for 40 days in a 60 L composting vessel. The control check continued without any additives, the HD treatment condition was supplemented with only 0.03% dry weight hydroquinone, and the other three treatments involved the addition of hydroquinone, 0.1% dicyandiamide on the 19th day, 0.2% dicyandiamide on the 0th day, and 0.1% dicyandiamide on the 0th and the 19th days. The results showed that the addition of 0.1%~0.2% dicyandiamide and 0.03% hydroquinone had no substantial adverse effects on the composting process of pig manure and corn straw. Hydroquinone, as a urease inhibitor, had little effect on ammonia and greenhouse gas emissions, but adding dicyandiamide on the basis of hydroquinone addition reduced NH₃ emissions by 8.88%~12.94%, CH₄ emissions by 6.79%~13.55%, and N₂O emissions by 24.71%~35.83%; the total greenhouse effect could be reduced by 18.61%~19.97%. Considering the economic cost and emission reduction effect, it is suggested that dicyandiamide should be added during the composting cooling period.