黄土及其他添加物对猪粪贮存过程氨气和温室气体排放的影响

畜禽粪肥在贮存阶段养分损失严重,是CO_2、CH_4、NH_3和N_2O等大气污染物的重要排放来源.本文采用室内培养方法,研究了添加黄土、秸秆、生物炭和膨润土对猪粪贮存过程中氨气及温室气体排放的影响.结果表明,添加10%用量的生物炭和膨润土处理的CO_2累积排放量与不添加任何添加物的猪粪对照相比分别降低了15.4%和20.9%,N_2O累积排放量分别降低了19.8%和37.6%.添加膨润土处理的NH_3损失量显著增加,但添加生物炭和膨润土处理的综合温室效应与猪粪对照相比均显著降低.添加10%秸秆处理的CH_4和NH_3累积排放量分别较猪粪对照降低了56.8%和95.8%,但其综合温室效应与对照相比差异不显著.模拟黄土垫圈过程添加黄土处理的氨气及温室气体累积排放量均显著降低,综合温室效应显著低于其他处理(p0.05).可见,黄土垫圈是保蓄粪肥碳、氮养分的有效措施,猪粪贮存阶段添加少量生物炭、膨润土对于减少粪肥综合温室效应具有积极作用.

Effects of mixing loess and other additives with pig manure on ammonia and greenhouse gas emissions during storage

Significant amount of gaseous pollutants like CO₂, CH₄, NH₃ and N₂O are released during manure management such as its storage and transportation. An incubation experiment was carried out to investigate the influence of addition of loess, straw, biochar and bentonite on ammonia and greenhouse gas emissions during pig manure storage. The results showed that the cumulative CO₂ emissions of biochar and bentonite treatments decreased by 15.4 and 20.9% compared to the control (pig manure without additives), and the cumulative N₂O emissions by 19.8%and 37.6%, respectively. Although NH₃ volatilization in bentonite treatment was significantly increased, the global warming potential of biochar and bentonite treatments were both lower than pig manure. Compared with control, the cumulative emissions of CH₄ and NH₃ from straw treatment were decreased by 56.8% and 95.8%, respectively. While there was no significant difference in greenhouse gas emissions between the two treatments. Compared with biochar and bentonite treatments, adding loess treatment significant reduced ammonia volatilization and global warming potential. It is concluded that adding loess to livestock housing is an effective method to conserve nutrients and reduce global warming potential from manure; and adding low rates of biochar or bentonite also has positive effects to reduce emissions of greenhouse gases during manure storage.