【摘要】 【目的】研究氨氮质量浓度对鸡粪和玉米秸秆混合厌氧发酵产甲烷特性及产甲烷菌群落的影响。【方法】以鸡粪和玉米秸秆的混合物作为发酵原料，以不添加氮源的处理为对照，通过添加外源氮源设置不同氨氮质量浓度1 500、3 000、4 500、6 000 mg/L中温厌氧发酵试验，测定分析不同处理的产甲烷特性和产甲烷菌群落变化规律。【结果】氨氮质量浓度<3 000 mg/L时，对发酵系统无明显抑制作用；氨氮质量浓度≥3 000 mg/L时，厌氧消化系统受到明显的抑制，表现为产甲烷高峰期滞后、原料累积产甲烷量下降、游离氨（FAN）含量增加、挥发性脂肪酸（VFAs）积累。氨氮质量浓度为3 000、4 500、6 000 mg/L时，其原料累积产甲烷量分别为119.50、96.60、64.52 m L/gVS，较对照分别降低16.66%、32.67%、55.03%，其中，6 000 mg/L的氨氮质量浓度已超过了IC50（半抑制浓度）。当氨氮质量浓度<3 000 mg/L时，嗜乙酸型产甲烷菌属甲烷鬃菌属（Methanosaeta）为优势产甲烷菌属；当氨氮质量浓度继续提升至3 000 mg/L及以上时，产甲烷菌群发生改变，甲烷鬃菌属的相对丰度逐渐降低，而氨氮耐性较高的氢营养型产甲烷菌属甲烷八叠球菌属（Methanosarcina）和甲烷囊菌属（Methaanoculleus）的相对丰度逐渐升高。【结论】鸡粪和玉米秸秆混合发酵系统内的氨氮质量浓度高于1 500 mg/L时，对嗜乙酸型产甲烷菌产生了抑制作用，造成发酵原料累积产甲烷量降低，促使优势产甲烷菌群由嗜乙酸型逐渐向氢营养型转变。更多还原

【Abstract】 【Objective】Study the effect of ammonia nitrogen mass concentration on methane production characteristics and methanogens community by anaerobic co-fermentation of chicken manure and corn straw. 【Methods 】Different ammonia nitrogen mass concentrations of 1 500,3 000,4 500,and 6 000 mg/L were set up for mesothermal anaerobic fermentation experiments by adding external nitrogen sources using a mixture of chicken manure and corn straw as fermentation raw materials,and no added nitrogen sources as control. The methane production characteristics and changes in methanogens communities of different treatments were measured and analyzed. 【Results】No significant inhibition was found when ammonia nitrogen mass concentration was less than 3 000 mg/L. While significant inhibition was found with the delay of methane production peak,decrease of material cumulative methane production,increase of free ammonia(FAN) content,and accumulation of volatile fatty acid(VFAs) when ammonia nitrogen mass concentration was greater to or equal to 3 000 mg/L.When the ammonia nitrogen mass concentrations were 3 000,4 500,and 6 000 mg/L,the material cumulative methane production was 119.50,96.60,and 64.52 mL/gVS,respectively,which was 16.66%,32.67%,and 55.03% lower than the control. Among them,the ammonia nitrogen mass concentration of 6 000 mg/L exceeded IC50(semi inhibitory concentration).The acetate-utilizing Methanosaeta was the dominant methanogens when ammonia nitrogen mass concentration was less than3 000 mg/L. With the increase of ammonia nitrogen mass concentration to 3 000 mg/L or more,methanogens community changed. The relative abundance of Methanosaeta decreased while high ammonia tolerance and hydrogen-fermentation Methanosarcina and Methaanoculleus increased. 【Conclusion】When ammonia nitrogen mass concentration in the co-digestion of chicken manure and corn straw system was higher than 1 500 mg/L,the inhibition effect was found on acetate-utilizing methanogens,resulted in the decrease of material cumulative methane production. And the dominant methanogens changed from acetate-utilizing to hydrogen-utilizing.更多还原