全量化收集粪污厌氧发酵失稳过程中微生物群落动态变化及生态集群组装模式OACSTPCD

Through high-throughput sequencing technology,we analyzed the dynamic changes of microbial communities at stability,inhibition and collapse stage of anaerobic fermentation of fully-quantified manure,combined with the construction of microbial interaction network,and identified the key ecological clusters and assembly modes of the network,so as to provide theoretical basis and data support for the stable operation of fully quantified manure biogas projects.The results showed that:(1)At the bacterial phylum level,Firmicutes,Bacteroidetes and Proteobacteria were the dominant phyla,with the relative abundance of 96%.(2)At the bacterial genus level,genera with high relative abundance were Ruminiclostridium,Clostridium_sensu_stricto_1,etc.(3)At the level of archaeal genera,Methanobrevibacter,Methanosphaera and Methanoculleus were the dominant genera,with the relative abundance of 96.5%.(4)The microbial interaction network analysis revealed that the functional clusters in the anaerobic fermentation process of manure were mainly divided into three modules(module 1～3),and the microbial community would make stressful adjustments when the anaerobic fermentation was inhibited.During the stable gas production period,module 1 dominates the anaerobic fermentation system with good synergy between hydrolytic acidifying bacteria and methanogenic bacteria,and stable hydrolysis and acid production without obvious accumulation of small molecule volatile acids.During the gas-producing collapse period,the relative abundance of modules 2 and 3 increased dramatically and occupied the ecological niche of module 1.The microorganisms mitigated the stress of small-molecule volatile acids and ammonia nitrogen by increasing the relative abundance of volatile organic acid(acetic acid and propionic acid)oxidizing bacteria and the ability of acidophilic methanogenic bacteria.