微生物菌剂对猪粪堆肥中细菌群落结构的影响

以猪粪和小麦秸秆做堆肥试验,处理组添加外源微生物菌剂,利用常规方法对堆肥样品进行理化性状测定,采用高通量测序技术分析堆肥过程中细菌群落特征。理化性状测定结果表明: 添加外源菌剂可延长堆肥高温时间,降低堆肥发酵末期的pH,增加全氮含量,加快C/N的下降。主成分分析表明: 外源菌剂影响堆肥样品细菌群落的稳定性。门分类水平上,厚壁菌门、变形菌门和绿弯菌门的相对丰度在处理组中较高;纲分类水平上,梭状芽孢杆菌纲、α-变形菌纲和γ-变形菌纲在处理组的升温期和高温期相对丰度增加;科分类水平上,小单孢菌科和梭状芽孢杆菌纲的消化链球菌科、梭菌科以及盐厌氧菌科的相对丰度在处理组的升温期和高温期均呈上升趋势。Pearson相关性分析表明,盐胞菌属与外源菌剂呈显著正相关,而氨苄芽孢杆菌属与外源菌剂呈显著负相关。研究表明,猪粪堆肥中添加外源菌剂可使堆肥的理化性质和细菌群落结构均发生显著变化。

Effects of microbial agents on bacterial community composition during swine manure composting

The process of swine manure and wheat straw aerobic composting was examined, with exogenous microbial agents being added in treatment group. The physicochemical properties were measured by conventional methods, and bacterial community characteristics were investigated by high throughput sequencing analysis. Exogenous microbial agents increased high-temperature duration, reduced pH value at the end of fermentation stage, augmented total nitrogen content, reduced C/N ratio. Results from principal component analysis showed that microbial agents affected the stability of bacterial community during composting. At the phylum level, the relative abundance of Firmicutes, Proteobacteria, and Chloroflexi was higher in the treatment group. At the class level, the relative abundance of Clostridia, Alphaproteobacteria, and Gammaproteobacteria in the treatment group were higher at the mesophilic and thermophilic phases. At the family level, Peptostreptococcaceae, Clostridiaceae_1, and Halanaerobiaceae of the Clostridia and Micromonosporaceae in the treatment group were higher at the mesophilic and thermophilic phases. Halocella was significantly positively correlated with exogenous microbial agents, while Ammoniibacillus was significantly negatively correlated with it. It suggested that microbial agents significantly changed the physicochemical properties and bacterial community structure during swine composting.