摘要： 为了加快玉米秸秆腐熟，推动秸秆废弃物循环利用，开展了以玉米秸秆为主要原料的好氧发酵堆肥试验。利用常规方法对不同发酵时期堆料的理化性状进行测定，采用宏基因组测序技术和生物信息学方法对堆体细菌菌群进行多样性分析和物种分类。理化性状测定结果表明，好氧发酵期间堆体温度能够快速升高并维持在55.0℃以上，堆体含水量、有机物含量和C/N逐渐下降，w （C）/w （N）在建堆和前3次翻堆时均较高，后2次翻堆时大幅下降，pH值、E4/E6先下降后上升；宏基因组结果表明，玉米秸秆好氧堆肥中细菌菌群存在多样性；由Simpson指数和Shannon指数可知，第5次翻堆（CS5）细菌群落多样性最高，前3次翻堆（CS1、CS2和CS3）多样性差异不明显，第4次翻堆（CS4）的群落多样性最低。对6个发酵时期的OTU进行物种分类，所检测到的细菌门类、目类和属类在不同发酵时期的种类和丰度不同，表现出明显的群落演替现象。物种分类结果表明，玉米秸秆好氧发酵期间的主要优势门类为厚壁菌门、变形菌门、拟杆菌门和放线菌门；共享的主要优势目类为芽孢杆菌目、梭菌目、黄色单胞菌目、嗜热厌氧杆菌目、根瘤菌目、假单胞菌目和厌氧绳菌目；共享的主要属为Povalibacter、梭状芽孢杆菌属、芽孢杆菌属、赖氨酸芽孢杆菌属、嗜热脲芽孢杆菌属、假单胞菌属和Chryseolinea。其中，变形菌门黄色单胞菌目的Povalibacter、厚壁菌门芽孢杆菌目的梭状芽孢杆菌属和赖氨酸芽孢杆菌属以及拟杆菌门噬纤维素菌目的Chryseolinea尚未见与玉米秸秆木质纤维素降解有关的报道，有望从这些菌属中分离出加快玉米秸秆好氧发酵堆肥进程的新菌种。

关键词: 玉米秸秆, 细菌群落多样性, 宏基因组法, 好氧发酵, 不同发酵时期, 理化性状

Abstract: To accelerate the corn straw decomposition and promote straw waste recycling,the aerobic fermentation composting experiment was carried out using corn straw as the main raw materials. The physicochemical properties of windrow in different fermentation periods were measured by conventional methods,while the diversity analysis and species classification of microbial flora were carried out by metagenomic sequencing and bioinformatics method. The results of physicochemical properties showed that during the aerobic fermentation,the windrow temperature could rise quickly and maintain at above 55.0℃,the water content,organic matter and C/N ratio gradually decreased,and w (C)/w (N) was higher in building heap and in the first three turns and it dropped sharply at the last two turns,while the pH value and E4/E6 ratio decreased firstly and then increased. Metagenomic results showed that bacteria diversity existed in aerobic composting with corn straw. From the Simpson and Shannon index,the bacteria community diversity at the fifth turning(CS5)appeared to be the highest with subtle differences of the first three times(CS1,CS2 and CS3),while the diversity at the fourth turning(CS4)being the lowest. According to the species classification with OTU in 6 different fermentation periods,the species and abundances were different on phyla,orders and genera level,showing obvious community succession. Species classification results showed that Firmicutes, Proteobacteria,Bacteroidetes and Actinobacteria were the dominant groups on the phylum level.Bacillales,Clostridiales,Xanthomonadales,Thermoanaerobacterales,Rhizobiales,Pseudomonadales and Anaerolineales were main sharing groups on the order level. Povalibacter, Clostridium Ⅲ, Bacillus, Lysinibacillus, Ureibacillus, Pseudomonas and Chryseolinea were the main genera in the whole aerobic fermentation periods. Povalibacter belongs to Xanthomonadales of Proteobacteria,Clostridium Ⅲ and Lysinebacillus belong to Clostridiales of Firmicutes,and Chryseolinea belongs to Cytophagales of Bacteroidetes,they have not being reported to associate with lignocellulose degradation,it was expected to isolate new strains from these genera and accelerate the process of aerobic composting.

Key words: Corn straw (CS), Bacterial community diversity, Metagenomics, Aerobic fermentation, Different fermentation periods, Physicochemical properties

中图分类号: 

• Q939.96