好氧堆肥微生物代谢多样性及其细菌群落结构

好氧堆肥是农业废弃物无害化处理和资源化利用的一条有效途径.为了探究好氧堆肥过程中微生物群落的代谢特征和细菌群落演替现象，了解起关键作用的微生物菌群，通过筛选强降解菌种改善堆肥工艺、提高堆肥效率，采用Biolog法和宏基因组法分析了玉米秸秆和牛粪联合好氧堆肥过程中微生物的碳源代谢能力和细菌群落多样性.结果表明:在第2次翻堆（第14天）时，微生物利用碳源的能力最强，初次建堆时（0 d）和其余翻堆时（第8、20、26天）次之，发酵结束时（第34天）最弱.Simpson、Shannon-Wiener和McIntosh多样性指数表明，建堆时及翻堆时的菌群优势度、丰富度和均匀度均极显著优于好氧堆肥结束.不同好氧发酵时间的微生物群落对同一碳源代谢有差异，同一好氧发酵时间微生物群落对不同碳源的利用率不同.糖类、酸类和醇类是区分好氧堆肥不同时间微生物碳源利用差异的敏感碳源.好氧堆肥不同时间细菌的种类和丰度不同，共享的优势菌门有厚壁菌门（Firmicutes）、变形菌门（Proteobacteria）、拟杆菌门（Bacteroidetes）、绿弯菌门（Chloroflexi）、放线菌门（Actinobacteria）和浮霉菌门（Planctomycetes），在第0、8、14、20、26、34天这6个时间内它们的相对丰度之和分别达90.27%、90.34%、94.26%、84.21%、84.31%和77.61%，且6种门类在不同发酵时间的丰度表达存在消长变化状态.研究显示，参与好氧堆肥不同时间的微生物群落在碳源代谢能力上存在多样性，在细菌菌群的种类和丰度上也存在多样性. 

Microbial Metabolism Diversity and Bacterial Flora Structure during Aerobic Composting

The aerobic fermentation composting is an effective way for the harmless disposal and resource utilization of agricultural waste. The present study is aimed at screening effectively degrading strains for improving composting process by exploring metabolic characteristics and microbial community and understanding the dominant bacteria during aerobic fermentation process. Biolog and metagenomic methods were used to analyze the carbon source metabolic capacity of microorganisms and bacterial community diversity for aerobic fermentation compost with corn stalk and cow manure. The results showed that the ability of carbon sources utilization for microorganisms was the strongest at the second turning (the 14^th day), and the early establishment of a composting (0 d) was in the second place, such as the same with the other periods of turning (the 8^th, 20^th and 26^th day), and the weakest one was at the end of aerobic fermentation (the 34^th day). The diversity indices of Simpson, Shannon and McIntosh showed that dominance, richness and evenness for microbial community in the early establishment of a composting and the different turnover composting period were significantly better than those at the end of fermentation. The same carbon source metabolism differed to microbial communities at the different fermentation time, and the microbial community had different utilization of different carbon sources at the same fermentation period. Carbohydrates, acids and alcohols were sensitive carbon sources that could differentiate utilization variance of the microbe carbon sources from different time of aerobic compost. The species and abundances of bacteria were different at different periods of aerobic fermentation. Firmicutes, Proteobacteria, Bacteroidetes, Chloroflexi, Actinobacteria and Planctomycetes were the dominant groups on the phylum level. The sum of their relative abundances in the six periods were respectively 90.27%, 90.34%, 94.26%, 84.21%, 84.31% and 77.61%, and the abundances of six phyla existed changing state of growth and decline during different fermentation. It showed that the microbial communities involved in the aerobic compost at different time had diversity in carbon source metabolism, and their bacterial flora structure was different in species and abundance.