Study On Community Diversity And Function Of Common Microbe In Vermicomposting Of Urban Sludge

Under the influence of different environmental factors in different batches of vermicompost as research object,using ? llumina Mi Seq high-throughput sequencing technologies to determine microbial screening methods and principles of screening,research in common microbial community structure,abundance,differences between groups,evolutionary relationships and functions.Explore different temperature,different organic matter content of the sludge particle size and initial sludge under different in the different groups of different stages of the earthworm compost were exist and has the advantage degree,can maintain stable worm composting ecosystem at the core of the bacteria,and in the different stages of different groups there were significant variation characteristics,its relative abundance often show from scratch and there is a certain advantage,to promote the system in the process of biochemical degradation of organic matter and ammonification and nitrification bacteria have particular significance significant change.Based on the contribution of core bacteria and significantly changing bacteria to common microorganisms,evolutionary relationship between them and their correlation with environmental factors,the community diversity and function of common microorganisms in earthworm composting of urban sludge were discussed from the biochemical and molecular levels.The main results are as follows:(1)According to the screening principles of common microorganisms in the earthworm composting system of urban sludge: co-existence,dominance,significance,variability and unity,the common microbial species are determined as follows: the phylum includes Proteobacteria?Bacteroidetes?Actinobacteria?norank?f?Saprospiraceae,the genus includes Thauera ? Zoogloea ? norank?f?Sphingobacteriales ? Aquabacterium ?norank?f?Draconibacteriaceae ? Arcobacter ? Sediminibacterium ? norank?f?AKYH767 ?Fluviicola?norank?f?Chitinophagaceae?Thermomonas?Filimonas?Pseudoxanthomonas?Mucilaginibacter?norank?o?JG30?KF?CM45.(2)RDA analysis of common microorganisms,environmental factors and sludge samples obtained from three batches of earthworm composts showed that Proteobacteria in the phylum level participated in the process of organic matter degradation,while Bacteroidetes and Actinobacteria were positively correlated with nitrification in organic nitrogen mineralization.At the genus level,Filimonas,norank?f?Chitinophagaceae and Mucilagimibacter were involved in nitrification,Fluviicola and norank?f?Sphingobacteriales were positively correlated with ammoniation,and Zoogloea and Sediminibacter were involved in organic matter degradation.(3)The variation trend of the obtained common microorganisms in different environmental factor groups with the composting process was consistent,and the structure system of common microbial community was constructed based on the average value of their relative abundance.On the whole,the variation trend of all common microorganisms was that the relative abundance of composting decreased sharply in the early stage and fluctuated in the later stage.The results showed that the function of microorganisms in the organic matter degradation stage was relatively concentrated,and the promotion of ammoniation and nitrification process in the later stage included the influence of various microorganisms on the biochemical process of earthworm composting through the synergistic creation of suitable habitat.The microorganisms that played a synergistic role were also susceptible to the change of environmental factors.(4)The common microbial functions of earthworm composting in urban sludge were classified.The results showed that the dominant phyla and genera had important significance for the formation of the community structure and function of urban sludge,and had been fully adapted to the ecological environment of earthworm composting.Although common microbial quantity is less,but still contains organic matter,nitrogen,sulfate,iron metabolism and other metabolic function,for urban sludge stabilization and humification process can make outstanding contributions,from another Angle shows that these communities on the sludge micro ecological environment have a better ability to adapt,able to fully accommodate the earthworm compost selectivity of microbial communities.