【摘要】 对虾循环水养殖因污染排放少、经济效益高而正在逐步取代土塘养殖,成为高效养殖模式发展的方向,了解养殖系统的细菌群落结构特征对于病害控制和养殖工艺改进具有重要意义。采用细菌16S rRNA基因扩增子焦磷酸测序,比较了循环养殖水体、生物膜与土塘养殖水环境中的细菌群落结构差异。结果表明,循环养殖水体、生物膜与土塘水体的细菌群落结构差异明显,且循环养殖水体中细菌多样性最高。蓝细菌门(Cyanobacteria)和放线菌门(Actinobacteria)在土塘水体所占比例较高;循环养殖系统中α-变形菌纲(Alphaproteobacteria)在水体中占优势,而β-变形菌纲(Betaproteobacteria)和拟杆菌门(Bacteroidetes)为生物膜中的优势种群。相似度分析表明,有11个分类操作单元(Operational taxonomic units,OTUs)对细菌群落差异贡献较大,累积贡献率达35.14%。这些OTUs的分类归属:腐螺旋菌科(Saprospiraceae)、红杆菌科(Rhodobacteraceae)和放线菌目的 ACK-M1科各2个,聚球藻科(Synechococcaceae)、暖绳菌科(Caldilineaceae)各1个,另有3个分属于β-变形菌纲、黄杆菌纲(Flavobacteria)和鞘脂单胞菌目(Sphingomonadales)中的未知科。此外,与氮循环密切相关的亚硝化单胞菌科(Nitrosomonadaceae)和硝化螺旋菌科(Nitrospiraceae)是生物膜中的主要类群。研究初步揭示了对虾循环系统优于土塘养殖的微生物生态基础。更多还原

【Abstract】 Recirculating aquaculture system( RAS) has gradually replaced the traditional earthen pond(Earth) for shrimp cultivation because of its less pollution and higher economical benefit. A comprehensive knowledge on bacterial community structure is necessary for disease control and process improvement. In this paper amplicon pyrosequencing of 16 S rRNA gene was used to compare the bacterial community structure among recirculating aquaculture system(water and biofilm) and earthen pond( water). The results showed that the bacterial communities were distinct among Earth water,RAS water and biofilm,with the highest alpha-diversity in RAS water.Cyanobacteria and Actinobacteria were the predominant phyla in earthen pond. In contrast,Alphaproteobacteria was the highest in the RAS water,while Betaproteobacteria and Bacteroidetes were the dominant phyla in the RAS biofilm. Similarity percentage( SIMPER)analysis identified 11 OTUs that cumulatively contributed to 35.14% dissimilarity of the bacterial community. These taxa were affiliated with Saprospiraceae,Rhodobacteraceae,ACK-M1 and Synechococcaceae,Caldilineaceae,Betaproteobacteria,Sphingomonadales,Flavobacteria. At a finer resolution,the members of family Nitrosomonadaceae and Nitrospiraceae,which contribute to denitrification and nitrification,were dramatically higher in RAS biofilm than in waters. Overall,this work provides microbial ecological evidences for the advantages of recirculating aquaculture system over earthen pond.更多还原