Abundance and Diversity of Bacteria in XXXX Minimum Drinking Water Reservoir Sediments Studied by Quantitative PCR and Pyrosequencing.

@entity26 @entity1568 @entity3794
UNASSIGNED: Reservoir sediment is one of the most stressful environments for microorganisms due to periodically @entity26 minimum conditions. In this study, the abundance and composition of bacteria associated with sediments from three drinking water reservoirs (Zhoucun, ZCR; Shibianyu, SBYR; and Jinpen, JPR) were investigated by quantitative polymerase chain reaction and 16S rRNA-based 454 pyrosequencing. The results of physico-chemical analysis of sediments showed that the organic matter and total @entity1568 were significantly higher in ZCR as compared to JPR (P   <   0.01). The bacterial abundance was 9.13   *   10(6), 1.14   *   10(7), and 6.35   *   10(6)  copies/ng DNA in sediments of SBYR, ZCR, and JPR, respectively (P   <   0.01). The pyrosequencing revealed a total of 9,673 operational taxonomic units, which were affiliated with 17 phyla. The dominant phylum was Firmicutes (56.83  %) in JPR; whereas, the dominance of Proteobacteria was observed in SBYR with 40.38  % and ZCR with 39.56  %. The Shannon-Wiener diversity (H') was high in ZCR; whereas, Chao 1 @entity3794 was high in SBYR. The dominant genera were Clostridium with 42.15  % and Bacillus with 20.44  % in JPR. Meanwhile, Dechloromonas with14.80  % and Smithella with 7.20  % were dominated in ZCR, and Bacillus with 45.45  % and Acinetobacter with 5.15  % in SBYR. The heat map profiles and redundancy analysis indicated substantial differences in sediment bacterial community composition among three reservoirs. Moreover, it appears from the results that physico-chemical variables of sediments including pH, organic matter, total @entity1568 , and available phosphorous played key roles in shaping the bacterial community diversity. The results obtained from this study will broaden our understanding on the bacterial community structure of sediments in @entity26 minimum and stressful freshwater environments.
