Publication Date:
2019
Description:
Abstract
Bacterial communities in sediments of the Caiwei Seamount, a typical guyot located in the northwest Pacific Ocean, were investigated. A total of 727,879 16S ribosomal RNA gene sequences were retrieved from 8 sediment samples of the top (mean depth = 1407 m) and the base (mean depth = 5525 m) of the guyot through pyrosequencing of V6 hypervariable region, and clustered into 32,844 Operational Taxonomic Units. Abundant‐weighted UniFrac metric partitioned bacterial assemblies into two categories (the top community and the base community) by principal coordinates analysis, consisting with the grouping of sampling stations by environmental variables. Differences in depth and physicochemical properties of the surrounding environment (e.g. concentrations of dissolved oxygen and geochemical elements) between the top and the base of the guyot may cause this partition of bacterial communities, whereas the typical fluid flow around the guyot may potentially contribute to the bacterial dispersal and environmental homogeneity along the same layer, resulting in the similarity of bacterial community structure within the same region (the top or the base). The surface sediment on the top of the guyot harbored the bacterial communities with greater diversity and evenness, represented by Gamma‐ and Deltaproteobacteria involved in sulfur cycling. At the base of the guyot, Gammaproteobacteria related to sulfur‐oxidizing and Chloroflexi functioning in the decomposition of refractory organic matters dominated, suggesting the redox condition at the interface of the sediment and the water can influence bacteria‐mediated elemental cycling, eventually shaping the physicochemical and geological characteristics of a guyot.
Print ISSN:
2169-8953
Electronic ISSN:
2169-8961
Topics:
Biology
,
Geosciences
