Bacterial Community Composition in Three Freshwater Reservoirs of Different Alkalinity and Trophic Status

Abstract

In order to investigate the factors controlling the bacterial community composition (BCC) in reservoirs, we sampled three freshwater reservoirs with contrasted physical and chemical characteristics and trophic status. The BCC was analysed by 16S rRNA gene amplicon 454 pyrosequencing. In parallel, a complete dataset of environmental parameters and phytoplankton community composition was also collected. BCC in the analysed reservoirs resembled that of epilimnetic waters of natural freshwater lakes with presence of Actinobacteria, Alpha- and Betaproteobacteria, Cytophaga–Flavobacteria–Bacteroidetes (CFB) and Verrucomicrobia groups. Our results evidenced that the retrieved BCC in the analysed reservoirs was strongly influenced by pH, alkalinity and organic carbon content, whereas comparatively little change was observed among layers in stratified conditions.

Diversity of Bacteria in Lakes with Different Chlorophyll Content and Investigation of Their Respiratory Activity through a Long-Term Microcosm Experiment

“…Ziros summer (ZS, oligotrophic) and Pamvotis winter (PW, mesotrophic) samples occupied separate branches of the cluster with PW being the most dissimilar. These results differ from previous studies, which showed mesotrophic waters to exhibit similarities either to oligotrophic or to eutrophic waters [17,18]. The complete differentiation of the bacterial community in mesotrophic PW from the other samples supports the suggestion that extreme water physicochemical conditions, like the low temperatures recorded in this study, can shape communities and select taxa that cope well with harsh environment [59].…”

“…Indeed, a study in several lakes, rivers and reservoirs in Portugal indicated higher similarities for oligotrophic and mesotrophic water bodies compared to eutrophic/hypereutrophic [17]. However, a different pattern was revealed in reservoirs in Belgium where mesotrophic and eutrophic water bodies exhibited more similarities in respect to an oligotrophic reservoir [18]. A core bacterioplankton community was found across an oligotrophic to urban-eutrophic gradient in Lake Michigan [19].…”

Cyanobacterial harmful algal blooms are a biological disturbance to Western Lake Erie bacterial communities

“…Several other studies have documented that bacterial communities respond to shifts in substrates available within the dissolved organic carbon pool during both freshwater and marine blooms (Lau et al ., ; Teeling et al ., ; Yang et al ., ). Alternatively, pH is known to be a major influence on bacterial community composition in soil (Lauber et al ., ) and freshwater systems (Lindstrom et al ., ; Llirós et al ., ). Therefore, the bloom may have actually influenced the composition of nc‐bacterial communities by changing the lake's pH.…”

Microscale decoupling of sediment oxygen consumption and microbial biomass in an oligotrophic lake

“…We further tested if patterns in bacterial diversity could explain differences in oxygen consumption. In general, the community data were consistent with expected patterns for oligotrophic freshwater sediments with terrestrial inputs, with a dominance of, in decreasing order of abundance, Betaproteobacteria, Alphaproteobacteria, Gammaproteobacteria, Actinobacteria, Deltaproteobacteria, Clostridia, Sphingobacteria, Planctomycetacia, Bacilli and Acidobacteria (Besemer et al ., ; Llirós et al ., ). We initially hypothesised that high oxygen consumption rates would be associated with high bacterial diversity.…”