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Title: Spatial and successional dynamics of microbial biofilm communities in a grassland stream ecosystem

Abstract

Biofilms represent a metabolically active and structurally complex component of freshwater ecosystems. Ephemeral prairie streams are hydrologically harsh and prone to frequent perturbation. Elucidating both functional and structural community changes over time within prairie streams provides a general understanding of microbial responses to environmental disturbance. In this study, we examined microbial succession of biofilm communities at three sites in a third-order stream at Konza Prairie over a 2- to 64-day period. Microbial abundance (bacterial abundance, chlorophyll a concentrations) increased and never plateaued during the experiment. Net primary productivity (net balance of oxygen consumption and production) of the developing biofilms did not differ statistically from zero until 64 days suggesting a balance of the use of autochthonous and allochthonous energy sources until late succession. Bacterial communities (MiSeq analyses of the V4 region of 16S rRNA) established quickly. Bacterial richness, diversity and evenness were high after 2 days and increased over time. Several dominant bacterial phyla (Beta-, Alphaproteobacteria, Bacteroidetes, Gemmatimonadetes, Acidobacteria, Chloroflexi) and genera ( Luteolibacter, Flavobacterium, Gemmatimonas, Hydrogenophaga) differed in relative abundance over space and time. Bacterial community composition differed across both space and successional time. Pairwise comparisons of phylogenetic turnover in bacterial community composition indicated that early-stage succession (≤16 days)more » was driven by stochastic processes, whereas later stages were driven by deterministic selection regardless of site. Finally, our data suggest that microbial biofilms predictably develop both functionally and structurally indicating distinct successional trajectories of bacterial communities in this ecosystem.« less

Authors:
 [1];  [2];  [3];  [4];  [4]
  1. Kansas State Univ., Manhattan, KS (United States). Division of Biology; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division
  2. Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Biological Sciences Division
  3. Kansas State Univ., Manhattan, KS (United States). Division of Biology; Univ. of Illinois, Urbana-Champaign, Urbana, IL (United States). Department of Plant Biology
  4. Kansas State Univ., Manhattan, KS (United States). Division of Biology
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1346662
Grant/Contract Number:
AC05-00OR22725; AC06-76RL01830
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Molecular Ecology
Additional Journal Information:
Journal Volume: 25; Journal Issue: 18; Journal ID: ISSN 0962-1083
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 59 BASIC BIOLOGICAL SCIENCES; algae; bacteria; commmunity ecology; DNA barcoding; microbial biology

Citation Formats

Veach, Allison M., Stegen, James C., Brown, Shawn P., Dodds, Walter K., and Jumpponen, Ari. Spatial and successional dynamics of microbial biofilm communities in a grassland stream ecosystem. United States: N. p., 2016. Web. doi:10.1111/mec.13784.
Veach, Allison M., Stegen, James C., Brown, Shawn P., Dodds, Walter K., & Jumpponen, Ari. Spatial and successional dynamics of microbial biofilm communities in a grassland stream ecosystem. United States. doi:10.1111/mec.13784.
Veach, Allison M., Stegen, James C., Brown, Shawn P., Dodds, Walter K., and Jumpponen, Ari. 2016. "Spatial and successional dynamics of microbial biofilm communities in a grassland stream ecosystem". United States. doi:10.1111/mec.13784. https://www.osti.gov/servlets/purl/1346662.
@article{osti_1346662,
title = {Spatial and successional dynamics of microbial biofilm communities in a grassland stream ecosystem},
author = {Veach, Allison M. and Stegen, James C. and Brown, Shawn P. and Dodds, Walter K. and Jumpponen, Ari},
abstractNote = {Biofilms represent a metabolically active and structurally complex component of freshwater ecosystems. Ephemeral prairie streams are hydrologically harsh and prone to frequent perturbation. Elucidating both functional and structural community changes over time within prairie streams provides a general understanding of microbial responses to environmental disturbance. In this study, we examined microbial succession of biofilm communities at three sites in a third-order stream at Konza Prairie over a 2- to 64-day period. Microbial abundance (bacterial abundance, chlorophyll a concentrations) increased and never plateaued during the experiment. Net primary productivity (net balance of oxygen consumption and production) of the developing biofilms did not differ statistically from zero until 64 days suggesting a balance of the use of autochthonous and allochthonous energy sources until late succession. Bacterial communities (MiSeq analyses of the V4 region of 16S rRNA) established quickly. Bacterial richness, diversity and evenness were high after 2 days and increased over time. Several dominant bacterial phyla (Beta-, Alphaproteobacteria, Bacteroidetes, Gemmatimonadetes, Acidobacteria, Chloroflexi) and genera (Luteolibacter, Flavobacterium, Gemmatimonas, Hydrogenophaga) differed in relative abundance over space and time. Bacterial community composition differed across both space and successional time. Pairwise comparisons of phylogenetic turnover in bacterial community composition indicated that early-stage succession (≤16 days) was driven by stochastic processes, whereas later stages were driven by deterministic selection regardless of site. Finally, our data suggest that microbial biofilms predictably develop both functionally and structurally indicating distinct successional trajectories of bacterial communities in this ecosystem.},
doi = {10.1111/mec.13784},
journal = {Molecular Ecology},
number = 18,
volume = 25,
place = {United States},
year = 2016,
month = 9
}

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