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Jackson AC, Jorna J, Chaston JM, Adams BJ. Glacial Legacies: Microbial Communities of Antarctic Refugia. BIOLOGY 2022; 11:biology11101440. [PMID: 36290344 PMCID: PMC9598129 DOI: 10.3390/biology11101440] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/26/2022] [Accepted: 09/30/2022] [Indexed: 11/06/2022]
Abstract
In the cold deserts of the McMurdo Dry Valleys (MDV) the suitability of soil for microbial life is determined by both contemporary processes and legacy effects. Climatic changes and accompanying glacial activity have caused local extinctions and lasting geochemical changes to parts of these soil ecosystems over several million years, while areas of refugia may have escaped these disturbances and existed under relatively stable conditions. This study describes the impact of historical glacial and lacustrine disturbance events on microbial communities across the MDV to investigate how this divergent disturbance history influenced the structuring of microbial communities across this otherwise very stable ecosystem. Soil bacterial communities from 17 sites representing either putative refugia or sites disturbed during the Last Glacial Maximum (LGM) (22-17 kya) were characterized using 16 S metabarcoding. Regardless of geographic distance, several putative refugia sites at elevations above 600 m displayed highly similar microbial communities. At a regional scale, community composition was found to be influenced by elevation and geographic proximity more so than soil geochemical properties. These results suggest that despite the extreme conditions, diverse microbial communities exist in these putative refugia that have presumably remained undisturbed at least through the LGM. We suggest that similarities in microbial communities can be interpreted as evidence for historical climate legacies on an ecosystem-wide scale.
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Affiliation(s)
- Abigail C. Jackson
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
- Correspondence: (A.C.J.); (J.J.)
| | - Jesse Jorna
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
- Correspondence: (A.C.J.); (J.J.)
| | - John M. Chaston
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT 84602, USA
| | - Byron J. Adams
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
- Monte L. Bean Museum, Brigham Young University, Provo, UT 84602, USA
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2
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Çelik I, Keskin E. Revealing the Microbiome of Four Different Thermal Springs in Turkey with Environmental DNA Metabarcoding. BIOLOGY 2022; 11:biology11070998. [PMID: 36101376 PMCID: PMC9311576 DOI: 10.3390/biology11070998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/18/2022] [Accepted: 06/20/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary The physicochemical conditions of thermal springs are one of the most significant barriers for detecting microbial life. According to the findings of various studies, high-throughput DNA sequencing technology can be utilized to perform more precise and detailed microbiome assessments. The main goal of this paper was to determine the microbiome in a thermal spring by metabarcoding environmental DNA obtained from four different sources and revealing how temperature and chemical composition affect the microbiome. This research also aimed to gather information that will aid in determining the best gene region and bioinformatic pipeline. The findings revealed a link between four different thermal springs’ physicochemical parameters and microbial composition and we found various manipulable steps in this study. This research is also first comprehensive thermal spring metabarcoding study conducted in Turkey. Abstract One of the most significant challenges for detecting microbial life in thermal springs by conventional techniques such as culturing is these places’ physicochemical (temperature, heavy metal content, pH, etc.) conditions. Data from several studies suggest that high-throughput DNA sequencing technologies can be used to perform more accurate and detailed microbiome analyses. The primary aim of this paper was to determine the microbiome in the thermal source by metabarcoding environmental DNA isolated from four different sources and reveal the reflection of differences caused by temperature and chemical content on the microbiome. DNA was extracted from water filtered with enclosed filters and using the Illumina high-throughput sequencing platform, V3 and V4 regions of the 16S rRNA gene were sequenced. The results showed a correlation between physicochemical conditions and microorganism composition of four different thermal springs. Springs with extremely high temperature (89–90 °C) were dominated by hyperthermophiles such as Hydrogenobacter and Thermus, while a spring with a high temperature (52 °C) was dominated by thermophiles such as Thermoanaerobaculum and Desulfurispora, and a spring with a low temperature (26 °C) and high salinity was dominated by halophiles and sulfur-oxidizers such as Hydrogenovibrio and Sulfirimonas. With this research, we observed many manipulable steps according to the work of interest. This study sought to obtain data that will help decide the right gene region and choose the optimal bioinformatic pipeline.
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Affiliation(s)
- Işılay Çelik
- Biotechnology Institute, Ankara University, Ankara 06135, Turkey;
- Evolutionary Genetics Laboratory (eGL), Department of Fisheries and Aquaculture, Agricultural Faculty, Ankara University, Ankara 06135, Turkey
| | - Emre Keskin
- Evolutionary Genetics Laboratory (eGL), Department of Fisheries and Aquaculture, Agricultural Faculty, Ankara University, Ankara 06135, Turkey
- Correspondence:
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3
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Jiang X, Van Horn DJ, Okie JG, Buelow HN, Schwartz E, Colman DR, Feeser KL, Takacs-Vesbach CD. Limits to the three domains of life: lessons from community assembly along an Antarctic salinity gradient. Extremophiles 2022; 26:15. [PMID: 35296937 DOI: 10.1007/s00792-022-01262-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/10/2022] [Indexed: 02/01/2023]
Abstract
Extremophiles exist among all three domains of life; however, physiological mechanisms for surviving harsh environmental conditions differ among Bacteria, Archaea and Eukarya. Consequently, we expect that domain-specific variation of diversity and community assembly patterns exist along environmental gradients in extreme environments. We investigated inter-domain community compositional differences along a high-elevation salinity gradient in the McMurdo Dry Valleys, Antarctica. Conductivity for 24 soil samples collected along the gradient ranged widely from 50 to 8355 µS cm-1. Taxonomic richness varied among domains, with a total of 359 bacterial, 2 archaeal, 56 fungal, and 69 non-fungal eukaryotic operational taxonomic units (OTUs). Richness for bacteria, archaea, fungi, and non-fungal eukaryotes declined with increasing conductivity (all P < 0.05). Principal coordinate ordination analysis (PCoA) revealed significant (ANOSIM R = 0.97) groupings of low/high salinity bacterial OTUs, while OTUs from other domains were not significantly clustered. Bacterial beta diversity was unimodally distributed along the gradient and had a nested structure driven by species losses, whereas in fungi and non-fungal eukaryotes beta diversity declined monotonically without strong evidence of nestedness. Thus, while increased salinity acts as a stressor in all domains, the mechanisms driving community assembly along the gradient differ substantially between the domains.
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Affiliation(s)
- Xiaoben Jiang
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - David J Van Horn
- Department of Biology, MSC03 2020 1UNM, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Jordan G Okie
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, 85287, USA
| | - Heather N Buelow
- Department of Biology, MSC03 2020 1UNM, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Egbert Schwartz
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Daniel R Colman
- Department of Biology, MSC03 2020 1UNM, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Kelli L Feeser
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
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4
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Bastida F, Eldridge DJ, García C, Kenny Png G, Bardgett RD, Delgado-Baquerizo M. Soil microbial diversity-biomass relationships are driven by soil carbon content across global biomes. THE ISME JOURNAL 2021; 15:2081-2091. [PMID: 33564112 PMCID: PMC8245509 DOI: 10.1038/s41396-021-00906-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 01/08/2021] [Accepted: 01/21/2021] [Indexed: 01/31/2023]
Abstract
The relationship between biodiversity and biomass has been a long standing debate in ecology. Soil biodiversity and biomass are essential drivers of ecosystem functions. However, unlike plant communities, little is known about how the diversity and biomass of soil microbial communities are interlinked across globally distributed biomes, and how variations in this relationship influence ecosystem function. To fill this knowledge gap, we conducted a field survey across global biomes, with contrasting vegetation and climate types. We show that soil carbon (C) content is associated to the microbial diversity-biomass relationship and ratio in soils across global biomes. This ratio provides an integrative index to identify those locations on Earth wherein diversity is much higher compared with biomass and vice versa. The soil microbial diversity-to-biomass ratio peaks in arid environments with low C content, and is very low in C-rich cold environments. Our study further advances that the reductions in soil C content associated with land use intensification and climate change could cause dramatic shifts in the microbial diversity-biomass ratio, with potential consequences for broad soil processes.
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Affiliation(s)
- Felipe Bastida
- grid.10586.3a0000 0001 2287 8496CEBAS-CSIC. Department of Soil and Water Conservation, Campus Universitario de Espinardo, 30100 Murcia, Spain
| | - David J. Eldridge
- grid.1005.40000 0004 4902 0432Centre for Ecosystem Studies, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052 Australia
| | - Carlos García
- grid.10586.3a0000 0001 2287 8496CEBAS-CSIC. Department of Soil and Water Conservation, Campus Universitario de Espinardo, 30100 Murcia, Spain
| | - G. Kenny Png
- grid.5379.80000000121662407Department of Earth and Environmental Sciences, Michael Smith Building, The University of Manchester, Oxford Road, Manchester, M13 9PT UK ,grid.59025.3b0000 0001 2224 0361Asian School of the Environment, Nanyang Technological University, 50 Nanyang avenue, Singapore, Singapore 639798
| | - Richard D. Bardgett
- grid.5379.80000000121662407Department of Earth and Environmental Sciences, Michael Smith Building, The University of Manchester, Oxford Road, Manchester, M13 9PT UK
| | - Manuel Delgado-Baquerizo
- grid.15449.3d0000 0001 2200 2355Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Sevilla, Spain
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5
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Gurmessa B, Ashworth AJ, Yang Y, Savin M, Moore PA, Ricke SC, Corti G, Pedretti EF, Cocco S. Variations in bacterial community structure and antimicrobial resistance gene abundance in cattle manure and poultry litter. ENVIRONMENTAL RESEARCH 2021; 197:111011. [PMID: 33774017 DOI: 10.1016/j.envres.2021.111011] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/03/2021] [Accepted: 03/09/2021] [Indexed: 06/12/2023]
Abstract
Cattle manure and poultry litter are widely used as fertilizers as they are excellent sources of nutrients; however, potential adverse environmental effects exist during land applications, due to the release of zoonotic bacteria and antimicrobial resistance (AMR) genes. This study was conducted to understand linkages between physiochemical composition, bacterial diversity, and AMR gene presence of cattle manure and poultry litter using quantitative polymerase chain reaction to enumerate four AMR genes (ermB, sulI, intlI, and blactx-m-32), Illumina sequencing of the 16 S region, and analysis of physical and chemical properties. Principal coordinate analysis of Bray-Curtis distance revealed distinct bacterial community structures between the two manure sources. Greater alpha diversity occurred in cattle manure compared to poultry litter (P < 0.05). Redundancy analysis showed a strong relationship between manure physiochemical and composition and bacterial abundance, with positive relationships occurring among electrical conductivity and carbon/nitrogen, and negative associations for total solids and soluble fractions of heavy metals. Cattle manure exhibited greater abundance of macrolide (ermB) and sulfonamide (sulI) resistant genes. Consequently, fresh cattle manure applications may result in greater potential spread of AMR genes to the soil-water environment (relative to poultry litter) and novel best management strategies (such as composting) may reduce the release of AMR genes to the soil-water environment.
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Affiliation(s)
- Biyensa Gurmessa
- Department of Agriculture, Food and Environmental Sciences, Università Politecnica Delle Marche, Via Brecce Bianche 10, 60131, Ancona, Italy
| | - Amanda J Ashworth
- USDA-ARS, Poultry Production and Product Safety Research Unit, 1260 W. Maple St, Fayetteville, AR, 72701, USA.
| | - Yichao Yang
- Department of Crop, Soil, and Environmental Sciences, University of Arkansas, 115 Plant Science Building, University of Arkansas, Fayetteville, AR, 72704, USA
| | - Mary Savin
- Department of Crop, Soil, and Environmental Sciences, University of Arkansas, 115 Plant Science Building, University of Arkansas, Fayetteville, AR, 72704, USA
| | - Philip A Moore
- USDA-ARS, Poultry Production and Product Safety Research Unit, 1260 W. Maple St, Fayetteville, AR, 72701, USA
| | - Steven C Ricke
- Meat Science & Animal Biologics Discovery Program (MSABD), Department of Animal and Dairy Sciences, University of Wisconsin-Madison, 1933 Observatory Drive, Madison, WI, 53706, USA
| | - Giuseppe Corti
- Department of Agriculture, Food and Environmental Sciences, Università Politecnica Delle Marche, Via Brecce Bianche 10, 60131, Ancona, Italy
| | - Ester Foppa Pedretti
- Department of Agriculture, Food and Environmental Sciences, Università Politecnica Delle Marche, Via Brecce Bianche 10, 60131, Ancona, Italy
| | - Stefania Cocco
- Department of Agriculture, Food and Environmental Sciences, Università Politecnica Delle Marche, Via Brecce Bianche 10, 60131, Ancona, Italy
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6
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Estimating microbial mat biomass in the McMurdo Dry Valleys, Antarctica using satellite imagery and ground surveys. Polar Biol 2020. [DOI: 10.1007/s00300-020-02742-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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7
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Thakur MP, Phillips HRP, Brose U, De Vries FT, Lavelle P, Loreau M, Mathieu J, Mulder C, Van der Putten WH, Rillig MC, Wardle DA, Bach EM, Bartz MLC, Bennett JM, Briones MJI, Brown G, Decaëns T, Eisenhauer N, Ferlian O, Guerra CA, König‐Ries B, Orgiazzi A, Ramirez KS, Russell DJ, Rutgers M, Wall DH, Cameron EK. Towards an integrative understanding of soil biodiversity. Biol Rev Camb Philos Soc 2020; 95:350-364. [PMID: 31729831 PMCID: PMC7078968 DOI: 10.1111/brv.12567] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 10/07/2019] [Accepted: 10/11/2019] [Indexed: 12/25/2022]
Abstract
Soil is one of the most biodiverse terrestrial habitats. Yet, we lack an integrative conceptual framework for understanding the patterns and mechanisms driving soil biodiversity. One of the underlying reasons for our poor understanding of soil biodiversity patterns relates to whether key biodiversity theories (historically developed for aboveground and aquatic organisms) are applicable to patterns of soil biodiversity. Here, we present a systematic literature review to investigate whether and how key biodiversity theories (species-energy relationship, theory of island biogeography, metacommunity theory, niche theory and neutral theory) can explain observed patterns of soil biodiversity. We then discuss two spatial compartments nested within soil at which biodiversity theories can be applied to acknowledge the scale-dependent nature of soil biodiversity.
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Affiliation(s)
- Madhav P. Thakur
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenGelderland, The Netherlands
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
- Institute of Biology, Leipzig UniversityLeipzigSaxony, Germany
| | - Helen R. P. Phillips
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
| | - Ulrich Brose
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
- Institute of Biodiversity, Friedrich Schiller University JenaJenaThuringia, Germany
| | - Franciska T. De Vries
- School of Earth and Environmental Sciences, The University of ManchesterManchesterNorth West England, UK
| | | | - Michel Loreau
- Centre for Biodiversity Theory and Modelling, Theoretical and Experimental Ecology Station, CNRS and Paul Sabatier UniversityMoulisOccitanie, France
| | - Jerome Mathieu
- Sorbonne Université, CNRS, UPECParisÎle-de-France, France
| | - Christian Mulder
- Department BiologicalGeological and Environmental Sciences, University of CataniaCataniaSicily, Italy
| | - Wim H. Van der Putten
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenGelderland, The Netherlands
- Laboratory of NematologyWageningen UniversityWageningenGelderland, The Netherlands
| | - Matthias C. Rillig
- Freie Universität Berlin, Institute of BiologyBerlinGermany
- Berlin‐Brandenburg Institute of Advanced Biodiversity Research (BBIB)BerlinGermany
| | - David A. Wardle
- Asian School for the Environment, Nanyang Technological UniversitySingaporeSingapore
| | - Elizabeth M. Bach
- Department of Biology and School of Global Environmental SustainabilityColorado State UniversityFort CollinsCOUSA
| | - Marie L. C. Bartz
- Center of Functional Ecology, Department of Life SciencesUniversity of CoimbraCoimbraCentro, Portugal
- Universidade Positivo, Rua Professor Pedro Viriato Parigot de SouzaCuritiba Paraná, Brazil
| | - Joanne M. Bennett
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
- Institute of Biology, Martin Luther University Halle‐WittenbergHalle (Saale)Saxony-Anhalt, Germany
| | - Maria J. I. Briones
- Departamento de Ecología y Biología AnimalUniversidad de VigoVigoGalicien, Spain
| | | | - Thibaud Decaëns
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE UMR 5175, CNRS–Université de Montpellier–Université Paul‐Valéry Montpellier–EPHE)MontpellierOccitanie, France
| | - Nico Eisenhauer
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
- Institute of Biology, Leipzig UniversityLeipzigSaxony, Germany
| | - Olga Ferlian
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
- Institute of Biology, Leipzig UniversityLeipzigSaxony, Germany
| | - Carlos António Guerra
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
- Institute of Biology, Martin Luther University Halle‐WittenbergHalle (Saale)Saxony-Anhalt, Germany
| | - Birgitta König‐Ries
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐LeipzigLeipzigSaxony, Germany
- Institute of Computer Science, Friedrich Schiller University JenaJenaThuringia, Germany
| | - Alberto Orgiazzi
- European Commission, Joint Research Centre (JRC), Sustainable Resources DirectorateIspraVareseItaly
| | - Kelly S. Ramirez
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenGelderland, The Netherlands
| | - David J. Russell
- Senckenberg Museum of Natural History GörlitzGoerlitzSaxony, Germany
| | - Michiel Rutgers
- National Institute for Public Health and the EnvironmentBilthovenUtrecht, The Netherlands
| | - Diana H. Wall
- Department of Biology and School of Global Environmental SustainabilityColorado State UniversityFort CollinsCOUSA
| | - Erin K. Cameron
- Faculty of Biological and Environmental SciencesUniversity of HelsinkiHelsinki, Uusimaa, Finland
- Department of Environmental ScienceSaint Mary's UniversityHalifaxNova ScotiaCanada
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8
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Geyer KM, Barrett JE. Unimodal productivity–diversity relationships among bacterial communities in a simple polar soil ecosystem. Environ Microbiol 2019; 21:2523-2532. [DOI: 10.1111/1462-2920.14639] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/20/2019] [Accepted: 04/23/2019] [Indexed: 11/27/2022]
Affiliation(s)
- Kevin M. Geyer
- Department of Natural Resources and the EnvironmentUniversity of New Hampshire Durham New Hampshire USA
- Department of Biological SciencesVirginia Polytechnic Institute and State University Blacksburg Virginia USA
| | - John E. Barrett
- Department of Biological SciencesVirginia Polytechnic Institute and State University Blacksburg Virginia USA
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9
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Niederberger TD, Bottos EM, Sohm JA, Gunderson T, Parker A, Coyne KJ, Capone DG, Carpenter EJ, Cary SC. Rapid Microbial Dynamics in Response to an Induced Wetting Event in Antarctic Dry Valley Soils. Front Microbiol 2019; 10:621. [PMID: 31019494 PMCID: PMC6458288 DOI: 10.3389/fmicb.2019.00621] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 03/12/2019] [Indexed: 11/13/2022] Open
Abstract
The cold deserts of the McMurdo Dry Valleys (MDV), Antarctica, host a high level of microbial diversity. Microbial composition and biomass in arid vs. ephemerally wetted regions are distinctly different, with wetted communities representing hot spots of microbial activity that are important zones for biogeochemical cycling. While climatic change is likely to cause wetting in areas not historically subject to wetting events, the responses of microorganisms inhabiting arid soils to water addition is unknown. The purpose of this study was to observe how an associated, yet non-wetted microbial community responds to an extended addition of water. Water from a stream was diverted to an adjacent area of arid soil with changes in microbial composition and activities monitored via molecular and biochemical methods over 7 weeks. The frequency of genetic signatures related to both prokaryotic and eukaryotic organisms adapted to MDV aquatic conditions increased during the limited 7 week period, indicating that the soil community was transitioning into a typical "high-productivity" MDV community. This work is consistent with current predictions that MDV microbial communities in arid regions are highly sensitive to climate change, and further supports the notion that changes in community structure and associated biogeochemical cycling may occur much more rapidly than predicted.
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Affiliation(s)
- Thomas D Niederberger
- College Earth, Ocean, and Environment, University of Delaware, Lewes, DE, United States
| | - Eric M Bottos
- International Centre for Terrestrial Antarctic Research, School of Science, University of Waikato, Hamilton, New Zealand.,Department of Biological Sciences, Thompson Rivers University, Kamloops, BC, Canada
| | - Jill A Sohm
- Department of Biological Sciences, Wrigley Institute for Environmental Studies, University of Southern California, Los Angeles, CA, United States
| | - Troy Gunderson
- Department of Biological Sciences, Wrigley Institute for Environmental Studies, University of Southern California, Los Angeles, CA, United States
| | - Alex Parker
- Romberg Tiburon Center, San Francisco State University, Tiburon, CA, United States
| | - Kathryn J Coyne
- College Earth, Ocean, and Environment, University of Delaware, Lewes, DE, United States
| | - Douglas G Capone
- Department of Biological Sciences, Wrigley Institute for Environmental Studies, University of Southern California, Los Angeles, CA, United States
| | - Edward J Carpenter
- Romberg Tiburon Center, San Francisco State University, Tiburon, CA, United States
| | - Stephen Craig Cary
- College Earth, Ocean, and Environment, University of Delaware, Lewes, DE, United States.,International Centre for Terrestrial Antarctic Research, School of Science, University of Waikato, Hamilton, New Zealand
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10
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Feeser KL, Van Horn DJ, Buelow HN, Colman DR, McHugh TA, Okie JG, Schwartz E, Takacs-Vesbach CD. Local and Regional Scale Heterogeneity Drive Bacterial Community Diversity and Composition in a Polar Desert. Front Microbiol 2018; 9:1928. [PMID: 30186257 PMCID: PMC6110917 DOI: 10.3389/fmicb.2018.01928] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 07/30/2018] [Indexed: 02/01/2023] Open
Abstract
The distribution of organisms in an environment is neither uniform nor random but is instead spatially patterned. The factors that control this patterning are complex and the underlying mechanisms are poorly understood. Soil microbes are critical to ecosystem function but exhibit highly complex distributions and community dynamics due in large part to the scale-dependent effects of environmental heterogeneity. To better understand the impact of environmental heterogeneity on the distribution of soil microbes, we sequenced the 16S rRNA gene from bacterial communities in the microbe-dominated polar desert ecosystem of the McMurdo Dry Valleys (MDV), Antarctica. Significant differences in key edaphic variables and alpha diversity were observed among the three lake basins of the Taylor Valley (Kruskal-Wallis; pH: χ2 = 68.89, P < 0.001, conductivity: χ2 = 35.03, P < 0.001, observed species: χ2 = 7.98, P = 0.019 and inverse Simpson: χ2 = 18.52, P < 0.001) and each basin supported distinctive microbial communities (ANOSIM R = 0.466, P = 0.001, random forest ratio of 14.1). However, relationships between community structure and edaphic characteristics were highly variable and contextual, ranging in magnitude and direction across regional, basin, and local scales. Correlations among edaphic factors (pH and soil conductivity) and the relative abundance of specific phyla were most pronounced along local environmental gradients in the Lake Fryxell basin where Acidobacteria, Bacteroidetes, and Proteobacteria declined while Deinococcus-Thermus and Gemmatimonadetes increased with soil conductivity (all P < 0.1). Species richness was most strongly related to the soil conductivity gradient present within this study system. We suggest that the relative importance of pH versus soil conductivity in structuring microbial communities is related to the length of edaphic gradients and the spatial scale of sampling. These results highlight the importance of conducting studies over large ranges of key environmental gradients and across multiple spatial scales to assess the influence of environmental heterogeneity on the composition and diversity of microbial communities.
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Affiliation(s)
- Kelli L. Feeser
- Department of Biology, University of New Mexico, Albuquerque, NM, United States
| | - David J. Van Horn
- Department of Biology, University of New Mexico, Albuquerque, NM, United States
| | - Heather N. Buelow
- Department of Biology, University of New Mexico, Albuquerque, NM, United States
| | - Daniel R. Colman
- Department of Biology, University of New Mexico, Albuquerque, NM, United States
| | - Theresa A. McHugh
- Department of Biological Sciences, Colorado Mesa University, Grand Junction, CO, United States
| | - Jordan G. Okie
- School of Life Sciences, School of Earth and Space Exploration, Arizona State University, Tempe, AZ, United States
| | - Egbert Schwartz
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, United States
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11
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Geyer KM, Takacs-Vesbach CD, Gooseff MN, Barrett JE. Primary productivity as a control over soil microbial diversity along environmental gradients in a polar desert ecosystem. PeerJ 2017; 5:e3377. [PMID: 28761776 PMCID: PMC5530992 DOI: 10.7717/peerj.3377] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/04/2017] [Indexed: 11/20/2022] Open
Abstract
Primary production is the fundamental source of energy to foodwebs and ecosystems, and is thus an important constraint on soil communities. This coupling is particularly evident in polar terrestrial ecosystems where biological diversity and activity is tightly constrained by edaphic gradients of productivity (e.g., soil moisture, organic carbon availability) and geochemical severity (e.g., pH, electrical conductivity). In the McMurdo Dry Valleys of Antarctica, environmental gradients determine numerous properties of soil communities and yet relatively few estimates of gross or net primary productivity (GPP, NPP) exist for this region. Here we describe a survey utilizing pulse amplitude modulation (PAM) fluorometry to estimate rates of GPP across a broad environmental gradient along with belowground microbial diversity and decomposition. PAM estimates of GPP ranged from an average of 0.27 μmol O2/m2/s in the most arid soils to an average of 6.97 μmol O2/m2/s in the most productive soils, the latter equivalent to 217 g C/m2/y in annual NPP assuming a 60 day growing season. A diversity index of four carbon-acquiring enzyme activities also increased with soil productivity, suggesting that the diversity of organic substrates in mesic environments may be an additional driver of microbial diversity. Overall, soil productivity was a stronger predictor of microbial diversity and enzymatic activity than any estimate of geochemical severity. These results highlight the fundamental role of environmental gradients to control community diversity and the dynamics of ecosystem-scale carbon pools in arid systems.
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Affiliation(s)
- Kevin M. Geyer
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, USA
| | | | - Michael N. Gooseff
- Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA
- Department of Civil, Environmental and Architectural Engineering, University of Colorado, Boulder, CO, USA
| | - John E. Barrett
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
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12
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Skelton J, Geyer KM, Lennon JT, Creed RP, Brown BL. Multi-scale ecological filters shape the crayfish microbiome. Symbiosis 2016. [DOI: 10.1007/s13199-016-0469-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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13
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Pajares S, Escalante AE, Noguez AM, García-Oliva F, Martínez-Piedragil C, Cram SS, Eguiarte LE, Souza V. Spatial heterogeneity of physicochemical properties explains differences in microbial composition in arid soils from Cuatro Cienegas, Mexico. PeerJ 2016; 4:e2459. [PMID: 27652001 PMCID: PMC5018672 DOI: 10.7717/peerj.2459] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 08/17/2016] [Indexed: 11/20/2022] Open
Abstract
Arid ecosystems are characterized by high spatial heterogeneity, and the variation among vegetation patches is a clear example. Soil biotic and abiotic factors associated with these patches have also been well documented as highly heterogeneous in space. Given the low vegetation cover and little precipitation in arid ecosystems, soil microorganisms are the main drivers of nutrient cycling. Nonetheless, little is known about the spatial distribution of microorganisms and the relationship that their diversity holds with nutrients and other physicochemical gradients in arid soils. In this study, we evaluated the spatial variability of soil microbial diversity and chemical parameters (nutrients and ion content) at local scale (meters) occurring in a gypsum-based desert soil, to gain knowledge on what soil abiotic factors control the distribution of microbes in arid ecosystems. We analyzed 32 soil samples within a 64 m2 plot and: (a) characterized microbial diversity using T-RFLPs of the bacterial 16S rRNA gene, (b) determined soil chemical parameters, and (c) identified relationships between microbial diversity and chemical properties. Overall, we found a strong correlation between microbial composition heterogeneity and spatial variation of cations (Ca2, K+) and anions (HCO\documentclass[12pt]{minimal}
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}{}${}_{4}^{2-}$\end{document}42−) content in this small plot. Our results could be attributable to spatial differences of soil saline content, favoring the patchy emergence of salt and soil microbial communities.
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Affiliation(s)
- Silvia Pajares
- Instituto de Ciencias del Mar y Limnología, Unidad Académica de Ecología y Biodiversidad Acuática, Universidad Nacional Autónoma de México, Mexico City, Mexico; Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Mexico City, Mexico
| | - Ana E Escalante
- Instituto de Ecología, Laboratorio Nacional de Ciencias de la Sostenibilidad, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Ana M Noguez
- Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Felipe García-Oliva
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México , Morelia , Michoacán , Mexico
| | - Celeste Martínez-Piedragil
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México , Morelia , Michoacán , Mexico
| | - Silke S Cram
- Instituto de Geografía, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Luis Enrique Eguiarte
- Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Valeria Souza
- Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México , Mexico City , Mexico
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14
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Buelow HN, Winter AS, Van Horn DJ, Barrett JE, Gooseff MN, Schwartz E, Takacs-Vesbach CD. Microbial Community Responses to Increased Water and Organic Matter in the Arid Soils of the McMurdo Dry Valleys, Antarctica. Front Microbiol 2016; 7:1040. [PMID: 27486436 PMCID: PMC4947590 DOI: 10.3389/fmicb.2016.01040] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 06/21/2016] [Indexed: 11/27/2022] Open
Abstract
The soils of the McMurdo Dry Valleys, Antarctica are an extreme polar desert, inhabited exclusively by microscopic taxa. This region is on the threshold of anticipated climate change, with glacial melt, permafrost thaw, and the melting of massive buried ice increasing liquid water availability and mobilizing soil nutrients. Experimental water and organic matter (OM) amendments were applied to investigate how these climate change effects may impact the soil communities. To identify active taxa and their functions, total community RNA transcripts were sequenced and annotated, and amended soils were compared with unamended control soils using differential abundance and expression analyses. Overall, taxonomic diversity declined with amendments of water and OM. The domain Bacteria increased with both amendments while Eukaryota declined from 38% of all taxa in control soils to 8 and 11% in water and OM amended soils, respectively. Among bacterial phyla, Actinobacteria (59%) dominated water-amended soils and Firmicutes (45%) dominated OM amended soils. Three bacterial phyla (Actinobacteria, Proteobacteria, and Firmicutes) were primarily responsible for the observed positive functional responses, while eukaryotic taxa experienced the majority (27 of 34) of significant transcript losses. These results indicated that as climate changes in this region, a replacement of endemic taxa adapted to dry, oligotrophic conditions by generalist, copiotrophic taxa is likely.
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Affiliation(s)
- Heather N Buelow
- Department of Biology, University of New Mexico Albuquerque, NM, USA
| | - Ara S Winter
- Department of Biology, University of New Mexico Albuquerque, NM, USA
| | - David J Van Horn
- Department of Biology, University of New Mexico Albuquerque, NM, USA
| | - John E Barrett
- Department of Biological Sciences, Virginia Tech Blacksburg, VA, USA
| | - Michael N Gooseff
- Department of Civil, Architectural, and Environmental Engineering, Institute of Arctic and Alpine Research, University of Colorado Boulder Boulder, CO, USA
| | - Egbert Schwartz
- Department of Biological Sciences, Northern Arizona University Flagstaff, AZ, USA
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15
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Tytgat B, Verleyen E, Sweetlove M, D'hondt S, Clercx P, Van Ranst E, Peeters K, Roberts S, Namsaraev Z, Wilmotte A, Vyverman W, Willems A. Bacterial community composition in relation to bedrock type and macrobiota in soils from the Sør Rondane Mountains, East Antarctica. FEMS Microbiol Ecol 2016; 92:fiw126. [PMID: 27402710 DOI: 10.1093/femsec/fiw126] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/07/2016] [Indexed: 01/06/2023] Open
Abstract
Antarctic soils are known to be oligotrophic and of having low buffering capacities. It is expected that this is particularly the case for inland high-altitude regions. We hypothesized that the bedrock type and the presence of macrobiota in these soils enforce a high selective pressure on their bacterial communities. To test this, we analyzed the bacterial community structure in 52 soil samples from the western Sør Rondane Mountains (Dronning Maud Land, East Antarctica), using the Illumina MiSeq platform in combination with ARISA fingerprinting. The samples were taken along broad environmental gradients in an area covering nearly 1000 km(2) Ordination and variation partitioning analyses revealed that the total organic carbon content was the most significant variable in structuring the bacterial communities, followed by pH, electric conductivity, bedrock type and the moisture content, while spatial distance was of relatively minor importance. Acidobacteria (Chloracidobacteria) and Actinobacteria (Actinomycetales) dominated gneiss derived mineral soil samples, while Proteobacteria (Sphingomonadaceae), Cyanobacteria, Armatimonadetes and candidate division FBP-dominated soil samples with a high total organic carbon content that were mainly situated on granite derived bedrock.
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Affiliation(s)
- Bjorn Tytgat
- Laboratory of Microbiology, Department of Microbiology and Biochemistry, Ghent University, 9000 Ghent, Belgium
| | - Elie Verleyen
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, 9000 Ghent, Belgium
| | - Maxime Sweetlove
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, 9000 Ghent, Belgium
| | - Sofie D'hondt
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, 9000 Ghent, Belgium
| | - Pia Clercx
- Laboratory of Microbiology, Department of Microbiology and Biochemistry, Ghent University, 9000 Ghent, Belgium
| | - Eric Van Ranst
- Laboratory of Soil Science, Department of Geology and Soil Science, Ghent University, 9000 Ghent, Belgium
| | - Karolien Peeters
- Laboratory of Microbiology, Department of Microbiology and Biochemistry, Ghent University, 9000 Ghent, Belgium
| | - Stephen Roberts
- British Antarctic Survey, Natural Environment Research, Cambridge, CB3 0ET, UK
| | - Zorigto Namsaraev
- Department of Biotechnology and Bioenergy, NRC 'Kurchatov Institute', Moscow, 123182, Russia Winogradsky Institute of Microbiology RAS, Moscow, 117312, Russia
| | - Annick Wilmotte
- Centre for Protein Engineering, Department of Life Sciences, Liège University, 4000 Liège, Belgium
| | - Wim Vyverman
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, 9000 Ghent, Belgium
| | - Anne Willems
- Laboratory of Microbiology, Department of Microbiology and Biochemistry, Ghent University, 9000 Ghent, Belgium
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16
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Chong CW, Pearce DA, Convey P. Emerging spatial patterns in Antarctic prokaryotes. Front Microbiol 2015; 6:1058. [PMID: 26483777 PMCID: PMC4588704 DOI: 10.3389/fmicb.2015.01058] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 09/14/2015] [Indexed: 11/13/2022] Open
Abstract
Recent advances in knowledge of patterns of biogeography in terrestrial eukaryotic organisms have led to a fundamental paradigm shift in understanding of the controls and history of life on land in Antarctica, and its interactions over the long term with the glaciological and geological processes that have shaped the continent. However, while it has long been recognized that the terrestrial ecosystems of Antarctica are dominated by microbes and their processes, knowledge of microbial diversity and distributions has lagged far behind that of the macroscopic eukaryote organisms. Increasing human contact with and activity in the continent is leading to risks of biological contamination and change in a region whose isolation has protected it for millions of years at least; these risks may be particularly acute for microbial communities which have, as yet, received scant recognition and attention. Even a matter apparently as straightforward as Protected Area designation in Antarctica requires robust biodiversity data which, in most parts of the continent, remain almost completely unavailable. A range of important contributing factors mean that it is now timely to reconsider the state of knowledge of Antarctic terrestrial prokaryotes. Rapid advances in molecular biological approaches are increasingly demonstrating that bacterial diversity in Antarctica may be far greater than previously thought, and that there is overlap in the environmental controls affecting both Antarctic prokaryotic and eukaryotic communities. Bacterial dispersal mechanisms and colonization patterns remain largely unaddressed, although evidence for regional evolutionary differentiation is rapidly accruing and, with this, there is increasing appreciation of patterns in regional bacterial biogeography in this large part of the globe. In this review, we set out to describe the state of knowledge of Antarctic prokaryote diversity patterns, drawing analogy with those of eukaryote groups where appropriate. Based on our synthesis, it is clear that spatial patterns of Antarctic prokaryotes can be unique at local scales, while the limited evidence available to date supports the group exhibiting overall regional biogeographical patterns similar to the eukaryotes. We further consider the applicability of the concept of “functional redundancy” for the Antarctic microbial community and highlight the requirements for proper consideration of their important and distinctive roles in Antarctic terrestrial ecosystems.
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Affiliation(s)
- Chun-Wie Chong
- Department of Life Sciences, School of Pharmacy, International Medical University, Kuala Lumpur Malaysia ; National Antarctic Research Center, University of Malaya, Kuala Lumpur Malaysia
| | - David A Pearce
- National Antarctic Research Center, University of Malaya, Kuala Lumpur Malaysia ; Faculty of Health and Life Sciences, University of Northumbria, Newcastle upon Tyne UK ; University Centre in Svalbard, Longyearbyen Norway ; British Antarctic Survey, Cambridge UK
| | - Peter Convey
- National Antarctic Research Center, University of Malaya, Kuala Lumpur Malaysia ; British Antarctic Survey, Cambridge UK
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17
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Gombeer S, Ramond JB, Eckardt FD, Seely M, Cowan DA. The influence of surface soil physicochemistry on the edaphic bacterial communities in contrasting terrain types of the Central Namib Desert. GEOBIOLOGY 2015; 13:494-505. [PMID: 25939371 DOI: 10.1111/gbi.12144] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 03/30/2015] [Indexed: 06/04/2023]
Abstract
Notwithstanding, the severe environmental conditions, deserts harbour a high diversity of adapted micro-organisms. In such oligotrophic environments, soil physicochemical characteristics play an important role in shaping indigenous microbial communities. This study investigates the edaphic bacterial communities of three contrasting desert terrain types (gravel plains, sand dunes and ephemeral rivers) with different surface geologies in the Central Namib Desert. For each site, we evaluated surface soil physicochemistries and used explorative T-RFLP methodology to get an indication of bacterial community diversities. While grain size was an important parameter in separating the three terrain types physicochemically and specific surface soil types could be distinguished, the desert edaphic bacterial communities displayed a high level of local spatial heterogeneity. Ten variables contributed significantly (P < 0.05) to the variance in the T-RFLP data sets: fine silt, medium and fine sand content, pH, S, Na, Zn, Al, V and Fe concentrations, and 40% of the total variance could be explained by these constraining variables. The results suggest that local physicochemical conditions play a significant role in shaping the bacterial structures in the Central Namib Desert and stress the importance of recording a wide variety of environmental descriptors to comprehensively assess the role of edaphic parameters in shaping microbial communities.
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Affiliation(s)
- S Gombeer
- Centre for Microbial Ecology and Genomics (CMEG), Genomics Research Institute, University of Pretoria, Pretoria, South Africa
| | - J-B Ramond
- Centre for Microbial Ecology and Genomics (CMEG), Genomics Research Institute, University of Pretoria, Pretoria, South Africa
| | - F D Eckardt
- Environmental and Geographical Science, Department of Geography, University of Cape Town, Cape Town, South Africa
| | - M Seely
- Gobabeb Research and Training Centre, Walvis Bay, Namibia
- School of Animal, Plant and Environmental Sciences (AP&ES), University of the Witwatersrand, Johannesburg, South Africa
| | - D A Cowan
- Centre for Microbial Ecology and Genomics (CMEG), Genomics Research Institute, University of Pretoria, Pretoria, South Africa
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18
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Kim M, Cho A, Lim HS, Hong SG, Kim JH, Lee J, Choi T, Ahn TS, Kim OS. Highly heterogeneous soil bacterial communities around Terra Nova Bay of Northern Victoria Land, Antarctica. PLoS One 2015; 10:e0119966. [PMID: 25799273 PMCID: PMC4370865 DOI: 10.1371/journal.pone.0119966] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 01/18/2015] [Indexed: 11/19/2022] Open
Abstract
Given the diminished role of biotic interactions in soils of continental Antarctica, abiotic factors are believed to play a dominant role in structuring of microbial communities. However, many ice-free regions remain unexplored, and it is unclear which environmental gradients are primarily responsible for the variations among bacterial communities. In this study, we investigated the soil bacterial community around Terra Nova Bay of Victoria Land by pyrosequencing and determined which environmental variables govern the bacterial community structure at the local scale. Six bacterial phyla, Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, Cyanobacteria, and Bacteroidetes, were dominant, but their relative abundance varied greatly across locations. Bacterial community structures were affected little by spatial distance, but structured more strongly by site, which was in accordance with the soil physicochemical compositions. At both the phylum and species levels, bacterial community structure was explained primarily by pH and water content, while certain earth elements and trace metals also played important roles in shaping community variation. The higher heterogeneity of the bacterial community structure found at this site indicates how soil bacterial communities have adapted to different compositions of edaphic variables under extreme environmental conditions. Taken together, these findings greatly advance our understanding of the adaption of soil bacterial populations to this harsh environment.
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Affiliation(s)
- Mincheol Kim
- Arctic Research Center, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Ahnna Cho
- Division of Life Sciences, Korea Polar Research Institute, Incheon, Republic of Korea
- Department of Environmental Science, Kangwon National University, Chuncheon, Republic of Korea
| | - Hyoun Soo Lim
- Department of Geological Sciences, Pusan National University, Busan, Republic of Korea
| | - Soon Gyu Hong
- Division of Life Sciences, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Ji Hee Kim
- Department of New Antarctic Station, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Joohan Lee
- Department of New Antarctic Station, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Taejin Choi
- Division of Climate Change, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Tae Seok Ahn
- Department of Environmental Science, Kangwon National University, Chuncheon, Republic of Korea
| | - Ok-Sun Kim
- Division of Life Sciences, Korea Polar Research Institute, Incheon, Republic of Korea
- * E-mail:
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19
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Schwartz E, Van Horn DJ, Buelow HN, Okie JG, Gooseff MN, Barrett JE, Takacs-Vesbach CD. Characterization of growing bacterial populations in McMurdo Dry Valley soils through stable isotope probing with (18) O-water. FEMS Microbiol Ecol 2014; 89:415-25. [PMID: 24785369 DOI: 10.1111/1574-6941.12349] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 02/21/2014] [Accepted: 04/24/2014] [Indexed: 02/01/2023] Open
Abstract
Soil microbial communities of the McMurdo Dry Valleys, Antarctica (MDV) contain representatives from at least fourteen bacterial phyla. However, given low rates of microbial activity, it is unclear whether this richness represents functioning rather than dormant members of the community. We used stable isotope probing (SIP) with (18) O-water to determine if microbial populations grow in MDV soils. Changes in the microbial community were characterized in soils amended with H2 (18) O and H2 (18) O-organic matter. Sequencing the 16S rRNA genes of the heavy and light fractions of the bacterial community DNA shows that DNA of microbial populations was labeled with (18) O-water, indicating these micro-organisms grew in the MDV soils. Significant differences existed in the community composition of the heavy and light fractions of the H2 (18) O and H2 (18) O-organic matter amended samples (Anosim P < 0.05 of weighted Unifrac distance). Control samples and the light DNA fraction of the H2 (18) O amended samples were dominated by representatives of the phyla Deinococcus-Thermus, Proteobacteria, Planctomyces, Gemmatimonadetes, Actinobacteria and Acidobacteria, whereas Proteobacteria were more prevalent in the heavy DNA fractions from the H2 (18) O-water and the H2 (18) O-water-organic matter treatments. Our results indicate that SIP with H2 (18) O can be used to distinguish active bacterial populations even in this low organic matter environment.
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Affiliation(s)
- Egbert Schwartz
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
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20
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Geyer KM, Altrichter AE, Takacs-Vesbach CD, Van Horn DJ, Gooseff MN, Barrett JE. Bacterial community composition of divergent soil habitats in a polar desert. FEMS Microbiol Ecol 2014; 89:490-4. [DOI: 10.1111/1574-6941.12306] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 02/13/2014] [Accepted: 02/13/2014] [Indexed: 01/26/2023] Open
Affiliation(s)
- Kevin M. Geyer
- Department of Biological Sciences; Virginia Polytechnic Institute and State University; Blacksburg VA USA
| | - Adam E. Altrichter
- Department of Biological Sciences; Virginia Polytechnic Institute and State University; Blacksburg VA USA
| | | | | | - Michael N. Gooseff
- Department of Civil and Environmental Engineering; Pennsylvania State University; University Park PA USA
| | - John E. Barrett
- Department of Biological Sciences; Virginia Polytechnic Institute and State University; Blacksburg VA USA
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21
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Soil microbial responses to increased moisture and organic resources along a salinity gradient in a polar desert. Appl Environ Microbiol 2014; 80:3034-43. [PMID: 24610850 DOI: 10.1128/aem.03414-13] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Microbial communities in extreme environments often have low diversity and specialized physiologies suggesting a limited resistance to change. The McMurdo Dry Valleys (MDV) are a microbially dominated, extreme ecosystem currently undergoing climate change-induced disturbances, including the melting of massive buried ice, cutting through of permafrost by streams, and warming events. These processes are increasing moisture across the landscape, altering conditions for soil communities by mobilizing nutrients and salts and stimulating autotrophic carbon inputs to soils. The goal of this study was to determine the effects of resource addition (water/organic matter) on the composition and function of microbial communities in the MDV along a natural salinity gradient representing an additional gradient of stress in an already extreme environment. Soil respiration and the activity of carbon-acquiring extracellular enzymes increased significantly (P < 0.05) with the addition of resources at the low- and moderate-salinity sites but not the high-salinity site. The bacterial community composition was altered, with an increase in Proteobacteria and Firmicutes with water and organic matter additions at the low- and moderate-salinity sites and a near dominance of Firmicutes at the high-salinity site. Principal coordinate analyses of all samples using a phylogenetically informed distance matrix (UniFrac) demonstrated discrete clustering among sites (analysis of similarity [ANOSIM], P < 0.05 and R > 0.40) and among most treatments within sites. The results from this experimental work suggest that microbial communities in this environment will undergo rapid change in response to the altered resources resulting from climate change impacts occurring in this region.
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