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Antony R, Mongad D, Sanyal A, Dhotre D, Thamban M. Holed up, but thriving: Impact of multitrophic cryoconite communities on glacier elemental cycles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 933:173187. [PMID: 38750762 DOI: 10.1016/j.scitotenv.2024.173187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 05/10/2024] [Accepted: 05/10/2024] [Indexed: 05/20/2024]
Abstract
Cryoconite holes (water and sediment-filled depressions), found on glacier surfaces worldwide, serve as reservoirs of microbes, carbon, trace elements, and nutrients, transferring these components downstream via glacier hydrological networks. Through targeted amplicon sequencing of carbon and nitrogen cycling genes, coupled with functional inference-based methods, we explore the functional diversity of these mini-ecosystems within Antarctica and the Himalayas. These regions showcase distinct environmental gradients and experience varying rates of environmental change influenced by global climatic shifts. Analysis revealed a diverse array of photosynthetic microorganisms, including Stramenopiles, Cyanobacteria, Rhizobiales, Burkholderiales, and photosynthetic purple sulfur Proteobacteria. Functional inference highlighted the high potential for carbohydrate, amino acid, and lipid metabolism in the Himalayan region, where organic carbon concentrations surpassed those in Antarctica by up to 2 orders of magnitude. Nitrogen cycling processes, including fixation, nitrification, and denitrification, are evident, with Antarctic cryoconite exhibiting a pronounced capacity for nitrogen fixation, potentially compensating for the limited nitrate concentrations in this region. Processes associated with the respiration of elemental sulfur and inorganic sulfur compounds such as sulfate, sulfite, thiosulfate, and sulfide suggest the presence of a complete sulfur cycle. The Himalayan region exhibits a higher potential for sulfur cycling, likely due to the abundant sulfate ions and sulfur-bearing minerals in this region. The capability for complete iron cycling through iron oxidation and reduction reactions was also predicted. Methanogenic archaea that produce methane during organic matter decomposition and methanotrophic bacteria that utilize methane as carbon and energy sources co-exist in the cryoconite, suggesting that these niches support the complete cycling of methane. Additionally, the presence of various microfauna suggests the existence of a complex food web. Collectively, these results indicate that cryoconite holes are self-sustaining ecosystems that drive elemental cycles on glaciers and potentially control carbon, nitrogen, sulfur, and iron exports downstream.
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Affiliation(s)
- Runa Antony
- National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Vasco-da-Gama, India; GFZ German Research Centre for Geosciences, Potsdam, Germany.
| | - Dattatray Mongad
- National Centre for Microbial Resource, National Centre for Cell Science, Pune, India
| | - Aritri Sanyal
- National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Vasco-da-Gama, India
| | - Dhiraj Dhotre
- National Centre for Microbial Resource, National Centre for Cell Science, Pune, India
| | - Meloth Thamban
- National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Vasco-da-Gama, India
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Yang F, Liu Z, Zhou J, Guo X, Chen Y. Microbial Species-Area Relationships on the Skins of Amphibian Hosts. Microbiol Spectr 2023; 11:e0177122. [PMID: 36995232 PMCID: PMC10269671 DOI: 10.1128/spectrum.01771-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 02/28/2023] [Indexed: 03/31/2023] Open
Abstract
Unlike species-area relationships (SARs) that have been widely reported for plants and animals on Earth, there is no clear understanding of the SARs for microorganisms. In this study, 358 specimens of 10 amphibian host species collected from the rural Chengdu region of southwest China were selected as island models for evaluating SAR curve shapes and assessing the skin microbiota from different amphibian species. The results showed that skin microbial diversity, measured using Hill's number, presented significant differences between hosts, but the difference was insignificant between habitat-specific classifications of hosts. As for microbial SARs, other than the classical power-law (PL) model describing an expected steady increase in microbial diversity as sampled skin area increases, two additional trends were observed: (i) microbial diversity first rises and gradually decreases after reaching a maximum accrual diversity (MaxAD) and (ii) microbial diversity decreases and starts to rise after reaching the minimum accrual diversity (MinAD). Among the four SAR statistical models compared, it was consistently found that the models that can describe MaxAD were favorably selected in the highest frequency. Models that can describe MinAD and PL model also performed reasonably well. However, PL had the poorest fitting power, implying the necessity of introducing biologically meaningful complex SAR models in microbial diversity research. In conclusion, through multihost analyses, our study provided compelling evidence that microbial SARs are complex and nonlinear. A variety of ecological mechanisms may be used for explaining these, including, but not limited to, community saturation, small-island effects, or sampling heterogeneity. IMPORTANCE In this study, we investigate species-area relationships (SARs) for skin-borne symbiotic microbes of wildlife hosts. Unlike the traditional SARs for plants and animals, symbiotic microbial SARs were complex. We found that both U-shaped and inverted U-shaped SAR models were widely favored for microbial taxa than the well-known power-law model in different host species. These favored models presented interesting statistical features, including minimal or maximal accrual diversity or inflection point. We provide intuitive derivations of these statistical properties. We showed that different habitat-specific amphibian hosts did not present distinct microbial diversity and skin-related SAR patterns. We predicted that approximately 600 to 1,400 cm2 (in two-dimensional [2D] measurement) or approximately 1,200 to 3 500 cm2 (in 3D measurement) are the skin area threshold range that can allow the emergence of minimal or maximal accrual microbial diversity with high chances. Finally, we list a variety of ecological mechanisms that may be used for explaining the observed nonlinear SAR trends.
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Affiliation(s)
- Fan Yang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, People’s Republic of China
- University of Chinese Academy of Science, Beijing, People’s Republic of China
| | - Zhidong Liu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, People’s Republic of China
- University of Chinese Academy of Science, Beijing, People’s Republic of China
| | - Jin Zhou
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, People’s Republic of China
- University of Chinese Academy of Science, Beijing, People’s Republic of China
| | - Xuecheng Guo
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, People’s Republic of China
- University of Chinese Academy of Science, Beijing, People’s Republic of China
| | - Youhua Chen
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, People’s Republic of China
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Pittino F, Ambrosini R, Seeger M, Azzoni RS, Diolaiuti G, Alviz Gazitua P, Franzetti A. Geographical variability of bacterial communities of cryoconite holes of Andean glaciers. Sci Rep 2023; 13:2633. [PMID: 36788266 PMCID: PMC9929092 DOI: 10.1038/s41598-022-24373-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 11/14/2022] [Indexed: 02/16/2023] Open
Abstract
Cryoconite holes, ponds full of melting water with sediment on the bottom, are hotspots of biodiversity on glacier surfaces and host dynamic micro-ecosystems. They have been extensively investigated in different areas of the world (e.g., the Arctic, Antarctic, Alps, and Himalaya), but so far no study has described the bacterial communities of the glaciers in the Andes, the world's longest mountain range. In this study, we describe the bacterial communities of three small (< 2 km2) high-elevation (< 4200 m a.s.l.) glaciers of the Central Andes (Iver, East Iver and Morado glaciers) and two large (> 85 km2) glaciers of the Patagonian Andes (Exploradores and Perito Moreno glaciers) whose ablation tongues reach low altitude (< 300 m a.s.l.). Results show that the bacterial communities were generally similar to those observed in the cryoconite holes of other continents, but with few cyanobacteria (0.5% of sequences). The most abundant orders were Betaproteobacteriales, Cytophagales, Chitinophagales, Acetobacterales, Frankiales, Armatimonadales, Sphingobacteriales, Rhizobiales, Bacteroidales, Sphingomonadales, and Micrococcales. The bacterial communities differed between glaciers and both water pH and O2 concentration appeared to influence the bacterial community composition. This work thus provides the first description of the bacterial communities in cryoconite holes of South American glaciers.
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Affiliation(s)
- F. Pittino
- grid.7563.70000 0001 2174 1754Department of Earth and Environmental Sciences (DISAT), Università degli Studi di Milano-Bicocca, Milan, Italy ,grid.419754.a0000 0001 2259 5533WSL Swiss Federal Research Institute, Birmensdorf, Switzerland
| | - R. Ambrosini
- grid.4708.b0000 0004 1757 2822Laboratory of Glacier Ecology, Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - M. Seeger
- grid.12148.3e0000 0001 1958 645XMolecular Microbiology and Environmental Biotechnology Laboratory, Department of Chemistry, Universidad Técnica Federico Santa María, Valparaiso, Chile
| | - R. S. Azzoni
- grid.4708.b0000 0004 1757 2822Laboratory of Glacier Ecology, Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy ,grid.4708.b0000 0004 1757 2822Department of Earth Science “Ardito Desio”, Università degli Studi di Milano, Milan, Italy
| | - G. Diolaiuti
- grid.4708.b0000 0004 1757 2822Laboratory of Glacier Ecology, Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - P. Alviz Gazitua
- grid.442234.70000 0001 2295 9069Departamento de Ciencias Biológicas, Universidad de los Lagos, Osorno, Chile
| | - A. Franzetti
- grid.7563.70000 0001 2174 1754Department of Earth and Environmental Sciences (DISAT), Università degli Studi di Milano-Bicocca, Milan, Italy
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Deng W, Yuan CL, Li N, Liu SR, Yang XY, Xiao W. Island Formation History Determines Microbial Species-Area Relationships. MICROBIAL ECOLOGY 2022; 84:1055-1061. [PMID: 34750668 DOI: 10.1007/s00248-021-01906-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/20/2021] [Indexed: 06/13/2023]
Abstract
The species-area relationship (SAR) and its mechanisms regarding microbes are not as clear as those of plants and animals; this may result from the impact of sampling effects and the confusion between SAR and distance attenuation. We hypothesize that we can find more accurate microbial SAR curve, after removing these two factors. In this study, 27 leaves of three horticultural plants were selected as island models, and microbial biodiversity assessment was done with HTS (high-throughput sequencing). The separate and small systems using leaves as islands allow us to conduct a comprehensive survey of the microbial biodiversity of the leaves, without disturbance from sampling effects and distance attenuation effects. Interestingly, we did not find microbial SAR in those 27 leaves (also not found in evergreen trees Magnolia grandiflora and Eriobotrya japonica), but we did find significant microbial SAR in deciduous tree Ficus altissima. No significant differences were found between the different trees at the alpha diversity level of microbial biodiversity, but quite different on beta diversity. The results of beta diversity partition showed that F. altissima had the highest similarity of the microbial community among the leaves compared to those of M. grandiflora and E. japonica. Since leaf genesis in deciduous plants is more simultaneous than in evergreen plants; the result suggested that inconsistent historical background of leaf islands may mask microbial SAR. Thus, intensive sampling and consistent historical background are important for understanding microbial SAR.
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Affiliation(s)
- Wei Deng
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, China
| | - Cai-Lian Yuan
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, China
| | - Na Li
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, China
| | - Shuo-Ran Liu
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, China
| | - Xiao-Yan Yang
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, China.
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, China.
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, China.
| | - Wen Xiao
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, China.
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, China.
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, China.
- International Centre of Biodiversity and Primates Conservation, Dali, 671003, Yunnan, China.
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Deng W, Liu LL, Yu GB, Li N, Yang XY, Xiao W. Testing the Resource Hypothesis of Species-Area Relationships: Extinction Cannot Work Alone. Microorganisms 2022; 10:1993. [PMID: 36296268 PMCID: PMC9611600 DOI: 10.3390/microorganisms10101993] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/04/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022] Open
Abstract
The mechanisms that underpin the species-area relationship (SAR) are crucial for both the development of biogeographic theory and the application of biodiversity conservation. Since its origin, the resource hypothesis, which proposes that rich resources in vast ecosystems will lower extinction rates and shape the SAR, has not been tested. The impossibility to quantify resources and extinction rates using plants and animals as research subjects, as well as the inability to rule out the influences of the area per se, habitat diversity, dispersal, and the historical background of biodiversity, make testing this hypothesis problematic. To address these challenges and test this hypothesis, two sets of microbial microcosm experimental systems with positive and negative correlated resources and volumes were created in this work. The results of 157 high-throughput sequencing monitoring sessions at 11 time points over 30 consecutive days showed that neither of the experimental groups with positive or negative correlations between total resources and microcosm volume had a significant SAR, and there were no negative correlations between extinction rates and resources. Therefore, in our microcosmic system, resources do not influence extinction rates or shape the SAR. Dispersal should be the principal mode of action if the resource theory is correct.
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Affiliation(s)
- Wei Deng
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671003, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali 671003, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali 671003, China
| | - Li-Lei Liu
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671003, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali 671003, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali 671003, China
| | - Guo-Bin Yu
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671003, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali 671003, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali 671003, China
| | - Na Li
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671003, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali 671003, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali 671003, China
- International Centre of Biodiversity and Primates Conservation, Dali 671003, China
| | - Xiao-Yan Yang
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671003, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali 671003, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali 671003, China
| | - Wen Xiao
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671003, China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali 671003, China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali 671003, China
- International Centre of Biodiversity and Primates Conservation, Dali 671003, China
- Yunling Black-and-White Snub-Nosed Monkey Observation and Research Station of Yunnan Province, Dali 761003, China
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Gattoni K, Gendron EMS, Borgmeier A, McQueen JP, Mullin PG, Powers K, Powers TO, Porazinska DL. Context-dependent role of abiotic and biotic factors structuring nematode communities along two environmental gradients. Mol Ecol 2022; 31:3903-3916. [PMID: 35593510 DOI: 10.1111/mec.16541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 04/14/2022] [Accepted: 05/17/2022] [Indexed: 11/28/2022]
Abstract
Although abiotic environmental factors have been historically regarded as the dominant deterministic process in microbial community assembly, recent studies indicate that biotic interactions may be equally significant. However, the extent to which both processes are important in assembly of belowground communities is unknown. Along two environmental gradients: alkalinity (ranging from pH ~7 to ~11) and habitat type (lakes, shorelines, and prairies around lakes) present in the Western Nebraska Sandhills, we used 18S rRNA gene marker metabarcoding and statistical analyses, including generalized dissimilarity modelling (GDM), to evaluate the dynamics between abiotic and biotic factors that might play a role in nematode community assembly. Lakes supported the least diverse and prairies the most diverse communities with completely distinct compositions. We also observed a potential role of alkalinity in shaping these communities but only in lakes. Generally, GDMs indicated the influence of both abiotic and biotic factors. However, their relative importance in explaining community variability was dependent on the habitat. Biotic factors influenced the lake communities most, followed by shorelines and prairies, explaining ~47%, 27% and 8% of the variation, respectively. In contrast, the role of abiotic factors was relatively similar in lakes, shorelines and prairies (~15%, 18% and 14% of the variation, respectively). Most variation in the shorelines (62%) and prairies (82%) remained unexplained, suggesting the potential importance of factors associated with specific traits or a stronger role of stochastic processes. Nevertheless, our findings suggest both deterministic processes are important in nematode community assembly, but their specific contributions are context-dependent.
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Affiliation(s)
- Kaitlin Gattoni
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | | | - Abigail Borgmeier
- Department of Plant Pathology, 406 Plant Science, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - J Parr McQueen
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | - Peter G Mullin
- Department of Plant Pathology, 406 Plant Science, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Kris Powers
- Department of Plant Pathology, 406 Plant Science, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Thomas O Powers
- Department of Plant Pathology, 406 Plant Science, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Dorota L Porazinska
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
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Solon AJ, Mastrangelo C, Vimercati L, Sommers P, Darcy JL, Gendron EMS, Porazinska DL, Schmidt SK. Gullies and Moraines Are Islands of Biodiversity in an Arid, Mountain Landscape, Asgard Range, Antarctica. Front Microbiol 2021; 12:654135. [PMID: 34177836 PMCID: PMC8222675 DOI: 10.3389/fmicb.2021.654135] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 05/04/2021] [Indexed: 12/30/2022] Open
Abstract
Cold, dry, and nutrient-poor, the McMurdo Dry Valleys of Antarctica are among the most extreme terrestrial environments on Earth. Numerous studies have described microbial communities of low elevation soils and streams below glaciers, while less is known about microbial communities in higher elevation soils above glaciers. We characterized microbial life in four landscape features (habitats) of a mountain in Taylor Valley. These habitats varied significantly in soil moisture and include moist soils of a (1) lateral glacial moraine, (2) gully that terminates at the moraine, and very dry soils on (3) a southeastern slope and (4) dry sites near the gully. Using rRNA gene PCR amplicon sequencing of Bacteria and Archaea (16S SSU) and eukaryotes (18S SSU), we found that all habitat types harbored significantly different bacterial and eukaryotic communities and that these differences were most apparent when comparing habitats that had macroscopically visible soil crusts (gully and moraine) to habitats with no visible crusts (near gully and slope). These differences were driven by a relative predominance of Actinobacteria and a Colpodella sp. in non-crust habitats, and by phototrophic bacteria and eukaryotes (e.g., a moss) and predators (e.g., tardigrades) in habitats with biological soil crusts (gully and moraine). The gully and moraine also had significantly higher 16S and 18S ESV richness than the other two habitat types. We further found that many of the phototrophic bacteria and eukaryotes of the gully and moraine share high sequence identity with phototrophs from moist and wet areas elsewhere in the Dry Valleys and other cold desert ecosystems. These include a Moss (Bryum sp.), several algae (e.g., a Chlorococcum sp.) and cyanobacteria (e.g., Nostoc and Phormidium spp.). Overall, the results reported here broaden the diversity of habitat types that have been studied in the Dry Valleys of Antarctica and suggest future avenues of research to more definitively understand the biogeography and factors controlling microbial diversity in this unique ecosystem.
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Affiliation(s)
- Adam J Solon
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO, United States
| | - Claire Mastrangelo
- School of Public Health, University of California, Berkeley, Berkeley, CA, United States
| | - Lara Vimercati
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO, United States
| | - Pacifica Sommers
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO, United States
| | - John L Darcy
- Division of Biomedical Informatics and Personalized Medicine, University of Colorado-Anschutz Medical Campus, Denver, CO, United States
| | - Eli M S Gendron
- Department of Entomology and Nematology, University of Florida, Gainesville, FL, United States
| | - Dorota L Porazinska
- Department of Entomology and Nematology, University of Florida, Gainesville, FL, United States
| | - S K Schmidt
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO, United States
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16S rRNA gene and 18S rRNA gene diversity in microbial mat communities in meltwater ponds on the McMurdo Ice Shelf, Antarctica. Polar Biol 2021. [DOI: 10.1007/s00300-021-02843-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
AbstractThe undulating ice of the McMurdo Ice Shelf, Southern Victoria Land, supports one of the largest networks of ice-based, multiyear meltwater pond habitats in Antarctica, where microbial mats are abundant and contribute most of the biomass and biodiversity. We used 16S rRNA and 18S rRNA gene high-throughput sequencing to compare variance of the community structure in microbial mats within and between ponds with different salinities and pH. Proteobacteria and Cyanobacteria were the most abundant phyla, and composition at OTU level was highly specific for the meltwater ponds with strong community sorting along the salinity gradient. Our study provides the first detailed evaluation of eukaryote communities for the McMurdo Ice Shelf using the 18S rRNA gene. They were dominated by Ochrophyta, Chlorophyta and Ciliophora, consistent with previous microscopic analyses, but many OTUs belonging to less well-described heterotrophic protists from Antarctic ice shelves were also identified including Amoebozoa, Rhizaria and Labyrinthulea. Comparison of 16S and 18S rRNA gene communities showed that the Eukaryotes had lower richness and greater similarity between ponds in comparison with Bacteria and Archaea communities on the McMurdo Ice shelf. While there was a weak correlation between community dissimilarity and geographic distance, the congruity of microbial assemblages within ponds, especially for Bacteria and Archaea, implies strong habitat filtering in ice shelf meltwater pond ecosystems, especially due to salinity. These findings help to understand processes that are important in sustaining biodiversity and the impact of climate change on ice-based aquatic habitats in Antarctica.
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