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Nair GR, Kooverjee BB, de Scally S, Cowan DA, Makhalanyane TP. Changes in nutrient availability substantially alter bacteria and extracellular enzymatic activities in Antarctic soils. FEMS Microbiol Ecol 2024; 100:fiae071. [PMID: 38697936 PMCID: PMC11107947 DOI: 10.1093/femsec/fiae071] [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: 09/06/2023] [Revised: 03/07/2024] [Accepted: 05/01/2024] [Indexed: 05/05/2024] Open
Abstract
In polar regions, global warming has accelerated the melting of glacial and buried ice, resulting in meltwater run-off and the mobilization of surface nutrients. Yet, the short-term effects of altered nutrient regimes on the diversity and function of soil microbiota in polyextreme environments such as Antarctica, remains poorly understood. We studied these effects by constructing soil microcosms simulating augmented carbon, nitrogen, and moisture. Addition of nitrogen significantly decreased the diversity of Antarctic soil microbial assemblages, compared with other treatments. Other treatments led to a shift in the relative abundances of these microbial assemblages although the distributional patterns were random. Only nitrogen treatment appeared to lead to distinct community structural patterns, with increases in abundance of Proteobacteria (Gammaproteobateria) and a decrease in Verrucomicrobiota (Chlamydiae and Verrucomicrobiae).The effects of extracellular enzyme activities and soil parameters on changes in microbial taxa were also significant following nitrogen addition. Structural equation modeling revealed that nutrient source and extracellular enzyme activities were positive predictors of microbial diversity. Our study highlights the effect of nitrogen addition on Antarctic soil microorganisms, supporting evidence of microbial resilience to nutrient increases. In contrast with studies suggesting that these communities may be resistant to change, Antarctic soil microbiota responded rapidly to augmented nutrient regimes.
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Affiliation(s)
- Girish R Nair
- Department of Microbiology, Faculty of Science, Stellenbosch University, Stellenbosch 7600, South Africa
- Centre for Epidemic Response and Innovation, School for Data Science and Computational Thinking, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Bhaveni B Kooverjee
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Storme de Scally
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Thulani P Makhalanyane
- Department of Microbiology, Faculty of Science, Stellenbosch University, Stellenbosch 7600, South Africa
- Centre for Epidemic Response and Innovation, School for Data Science and Computational Thinking, Stellenbosch University, Stellenbosch 7600, South Africa
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Han P, Tang X, Koch H, Dong X, Hou L, Wang D, Zhao Q, Li Z, Liu M, Lücker S, Shi G. Unveiling unique microbial nitrogen cycling and nitrification driver in coastal Antarctica. Nat Commun 2024; 15:3143. [PMID: 38609359 PMCID: PMC11014942 DOI: 10.1038/s41467-024-47392-4] [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: 11/26/2023] [Accepted: 04/01/2024] [Indexed: 04/14/2024] Open
Abstract
Largely removed from anthropogenic delivery of nitrogen (N), Antarctica has notably low levels of nitrogen. Though our understanding of biological sources of ammonia have been elucidated, the microbial drivers of nitrate (NO3-) cycling in coastal Antarctica remains poorly understood. Here, we explore microbial N cycling in coastal Antarctica, unraveling the biological origin of NO3- via oxygen isotopes in soil and lake sediment, and through the reconstruction of 1968 metagenome-assembled genomes from 29 microbial phyla. Our analysis reveals the metabolic potential for microbial N2 fixation, nitrification, and denitrification, but not for anaerobic ammonium oxidation, signifying a unique microbial N-cycling dynamic. We identify the predominance of complete ammonia oxidizing (comammox) Nitrospira, capable of performing the entire nitrification process. Their adaptive strategies to the Antarctic environment likely include synthesis of trehalose for cold stress, high substrate affinity for resource utilization, and alternate metabolic pathways for nutrient-scarce conditions. We confirm the significant role of comammox Nitrospira in the autotrophic, nitrification process via 13C-DNA-based stable isotope probing. This research highlights the crucial contribution of nitrification to the N budget in coastal Antarctica, identifying comammox Nitrospira clade B as a nitrification driver.
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Affiliation(s)
- Ping Han
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
- Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Xiufeng Tang
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Hanna Koch
- Department of Microbiology, RIBES, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands
- Center for Health & Bioresources, Bioresources Unit, AIT Austrian Institute of Technology GmbH, A-3430, Tulln, Austria
| | - Xiyang Dong
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, China
- State Key Laboratory Breeding Base of Marine Genetic Resources, Xiamen, 361005, China
- Fujian Key Laboratory of Marine Genetic Resources, Xiamen, 361005, China
| | - Lijun Hou
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
- Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Danhe Wang
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Qian Zhao
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Zhe Li
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Min Liu
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
- Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China.
| | - Sebastian Lücker
- Department of Microbiology, RIBES, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands
| | - Guitao Shi
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
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3
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Varliero G, Lebre PH, Adams B, Chown SL, Convey P, Dennis PG, Fan D, Ferrari B, Frey B, Hogg ID, Hopkins DW, Kong W, Makhalanyane T, Matcher G, Newsham KK, Stevens MI, Weigh KV, Cowan DA. Biogeographic survey of soil bacterial communities across Antarctica. MICROBIOME 2024; 12:9. [PMID: 38212738 PMCID: PMC10785390 DOI: 10.1186/s40168-023-01719-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 11/11/2023] [Indexed: 01/13/2024]
Abstract
BACKGROUND Antarctica and its unique biodiversity are increasingly at risk from the effects of global climate change and other human influences. A significant recent element underpinning strategies for Antarctic conservation has been the development of a system of Antarctic Conservation Biogeographic Regions (ACBRs). The datasets supporting this classification are, however, dominated by eukaryotic taxa, with contributions from the bacterial domain restricted to Actinomycetota and Cyanobacteriota. Nevertheless, the ice-free areas of the Antarctic continent and the sub-Antarctic islands are dominated in terms of diversity by bacteria. Our study aims to generate a comprehensive phylogenetic dataset of Antarctic bacteria with wide geographical coverage on the continent and sub-Antarctic islands, to investigate whether bacterial diversity and distribution is reflected in the current ACBRs. RESULTS Soil bacterial diversity and community composition did not fully conform with the ACBR classification. Although 19% of the variability was explained by this classification, the largest differences in bacterial community composition were between the broader continental and maritime Antarctic regions, where a degree of structural overlapping within continental and maritime bacterial communities was apparent, not fully reflecting the division into separate ACBRs. Strong divergence in soil bacterial community composition was also apparent between the Antarctic/sub-Antarctic islands and the Antarctic mainland. Bacterial communities were partially shaped by bioclimatic conditions, with 28% of dominant genera showing habitat preferences connected to at least one of the bioclimatic variables included in our analyses. These genera were also reported as indicator taxa for the ACBRs. CONCLUSIONS Overall, our data indicate that the current ACBR subdivision of the Antarctic continent does not fully reflect bacterial distribution and diversity in Antarctica. We observed considerable overlap in the structure of soil bacterial communities within the maritime Antarctic region and within the continental Antarctic region. Our results also suggest that bacterial communities might be impacted by regional climatic and other environmental changes. The dataset developed in this study provides a comprehensive baseline that will provide a valuable tool for biodiversity conservation efforts on the continent. Further studies are clearly required, and we emphasize the need for more extensive campaigns to systematically sample and characterize Antarctic and sub-Antarctic soil microbial communities. Video Abstract.
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Affiliation(s)
- Gilda Varliero
- Department of Biochemistry, Genetics and Microbiology, Centre for Microbial Ecology and Genomics, University of Pretoria, Pretoria, 0002, South Africa
- Rhizosphere Processes Group, Swiss Federal Research Institute WSL, 8903, Birmensdorf, Switzerland
| | - Pedro H Lebre
- Department of Biochemistry, Genetics and Microbiology, Centre for Microbial Ecology and Genomics, University of Pretoria, Pretoria, 0002, South Africa
| | - Byron Adams
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA
- Monte L. Bean Life Science Museum, Brigham Young University, Provo, UT, 84602, USA
| | - Steven L Chown
- Securing Antarctica's Environmental Future, School of Biological Sciences, Monash University, Clayton, VA, 3800, Australia
| | - Peter Convey
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
- Department of Zoology, University of Johannesburg, PO Box 524, Auckland Park, 2006, South Africa
- Biodiversity of Antarctic and Sub-Antarctic Ecosystems (BASE), Santiago, Chile
| | - Paul G Dennis
- School of the Environment, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Dandan Fan
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Belinda Ferrari
- School of Biotechnology and Biomolecular Sciences, University of NSW, Sydney, NSW, 2052, Australia
| | - Beat Frey
- Rhizosphere Processes Group, Swiss Federal Research Institute WSL, 8903, Birmensdorf, Switzerland
| | - Ian D Hogg
- School of Science, University of Waikato, Hamilton, New Zealand
- Canadian High Arctic Research Station, Polar Knowledge Canada, Cambridge Bay, NU, Canada
| | - David W Hopkins
- SRUC - Scotland's Rural College, West Mains Road, Edinburgh, EH9 3JG, Scotland, UK
| | - Weidong Kong
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Thulani Makhalanyane
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, 0002, South Africa
| | - Gwynneth Matcher
- Department of Biochemistry and Microbiology, Rhodes University, Makhanda, South Africa
| | - Kevin K Newsham
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Mark I Stevens
- Securing Antarctica's Environmental Future, Earth and Biological Sciences, South Australian Museum, Adelaide, SA, 5000, Australia
- School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Katherine V Weigh
- School of the Environment, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Don A Cowan
- Department of Biochemistry, Genetics and Microbiology, Centre for Microbial Ecology and Genomics, University of Pretoria, Pretoria, 0002, South Africa.
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Wan L, Liu G, Cheng H, Yang S, Shen Y, Su X. Global warming changes biomass and C:N:P stoichiometry of different components in terrestrial ecosystems. GLOBAL CHANGE BIOLOGY 2023; 29:7102-7116. [PMID: 37837281 DOI: 10.1111/gcb.16986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 09/21/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023]
Abstract
Global warming has significantly affected terrestrial ecosystems. Biomass and C:N:P stoichiometry of plants and soil is crucial for enhancing plant productivity, improving human nutrition, and regulating biogeochemical cycles. However, the effect of warming on the biomass and C:N:P stoichiometry of different components (plant, leaf, stem, root, litter, soil, and microbial biomass) in various terrestrial ecosystems remains uncertain. We conducted a comprehensive meta-analysis to investigate the global patterns of biomass and C:N:P stoichiometry responses to warming, as well as interaction relationships based on 1399 paired observations from 105 warming studies. Results indicated that warming had a significant impact on various aspects of plant growth, including an increase in plant biomass (+16.55%), plant C:N ratio (+4.15%), leaf biomass (+16.78%), stem biomass (+23.65%), root biomass (+22.00%), litter C:N ratio (+9.54%) and soil C:N ratio (+5.64%). However, it also decreased stem C:P ratio (-23.34%), root C:P ratio (-12.88%), soil N:P ratio (-14.43%) and soil C:P ratio (-16.33%). The magnitude of warming was the primary drivers of changes of biomass and C:N:P stoichiometry. By establishing the general response curves of changes in biomass and C:N:P ratios with increasing temperature, we demonstrated that warming effect on plant, root, and litter biomass shifted from negative to positive, whereas that on leaf and stem biomass changed from positive to negative as temperature increased. Additionally, the effect of warming on root C:N ratio, root biomass, and microbial biomass N:P ratios shifted from positive to negative, whereas the effects on plant N:P, leaf N:P, leaf C:P, root N:P ratios, and microbial biomass C:N ratio changed from negative to positive with increasing temperature. Our research can help assess plant productivity and optimize ecosystem stoichiometry precisely in the context of global warming.
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Affiliation(s)
- Lingfan Wan
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Guohua Liu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Hao Cheng
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Shishuai Yang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Yu Shen
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Xukun Su
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
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Zhang H, Cheng F, Sun S, Li Z. Diversity distribution and characteristics of comammox in different ecosystems. ENVIRONMENTAL RESEARCH 2022; 214:113900. [PMID: 35839911 DOI: 10.1016/j.envres.2022.113900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/14/2022] [Accepted: 07/10/2022] [Indexed: 06/15/2023]
Abstract
The discovery of complete ammonia oxidizers (comammox), which can oxidize ammonia into nitrate, has recently changed the concept of traditional nitrification. However, comparative studies on the analysis of comammox microbial community in different ecosystems are still scarce. In this study, the distribution and diversity of the comammox microbial community in farmlands, riparian zones, and river sediments in summer and winter were investigated by high-throughput sequencing. And the relative abundance of ammonia-oxidizing microorganisms was measured via their amoA genes of real-time quantitative polymerase chain reaction (qPCR). The relationships between ammonia oxidation microorganisms and the environmental factors were further analyzed. The abundance of comammox clade A was one order of magnitude lower than that of ammonia-oxidizing archaea (AOA) but higher than that of ammonia-oxidizing bacteria (AOB). The abundance of comammox was higher in summer than in winter and higher in farmland soils (1.81 ± 0.95 × 107 copies g-1) than in riparian zones and river sediments. Meanwhile, Candidatus Nitrospira nitrosa were the most widespread comammox in most samples (up to 86.31%), followed by Candidatus Nitrospira nitrificans, with a low abundance of Candidatus Nitrospira inopinata (lower than 0.61%). Furthermore, the abundance of comammox clade A had a significantly negative correlation with pH and NH4+ concentration (P < 0.05). The study revealed the potential advantages of comammox in farmlands and may be conducive to further research on comammox in microbial nitrogen cycling.
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Affiliation(s)
- Hui Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, Nanjing, 210023, China; School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Fan Cheng
- State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, Nanjing, 210023, China; School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Siyu Sun
- State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, Nanjing, 210023, China; School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Zhengkui Li
- State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, Nanjing, 210023, China; School of the Environment, Nanjing University, Nanjing, 210023, China.
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Microbiogeochemical Traits to Identify Nitrogen Hotspots in Permafrost Regions. NITROGEN 2022. [DOI: 10.3390/nitrogen3030031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Permafrost-affected tundra soils are large carbon (C) and nitrogen (N) reservoirs. However, N is largely bound in soil organic matter (SOM), and ecosystems generally have low N availability. Therefore, microbial induced N-cycling processes and N losses were considered negligible. Recent studies show that microbial N processing rates, inorganic N availability, and lateral N losses from thawing permafrost increase when vegetation cover is disturbed, resulting in reduced N uptake or increased N input from thawing permafrost. In this review, we describe currently known N hotspots, particularly bare patches in permafrost peatland or permafrost soils affected by thermokarst, and their microbiogeochemical characteristics, and present evidence for previously unrecorded N hotspots in the tundra. We summarize the current understanding of microbial N cycling processes that promote the release of the potent greenhouse gas (GHG) nitrous oxide (N2O) and the translocation of inorganic N from terrestrial into aquatic ecosystems. We suggest that certain soil characteristics and microbial traits can be used as indicators of N availability and N losses. Identifying N hotspots in permafrost soils is key to assessing the potential for N release from permafrost-affected soils under global warming, as well as the impact of increased N availability on emissions of carbon-containing GHGs.
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Abstract
Arid ecosystems cover ∼40% of the Earth's terrestrial surface and store a high proportion of the global nitrogen (N) pool. They are low-productivity, low-biomass, and polyextreme ecosystems, i.e., with (hyper)arid and (hyper)oligotrophic conditions and high surface UV irradiation and evapotranspiration. These polyextreme conditions severely limit the presence of macrofauna and -flora and, particularly, the growth and productivity of plant species. Therefore, it is generally recognized that much of the primary production (including N-input processes) and nutrient biogeochemical cycling (particularly N cycling) in these ecosystems are microbially mediated. Consequently, we present a comprehensive survey of the current state of knowledge of biotic and abiotic N-cycling processes of edaphic (i.e., open soil, biological soil crust, or plant-associated rhizosphere and rhizosheath) and hypo/endolithic refuge niches from drylands in general, including hot, cold, and polar desert ecosystems. We particularly focused on the microbially mediated biological nitrogen fixation, N mineralization, assimilatory and dissimilatory nitrate reduction, and nitrification N-input processes and the denitrification and anaerobic ammonium oxidation (anammox) N-loss processes. We note that the application of modern meta-omics and related methods has generated comprehensive data sets on the abundance, diversity, and ecology of the different N-cycling microbial guilds. However, it is worth mentioning that microbial N-cycling data from important deserts (e.g., Sahara) and quantitative rate data on N transformation processes from various desert niches are lacking or sparse. Filling this knowledge gap is particularly important, as climate change models often lack data on microbial activity and environmental microbial N-cycling communities can be key actors of climate change by producing or consuming nitrous oxide (N2O), a potent greenhouse gas.
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Ortiz M, Bosch J, Coclet C, Johnson J, Lebre P, Salawu-Rotimi A, Vikram S, Makhalanyane T, Cowan D. Microbial Nitrogen Cycling in Antarctic Soils. Microorganisms 2020; 8:E1442. [PMID: 32967081 PMCID: PMC7564152 DOI: 10.3390/microorganisms8091442] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/02/2020] [Accepted: 09/03/2020] [Indexed: 01/19/2023] Open
Abstract
The Antarctic continent is widely considered to be one of the most hostile biological habitats on Earth. Despite extreme environmental conditions, the ice-free areas of the continent, which constitute some 0.44% of the total continental land area, harbour substantial and diverse communities of macro-organisms and especially microorganisms, particularly in the more "hospitable" maritime regions. In the more extreme non-maritime regions, exemplified by the McMurdo Dry Valleys of South Victoria Land, nutrient cycling and ecosystem servicing processes in soils are largely driven by microbial communities. Nitrogen turnover is a cornerstone of ecosystem servicing. In Antarctic continental soils, specifically those lacking macrophytes, cold-active free-living diazotrophic microorganisms, particularly Cyanobacteria, are keystone taxa. The diazotrophs are complemented by heterotrophic bacterial and archaeal taxa which show the genetic capacity to perform elements of the entire N cycle, including nitrification processes such as the anammox reaction. Here, we review the current literature on nitrogen cycling genes, taxa, processes and rates from studies of Antarctic soils. In particular, we highlight the current gaps in our knowledge of the scale and contribution of these processes in south polar soils as critical data to underpin viable predictions of how such processes may alter under the impacts of future climate change.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Don Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa; (M.O.); (J.B.); (C.C.); (J.J.); (P.L.); (A.S.-R.); (S.V.); (T.M.)
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9
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Cary C, Cowan DA, McMinn A, Häggblom MM. Editorial: Thematic issue on polar and alpine microbiology. FEMS Microbiol Ecol 2020; 96:5875089. [PMID: 32697840 DOI: 10.1093/femsec/fiaa136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 11/12/2022] Open
Affiliation(s)
- Craig Cary
- International Centre for Terrestrial Antarctic Research, University of Waikato - Te Whare Wānanga o Waikato, Hamilton 3240, New Zealand
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, University of Pretoria, Hatfield 0028, Pretoria, South Africa
| | - Andrew McMinn
- Institute for Marine and Antarctic Studies, College of Science and Engineering, University of Tasmania, Battery Point, Tasmania, Australia
| | - Max M Häggblom
- Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ 08901, USA
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