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Cao F, Shu W, Liu Q, Wan J, Jiang Z, Liu M, Jiang Y. Distinct structure, assembly, and gene expression of microplankton in two Arctic estuaries with varied terrestrial inputs. ENVIRONMENTAL RESEARCH 2024; 256:119207. [PMID: 38782345 DOI: 10.1016/j.envres.2024.119207] [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: 03/08/2024] [Revised: 05/05/2024] [Accepted: 05/20/2024] [Indexed: 05/25/2024]
Abstract
The Laptev Sea is a major Marginal Sea in the Western Arctic Ocean. The Arctic amplification brought by global warming influences the hydrological properties of rivers passing through the permafrost zone, which would alter the biological community structure at continental margin. In this study, the structure, assembly, and gene expression of planktonic microbial communities in two estuaries (Protoka Ularovskaya River Estuary, PURE; Lena River Estuary, LRE) of Laptev Sea were examined to investigate the environmental effects of polar rivers. PURE and LRE exhibited distinct environmental characteristics: low temperature and high salinity for PURE, and high temperature and low salinity for LRE, influenced by runoff size. Salinity more closely influenced microbial communities in LRE, with freshwater species playing a significant role in community composition. The findings revealed differences between two estuaries in community composition and diversity. Prokaryotes and microeukaryotes had shown different assembly patterns in response to habitat changes caused by terrestrial freshwater input. Furthermore, compared with the PURE, the co-occurrence and inter-domain network of the LRE, which was more affected by terrestrial input, was more complex and stable. Functional gene prediction revealed a higher gene expression of methane metabolism in LRE than in PURE, particularly those related to methane oxidation, and this conclusion could help better explore the impact of global warming on the methane cycle in the Arctic Marginal Seas. This study explored the increased freshwater runoffs under the background of global warming dramatically affect Arctic microplankton communities from community structure, assembly and gene expression aspects.
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Affiliation(s)
- Furong Cao
- MoE Key Laboratory of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China; College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, 266003, China
| | - Wangxinze Shu
- MoE Key Laboratory of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China
| | - Qian Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, 266003, China
| | - Jiyuan Wan
- College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, 266003, China
| | - Zhiyang Jiang
- College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, 266003, China
| | - Mingjian Liu
- MoE Key Laboratory of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China; College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, 266003, China.
| | - Yong Jiang
- MoE Key Laboratory of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China; College of Marine Life Sciences, and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, 266003, China; Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao, China.
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Thomé PC, Wolinska J, Van Den Wyngaert S, Reñé A, Ilicic D, Agha R, Grossart HP, Garcés E, Monaghan MT, Strassert JFH. Phylogenomics including new sequence data of phytoplankton-infecting chytrids reveals multiple independent lifestyle transitions across the phylum. Mol Phylogenet Evol 2024; 197:108103. [PMID: 38754710 DOI: 10.1016/j.ympev.2024.108103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/01/2023] [Accepted: 05/11/2024] [Indexed: 05/18/2024]
Abstract
Parasitism is the most common lifestyle on Earth and has emerged many times independently across the eukaryotic tree of life. It is frequently found among chytrids (Chytridiomycota), which are early-branching unicellular fungi that feed osmotrophically via rhizoids as saprotrophs or parasites. Chytrids are abundant in most aquatic and terrestrial environments and fulfil important ecosystem functions. As parasites, they can have significant impacts on host populations. They cause global amphibian declines and influence the Earth's carbon cycle by terminating algal blooms. To date, the evolution of parasitism within the chytrid phylum remains unclear due to the low phylogenetic resolution of rRNA genes for the early diversification of fungi, and because few parasitic lineages have been cultured and genomic data for parasites is scarce. Here, we combine transcriptomics, culture-independent single-cell genomics and a phylogenomic approach to overcome these limitations. We newly sequenced 29 parasitic taxa and combined these with existing data to provide a robust backbone topology for the diversification of Chytridiomycota. Our analyses reveal multiple independent lifestyle transitions between parasitism and saprotrophy among chytrids and multiple host shifts by parasites. Based on these results and the parasitic lifestyle of other early-branching holomycotan lineages, we hypothesise that the chytrid last common ancestor was a parasite of phytoplankton.
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Affiliation(s)
- Pauline C Thomé
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Justyna Wolinska
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany; Institut für Biologie, Freie Universität Berlin, Berlin, Germany
| | - Silke Van Den Wyngaert
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Stechlin, Germany; Department of Biology, University of Turku, Turku, Finland
| | - Albert Reñé
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, Barcelona, Spain
| | - Doris Ilicic
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Stechlin, Germany
| | - Ramsy Agha
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Hans-Peter Grossart
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Stechlin, Germany; Institute for Biochemistry and Biology, Potsdam University, Potsdam, Germany
| | - Esther Garcés
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, Barcelona, Spain
| | - Michael T Monaghan
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany; Institut für Biologie, Freie Universität Berlin, Berlin, Germany
| | - Jürgen F H Strassert
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.
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Wang Q, Yu J, Li X, Zhang Y, Zhang J, Wang J, Mu J, Yu X, Hui R. Seasonal and anthropogenic influences on bacterioplankton communities: ecological impacts in the coastal waters of Qinhuangdao, Northern China. Front Microbiol 2024; 15:1431548. [PMID: 38962120 PMCID: PMC11220261 DOI: 10.3389/fmicb.2024.1431548] [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: 05/12/2024] [Accepted: 06/06/2024] [Indexed: 07/05/2024] Open
Abstract
Marine bacterioplankton play a crucial role in the cycling of carbon, nitrogen, and phosphorus in coastal waters. And the impact of environmental factors on bacterial community structure and ecological functions is a dynamic ongoing process. To systematically assess the relationship between environmental changes and bacterioplankton communities, this study delved into the spatiotemporal distribution and predicted metabolic characteristics of bacterioplankton communities at two estuarine beaches in Northern China. Coastal water samples were collected regularly in spring, summer, and autumn, and were analyzed in combination with environmental parameters and bacterioplankton community. Results indicated significant seasonal variations in bacterioplankton communities as Bacteroidetes and Actinobacteria were enriched in spring, Cyanobacteria proliferated in summer. While Pseudomonadota and microorganisms associated with organic matter decomposition prevailed in autumn, closely linked to seasonal variation of temperature, light and nutrients such as nitrogen and phosphorus. Particularly in summer, increased tourism activities and riverine inputs significantly raised nutrient levels, promoting the proliferation of specific photosynthetic microorganisms, potentially linked to the occurrence of phytoplankton blooms. Spearman correlation analysis further revealed significant correlations between bacterioplankton communities and environmental factors such as salinity, chlorophyll a, and total dissolved phosphorus (TDP). Additionally, the metabolic features of the spring bacterioplankton community were primarily characterized by enhanced activities in the prokaryotic carbon fixation pathways, reflecting rapid adaptation to increased light and temperature, as well as significant contributions to primary productivity. In summer, the bacterial communities were involved in enhanced glycolysis and biosynthetic pathways, reflecting high energy metabolism and responses to increased light and biomass. In autumn, microorganisms adapted to the accelerated decomposition of organic matter and the seasonal changes in environmental conditions through enhanced amino acid metabolism and material cycling pathways. These findings demonstrate that seasonal changes and human activities significantly influence the structure and function of bacterioplankton communities by altering nutrient dynamics and physical environmental conditions. This study provides important scientific insights into the marine biological responses under global change.
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Affiliation(s)
- Qiuzhen Wang
- Ocean College, Hebei Agricultural University, Qinhuangdao, China
- Hebei Key Laboratory of Nutrition Regulation and Disease Control for Aquaculture, Qinhuangdao, China
| | - Jia Yu
- Ocean College, Hebei Agricultural University, Qinhuangdao, China
| | - Xiaofang Li
- Ocean College, Hebei Agricultural University, Qinhuangdao, China
| | - Yong Zhang
- Department of Ocean Survey, Qinhuangdao Marine Center of the Ministry of Natural Resources, Qinhuangdao, China
| | - Jianle Zhang
- Department of Ocean Survey, Qinhuangdao Marine Center of the Ministry of Natural Resources, Qinhuangdao, China
| | - Jianyan Wang
- Department of Life Sciences, National Natural History Museum of China, Beijing, China
| | - Jiandong Mu
- Ecological Environment Research Department, Hebei Ocean and Fisheries Science Research Institute, Qinhuangdao, China
| | - Xinping Yu
- Ocean College, Hebei Agricultural University, Qinhuangdao, China
| | - Ruixue Hui
- Ocean College, Hebei Agricultural University, Qinhuangdao, China
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Blais MA, Vincent WF, Vigneron A, Labarre A, Matveev A, Coelho LF, Lovejoy C. Diverse winter communities and biogeochemical cycling potential in the under-ice microbial plankton of a subarctic river-to-sea continuum. Microbiol Spectr 2024; 12:e0416023. [PMID: 38511950 PMCID: PMC11210273 DOI: 10.1128/spectrum.04160-23] [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: 12/08/2023] [Accepted: 03/05/2024] [Indexed: 03/22/2024] Open
Abstract
Winter conditions greatly alter the limnological properties of lotic ecosystems and the availability of nutrients, carbon, and energy resources for microbial processes. However, the composition and metabolic capabilities of winter microbial communities are still largely uncharacterized. Here, we sampled the winter under-ice microbiome of the Great Whale River (Nunavik, Canada) and its discharge plume into Hudson Bay. We used a combination of 16S and 18S rRNA gene amplicon analysis and metagenomic sequencing to evaluate the size-fractionated composition and functional potential of the microbial plankton. These under-ice communities were diverse in taxonomic composition and metabolically versatile in terms of energy and carbon acquisition, including the capacity to carry out phototrophic processes and degrade aromatic organic matter. Limnological properties, community composition, and metabolic potential differed between shallow and deeper sites in the river, and between fresh and brackish water in the vertical profile of the plume. Community composition also varied by size fraction, with a greater richness of prokaryotes in the larger size fraction (>3 µm) and of microbial eukaryotes in the smaller size fraction (0.22-3 µm). The freshwater communities included cosmopolitan bacterial genera that were previously detected in the summer, indicating their persistence over time in a wide range of physico-chemical conditions. These observations imply that the microbial communities of subarctic rivers and their associated discharge plumes retain a broad taxonomic and functional diversity throughout the year and that microbial processing of complex terrestrial materials persists beneath the ice during the long winter season. IMPORTANCE Microbiomes vary over multiple timescales, with short- and long-term changes in the physico-chemical environment. However, there is a scarcity of data and understanding about the structure and functioning of aquatic ecosystems during winter relative to summer. This is especially the case for seasonally ice-covered rivers, limiting our understanding of these ecosystems that are common throughout the boreal, subpolar, and polar regions. Here, we examined the winter under-ice microbiome of a Canadian subarctic river and its entry to the sea to characterize the taxonomic and functional features of the microbial community. We found substantial diversity in both composition and functional capabilities, including the capacity to degrade complex terrestrial compounds, despite the constraints imposed by a prolonged seasonal ice-cover and near-freezing water temperatures. This study indicates the ecological complexity and importance of winter microbiomes in ice-covered rivers and the coastal marine environment that they discharge into.
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Affiliation(s)
- Marie-Amélie Blais
- Département de Biologie, Université Laval, Quebec City, Quebec, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
- Centre for Northern Studies (CEN), Université Laval, Quebec City, Quebec, Canada
- Takuvik Joint International Laboratory, Université Laval, Quebec City, Quebec, Canada
| | - Warwick F. Vincent
- Département de Biologie, Université Laval, Quebec City, Quebec, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
- Centre for Northern Studies (CEN), Université Laval, Quebec City, Quebec, Canada
- Takuvik Joint International Laboratory, Université Laval, Quebec City, Quebec, Canada
| | - Adrien Vigneron
- Département de Biologie, Université Laval, Quebec City, Quebec, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
- Centre for Northern Studies (CEN), Université Laval, Quebec City, Quebec, Canada
- Takuvik Joint International Laboratory, Université Laval, Quebec City, Quebec, Canada
| | - Aurélie Labarre
- Département de Biologie, Université Laval, Quebec City, Quebec, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
- Takuvik Joint International Laboratory, Université Laval, Quebec City, Quebec, Canada
- Québec-Océan, Université Laval, Quebec City, Quebec, Canada
| | - Alex Matveev
- Département de Biologie, Université Laval, Quebec City, Quebec, Canada
- Centre for Northern Studies (CEN), Université Laval, Quebec City, Quebec, Canada
- Takuvik Joint International Laboratory, Université Laval, Quebec City, Quebec, Canada
| | - Lígia Fonseca Coelho
- Centro de Química Estrutural, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
| | - Connie Lovejoy
- Département de Biologie, Université Laval, Quebec City, Quebec, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
- Takuvik Joint International Laboratory, Université Laval, Quebec City, Quebec, Canada
- Québec-Océan, Université Laval, Quebec City, Quebec, Canada
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Hörstmann C, Hattermann T, Thomé PC, Buttigieg PL, Morel I, Waite AM, John U. Biogeographic gradients of picoplankton diversity indicate increasing dominance of prokaryotes in warmer Arctic fjords. Commun Biol 2024; 7:256. [PMID: 38431695 PMCID: PMC10908816 DOI: 10.1038/s42003-024-05946-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 02/21/2024] [Indexed: 03/05/2024] Open
Abstract
Climate change is opening the Arctic Ocean to increasing human impact and ecosystem changes. Arctic fjords, the region's most productive ecosystems, are sustained by a diverse microbial community at the base of the food web. Here we show that Arctic fjords become more prokaryotic in the picoplankton (0.2-3 µm) with increasing water temperatures. Across 21 fjords, we found that Arctic fjords had proportionally more trophically diverse (autotrophic, mixotrophic, and heterotrophic) picoeukaryotes, while subarctic and temperate fjords had relatively more diverse prokaryotic trophic groups. Modeled oceanographic connectivity between fjords suggested that transport alone would create a smooth gradient in beta diversity largely following the North Atlantic Current and East Greenland Current. Deviations from this suggested that picoeukaryotes had some strong regional patterns in beta diversity that reduced the effect of oceanographic connectivity, while prokaryotes were mainly stopped in their dispersal if strong temperature differences between sites were present. Fjords located in high Arctic regions also generally had very low prokaryotic alpha diversity. Ultimately, warming of Arctic fjords could induce a fundamental shift from more trophic diverse eukaryotic- to prokaryotic-dominated communities, with profound implications for Arctic ecosystem dynamics including their productivity patterns.
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Affiliation(s)
- Cora Hörstmann
- Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany.
- Aix Marseille Univ, Universite de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France.
- Turing Center for Living Systems, Aix-Marseille University, 13009, Marseille, France.
| | - Tore Hattermann
- Norwegian Polar Institute, iC3: Centre for Ice, Cryosphere, Carbon and Climate, Framsenteret, Hjalmar Johansens gate 14, 9296, Tromsø, Norway
- Complex Systems Group, Department of Mathematics and Statistics, The Arctic University - University of Tromsø, Hansine Hansens veg 18, 9019, Tromsø, Norway
| | - Pauline C Thomé
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587, Berlin, Germany
| | - Pier Luigi Buttigieg
- Helmholtz Metadata Collaboration, GEOMAR, Wischhofstraße 1-3, 24148, Kiel, Germany
| | - Isidora Morel
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany
| | - Anya M Waite
- Ocean Frontier Institute, Dalhousie University, 1355 Oxford Street, Halifax, NS, Canada
| | - Uwe John
- Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Ammerländer Heerstraße 231, 26129, Oldenburg, Germany
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Crump BC, Bowen JL. The Microbial Ecology of Estuarine Ecosystems. ANNUAL REVIEW OF MARINE SCIENCE 2024; 16:335-360. [PMID: 37418833 DOI: 10.1146/annurev-marine-022123-101845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/09/2023]
Abstract
Human civilization relies on estuaries, and many estuarine ecosystem services are provided by microbial communities. These services include high rates of primary production that nourish harvests of commercially valuable species through fisheries and aquaculture, the transformation of terrestrial and anthropogenic materials to help ensure the water quality necessary to support recreation and tourism, and mutualisms that maintain blue carbon accumulation and storage. Research on the ecology that underlies microbial ecosystem services in estuaries has expanded greatly across a range of estuarine environments, including water, sediment, biofilms, biological reefs, and stands of seagrasses, marshes, and mangroves. Moreover, the application of new molecular tools has improved our understanding of the diversity and genomic functions of estuarine microbes. This review synthesizes recent research on microbial habitats in estuaries and the contributions of microbes to estuarine food webs, elemental cycling, and interactions with plants and animals, and highlights novel insights provided by recent advances in genomics.
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Affiliation(s)
- Byron C Crump
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, USA;
| | - Jennifer L Bowen
- Marine Science Center, Department of Marine and Environmental Sciences, Northeastern University, Nahant, Massachusetts, USA;
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Handler ER, Andersen SDJ, Gradinger R, McGovern M, Vader A, Poste AE. Seasonality in land-ocean connectivity and local processes control sediment bacterial community structure and function in a High Arctic tidal flat. FEMS Microbiol Ecol 2024; 100:fiad162. [PMID: 38111220 PMCID: PMC10799726 DOI: 10.1093/femsec/fiad162] [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: 02/27/2023] [Revised: 10/26/2023] [Accepted: 12/14/2023] [Indexed: 12/20/2023] Open
Abstract
Climate change is altering patterns of precipitation, cryosphere thaw, and land-ocean influxes, affecting understudied Arctic estuarine tidal flats. These transitional zones between terrestrial and marine systems are hotspots for biogeochemical cycling, often driven by microbial processes. We investigated surface sediment bacterial community composition and function from May to September along a river-intertidal-subtidal-fjord gradient. We paired metabarcoding of in situ communities with in vitro carbon-source utilization assays. Bacterial communities differed in space and time, alongside varying environmental conditions driven by local seasonal processes and riverine inputs, with salinity emerging as the dominant structuring factor. Terrestrial and riverine taxa were found throughout the system, likely transported with runoff. In vitro assays revealed sediment bacteria utilized a broader range of organic matter substrates when incubated in fresh and brackish water compared to marine water. These results highlight the importance of salinity for ecosystem processes in these dynamic tidal flats, with the highest potential for utilization of terrestrially derived organic matter likely limited to tidal flat areas (and times) where sediments are permeated by freshwater. Our results demonstrate that intertidal flats must be included in future studies on impacts of increased riverine discharge and transport of terrestrial organic matter on coastal carbon cycling in a warming Arctic.
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Affiliation(s)
- Eleanor R Handler
- Department of Arctic and Marine Biology, UiT – The Arctic University of Norway, Framstredet 39, 9019 Tromsø, Norway
- Department of Arctic Biology, The University Centre in Svalbard, P.O. Box 156, 9171 Longyearbyen, Norway
- Norwegian Institute for Water Research, Fram Centre for High North Research, Hjalmar Johansensgate 14, 9007 Tromsø, Norway
| | - Sebastian D J Andersen
- Department of Arctic and Marine Biology, UiT – The Arctic University of Norway, Framstredet 39, 9019 Tromsø, Norway
- Department of Arctic Biology, The University Centre in Svalbard, P.O. Box 156, 9171 Longyearbyen, Norway
- Norwegian Institute for Water Research, Fram Centre for High North Research, Hjalmar Johansensgate 14, 9007 Tromsø, Norway
| | - Rolf Gradinger
- Department of Arctic and Marine Biology, UiT – The Arctic University of Norway, Framstredet 39, 9019 Tromsø, Norway
| | - Maeve McGovern
- Department of Arctic and Marine Biology, UiT – The Arctic University of Norway, Framstredet 39, 9019 Tromsø, Norway
- Norwegian Institute for Water Research, Fram Centre for High North Research, Hjalmar Johansensgate 14, 9007 Tromsø, Norway
| | - Anna Vader
- Department of Arctic Biology, The University Centre in Svalbard, P.O. Box 156, 9171 Longyearbyen, Norway
| | - Amanda E Poste
- Department of Arctic and Marine Biology, UiT – The Arctic University of Norway, Framstredet 39, 9019 Tromsø, Norway
- Norwegian Institute for Water Research, Fram Centre for High North Research, Hjalmar Johansensgate 14, 9007 Tromsø, Norway
- Norwegian Institute for Nature Research, Fram Centre for High North Research, Hjalmar Johansensgate 14, 9007 Tromsø, Norway
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Guo P, Li C, Liu J, Chai B. Predation has a significant impact on the complexity and stability of microbial food webs in subalpine lakes. Microbiol Spectr 2023; 11:e0241123. [PMID: 37787559 PMCID: PMC10714739 DOI: 10.1128/spectrum.02411-23] [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: 06/08/2023] [Accepted: 08/18/2023] [Indexed: 10/04/2023] Open
Abstract
IMPORTANCE As an important part of microbial food webs, protists transfer organic carbon and nutrients to higher trophic levels in aquatic ecosystems. Protist predation often influences the abundance and composition of bacterial communities. However, we still do not understand whether and how predation affects the complexity and stability of microbial food webs. This study assessed the seasonal dynamic characteristics and driving factors of microbial food webs in terms of complexity and stability. Our findings have implications for future surveys to reveal the effects of climate and environmental changes.
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Affiliation(s)
- Ping Guo
- Shanxi Key Laboratory of Ecological Restoration on Loess Plateau, Institute of Loess Plateau, Shanxi University, Taiyuan, China
- Central Laboratory, Changzhi Medical College, Changzhi, China
| | - Cui Li
- Faculty of Environment Economics, Shanxi University of Finance and Economics, Taiyuan, China
| | - Jinxain Liu
- Shanxi Key Laboratory of Ecological Restoration on Loess Plateau, Institute of Loess Plateau, Shanxi University, Taiyuan, China
| | - Baofeng Chai
- Shanxi Key Laboratory of Ecological Restoration on Loess Plateau, Institute of Loess Plateau, Shanxi University, Taiyuan, China
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Robicheau BM, Tolman J, Rose S, Desai D, LaRoche J. Marine nitrogen-fixers in the Canadian Arctic Gateway are dominated by biogeographically distinct noncyanobacterial communities. FEMS Microbiol Ecol 2023; 99:fiad122. [PMID: 37951299 PMCID: PMC10656255 DOI: 10.1093/femsec/fiad122] [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: 02/28/2023] [Revised: 07/30/2023] [Accepted: 11/09/2023] [Indexed: 11/13/2023] Open
Abstract
We describe diazotrophs present during a 2015 GEOTRACES expedition through the Canadian Arctic Gateway (CAG) using nifH metabarcoding. In the less studied Labrador Sea, Bradyrhizobium sp. and Vitreoscilla sp. nifH variants were dominant, while in Baffin Bay, a Stutzerimonas stutzeri variant was dominant. In comparison, the Canadian Arctic Archipelago (CAA) was characterized by a broader set of dominant variants belonging to Desulfobulbaceae, Desulfuromonadales, Arcobacter sp., Vibrio spp., and Sulfuriferula sp. Although dominant diazotrophs fell within known nifH clusters I and III, only a few of these variants were frequently recovered in a 5-year weekly nifH times series in the coastal NW Atlantic presented herein, notably S. stutzeri and variants belonging to Desulfobacterales and Desulfuromonadales. In addition, the majority of dominant Arctic nifH variants shared low similarity (< 92% nucleotide identities) to sequences in a global noncyanobacterial diazotroph catalog recently compiled by others. We further detected UCYN-A throughout the CAG at low-levels using quantitative-PCR assays. Temperature, depth, salinity, oxygen, and nitrate were most strongly correlated to the Arctic diazotroph diversity observed, and we found a stark division between diazotroph communities of the Labrador Sea versus Baffin Bay and the CAA, hence establishing that a previously unknown biogeographic community division can occur for diazotrophs in the CAG.
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Affiliation(s)
- Brent M Robicheau
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, B3H 4R2, Canada
| | - Jennifer Tolman
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, B3H 4R2, Canada
| | - Sonja Rose
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, B3H 4R2, Canada
| | - Dhwani Desai
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, B3H 4R2, Canada
- Department of Pharmacology, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, B3H 4R2, Canada
| | - Julie LaRoche
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, B3H 4R2, Canada
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Zhang G, Jia J, Zhao Q, Wang W, Wang D, Bai J. Seasonality and assembly of soil microbial communities in coastal salt marshes invaded by a perennial grass. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 331:117247. [PMID: 36642049 DOI: 10.1016/j.jenvman.2023.117247] [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: 11/15/2022] [Revised: 12/29/2022] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
Plant invasion profoundly changes the microbial-driven processes in the ecosystem; however, the seasonality of soil microbial communities and their assembly under plant invasion is poorly understood. In this study, coastal salt marshes with native Suaeda salsa (L.) Pall. and exotic Spartina alterniflora Loisel. in the Yellow River Estuary, North China, were selected, and soil bacterial and fungal communities and their seasonal variance were characterized by metabarcoding sequencing of the 16S rRNA gene and ITS2 regions, respectively. The importance of deterministic and stochastic processes in shaping bacterial and fungal seasonal assembly was explored by the null model. Results showed that soil microbes exhibited the lowest diversities in spring, while their diversity significantly improved in summer and autumn with the increase in organic carbon and nitrogen content in soils. Strong seasonal variances in microbial communities were observed, but plant invasion reduced the seasonal variation strength of soil bacteria. For the microbial assembly, the seasonal variability of soil bacterial community was mainly controlled by homogeneous selection, whereas soil fungal community was dominantly structured by stochastic processes. Among the selected variables, soil pH was the key abiotic factor driving the seasonal changes in bacteria and fungi. The microbial function annotation derived from taxonomy-based inference suggested that carbon metabolism was relatively stronger in spring, but nitrogen and sulfur metabolism increased evidently in summer and autumn, and the proportion of saprophytic fungi increased substantially after plant invasion. The seasonal turnover of bacterial and fungal groups were tightly associated with the seasonal variation in soil carbon and nitrogen contents. Collectively, these findings reveal the strong seasonal variability of different soil microbial constituents in plant-invaded coastal salt marshes and suggest the linkage between microbial community assembly and microbial-mediated functions in the context of plant invasions.
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Affiliation(s)
- Guangliang Zhang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China; Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai, 519087, PR China
| | - Jia Jia
- Henan Key Laboratory of Ecological Environment Protection and Restoration of Yellow River Basin, Yellow River Institute of Hydraulic Research, Zhengzhou, 45003, PR China
| | - Qingqing Zhao
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Ji'nan, 250103, PR China
| | - Wei Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China
| | - Dawei Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China
| | - Junhong Bai
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China; Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta, Binzhou University, Binzhou, 256600, PR China.
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11
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Wu J, Zhu Z, Waniek JJ, Niu M, Wang Y, Zhang Z, Zhou M, Zhang R. The biogeography and co-occurrence network patterns of bacteria and microeukaryotes in the estuarine and coastal waters. MARINE ENVIRONMENTAL RESEARCH 2023; 184:105873. [PMID: 36628821 DOI: 10.1016/j.marenvres.2023.105873] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 01/02/2023] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
Community and diversity shifts of bacteria and microeukaryotes with strong environmental and spatial variations have been unveiled in the Pearl River Estuary (PRE) and northern coastal part of South China Sea (SCS). However, it is not clear what the determining factors shape the microbial community and how the biotic interactions respond to the estuarine and oceanic environment. Here, we established the multiple regression models (MRM) and co-occurrence networks on microbial communities in PRE and SCS habitats. The results showed that there were significant differences of the abiotic factors affecting the bacterial and microeukaryotic communities between PRE and SCS habitats. Salinity explained the largest variations to the microbial community dissimilarities in PRE. Whereas spatial and environmental factors determined the microbial community dissimilarities in SCS. Positive relations between parasitic lineages (e.g. Perkinsea and Cercozoa) and algal taxa (Dinophyceae, Cryptophyta, Chlorophyta and Ochrophyta) dominated in the PRE network. While parasites Syndiniales positively correlated with other Syndiniales and protists in SCS. Strong positive associations among autotrophic and heterotrophic groups were revealed in both niches. Therefore, the biotic interactions are also important and may be responsible for the unexplained variations of the abiotic factors from MRM models. Microbial network in the PRE estuarine water had weakened resistance to environmental disturbances, while the SCS network had greater capacity to maintain network stability. This study shed light on the different mechanisms of abiotic and biotic factors in shaping the compositions of bacteria and microeukaryotes between PRE and SCS niches, and highlights the weakening effect of environmental disturbances on the microbial network stability.
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Affiliation(s)
- Jinnan Wu
- School of Oceanography, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Zhu Zhu
- School of Oceanography, Shanghai Jiao Tong University, 200030, Shanghai, China.
| | - Joanna J Waniek
- Leibniz Institute for Baltic Sea Research Warnemünde, Seestrasse 15, 18119, Rostock, Germany
| | - Mingyang Niu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Yuntao Wang
- State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, 310000, Hangzhou, Zhejiang, China
| | - Zhaoru Zhang
- School of Oceanography, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Meng Zhou
- School of Oceanography, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Ruifeng Zhang
- School of Oceanography, Shanghai Jiao Tong University, 200030, Shanghai, China.
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12
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Jang SH, Na SI, Lee MJ, Yoo YD. Assessing the utility of mitochondrial gene markers in the family Suessiaceae (Dinophyta) with phylogenomic validation. Mol Phylogenet Evol 2022; 177:107625. [PMID: 36064085 DOI: 10.1016/j.ympev.2022.107625] [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: 02/02/2022] [Revised: 08/13/2022] [Accepted: 08/30/2022] [Indexed: 11/17/2022]
Abstract
The dinoflagellate family Suessiaceae comprises cosmopolitan species distributed across polar and tropical waters in both marine and freshwater ecosystems, encompassing free-living forms, symbionts, and parasites. Recently, species diversity within the family has rapidly expanded, now including a few species reported to cause red tides. Despite their ecological and evolutionary importance, classifying them within Suessiaceae is difficult due to the limitations of the existing molecular markers-the highly conserved small subunit ribosomal gene (SSU rDNA) and the presence of two indel regions of sequence fragments of the large subunit ribosomal gene (LSU rDNA)-resulting in poorly resolved phylogenetic relationships. We assessed mitochondrial cytochrome b (cob) and cytochrome c oxidase 1 (cox1) genes to develop robust molecular markers that can reveal the genetic diversity of the family Suessiaceae. The divergences of cob and cox1 sequences among the species in the family were greater than the SSU rDNA but less than the LSU rDNA and the ITS region. Moreover, the distinctive topology inferred from the mitochondrial genes provided high resolution among the suessiacean species. We examined the validity of the genetic markers using phylogenomics based on 2,023 core proteins. The divergence of the cob phylogeny was most consistent with that of the phylogenomic results. Taken together, the cob gene can be a novel marker reflecting topology at the genome-scale within the family Suessiaceae.
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Affiliation(s)
- Se Hyeon Jang
- Department of Oceanography, Chonnam National University, Gwangju 61186, South Korea.
| | - Seong In Na
- Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul 00826, South Korea
| | - Moo Joon Lee
- Department of Marine Biotechnology, Anyang University, Incheon 23038, South Korea
| | - Yeong Du Yoo
- Department of Marine Biotechnology, College of Ocean Sciences, Kunsan National University, Kunsan 54150, South Korea
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13
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Clark JB, Mannino A, Tzortziou M, Spencer RGM, Hernes P. The Transformation and Export of Organic Carbon Across an Arctic River-Delta-Ocean Continuum. JOURNAL OF GEOPHYSICAL RESEARCH. BIOGEOSCIENCES 2022; 127:e2022JG007139. [PMID: 37034423 PMCID: PMC10078588 DOI: 10.1029/2022jg007139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/22/2022] [Accepted: 11/23/2022] [Indexed: 06/19/2023]
Abstract
The Arctic Ocean is surrounded by land that feeds highly seasonal rivers with water enriched in high concentrations of dissolved and particulate organic carbon (DOC and POC). Explicit estimates of the flux of organic carbon across the land-ocean interface are difficult to quantify and many interdependent processes makes source attribution difficult. A high-resolution 3-D biogeochemical model was built for the lower Yukon River and coastal ocean to estimate biogeochemical cycling across the land-ocean continuum. The model solves for complex reactions related to organic carbon transformation, including mechanistic photodegradation and multi-reactivity microbial processing, DOC-POC flocculation, and phytoplankton dynamics. The baseline DOC and POC flux out of the delta from April to September 2019, was 977 and 536 Gg C (∼80% of the annual total), but only 50% of the DOC and 25% of the POC exited the plume across the 10 m isobath. Microbial breakdown of DOC accounted for a net loss of 168 Gg C (17% of delta export) within the plume and photodegradation accounted for a net loss of 46.6 Gg C DOC (5% of delta export) in 2019. Flocculation decreased the total organic carbon flux by only 6.4 Gg C (∼1%), while POC sinking accounted for 63.3 Gg C (10%) settling in the plume. The loss of chromophoric dissolved organic matter due to photodegradation increased the light available for phytoplankton growth throughout the coastal ocean, demonstrating the secondary effects that organic carbon reactions can have on biological processes and the net coastal carbon flux.
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Affiliation(s)
- J. Blake Clark
- Ocean Ecology LaboratoryCode 616.1NASA Goddard Space Flight CenterGreenbeltMDUSA
- Goddard Earth Sciences Technology and Research IIUniversity of Maryland, Baltimore CountyBaltimoreMDUSA
| | - Antonio Mannino
- Ocean Ecology LaboratoryCode 616.1NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Maria Tzortziou
- Department of Earth and Atmospheric SciencesThe City College of New YorkThe City University of New YorkNew YorkNYUSA
| | - Robert G. M. Spencer
- Department of Earth, Ocean and Atmospheric ScienceFlorida State UniversityTallahasseeFLUSA
| | - Peter Hernes
- Department of Land, Air and Water ResourcesUniversity of California, DavisDavisCAUSA
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14
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Jacquemot L, Vigneron A, Tremblay JÉ, Lovejoy C. Contrasting sea ice conditions shape microbial food webs in Hudson Bay (Canadian Arctic). ISME COMMUNICATIONS 2022; 2:104. [PMID: 37938285 PMCID: PMC9723562 DOI: 10.1038/s43705-022-00192-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 10/07/2022] [Accepted: 10/12/2022] [Indexed: 01/07/2023]
Abstract
The transition from ice-covered to open water is a recurring feature of the Arctic and sub-Arctic, but microbial diversity and cascading effects on the microbial food webs is poorly known. Here, we investigated microbial eukaryote, bacterial and archaeal communities in Hudson Bay (sub-Arctic, Canada) under sea-ice cover and open waters conditions. Co-occurrence networks revealed a <3 µm pico‒phytoplankton-based food web under the ice and a >3 µm nano‒microphytoplankton-based food web in the open waters. The ice-edge communities were characteristic of post-bloom conditions with high proportions of the picophytoplankton Micromonas and Bathycoccus. Nano‒ to micro‒phytoplankton and ice associated diatoms were detected throughout the water column, with the sympagic Melosira arctica exclusive to ice-covered central Hudson Bay and Thalassiosira in open northwestern Hudson Bay. Heterotrophic microbial eukaryotes and prokaryotes also differed by ice-state, suggesting a linkage between microbes at depth and surface phytoplankton bloom state. The findings suggest that a longer open water season may favor the establishment of a large phytoplankton-based food web at the subsurface chlorophyll maxima (SCM), increasing carbon export from pelagic diatoms to deeper waters and affect higher trophic levels in the deep Hudson Bay.
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Affiliation(s)
- Loïc Jacquemot
- Département de Biologie, Université Laval, Québec, QC, Canada.
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada.
| | - Adrien Vigneron
- Département de Biologie, Université Laval, Québec, QC, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | | | - Connie Lovejoy
- Département de Biologie, Université Laval, Québec, QC, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
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15
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Anderson SR, Harvey EL. Estuarine microbial networks and relationships vary between environmentally distinct communities. PeerJ 2022; 10:e14005. [PMID: 36157057 PMCID: PMC9504456 DOI: 10.7717/peerj.14005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 08/14/2022] [Indexed: 01/19/2023] Open
Abstract
Microbial interactions have profound impacts on biodiversity, biogeochemistry, and ecosystem functioning, and yet, they remain poorly understood in the ocean and with respect to changing environmental conditions. We applied hierarchical clustering of an annual 16S and 18S amplicon dataset in the Skidaway River Estuary, which revealed two similar clusters for prokaryotes (Bacteria and Archaea) and protists: Cluster 1 (March-May and November-February) and Cluster 2 (June-October). We constructed co-occurrence networks from each cluster to explore how microbial networks and relationships vary between environmentally distinct periods in the estuary. Cluster 1 communities were exposed to significantly lower temperature, sunlight, NO3, and SiO4; only NH4 was higher at this time. Several network properties (e.g., edge number, degree, and centrality) were elevated for networks constructed with Cluster 1 vs. 2 samples. There was also evidence that microbial nodes in Cluster 1 were more connected (e.g., higher edge density and lower path length) compared to Cluster 2, though opposite trends were observed when networks considered Prokaryote-Protist edges only. The number of Prokaryote-Prokaryote and Prokaryote-Protist edges increased by >100% in the Cluster 1 network, mainly involving Flavobacteriales, Rhodobacterales, Peridiniales, and Cryptomonadales associated with each other and other microbial groups (e.g., SAR11, Bacillariophyta, and Strombidiida). Several Protist-Protist associations, including Bacillariophyta correlated with Syndiniales (Dino-Groups I and II) and an Unassigned Dinophyceae group, were more prevalent in Cluster 2. Based on the type and sign of associations that increased in Cluster 1, our findings indicate that mutualistic, competitive, or predatory relationships may have been more representative among microbes when conditions were less favorable in the estuary; however, such relationships require further exploration and validation in the field and lab. Coastal networks may also be driven by shifts in the abundance of certain taxonomic or functional groups. Sustained monitoring of microbial communities over environmental gradients, both spatial and temporal, is critical to predict microbial dynamics and biogeochemistry in future marine ecosystems.
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Affiliation(s)
- Sean R. Anderson
- Northern Gulf Institute, Mississippi State University, Mississippi State, MS, United States of America,Ocean Chemistry and Ecosystems Division, Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL, United States of America
| | - Elizabeth L. Harvey
- Department of Biological Sciences, University of New Hampshire, Durham, NH, United States of America
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16
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Coelho LF, Couceiro JF, Keller-Costa T, Valente SM, Ramalho TP, Carneiro J, Comte J, Blais MA, Vincent WF, Martins Z, Canário J, Costa R. Structural shifts in sea ice prokaryotic communities across a salinity gradient in the subarctic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 827:154286. [PMID: 35247410 DOI: 10.1016/j.scitotenv.2022.154286] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 02/22/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Current knowledge of the processes that shape prokaryotic community assembly in sea ice across polar ecosystems is scarce. Here, we coupled culture-dependent (bacterial isolation on R2A medium) and culture-independent (high-throughput 16S rRNA gene sequencing) approaches to provide the first comprehensive assessment of prokaryotic communities in the late winter ice and its underlying water along a natural salinity gradient in coastal Hudson Bay, an iconic cryo-environment that marks the ecological transition between Canadian Subarctic and Arctic biomes. We found that prokaryotic community assembly processes in the ice were less selective at low salinity since typical freshwater taxa such as Frankiales, Burkholderiales, and Chitinophagales dominated both the ice and its underlying water. In contrast, there were sharp shifts in community structure between the ice and underlying water samples at sites with higher salinity, with the orders Alteromonadales and Flavobacteriales dominating the ice, while the abovementioned freshwater taxa dominated the underlying water communities. Moreover, primary producers including Cyanobium (Cyanobacteria, Synechococcales) may play a role in shaping the ice communities and were accompanied by known Planctomycetes and Verrucomicrobiae taxa. Culture-dependent analyses showed that the ice contained pigment-producing psychrotolerant or psychrophilic bacteria from the phyla Proteobacteria, Actinobacteriota, and Bacteroidota, likely favored by the combination of low temperatures and the seasonal increase in sunlight. Our findings suggest that salinity, photosynthesis and dissolved organic matter are the main drivers of prokaryotic community structure in the late winter ice of coastal Hudson Bay, the ecosystem with the fastest sea ice loss rate in the Canadian North.
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Affiliation(s)
- Lígia Fonseca Coelho
- Centro de Química Estrutural, Institute of Molecular Sciences and Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
| | - Joana Fernandes Couceiro
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Tina Keller-Costa
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Sara Martinez Valente
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Tiago Pereirinha Ramalho
- Centro de Química Estrutural, Institute of Molecular Sciences and Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Joana Carneiro
- Centro de Química Estrutural, Institute of Molecular Sciences and Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Jérôme Comte
- Centre Eau Terre Environnement, Institut National de la Recherche Scientifique, G1K 9A9 Quebec City, QC, Canada; Centre for Northern Studies (CEN), Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Marie-Amélie Blais
- Centre for Northern Studies (CEN), Université Laval, Quebec City, QC G1V 0A6, Canada; Département de biologie & Takuvik Joint International Laboratory, Université Laval, Quebec City, Québec G1V 0A6, Canada
| | - Warwick F Vincent
- Centre for Northern Studies (CEN), Université Laval, Quebec City, QC G1V 0A6, Canada; Département de biologie & Takuvik Joint International Laboratory, Université Laval, Quebec City, Québec G1V 0A6, Canada
| | - Zita Martins
- Centro de Química Estrutural, Institute of Molecular Sciences and Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - João Canário
- Centro de Química Estrutural, Institute of Molecular Sciences and Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Rodrigo Costa
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; Centro de Ciências do Mar (CCMAR), Universidade do Algarve, 8005-139 Faro, Portugal; Department of Energy - Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
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17
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Blais MA, Matveev A, Lovejoy C, Vincent WF. Size-Fractionated Microbiome Structure in Subarctic Rivers and a Coastal Plume Across DOC and Salinity Gradients. Front Microbiol 2022; 12:760282. [PMID: 35046910 PMCID: PMC8762315 DOI: 10.3389/fmicb.2021.760282] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 12/01/2021] [Indexed: 11/16/2022] Open
Abstract
Little is known about the microbial diversity of rivers that flow across the changing subarctic landscape. Using amplicon sequencing (rRNA and rRNA genes) combined with HPLC pigment analysis and physicochemical measurements, we investigated the diversity of two size fractions of planktonic Bacteria, Archaea and microbial eukaryotes along environmental gradients in the Great Whale River (GWR), Canada. This large subarctic river drains an extensive watershed that includes areas of thawing permafrost, and discharges into southeastern Hudson Bay as an extensive plume that gradually mixes with the coastal marine waters. The microbial communities differed by size-fraction (separated with a 3-μm filter), and clustered into three distinct environmental groups: (1) the GWR sites throughout a 150-km sampling transect; (2) the GWR plume in Hudson Bay; and (3) small rivers that flow through degraded permafrost landscapes. There was a downstream increase in taxonomic richness along the GWR, suggesting that sub-catchment inputs influence microbial community structure in the absence of sharp environmental gradients. Microbial community structure shifted across the salinity gradient within the plume, with changes in taxonomic composition and diversity. Rivers flowing through degraded permafrost had distinct physicochemical and microbiome characteristics, with allochthonous dissolved organic carbon explaining part of the variation in community structure. Finally, our analyses of the core microbiome indicated that while a substantial part of all communities consisted of generalists, most taxa had a more limited environmental range and may therefore be sensitive to ongoing change.
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Affiliation(s)
- Marie-Amélie Blais
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS) and Takuvik Joint International Laboratory, Université Laval, Quebec City, QC, Canada.,Centre for Northern Studies (CEN), Université Laval, Quebec City, QC, Canada
| | - Alex Matveev
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS) and Takuvik Joint International Laboratory, Université Laval, Quebec City, QC, Canada.,Centre for Northern Studies (CEN), Université Laval, Quebec City, QC, Canada
| | - Connie Lovejoy
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS) and Takuvik Joint International Laboratory, Université Laval, Quebec City, QC, Canada.,Québec-Océan, Université Laval, Quebec City, QC, Canada
| | - Warwick F Vincent
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS) and Takuvik Joint International Laboratory, Université Laval, Quebec City, QC, Canada.,Centre for Northern Studies (CEN), Université Laval, Quebec City, QC, Canada
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18
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Wang H, Chen F, Zhang C, Wang M, Kan J. Estuarine gradients dictate spatiotemporal variations of microbiome networks in the Chesapeake Bay. ENVIRONMENTAL MICROBIOME 2021; 16:22. [PMID: 34838139 PMCID: PMC8627074 DOI: 10.1186/s40793-021-00392-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 11/10/2021] [Indexed: 05/26/2023]
Abstract
BACKGROUND Annually reoccurring microbial populations with strong spatial and temporal variations have been identified in estuarine environments, especially in those with long residence time such as the Chesapeake Bay (CB). However, it is unclear how microbial taxa cooccurr and how the inter-taxa networks respond to the strong environmental gradients in the estuaries. RESULTS Here, we constructed co-occurrence networks on prokaryotic microbial communities in the CB, which included seasonal samples from seven spatial stations along the salinity gradients for three consecutive years. Our results showed that spatiotemporal variations of planktonic microbiomes promoted differentiations of the characteristics and stability of prokaryotic microbial networks in the CB estuary. Prokaryotic microbial networks exhibited a clear seasonal pattern where microbes were more closely connected during warm season compared to the associations during cold season. In addition, microbial networks were more stable in the lower Bay (ocean side) than those in the upper Bay (freshwater side). Multivariate regression tree (MRT) analysis and piecewise structural equation modeling (SEM) indicated that temperature, salinity and total suspended substances along with nutrient availability, particulate carbon and Chl a, affected the distribution and co-occurrence of microbial groups, such as Actinobacteria, Bacteroidetes, Cyanobacteria, Planctomycetes, Proteobacteria, and Verrucomicrobia. Interestingly, compared to the abundant groups (such as SAR11, Saprospiraceae and Actinomarinaceae), the rare taxa including OM60 (NOR5) clade (Gammaproteobacteria), Micrococcales (Actinobacteria), and NS11-12 marine group (Bacteroidetes) contributed greatly to the stability of microbial co-occurrence in the Bay. Modularity and cluster structures of microbial networks varied spatiotemporally, which provided valuable insights into the 'small world' (a group of more interconnected species), network stability, and habitat partitioning/preferences. CONCLUSION Our results shed light on how estuarine gradients alter the spatiotemporal variations of prokaryotic microbial networks in the estuarine ecosystem, as well as their adaptability to environmental disturbances and co-occurrence network complexity and stability.
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Affiliation(s)
- Hualong Wang
- College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, USA
| | - Feng Chen
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, USA
| | - Chuanlun Zhang
- Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, People's Republic of China
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technology, Shenzhen, People's Republic of China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Min Wang
- College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
| | - Jinjun Kan
- Microbiology Division, Stroud Water Research Center, Avondale, PA, USA.
- Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen, People's Republic of China.
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Seasonal Variability of Photosynthetic Microbial Eukaryotes (<3 µm) in the Kara Sea Revealed by 18S rDNA Metabarcoding of Sediment Trap Fluxes. PLANTS 2021; 10:plants10112394. [PMID: 34834757 PMCID: PMC8618269 DOI: 10.3390/plants10112394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 10/31/2021] [Accepted: 11/04/2021] [Indexed: 01/04/2023]
Abstract
This survey is the first to explore the seasonal cycle of microbial eukaryote diversity (<3 µm) using the NGS method and a 10-month sediment trap (2018–2019). The long-term trap was deployed from September to June in the northwestern part of the Kara Sea. A water sample collected before the sediment trap was deployed and also analyzed. The taxonomic composition of microbial eukaryotes in the water sample significantly differed from sediment trap samples, characterized by a high abundance of Ciliophora reads and low abundance of Fungi while trap samples contained an order of magnitude less Ciliophora sequences and high contribution of Fungi. Photosynthetic eukaryotes (PEs) accounting for about 34% of total protists reads were assigned to five major divisions: Chlorophyta, Cryptophyta, Dinoflagellata, Haptophyta, and Ochrophyta. The domination of phototrophic algae was revealed in late autumn. Mamiellophyceae and Trebouxiophyceae were the predominant PEs in mostly all of the studied seasons. Micromonas polaris was constantly present throughout the September–June period in the PE community. The obtained results determine the seasonal dynamics of picoplankton in order to improve our understanding of their role in polar ecosystems.
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20
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Yang N, Zhang C, Wang L, Li Y, Zhang W, Niu L, Zhang H, Wang L. Nitrogen cycling processes and the role of multi-trophic microbiota in dam-induced river-reservoir systems. WATER RESEARCH 2021; 206:117730. [PMID: 34619413 DOI: 10.1016/j.watres.2021.117730] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/25/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
The nitrogen (N) cycle is one of the most important nutrient cycles in river systems, and it plays an important role in maintaining biogeochemical balance and global climate stability. One of the main ways that humans have altered riverine ecosystems is through the construction of hydropower dams, which have major effects on biogeochemical cycles. Most previous studies examining the effects of damming on N cycling have focused on the whole budget or flux along rivers, and the role of river as N sources or sinks at the global or catchment scale. However, so far there is still lack of comprehensive and systematic summarize on N cycling and the controlling mechanisms in reservoirs affected by dam impoundment. In this review, we firstly summarize N cycling processes along the longitudinal riverine-transition-lacustrine gradient and the vertically stratified epilimnion-thermocline-hypolimnion gradient. Specifically, we highlight the direct and indirect roles of multi-trophic microbiota and their interactions in N cycling and discuss the main factors controlling these biotic processes. In addition, future research directions and challenges in incorporating multi-trophic levels in bioassessment, environmental flow design, as well as reservoir regulation and restoration are summarized. This review will aid future studies of N fluxes along dammed rivers and provide an essential reference for reservoir management to meet ecological needs.
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Affiliation(s)
- Nan Yang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing 210098, P R China
| | - Chi Zhang
- College of Mechanics and Materials, Hohai University, Xikang Road #1, Nanjing 210098, P R China
| | - Linqiong Wang
- College of Oceanography, Hohai University, Xikang Road #1, Nanjing 210098, P R China
| | - Yi Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing 210098, P R China.
| | - Wenlong Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing 210098, P R China
| | - Lihua Niu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing 210098, P R China
| | - Huanjun Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing 210098, P R China
| | - Longfei Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing 210098, P R China
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21
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Balazy K, Boehnke R, Trudnowska E, Søreide JE, Błachowiak-Samołyk K. Phenology of Oithona similis demonstrates that ecological flexibility may be a winning trait in the warming Arctic. Sci Rep 2021; 11:18599. [PMID: 34545157 PMCID: PMC8452673 DOI: 10.1038/s41598-021-98068-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 09/01/2021] [Indexed: 11/20/2022] Open
Abstract
Rapidly warming Arctic is facing significant shifts in the zooplankton size-spectra manifested as increasing numbers of the small-sized copepod Oithona similis. Here we present a unique continuous data set covering 22 months, on its copepodite structure along with environmental drivers in the Atlantic-influenced high Arctic fjord Isfjorden (Spitsbergen). Abundance maxima of O. similis were observed in September when the highest seawater temperature was recorded. A high concentration of the indicator species of Atlantification Oithona atlantica was also observed at that time. The clear dominance of O. similis in the zooplankton community during the dark, theoretically unproductive season emphasizes its substantial role in sustaining a continuous carbon flow, when most of the large herbivorous copepods fall into sleeping state. The high sex ratio observed twice in both years during periods of high primary production suggests two main reproductive events per year. O. similis reproduced even in very low temperatures (< 0 °C) previously thought to limit their fecundity, which proves its unique thermal tolerance. Our study provides a new insight on ecology of this key copepod of marine ecosystems across the globe, and thus confirm the Climatic Variability Hypothesis assuming that natural selection favour species with such flexible adaptive traits as O. similis.
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Affiliation(s)
- Kaja Balazy
- Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, Powst. Warszawy 55, 81-712, Sopot, Poland.
| | - Rafał Boehnke
- Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, Powst. Warszawy 55, 81-712, Sopot, Poland
| | - Emilia Trudnowska
- Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, Powst. Warszawy 55, 81-712, Sopot, Poland
| | - Janne E Søreide
- Department of Arctic Biology, The University Centre in Svalbard (UNIS), PB 156, 9171, Longyearbyen, Norway
| | - Katarzyna Błachowiak-Samołyk
- Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, Powst. Warszawy 55, 81-712, Sopot, Poland
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22
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Baker KD, Kellogg CTE, McClelland JW, Dunton KH, Crump BC. The Genomic Capabilities of Microbial Communities Track Seasonal Variation in Environmental Conditions of Arctic Lagoons. Front Microbiol 2021; 12:601901. [PMID: 33643234 PMCID: PMC7906997 DOI: 10.3389/fmicb.2021.601901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 01/04/2021] [Indexed: 11/30/2022] Open
Abstract
In contrast to temperate systems, Arctic lagoons that span the Alaska Beaufort Sea coast face extreme seasonality. Nine months of ice cover up to ∼1.7 m thick is followed by a spring thaw that introduces an enormous pulse of freshwater, nutrients, and organic matter into these lagoons over a relatively brief 2–3 week period. Prokaryotic communities link these subsidies to lagoon food webs through nutrient uptake, heterotrophic production, and other biogeochemical processes, but little is known about how the genomic capabilities of these communities respond to seasonal variability. Replicate water samples from two lagoons and one coastal site near Kaktovik, AK were collected in April (full ice cover), June (ice break up), and August (open water) to represent winter, spring, and summer, respectively. Samples were size fractionated to distinguish free-living and particle-attached microbial communities. Multivariate analysis of metagenomes indicated that seasonal variability in gene abundances was greater than variability between size fractions and sites, and that June differed significantly from the other months. Spring (June) gene abundances reflected the high input of watershed-sourced nutrients and organic matter via spring thaw, featuring indicator genes for denitrification possibly linked to greater organic carbon availability, and genes for processing phytoplankton-derived organic matter associated with spring blooms. Summer featured fewer indicator genes, but had increased abundances of anoxygenic photosynthesis genes, possibly associated with elevated light availability. Winter (April) gene abundances suggested low energy inputs and autotrophic bacterial metabolism, featuring indicator genes for chemoautotrophic carbon fixation, methane metabolism, and nitrification. Winter indicator genes for nitrification belonged to Thaumarchaeota and Nitrosomonadales, suggesting these organisms play an important role in oxidizing ammonium during the under-ice period. This study shows that high latitude estuarine microbial assemblages shift metabolic capabilities as they change phylogenetic composition between these extreme seasons, providing evidence that these communities may be resilient to large hydrological events in a rapidly changing Arctic.
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Affiliation(s)
- Kristina D Baker
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | | | - James W McClelland
- The University of Texas at Austin Marine Science Institute, Port Aransas, TX, United States
| | - Kenneth H Dunton
- The University of Texas at Austin Marine Science Institute, Port Aransas, TX, United States
| | - Byron C Crump
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, United States
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23
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Delpech LM, Vonnahme TR, McGovern M, Gradinger R, Præbel K, Poste AE. Terrestrial Inputs Shape Coastal Bacterial and Archaeal Communities in a High Arctic Fjord (Isfjorden, Svalbard). Front Microbiol 2021; 12:614634. [PMID: 33717004 PMCID: PMC7952621 DOI: 10.3389/fmicb.2021.614634] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 01/29/2021] [Indexed: 11/13/2022] Open
Abstract
The Arctic is experiencing dramatic changes including increases in precipitation, glacial melt, and permafrost thaw, resulting in increasing freshwater runoff to coastal waters. During the melt season, terrestrial runoff delivers carbon- and nutrient-rich freshwater to Arctic coastal waters, with unknown consequences for the microbial communities that play a key role in determining the cycling and fate of terrestrial matter at the land-ocean interface. To determine the impacts of runoff on coastal microbial (bacteria and archaea) communities, we investigated changes in pelagic microbial community structure between the early (June) and late (August) melt season in 2018 in the Isfjorden system (Svalbard). Amplicon sequences of the 16S rRNA gene were generated from water column, river and sediment samples collected in Isfjorden along fjord transects from shallow river estuaries and glacier fronts to the outer fjord. Community shifts were investigated in relation to environmental gradients, and compared to river and marine sediment microbial communities. We identified strong temporal and spatial reorganizations in the structure and composition of microbial communities during the summer months in relation to environmental conditions. Microbial diversity patterns highlighted a reorganization from rich communities in June toward more even and less rich communities in August. In June, waters enriched in dissolved organic carbon (DOC) provided a niche for copiotrophic taxa including Sulfitobacter and Octadecabacter. In August, lower DOC concentrations and Atlantic water inflow coincided with a shift toward more cosmopolitan taxa usually associated with summer stratified periods (e.g., SAR11 Clade Ia), and prevalent oligotrophic marine clades (OM60, SAR92). Higher riverine inputs of dissolved inorganic nutrients and suspended particulate matter also contributed to spatial reorganizations of communities in August. Sentinel taxa of this late summer fjord environment included taxa from the class Verrucomicrobiae (Roseibacillus, Luteolibacter), potentially indicative of a higher fraction of particle-attached bacteria. This study highlights the ecological relevance of terrestrial runoff for Arctic coastal microbial communities and how its impacts on biogeochemical conditions may make these communities susceptible to climate change.
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Affiliation(s)
- Lisa-Marie Delpech
- Department of Biology, École Normale Supérieure de Lyon, Université de Lyon, Lyon, France.,Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway.,Norwegian Institute for Water Research (NIVA), Tromsø, Norway
| | - Tobias R Vonnahme
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Maeve McGovern
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway.,Norwegian Institute for Water Research (NIVA), Tromsø, Norway
| | - Rolf Gradinger
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Kim Præbel
- Norwegian College of Fishery Science, UiT The Arctic University of Norway, Tromsø, Norway
| | - Amanda E Poste
- Norwegian Institute for Water Research (NIVA), Tromsø, Norway
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