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Kunz CF, Goldbecker ES, Darienko T, de Vries J. Genome evolution: Zygnematophyceae on ice. THE NEW PHYTOLOGIST 2024; 244:1125-1127. [PMID: 39001590 DOI: 10.1111/nph.19960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2024]
Abstract
This article is a Commentary on Bowles et al. (2024), 244: 1629–1643.
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Affiliation(s)
- Cäcilia F Kunz
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Goettingen, Goldschmidtstr. 1, 37077, Göttingen, Germany
| | - Elisa S Goldbecker
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Goettingen, Goldschmidtstr. 1, 37077, Göttingen, Germany
| | - Tatyana Darienko
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Goettingen, Goldschmidtstr. 1, 37077, Göttingen, Germany
| | - Jan de Vries
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Goettingen, Goldschmidtstr. 1, 37077, Göttingen, Germany
- Department of Applied Bioinformatics, Campus Institute Data Science (CIDAS), University of Goettingen, Goldschmidtstr. 1, 37077, Goettingen, Germany
- Department of Applied Bioinformatics, Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goldschmidtstr. 1, 37077, Goettingen, Germany
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Bowles AMC, Williams TA, Donoghue PCJ, Campbell DA, Williamson CJ. Metagenome-assembled genome of the glacier alga Ancylonema yields insights into the evolution of streptophyte life on ice and land. THE NEW PHYTOLOGIST 2024; 244:1629-1643. [PMID: 38840553 DOI: 10.1111/nph.19860] [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: 03/06/2024] [Accepted: 05/03/2024] [Indexed: 06/07/2024]
Abstract
Contemporary glaciers are inhabited by streptophyte algae that balance photosynthesis and growth with tolerance of low temperature, desiccation and UV radiation. These same environmental challenges have been hypothesised as the driving force behind the evolution of land plants from streptophyte algal ancestors in the Cryogenian (720-635 million years ago). We sequenced, assembled and analysed the metagenome-assembled genome of the glacier alga Ancylonema nordenskiöldii to investigate its adaptations to life in ice, and whether this represents a vestige of Cryogenian exaptations. Phylogenetic analysis confirms the placement of glacier algae within the sister lineage to land plants, Zygnematophyceae. The metagenome-assembled genome is characterised by an expansion of genes involved in tolerance of high irradiance and UV light, while lineage-specific diversification is linked to the novel screening pigmentation of glacier algae. We found no support for the hypothesis of a common genomic basis for adaptations to ice and to land in streptophytes. Comparative genomics revealed that the reductive morphological evolution in the ancestor of Zygnematophyceae was accompanied by reductive genome evolution. This first genome-scale data for glacier algae suggests an Ancylonema-specific adaptation to the cryosphere, and sheds light on the genome evolution of land plants and Zygnematophyceae.
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Affiliation(s)
- Alexander M C Bowles
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ, UK
| | - Tom A Williams
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ, UK
| | - Philip C J Donoghue
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ, UK
| | - Douglas A Campbell
- Department of Biology, Mount Allison University, Sackville, NB, E4L 1H3, Canada
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Peter EK, Jaeger C, Lisec J, Peters RS, Mourot R, Rossel PE, Tranter M, Anesio AM, Benning LG. Endometabolic profiling of pigmented glacier ice algae: the impact of sample processing. Metabolomics 2024; 20:98. [PMID: 39123092 PMCID: PMC11315761 DOI: 10.1007/s11306-024-02147-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 06/24/2024] [Indexed: 08/12/2024]
Abstract
INTRODUCTION Glacier ice algae, mainly Ancylonema alaskanum and Ancylonema nordenskiöldi, bloom on Greenland Ice Sheet bare ice surfaces. They significantly decrease surface albedo due to their purple-brown pigmentation, thus increasing melt. Little is known about their metabolic adaptation and factors controlling algal growth dynamics and pigment formation. A challenge in obtaining such data is the necessity of melting samples, which delays preservation and introduces bias to metabolomic analysis. There is a need to evaluate the physiological response of algae to melting and establish consistent sample processing strategies for metabolomics of ice microbial communities. OBJECTIVES To address the impact of sample melting procedure on metabolic characterization and establish a processing and analytical workflow for endometabolic profiling of glacier ice algae. METHODS We employed untargeted, high-resolution mass spectrometry and tested the effect of sample melt temperature (10, 15, 20 °C) and processing delay (up to 49 h) on the metabolome and lipidome, and complemented this approach with cell counts (FlowCam), photophysiological analysis (PAM) and diversity characterization. RESULTS AND CONCLUSION We putatively identified 804 metabolites, with glycerolipids, glycerophospholipids and fatty acyls being the most prominent superclasses (> 50% of identified metabolites). Among the polar metabolome, carbohydrates and amino acid-derivatives were the most abundant. We show that 8% of the metabolome is affected by melt duration, with a pronounced decrease in betaine membrane lipids and pigment precursors, and an increase in phospholipids. Controlled fast melting at 10 °C resulted in the highest consistency, and is our recommendation for future supraglacial metabolomics studies.
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Affiliation(s)
- Elisa K Peter
- German Research Centre for Geosciences - GFZ, 14473, Potsdam, Germany.
- Department of Earth Sciences, Freie Universität Berlin, 12249, Berlin, Germany.
| | - Carsten Jaeger
- Bundesanstalt für Materialforschung und -prüfung (BAM), 12489, Berlin, Germany
| | - Jan Lisec
- Bundesanstalt für Materialforschung und -prüfung (BAM), 12489, Berlin, Germany
| | - R Sven Peters
- German Research Centre for Geosciences - GFZ, 14473, Potsdam, Germany
| | - Rey Mourot
- German Research Centre for Geosciences - GFZ, 14473, Potsdam, Germany
- Department of Earth Sciences, Freie Universität Berlin, 12249, Berlin, Germany
| | - Pamela E Rossel
- German Research Centre for Geosciences - GFZ, 14473, Potsdam, Germany
| | - Martyn Tranter
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark
| | - Alexandre M Anesio
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark
| | - Liane G Benning
- German Research Centre for Geosciences - GFZ, 14473, Potsdam, Germany.
- Department of Earth Sciences, Freie Universität Berlin, 12249, Berlin, Germany.
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Perini L, Sipes K, Zervas A, Bellas C, Lutz S, Moniruzzaman M, Mourot R, Benning LG, Tranter M, Anesio AM. Giant viral signatures on the Greenland ice sheet. MICROBIOME 2024; 12:91. [PMID: 38760842 PMCID: PMC11100222 DOI: 10.1186/s40168-024-01796-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/18/2024] [Indexed: 05/19/2024]
Abstract
BACKGROUND Dark pigmented snow and glacier ice algae on glaciers and ice sheets contribute to accelerating melt. The biological controls on these algae, particularly the role of viruses, remain poorly understood. Giant viruses, classified under the nucleocytoplasmic large DNA viruses (NCLDV) supergroup (phylum Nucleocytoviricota), are diverse and globally distributed. NCLDVs are known to infect eukaryotic cells in marine and freshwater environments, providing a biological control on the algal population in these ecosystems. However, there is very limited information on the diversity and ecosystem function of NCLDVs in terrestrial icy habitats. RESULTS In this study, we investigate for the first time giant viruses and their host connections on ice and snow habitats, such as cryoconite, dark ice, ice core, red and green snow, and genomic assemblies of five cultivated Chlorophyta snow algae. Giant virus marker genes were present in almost all samples; the highest abundances were recovered from red snow and the snow algae genomic assemblies, followed by green snow and dark ice. The variety of active algae and protists in these GrIS habitats containing NCLDV marker genes suggests that infection can occur on a range of eukaryotic hosts. Metagenomic data from red and green snow contained evidence of giant virus metagenome-assembled genomes from the orders Imitervirales, Asfuvirales, and Algavirales. CONCLUSION Our study highlights NCLDV family signatures in snow and ice samples from the Greenland ice sheet. Giant virus metagenome-assembled genomes (GVMAGs) were found in red snow samples, and related NCLDV marker genes were identified for the first time in snow algal culture genomic assemblies; implying a relationship between the NCLDVs and snow algae. Metatranscriptomic viral genes also aligned with metagenomic sequences, suggesting that NCLDVs are an active component of the microbial community and are potential "top-down" controls of the eukaryotic algal and protistan members. This study reveals the unprecedented presence of a diverse community of NCLDVs in a variety of glacial habitats dominated by algae.
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Affiliation(s)
- Laura Perini
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark.
| | - Katie Sipes
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
| | - Athanasios Zervas
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
| | | | - Stefanie Lutz
- Department of Agroecology and Environment, Plant-Soil Interactions, Agroscope, Zurich, Switzerland
- German Research Centre for Geosciences, Helmholtz Centre Potsdam, Telegrafenberg, Potsdam, 14473, Germany
| | - Mohammad Moniruzzaman
- Department of Biological Sciences, Rosenstiel School of Marine, Atmospheric and Earth Science, University of Miami, Coral Gables, FL, USA
| | - Rey Mourot
- German Research Centre for Geosciences, Helmholtz Centre Potsdam, Telegrafenberg, Potsdam, 14473, Germany
- Department of Earth Sciences, Freie Universität Berlin, Berlin, 12249, Germany
| | - Liane G Benning
- German Research Centre for Geosciences, Helmholtz Centre Potsdam, Telegrafenberg, Potsdam, 14473, Germany
- Department of Earth Sciences, Freie Universität Berlin, Berlin, 12249, Germany
| | - Martyn Tranter
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
| | - Alexandre M Anesio
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
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Millar JL, Broadwell ELM, Lewis M, Bowles AMC, Tedstone AJ, Williamson CJ. Alpine glacier algal bloom during a record melt year. Front Microbiol 2024; 15:1356376. [PMID: 38444808 PMCID: PMC10912336 DOI: 10.3389/fmicb.2024.1356376] [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: 12/15/2023] [Accepted: 01/08/2024] [Indexed: 03/07/2024] Open
Abstract
Glacier algal blooms dominate the surfaces of glaciers and ice sheets during summer melt seasons, with larger blooms anticipated in years that experience the greatest melt. Here, we characterize the glacier algal bloom proliferating on Morteratsch glacier, Switzerland, during the record 2022 melt season, when the Swiss Alps lost three times more ice than the decadal average. Glacier algal cellular abundance (cells ml-1), biovolume (μm3 cell-1), photophysiology (Fv/Fm, rETRmax), and stoichiometry (C:N ratios) were constrained across three elevations on Morteratsch glacier during late August 2022 and compared with measurements of aqueous geochemistry and outputs of nutrient spiking experiments. While a substantial glacier algal bloom was apparent during summer 2022, abundances ranged from 1.78 × 104 to 8.95 × 105 cells ml-1 of meltwater and did not scale linearly with the magnitude of the 2022 melt season. Instead, spatiotemporal heterogeneity in algal distribution across Morteratsch glacier leads us to propose melt-water-redistribution of (larger) glacier algal cells down-glacier and presumptive export of cells from the system as an important mechanism to set overall bloom carrying capacity on steep valley glaciers during high melt years. Despite the paradox of abundant glacier algae within seemingly oligotrophic surface ice, we found no evidence for inorganic nutrient limitation as an important bottom-up control within our study site, supporting our hypothesis above. Fundamental physical constraints may thus cap bloom carrying-capacities on valley glaciers as 21st century melting continues.
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Affiliation(s)
- Jasmin L Millar
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Emily L M Broadwell
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Madeleine Lewis
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
- British Antarctic Survey, Cambridge, United Kingdom
| | - Alexander M C Bowles
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Andrew J Tedstone
- Department of Geosciences, University of Fribourg, Fribourg, Switzerland
| | - Christopher J Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
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Doting EL, Jensen MB, Peter EK, Ellegaard-Jensen L, Tranter M, Benning LG, Hansen M, Anesio AM. The exometabolome of microbial communities inhabiting bare ice surfaces on the southern Greenland Ice Sheet. Environ Microbiol 2024; 26:e16574. [PMID: 38263628 DOI: 10.1111/1462-2920.16574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 12/20/2023] [Indexed: 01/25/2024]
Abstract
Microbial blooms colonize the Greenland Ice Sheet bare ice surface during the ablation season and significantly reduce its albedo. On the ice surface, microbes are exposed to high levels of irradiance, freeze-thaw cycles, and low nutrient concentrations. It is well known that microorganisms secrete metabolites to maintain homeostasis, communicate with other microorganisms, and defend themselves. Yet, the exometabolome of supraglacial microbial blooms, dominated by the pigmented glacier ice algae Ancylonema alaskanum and Ancylonema nordenskiöldii, remains thus far unstudied. Here, we use a high-resolution mass spectrometry-based untargeted metabolomics workflow to identify metabolites in the exometabolome of microbial blooms on the surface of the southern tip of the Greenland Ice Sheet. Samples were collected every 6 h across two diurnal cycles at 5 replicate sampling sites with high similarity in community composition, in terms of orders and phyla present. Time of sampling explained 46% (permutational multivariate analysis of variance [PERMANOVA], pseudo-F = 3.7771, p = 0.001) and 27% (PERMANOVA, pseudo-F = 1.8705, p = 0.001) of variance in the exometabolome across the two diurnal cycles. Annotated metabolites included riboflavin, lumichrome, tryptophan, and azelaic acid, all of which have demonstrated roles in microbe-microbe interactions in other ecosystems and should be tested for potential roles in the development of microbial blooms on bare ice surfaces.
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Affiliation(s)
- Eva L Doting
- Department of Environmental Science, iClimate, Aarhus University, Roskilde, Denmark
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Marie B Jensen
- Department of Environmental Science, iClimate, Aarhus University, Roskilde, Denmark
| | - Elisa K Peter
- Interface Geochemistry Section, German Research Centre for Geosciences, Potsdam, Germany
- Department of Earth Sciences, Freie Universität Berlin, Berlin, Germany
| | - Lea Ellegaard-Jensen
- Department of Environmental Science, iClimate, Aarhus University, Roskilde, Denmark
| | - Martyn Tranter
- Department of Environmental Science, iClimate, Aarhus University, Roskilde, Denmark
| | - Liane G Benning
- Interface Geochemistry Section, German Research Centre for Geosciences, Potsdam, Germany
- Department of Earth Sciences, Freie Universität Berlin, Berlin, Germany
| | - Martin Hansen
- Department of Environmental Science, iClimate, Aarhus University, Roskilde, Denmark
| | - Alexandre M Anesio
- Department of Environmental Science, iClimate, Aarhus University, Roskilde, Denmark
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Winkel M, Trivedi CB, Mourot R, Bradley JA, Vieth-Hillebrand A, Benning LG. Seasonality of Glacial Snow and Ice Microbial Communities. Front Microbiol 2022; 13:876848. [PMID: 35651494 PMCID: PMC9149292 DOI: 10.3389/fmicb.2022.876848] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 04/26/2022] [Indexed: 01/03/2023] Open
Abstract
Blooms of microalgae on glaciers and ice sheets are amplifying surface ice melting rates, which are already affected by climate change. Most studies on glacial microorganisms (including snow and glacier ice algae) have so far focused on the spring and summer melt season, leading to a temporal bias, and a knowledge gap in our understanding of the variations in microbial diversity, productivity, and physiology on glacier surfaces year-round. Here, we investigated the microbial communities from Icelandic glacier surface snow and bare ice habitats, with sampling spanning two consecutive years and carried out in both winter and two summer seasons. We evaluated the seasonal differences in microbial community composition using Illumina sequencing of the 16S rRNA, 18S rRNA, and ITS marker genes and correlating them with geochemical signals in the snow and ice. During summer, Chloromonas, Chlainomonas, Raphidonema, and Hydrurus dominated surface snow algal communities, while Ancylonema and Mesotaenium dominated the surface bare ice habitats. In winter, algae could not be detected, and the community composition was dominated by bacteria and fungi. The dominant bacterial taxa found in both winter and summer samples were Bacteriodetes, Actinobacteria, Alphaproteobacteria, and Gammaproteobacteria. The winter bacterial communities showed high similarities to airborne and fresh snow bacteria reported in other studies. This points toward the importance of dry and wet deposition as a wintertime source of microorganisms to the glacier surface. Winter samples were also richer in nutrients than summer samples, except for dissolved organic carbon-which was highest in summer snow and ice samples with blooming microalgae, suggesting that nutrients are accumulated during winter but primarily used by the microbial communities in the summer. Overall, our study shows that glacial snow and ice microbial communities are highly variable on a seasonal basis.
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Affiliation(s)
- Matthias Winkel
- GFZ German Research Centre for Geosciences, Helmholtz Centre for Geosciences, Potsdam, Germany
| | - Christopher B Trivedi
- GFZ German Research Centre for Geosciences, Helmholtz Centre for Geosciences, Potsdam, Germany
| | - Rey Mourot
- GFZ German Research Centre for Geosciences, Helmholtz Centre for Geosciences, Potsdam, Germany
| | - James A Bradley
- GFZ German Research Centre for Geosciences, Helmholtz Centre for Geosciences, Potsdam, Germany.,School of Geography, Queen Mary University of London, London, United Kingdom
| | - Andrea Vieth-Hillebrand
- GFZ German Research Centre for Geosciences, Helmholtz Centre for Geosciences, Potsdam, Germany
| | - Liane G Benning
- GFZ German Research Centre for Geosciences, Helmholtz Centre for Geosciences, Potsdam, Germany.,Department of Earth Sciences, Freie Universität Berlin, Berlin, Germany
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Perini L, Gostinčar C, Likar M, Frisvad JC, Kostanjšek R, Nicholes M, Williamson C, Anesio AM, Zalar P, Gunde-Cimerman N. Interactions of Fungi and Algae from the Greenland Ice Sheet. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02033-5. [PMID: 35608637 DOI: 10.1007/s00248-022-02033-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 05/03/2022] [Indexed: 06/15/2023]
Abstract
Heavily pigmented glacier ice algae Ancylonema nordenskiöldii and Ancylonema alaskanum (Zygnematophyceae, Streptophyta) reduce the bare ice albedo of the Greenland Ice Sheet, amplifying melt from the largest cryospheric contributor to eustatic sea-level rise. Little information is available about glacier ice algae interactions with other microbial communities within the surface ice environment, including fungi, which may be important for sustaining algal bloom development. To address this substantial knowledge gap and investigate the nature of algal-fungal interactions, an ex situ co-cultivation experiment with two species of fungi, recently isolated from the surface of the Greenland Ice Sheet (here proposed new species Penicillium anthracinoglaciei Perini, Frisvad and Zalar, Mycobank (MB 835602), and Articulospora sp.), and the mixed microbial community dominated by glacier ice algae was performed. The utilization of the dark pigment purpurogallin carboxylic acid-6-O-β-D-glucopyranoside (C18H18O12) by the two fungi was also evaluated in a separate experiment. P. anthracinoglaciei was capable of utilizing and converting the pigment to purpurogallin carboxylic acid, possibly using the sugar moiety as a nutrient source. Furthermore, after 3 weeks of incubation in the presence of P. anthracinoglaciei, a significantly slower decline in the maximum quantum efficiency (Fv/Fm, inverse proxy of algal stress) in glacier ice algae, compared to other treatments, was evident, suggesting a positive relationship between these species. Articulospora sp. did uptake the glycosylated purpurogallin, but did not seem to be involved in its conversion to aglycone derivative. At the end of the incubation experiments and, in conjunction with increased algal mortality, we detected a substantially increasing presence of the zoosporic fungi Chytridiomycota suggesting an important role for them as decomposers or parasites of glacier ice algae.
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Affiliation(s)
- L Perini
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia.
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark.
| | - C Gostinčar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
- Lars Bolund Institute of Regenerative Medicine, BGI-Qingdao, Qingdao, 266555, China
| | - M Likar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - J C Frisvad
- Department of Biotechnology and Biomedicine, Fungal Chemodiversity, Technical University of Denmark, Søltofts Plads, Building 221, 2800, Kgs. Lyngby, Denmark
| | - R Kostanjšek
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - M Nicholes
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, BS8 1SS, UK
| | - C Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, BS8 1SS, UK
| | - A M Anesio
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark
| | - P Zalar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - N Gunde-Cimerman
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
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Temporal Variability of Surface Reflectance Supersedes Spatial Resolution in Defining Greenland’s Bare-Ice Albedo. REMOTE SENSING 2021. [DOI: 10.3390/rs14010062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Ice surface albedo is a primary modulator of melt and runoff, yet our understanding of how reflectance varies over time across the Greenland Ice Sheet remains poor. This is due to a disconnect between point or transect scale albedo sampling and the coarser spatial, spectral and/or temporal resolutions of available satellite products. Here, we present time-series of bare-ice surface reflectance data that span a range of length scales, from the 500 m for Moderate Resolution Imaging Spectrometer’s MOD10A1 product, to 10 m for Sentinel-2 imagery, 0.1 m spot measurements from ground-based field spectrometry, and 2.5 cm from uncrewed aerial drone imagery. Our results reveal broad similarities in seasonal patterns in bare-ice reflectance, but further analysis identifies short-term dynamics in reflectance distribution that are unique to each dataset. Using these distributions, we demonstrate that areal mean reflectance is the primary control on local ablation rates, and that the spatial distribution of specific ice types and impurities is secondary. Given the rapid changes in mean reflectance observed in the datasets presented, we propose that albedo parameterizations can be improved by (i) quantitative assessment of the representativeness of time-averaged reflectance data products, and, (ii) using temporally-resolved functions to describe the variability in impurity distribution at daily time-scales. We conclude that the regional melt model performance may not be optimally improved by increased spatial resolution and the incorporation of sub-pixel heterogeneity, but instead, should focus on the temporal dynamics of bare-ice albedo.
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10
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Extremophilic Microorganisms in Central Europe. Microorganisms 2021; 9:microorganisms9112326. [PMID: 34835450 PMCID: PMC8620676 DOI: 10.3390/microorganisms9112326] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 11/17/2022] Open
Abstract
Extremophiles inhabit a wide variety of environments. Here we focus on extremophiles in moderate climates in central Europe, and particularly in Slovenia. Although multiple types of stress often occur in the same habitat, extremophiles are generally combined into groups according to the main stressor to which they are adapted. Several types of extremophiles, e.g., oligotrophs, are well represented and diverse in subsurface environments and karst regions. Psychrophiles thrive in ice caves and depressions with eternal snow and ice, with several globally distributed snow algae and psychrophilic bacteria that have been discovered in alpine glaciers. However, this area requires further research. Halophiles thrive in salterns while thermophiles inhabit thermal springs, although there is little data on such microorganisms in central Europe, despite many taxa being found globally. This review also includes the potential use of extremophiles in biotechnology and bioremediation applications.
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11
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Williamson CJ, Turpin-Jelfs T, Nicholes MJ, Yallop ML, Anesio AM, Tranter M. Macro-Nutrient Stoichiometry of Glacier Algae From the Southwestern Margin of the Greenland Ice Sheet. FRONTIERS IN PLANT SCIENCE 2021; 12:673614. [PMID: 34262580 PMCID: PMC8273243 DOI: 10.3389/fpls.2021.673614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 04/23/2021] [Indexed: 06/13/2023]
Abstract
Glacier algae residing within the surface ice of glaciers and ice sheets play globally significant roles in biogeochemical cycling, albedo feedbacks, and melt of the world's cryosphere. Here, we present an assessment of the macro-nutrient stoichiometry of glacier algal assemblages from the southwestern Greenland Ice Sheet (GrIS) margin, where widespread glacier algal blooms proliferate during summer melt seasons. Samples taken during the mid-2019 ablation season revealed overall lower cellular carbon (C), nitrogen (N), and phosphorus (P) content than predicted by standard microalgal cellular content:biovolume relationships, and elevated C:N and C:P ratios in all cases, with an overall estimated C:N:P of 1,997:73:1. We interpret lower cellular macro-nutrient content and elevated C:N and C:P ratios to reflect adaptation of glacier algal assemblages to their characteristic oligotrophic surface ice environment. Such lower macro-nutrient requirements would aid the proliferation of blooms across the nutrient poor cryosphere in a warming world. Up-scaling of our observations indicated the potential for glacier algal assemblages to accumulate ∼ 29 kg C km2 and ∼ 1.2 kg N km2 within our marginal surface ice location by the mid-ablation period (early August), confirming previous modeling estimates. While the long-term fate of glacier algal autochthonous production within surface ice remains unconstrained, data presented here provide insight into the possible quality of dissolved organic matter that may be released by assemblages into the surface ice environment.
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Affiliation(s)
- Christopher J. Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Thomas Turpin-Jelfs
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Miranda J. Nicholes
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Marian L. Yallop
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | | | - Martyn Tranter
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
- Department of Environmental Science, Aarhus University, Aarhus, Denmark
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12
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Irvine-Fynn TDL, Edwards A, Stevens IT, Mitchell AC, Bunting P, Box JE, Cameron KA, Cook JM, Naegeli K, Rassner SME, Ryan JC, Stibal M, Williamson CJ, Hubbard A. Storage and export of microbial biomass across the western Greenland Ice Sheet. Nat Commun 2021; 12:3960. [PMID: 34172727 PMCID: PMC8233322 DOI: 10.1038/s41467-021-24040-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 05/21/2021] [Indexed: 11/23/2022] Open
Abstract
The Greenland Ice Sheet harbours a wealth of microbial life, yet the total biomass stored or exported from its surface to downstream environments is unconstrained. Here, we quantify microbial abundance and cellular biomass flux within the near-surface weathering crust photic zone of the western sector of the ice sheet. Using groundwater techniques, we demonstrate that interstitial water flow is slow (~10−2 m d−1), while flow cytometry enumeration reveals this pathway delivers 5 × 108 cells m−2 d−1 to supraglacial streams, equivalent to a carbon flux up to 250 g km−2 d−1. We infer that cellular carbon accumulation in the weathering crust exceeds fluvial export, promoting biomass sequestration, enhanced carbon cycling, and biological albedo reduction. We estimate that up to 37 kg km−2 of cellular carbon is flushed from the weathering crust environment of the western Greenland Ice Sheet each summer, providing an appreciable flux to support heterotrophs and methanogenesis at the bed. Microbes that colonise ice sheet surfaces are important to the carbon cycle, but their biomass and transport remains unquantified. Here, the authors reveal substantial microbial carbon fluxes across Greenland’s ice surface, in quantities that may sustain subglacial heterotrophs and fuel methanogenesis.
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Affiliation(s)
- T D L Irvine-Fynn
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK.
| | - A Edwards
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
| | - I T Stevens
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK.,School of Geography, Politics and Sociology, Newcastle University, Newcastle-upon-Tyne, UK.,Department of Environmental Science, Aarhus University, Frederiksborgvej, Roskilde, Denmark
| | - A C Mitchell
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
| | - P Bunting
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
| | - J E Box
- Department of Glaciology and Climate, Geological Survey of Denmark and Greenland, Copenhagen, Denmark
| | - K A Cameron
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK.,Department of Glaciology and Climate, Geological Survey of Denmark and Greenland, Copenhagen, Denmark.,School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UK
| | - J M Cook
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK.,Department of Environmental Science, Aarhus University, Frederiksborgvej, Roskilde, Denmark.,Department of Geography, University of Sheffield, Sheffield, UK
| | - K Naegeli
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK.,Institute of Geography and Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
| | - S M E Rassner
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
| | - J C Ryan
- Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
| | - M Stibal
- Department of Ecology, Faculty of Science, Charles University, Prague, Czechia
| | - C J Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, UK
| | - A Hubbard
- Centre for Gas Hydrate, Environment and Climate, Department of Geosciences, UiT-The Arctic University of Norway, Tromsø, Norway.,Geography Research Unit, University of Oulu, Oulu, Finland
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13
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Procházková L, Řezanka T, Nedbalová L, Remias D. Unicellular versus Filamentous: The Glacial Alga Ancylonema alaskana comb. et stat. nov. and Its Ecophysiological Relatedness to Ancylonema nordenskioeldii (Zygnematophyceae, Streptophyta). Microorganisms 2021; 9:1103. [PMID: 34065466 PMCID: PMC8161032 DOI: 10.3390/microorganisms9051103] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/15/2021] [Accepted: 05/17/2021] [Indexed: 11/16/2022] Open
Abstract
Melting polar and alpine ice surfaces frequently exhibit blooms of dark pigmented algae. These microbial extremophiles significantly reduce the surface albedo of glaciers, thus accelerating melt rates. However, the ecology, physiology and taxonomy of cryoflora are not yet fully understood. Here, a Swiss and an Austrian glacier dominated either by filamentous Ancylonema nordenskioeldii or unicellular Mesotaenium berggrenii var. alaskanum, were sampled. Molecular analysis showed that both species are closely related, sharing identical chloroplast morphologies (parietal-lobed for Ancylonema vs. axial plate-like for Mesotaenium sensu stricto), thus the unicellular species was renamed Ancylonema alaskana. Moreover, an ecophysiological comparison of the two species was performed: pulse-amplitude modulated (PAM) fluorometry confirmed that they have a high tolerance to elevated solar irradiation, the physiological light preferences reflected the conditions in the original habitat; nonetheless, A. nordenskioeldii was adapted to higher irradiances while the photosystems of A. alaskana were able to use efficiently low irradiances. Additionally, the main vacuolar polyphenol, which effectively shields the photosystems, was identical in both species. Also, about half of the cellular fatty acids were polyunsaturated, and the lipidome profiles dominated by triacylglycerols were very similar. The results indicate that A. alaskana is physiologically very similar and closely related but genetically distinct to A. nordenskioeldii.
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Affiliation(s)
- Lenka Procházková
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, 128 44 Prague, Czech Republic;
| | - Tomáš Řezanka
- Institute of Microbiology, The Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic;
| | - Linda Nedbalová
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, 128 44 Prague, Czech Republic;
- Centre for Phycology, Institute of Botany of the Czech Academy of Sciences, Dukelská 135, 379 82 Třeboň, Czech Republic
| | - Daniel Remias
- School of Engineering, University of Applied Sciences Upper Austria, Stelzhamerstr. 23, 4600 Wels, Austria
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14
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Mineral phosphorus drives glacier algal blooms on the Greenland Ice Sheet. Nat Commun 2021; 12:570. [PMID: 33495440 PMCID: PMC7835244 DOI: 10.1038/s41467-020-20627-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 12/02/2020] [Indexed: 02/06/2023] Open
Abstract
Melting of the Greenland Ice Sheet is a leading cause of land-ice mass loss and cryosphere-attributed sea level rise. Blooms of pigmented glacier ice algae lower ice albedo and accelerate surface melting in the ice sheet’s southwest sector. Although glacier ice algae cause up to 13% of the surface melting in this region, the controls on bloom development remain poorly understood. Here we show a direct link between mineral phosphorus in surface ice and glacier ice algae biomass through the quantification of solid and fluid phase phosphorus reservoirs in surface habitats across the southwest ablation zone of the ice sheet. We demonstrate that nutrients from mineral dust likely drive glacier ice algal growth, and thereby identify mineral dust as a secondary control on ice sheet melting. Melting of the Greenland Ice Sheet—a threat for sea level rise—is accelerated by ice algal blooms. Here the authors find a link between mineral phosphorus and glacier algae, indicating that dust-derived nutrients aid bloom development, thereby impacting ice sheet melting.
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15
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Zawierucha K, Buda J, Jaromerska TN, Janko K, Gąsiorek P. Integrative approach reveals new species of water bears (Pilatobius, Grevenius, and Acutuncus) from Arctic cryoconite holes, with the discovery of hidden lineages of Hypsibius. ZOOL ANZ 2020. [DOI: 10.1016/j.jcz.2020.09.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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16
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Contrasting Patterns of Microbial Communities in Glacier Cryoconite of Nepali Himalaya and Greenland, Arctic. SUSTAINABILITY 2020. [DOI: 10.3390/su12166477] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
To understand the microbial composition and diversity patterns, cryoconite granules were collected from two geographical areas, i.e., Nepali Himalaya and Greenland, Arctic. 16S rRNA, ITS and the D1/D2 domain sequencing techniques were used for characterization of microbial communities of the four glaciers. The total 13 species of bacteria such as Bacillus aryabhattai, Bacillus simplex, Brevundimonas vesicularis, Cryobacterium luteum, Cryobacterium psychrotolerans, Dermacoccus nishinomiyaensis, Glaciihabitans tibetensis, Leifsonia kafniensis, Paracoccus limosus, Polaromonas glacialis, Sporosarcina globispora, Staphylococcus saprophyticus, Variovorax ginsengisoli, and 4 species of fungi such as Goffeauzyma gilvescens, Mrakia robertii, Dothideomycetes sp., Helotiales sp. were recorded from Nepali Himalaya. Among these, 12 species of bacteria and 4 species of fungi are new contributions to Himalaya. In contrast to this, six species of bacteria such as Bacillus cereus, Cryobacterium psychrotolerans, Dermacoccus nishinomiyaensis, Enhydrobacter aerosaccus, Glaciihabitans tibetensis, Subtercola frigoramans, and nine species of fungi such as Goffeauzyma gilvescens, Mrakia robertii, Naganishia vaughanmartiniae, Piskurozyma fildesensis, Rhodotorula svalbardensis, Alatospora acuminata, Articulospora sp., Phialophora sp., Thelebolus microspores, and Dothideomycetes sp.), were recorded from Qaanaaq, Isunnguata Sermia and Thule glaciers, Greenland. Among these, five species of bacteria and seven species of fungi are new contributions to Greenland cryoconite. Microbial analyses indicate that the Nepali Himalayan cryoconite colonize higher numbers of microbial species compared to the Greenland cryoconite.
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17
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Buda J, Łokas E, Pietryka M, Richter D, Magowski W, Iakovenko NS, Porazinska DL, Budzik T, Grabiec M, Grzesiak J, Klimaszyk P, Gaca P, Zawierucha K. Biotope and biocenosis of cryoconite hole ecosystems on Ecology Glacier in the maritime Antarctic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 724:138112. [PMID: 32408434 DOI: 10.1016/j.scitotenv.2020.138112] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 03/18/2020] [Accepted: 03/20/2020] [Indexed: 06/11/2023]
Abstract
Despite recent great interest in glacier ecosystems in the continental Antarctic, little is known about their maritime counterparts. Our study presents descriptive data on cryoconite sediments and cryoconite holes on Ecology Glacier (King George Island) to accomplish three main objectives: (a) to identify main eukaryotic (algae, invertebrates) and prokaryotic (cyanobacteria) components of microbial communities; (b) to provide a "baseline" of community composition, organic matter and artificial contamination; and (c) to identify key abiotic factors that might be important in community assembly. Cryoconite holes were sampled along an altitudinal gradient of Ecology Glacier in January, mid Austral Summer 2017. Cryoconite holes located in lower altitude were deeper than those located in the middle and the highest altitude. Seventeen species of algae and cyanobacteria with biomass of 0.79 to 5.37 μg/cm3 have been found in sediments. Dominant species were cyanobacterial Pseudanabaena frigida and Bacillariophyceae Microcostaus sp. Biomass of Bacillariophyceae was significantly higher than that of Chlorophyta and Cyanobacteria. We found three species of rotifers (potentially two new to science) and for the first time a glacier dwelling Acari (suspension feeder, Nanorchestes nivalis). Organic matter content ranged from 5.4% to 7.6%. Investigated artificial radionuclides included 137Cs, 238Pu, 239+240Pu and 241Am. 210Pb seems to be related to organic matter content. Overall, cryoconite holes on Ecology Glacier present unique habitats that serve as biodiversity hotspots of psychrophiles, source of organic matter, matrices for radioactivity tracking and model for observing changes in supraglacial ecosystems in the maritime Antarctic.
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Affiliation(s)
- Jakub Buda
- Department of Animal Taxonomy and Ecology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland
| | - Edyta Łokas
- Department of Mass Spectrometry, Institute of Nuclear Physics Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland
| | - Mirosława Pietryka
- Department of Botany and Plant Ecology, Wrocław University of Environmental and Life Science, pl. Grunwaldzki 24a, 50-363 Wrocław, Poland
| | - Dorota Richter
- Department of Botany and Plant Ecology, Wrocław University of Environmental and Life Science, pl. Grunwaldzki 24a, 50-363 Wrocław, Poland
| | - Wojciech Magowski
- Department of Animal Taxonomy and Ecology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland
| | - Nataliia S Iakovenko
- Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 129, CZ - 165 21 Praha 6, Suchdol, Czech Republic
| | - Dorota L Porazinska
- Department of Entomology and Nematology, University of Florida, Gainesville, FL, USA
| | - Tomasz Budzik
- Institute of Earth Sciences, University of Silesia in Katowice, Będzińska 60, 41-200 Sosnowiec, Poland
| | - Mariusz Grabiec
- Institute of Earth Sciences, University of Silesia in Katowice, Będzińska 60, 41-200 Sosnowiec, Poland
| | - Jakub Grzesiak
- Department of Antarctic Biology, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Piotr Klimaszyk
- Department of Water Protection, Faculty of Biology, Adam Mickiewicz University, 61-614 Poznań, Poland
| | - Paweł Gaca
- Ocean and Earth Science, University of Southampton, National Oceanography Centre, European Way, Southampton SO14 3ZH, United Kingdom
| | - Krzysztof Zawierucha
- Department of Animal Taxonomy and Ecology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614 Poznań, Poland.
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18
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Holland AT, Bergk Pinto B, Layton R, Williamson CJ, Anesio AM, Vogel TM, Larose C, Tranter M. Over Winter Microbial Processes in a Svalbard Snow Pack: An Experimental Approach. Front Microbiol 2020; 11:1029. [PMID: 32547512 PMCID: PMC7273115 DOI: 10.3389/fmicb.2020.01029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 04/27/2020] [Indexed: 11/25/2022] Open
Abstract
Snow packs cover large expanses of Earth’s land surface, making them integral components of the cryosphere in terms of past climate and atmospheric proxies, surface albedo regulators, insulators for other Arctic environments and habitats for diverse microbial communities such as algae, bacteria and fungi. Yet, most of our current understanding of snow pack environments, specifically microbial activity and community interaction, is limited to the main microbial growing season during spring ablation. At present, little is known about microbial activity and its influence on nutrient cycling during the subfreezing temperatures and 24-h darkness of the polar winter. Here, we examined microbial dynamics in a simulated cold (−5°C), dark snow pack to determine polar winter season microbial activity and its dependence on critical nutrients. Snow collected from Ny-Ålesund, Svalbard was incubated in the dark over a 5-week period with four different nutrient additions, including glacial mineral particles, dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP) and a combined treatment of DIN plus DIP. Data indicate a consumption of dissolved inorganic nutrients, particularly DIN, by heterotrophic communities, suggesting a potential nitrogen limitation, contradictory to phosphorus limitations found in most aquatic environments. 16S amplicon sequencing also reveal a clear difference in microbial community composition in the particulate mineral treatment compared to dissolved nutrient treatments and controls, suggesting that certain species of heterotrophs living within the snow pack are more likely to associate with particulates. Particulate phosphorus analyses indicate a potential ability of heterotrophic communities to access particulate sources of phosphorous, possibly explaining the lack of phosphorus limitation. These findings have importance for understanding microbial activity during the polar winter season and its potential influences on the abundance and bioavailability of nutrients released to surface ice and downstream environments during the ablation season.
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Affiliation(s)
- Alexandra T Holland
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Benoît Bergk Pinto
- Environmental Microbial Genomics, CNRS, École Centrale de Lyon, Université de Lyon, Lyon, France
| | - Rose Layton
- Environmental Microbial Genomics, CNRS, École Centrale de Lyon, Université de Lyon, Lyon, France.,ENOVEO, Lyon, France
| | - Christopher J Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Alexandre M Anesio
- Department of Environmental Science, Aarhus University, Copenhagen, Denmark
| | - Timothy M Vogel
- Environmental Microbial Genomics, CNRS, École Centrale de Lyon, Université de Lyon, Lyon, France
| | - Catherine Larose
- Environmental Microbial Genomics, CNRS, École Centrale de Lyon, Université de Lyon, Lyon, France
| | - Martyn Tranter
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
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19
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Edwards A, Cameron KA, Cook JM, Debbonaire AR, Furness E, Hay MC, Rassner SM. Microbial genomics amidst the Arctic crisis. Microb Genom 2020; 6:e000375. [PMID: 32392124 PMCID: PMC7371112 DOI: 10.1099/mgen.0.000375] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 04/16/2020] [Indexed: 12/16/2022] Open
Abstract
The Arctic is warming - fast. Microbes in the Arctic play pivotal roles in feedbacks that magnify the impacts of Arctic change. Understanding the genome evolution, diversity and dynamics of Arctic microbes can provide insights relevant for both fundamental microbiology and interdisciplinary Arctic science. Within this synthesis, we highlight four key areas where genomic insights to the microbial dimensions of Arctic change are urgently required: the changing Arctic Ocean, greenhouse gas release from the thawing permafrost, 'biological darkening' of glacial surfaces, and human activities within the Arctic. Furthermore, we identify four principal challenges that provide opportunities for timely innovation in Arctic microbial genomics. These range from insufficient genomic data to develop unifying concepts or model organisms for Arctic microbiology to challenges in gaining authentic insights to the structure and function of low-biomass microbiota and integration of data on the causes and consequences of microbial feedbacks across scales. We contend that our insights to date on the genomics of Arctic microbes are limited in these key areas, and we identify priorities and new ways of working to help ensure microbial genomics is in the vanguard of the scientific response to the Arctic crisis.
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Affiliation(s)
- Arwyn Edwards
- Interdisciplinary Centre for Environmental Microbiology, Institute of Biological, Environmental and Rural Sciences, Cledwyn Building, Aberystwyth University, Cymru SY23 3DD, UK
| | - Karen A. Cameron
- Interdisciplinary Centre for Environmental Microbiology, Institute of Biological, Environmental and Rural Sciences, Cledwyn Building, Aberystwyth University, Cymru SY23 3DD, UK
| | - Joseph M. Cook
- Interdisciplinary Centre for Environmental Microbiology, Institute of Biological, Environmental and Rural Sciences, Cledwyn Building, Aberystwyth University, Cymru SY23 3DD, UK
| | - Aliyah R. Debbonaire
- Interdisciplinary Centre for Environmental Microbiology, Institute of Biological, Environmental and Rural Sciences, Cledwyn Building, Aberystwyth University, Cymru SY23 3DD, UK
| | - Eleanor Furness
- Interdisciplinary Centre for Environmental Microbiology, Institute of Biological, Environmental and Rural Sciences, Cledwyn Building, Aberystwyth University, Cymru SY23 3DD, UK
| | - Melanie C. Hay
- Interdisciplinary Centre for Environmental Microbiology, Institute of Biological, Environmental and Rural Sciences, Cledwyn Building, Aberystwyth University, Cymru SY23 3DD, UK
| | - Sara M.E. Rassner
- Interdisciplinary Centre for Environmental Microbiology, Institute of Biological, Environmental and Rural Sciences, Cledwyn Building, Aberystwyth University, Cymru SY23 3DD, UK
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20
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Glacier algae foster ice-albedo feedback in the European Alps. Sci Rep 2020; 10:4739. [PMID: 32179790 PMCID: PMC7075879 DOI: 10.1038/s41598-020-61762-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/18/2020] [Indexed: 01/25/2023] Open
Abstract
The melting of glaciers and ice sheets is nowadays considered a symbol of climate change. Many complex mechanisms are involved in the melting of ice, and, among these processes, surface darkening due to organic material on bare ice has recently received attention from the scientific community. The presence of microbes on glaciers has been shown to decrease the albedo of ice and promote melting. Despite several studies from the Himalaya, Greenland, Andes, and Alaska, no quantitative studies have yet been conducted in the European Alps. In this paper, we made use of DNA sequencing, microscopy and field spectroscopy to describe the nature of glacier algae found at a glacier (Vadret da Morteratsch) of the European Alps and to evaluate their effect on the ice-albedo feedback. Among different algal species identified in the samples, we found a remarkable abundance of Ancylonema nordenskioeldii, a species that has never previously been quantitatively documented in the Alps and that dominates algal blooms on the Greenland Ice Sheet. Our results show that, at the end of the ablation season, the concentration of Ancylonema nordenskioeldii on the glacier surface is higher than that of other algal species (i.e. Mesotaenium berggrenii). Using field spectroscopy data, we identified a significant correlation between a reflectance ratio (750 nm/650 nm) and the algae concentration. This reflectance ratio could be useful for future mapping of glacier algae from remote sensing data exploiting band 6 (740 nm) and band 4 (665 nm) of the MultiSpectral Instrument (MSI) on board Sentinel-2 satellite. Here we show that the biological darkening of glaciers (i.e. the bioalbedo feedback) is also occurring in the European Alps, and thus it is a global process that must be taken into account when considering the positive feedback mechanisms related to glacier melting.
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21
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Abstract
Processes that darken the surface of the Greenland Ice Sheet (GrIS) enhance energy absorption and accelerate melt, with consequences for global sea-level rise. Here, we demonstrate how summer blooms of “glacier algae” darken the ice surface, significantly impacting the physical integrity of the environment. We identify and quantify the energy regulation mechanisms employed by glacier algae to balance their requirements for photosynthesis and growth with the extreme light and temperature regime of the GrIS, demonstrating how these mechanisms are optimized to darken and melt the ice surface. Our findings are critical for the incorporation of biological feedbacks into predictive models of GrIS surface runoff and provide unique insight into how photoautotrophic life excels within icy environments. Blooms of Zygnematophycean “glacier algae” lower the bare ice albedo of the Greenland Ice Sheet (GrIS), amplifying summer energy absorption at the ice surface and enhancing meltwater runoff from the largest cryospheric contributor to contemporary sea-level rise. Here, we provide a step change in current understanding of algal-driven ice sheet darkening through quantification of the photophysiological mechanisms that allow glacier algae to thrive on and darken the bare ice surface. Significant secondary phenolic pigmentation (11 times the cellular content of chlorophyll a) enables glacier algae to tolerate extreme irradiance (up to ∼4,000 µmol photons⋅m−2⋅s−1) while simultaneously repurposing captured ultraviolet and short-wave radiation for melt generation. Total cellular energy absorption is increased 50-fold by phenolic pigmentation, while glacier algal chloroplasts positioned beneath shading pigments remain low-light–adapted (Ek ∼46 µmol photons⋅m−2⋅s−1) and dependent upon typical nonphotochemical quenching mechanisms for photoregulation. On the GrIS, glacier algae direct only ∼1 to 2.4% of incident energy to photochemistry versus 48 to 65% to ice surface melting, contributing an additional ∼1.86 cm water equivalent surface melt per day in patches of high algal abundance (∼104 cells⋅mL−1). At the regional scale, surface darkening is driven by the direct and indirect impacts of glacier algae on ice albedo, with a significant negative relationship between broadband albedo (Moderate Resolution Imaging Spectroradiometer [MODIS]) and glacier algal biomass (R2 = 0.75, n = 149), indicating that up to 75% of the variability in albedo across the southwestern GrIS may be attributable to the presence of glacier algae.
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22
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Wadham JL, Hawkings JR, Tarasov L, Gregoire LJ, Spencer RGM, Gutjahr M, Ridgwell A, Kohfeld KE. Ice sheets matter for the global carbon cycle. Nat Commun 2019; 10:3567. [PMID: 31417076 PMCID: PMC6695407 DOI: 10.1038/s41467-019-11394-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 07/09/2019] [Indexed: 11/09/2022] Open
Abstract
The cycling of carbon on Earth exerts a fundamental influence upon the greenhouse gas content of the atmosphere, and hence global climate over millennia. Until recently, ice sheets were viewed as inert components of this cycle and largely disregarded in global models. Research in the past decade has transformed this view, demonstrating the existence of uniquely adapted microbial communities, high rates of biogeochemical/physical weathering in ice sheets and storage and cycling of organic carbon (>104 Pg C) and nutrients. Here we assess the active role of ice sheets in the global carbon cycle and potential ramifications of enhanced melt and ice discharge in a warming world.
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Affiliation(s)
- J L Wadham
- University of Bristol, Bristol, BS8 1TH, UK.
| | - J R Hawkings
- National High Magnetic Field Lab and Earth, Ocean and Atmospheric Sciences, Florida State University, Tallahassee, FL, 32306, USA
- German Research Centre for Geosciences GFZ, 14473, Potsdam, Germany
| | - L Tarasov
- Memorial University, St. John's, NF, A1B 3X9, Canada
| | | | - R G M Spencer
- National High Magnetic Field Lab and Earth, Ocean and Atmospheric Sciences, Florida State University, Tallahassee, FL, 32306, USA
| | | | - A Ridgwell
- University of California, Riverside, CA, 94720, USA
| | - K E Kohfeld
- Simon Fraser University, Burnaby, BC, 8888, Canada
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23
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Nicholes MJ, Williamson CJ, Tranter M, Holland A, Poniecka E, Yallop ML, Anesio A. Bacterial Dynamics in Supraglacial Habitats of the Greenland Ice Sheet. Front Microbiol 2019; 10:1366. [PMID: 31333595 PMCID: PMC6616251 DOI: 10.3389/fmicb.2019.01366] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/31/2019] [Indexed: 11/13/2022] Open
Abstract
Current research into bacterial dynamics on the Greenland Ice Sheet (GrIS) is biased toward cryoconite holes, despite this habitat covering less than 8% of the ablation (melt) zone surface. In contrast, the expansive surface ice, which supports wide-spread Streptophyte micro-algal blooms thought to enhance surface melt, has been relatively neglected. This study aims to understand variability in bacterial abundance and production across an ablation season on the GrIS, in relation to micro-algal bloom dynamics. Bacterial abundance reached 3.3 ± 0.3 × 105 cells ml−1 in surface ice and was significantly linearly related to algal abundances during the middle and late ablation periods (R2 = 0.62, p < 0.05; R2 = 0.78, p < 0.001). Bacterial production (BP) of 0.03–0.6 μg C L−1 h−1 was observed in surface ice and increased in concert with glacier algal abundances, indicating that heterotrophic bacteria consume algal-derived dissolved organic carbon. However, BP remained at least 28 times lower than net primary production, indicating inefficient carbon cycling by heterotrophic bacteria and net accumulation of carbon in surface ice throughout the ablation season. Across the supraglacial environment, cryoconite sediment BP was at least four times greater than surface ice, confirming that cryoconite holes are the true “hot spots” of heterotrophic bacterial activity.
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Affiliation(s)
- Miranda Jane Nicholes
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Christopher James Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom.,School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - Martyn Tranter
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Alexandra Holland
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Ewa Poniecka
- School of Earth and Ocean Sciences, Cardiff University, Cardiff, United Kingdom
| | - Marian Louise Yallop
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom.,School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | | | - Alexandre Anesio
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom.,Department of Environmental Science, Aarhus University, Roskilde, Denmark
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Williamson CJ, Cameron KA, Cook JM, Zarsky JD, Stibal M, Edwards A. Glacier Algae: A Dark Past and a Darker Future. Front Microbiol 2019; 10:524. [PMID: 31019491 PMCID: PMC6458304 DOI: 10.3389/fmicb.2019.00524] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 02/28/2019] [Indexed: 11/13/2022] Open
Abstract
"Glacier algae" grow on melting glacier and ice sheet surfaces across the cryosphere, causing the ice to absorb more solar energy and consequently melt faster, while also turning over carbon and nutrients. This makes glacier algal assemblages, which are typically dominated by just three main species, a potentially important yet under-researched component of the global biosphere, carbon, and water cycles. This review synthesizes current knowledge on glacier algae phylogenetics, physiology, and ecology. We discuss their significance for the evolution of early land plants and highlight their impacts on the physical and chemical supraglacial environment including their role as drivers of positive feedbacks to climate warming, thereby demonstrating their influence on Earth's past and future. Four complementary research priorities are identified, which will facilitate broad advances in glacier algae research, including establishment of reliable culture collections, sequencing of glacier algae genomes, development of diagnostic biosignatures for remote sensing, and improved predictive modeling of glacier algae biological-albedo effects.
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Affiliation(s)
- Christopher J Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Karen A Cameron
- Institute of Biological, Environmental & Rural Sciences, Aberystwyth University, Aberystwyth, United Kingdom
| | - Joseph M Cook
- Department of Geography, The University of Sheffield, Sheffield, United Kingdom
| | - Jakub D Zarsky
- Department of Ecology, Faculty of Science, Charles University, Prague, Czechia
| | - Marek Stibal
- Department of Ecology, Faculty of Science, Charles University, Prague, Czechia
| | - Arwyn Edwards
- Institute of Biological, Environmental & Rural Sciences, Aberystwyth University, Aberystwyth, United Kingdom
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25
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Perini L, Gostinčar C, Anesio AM, Williamson C, Tranter M, Gunde-Cimerman N. Darkening of the Greenland Ice Sheet: Fungal Abundance and Diversity Are Associated With Algal Bloom. Front Microbiol 2019; 10:557. [PMID: 30949152 PMCID: PMC6437116 DOI: 10.3389/fmicb.2019.00557] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 03/04/2019] [Indexed: 01/16/2023] Open
Abstract
Recent studies have highlighted the importance of ice-algal blooms in driving darkening and therefore surface melt of the Greenland Ice Sheet (GrIS). However, the contribution of fungal and bacterial communities to this microbially driven albedo reduction remains unconstrained. To address this significant knowledge gap, fungi were isolated from key GrIS surface habitats (surface ice containing varying abundance of ice algae, supraglacial water, cryoconite holes, and snow), and a combination of cultivation and sequencing methods utilized to characterize the algal-associated fungal and bacterial diversity and abundance. Six hundred and ninety-seven taxa of fungi were obtained by amplicon sequencing and more than 200 fungal cultures belonging to 46 different species were isolated through cultivation approaches. Basidiomycota dominated in surface ice and water samples, and Ascomycota in snow samples. Amplicon sequencing revealed that bacteria were characterized by a higher diversity (883 taxa detected). Results from cultivation as well as ergosterol analyses suggested that surface ice dominated by ice algae and cryoconite holes supported the highest fungal biomass (104-105 CFU/100 ml) and that many fungal taxa recognized as endophytes and plant pathogens were associated with dark ice characterized by a high abundance of ice algae. This paper significantly advances this field of research by investigating for the first time the fungal abundance and diversity associated with algal blooms causing the darkening of the GrIS. There is a strong association between the abundance and diversity of fungal species and the blooming of algae on the surface ice of the Greenland Ice Sheet.
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Affiliation(s)
- Laura Perini
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Cene Gostinčar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Alexandre Magno Anesio
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
- Department of Environmental Science, Aarhus University, Roskilde, Denmark
| | - Christopher Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Martyn Tranter
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, United Kingdom
| | - Nina Gunde-Cimerman
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
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26
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Ryan JC, Smith LC, van As D, Cooley SW, Cooper MG, Pitcher LH, Hubbard A. Greenland Ice Sheet surface melt amplified by snowline migration and bare ice exposure. SCIENCE ADVANCES 2019; 5:eaav3738. [PMID: 30854432 PMCID: PMC6402853 DOI: 10.1126/sciadv.aav3738] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 01/27/2019] [Indexed: 06/09/2023]
Abstract
Greenland Ice Sheet mass loss has recently increased because of enhanced surface melt and runoff. Since melt is critically modulated by surface albedo, understanding the processes and feedbacks that alter albedo is a prerequisite for accurately forecasting mass loss. Using satellite imagery, we demonstrate the importance of Greenland's seasonally fluctuating snowline, which reduces ice sheet albedo and enhances melt by exposing dark bare ice. From 2001 to 2017, this process drove 53% of net shortwave radiation variability in the ablation zone and amplified ice sheet melt five times more than hydrological and biological processes that darken bare ice itself. In a warmer climate, snowline fluctuations will exert an even greater control on melt due to flatter ice sheet topography at higher elevations. Current climate models, however, inaccurately predict snowline elevations during high melt years, portending an unforeseen uncertainty in forecasts of Greenland's runoff contribution to global sea level rise.
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Affiliation(s)
- J. C. Ryan
- Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
- Department of Geography, University of California, Los Angeles, Los Angeles, CA, USA
| | - L. C. Smith
- Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
- Department of Geography, University of California, Los Angeles, Los Angeles, CA, USA
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, USA
| | - D. van As
- Geological Survey of Denmark and Greenland, Copenhagen, Denmark
| | - S. W. Cooley
- Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, USA
| | - M. G. Cooper
- Department of Geography, University of California, Los Angeles, Los Angeles, CA, USA
| | - L. H Pitcher
- Department of Geography, University of California, Los Angeles, Los Angeles, CA, USA
| | - A. Hubbard
- Centre for Glaciology, Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
- Centre for Arctic Gas Hydrate, Environment and Climate, Department of Geology, University of Tromsø, Tromsø 9037, Norway
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27
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Stibal M, Jacobsen CS, Häggblom MM. Editorial: Polar and Alpine Microbiology. FEMS Microbiol Ecol 2018; 94:5054038. [DOI: 10.1093/femsec/fiy136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 07/13/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Marek Stibal
- Department of Ecology, Faculty of Science, Charles University, 128 44 Prague, Czechia
| | | | - Max M Häggblom
- Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ 08901-8525, USA
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