A5086986016- Polar Research and Ecology
- Cryospheric studies and observations
- Microbial Community Ecology and Physiology
- Climate change and permafrost
- Geology and Paleoclimatology Research
- Marine and coastal ecosystems
- Bacteriophages and microbial interactions
- Winter Sports Injuries and Performance
- Methane Hydrates and Related Phenomena
- Biocrusts and Microbial Ecology
- Genomics and Phylogenetic Studies
- Marine Biology and Ecology Research
- Aquatic Ecosystems and Phytoplankton Dynamics
- Protist diversity and phylogeny
- Atmospheric and Environmental Gas Dynamics
- Algal biology and biofuel production
- Water Quality Monitoring and Analysis
- Isotope Analysis in Ecology
- Geophysics and Gravity Measurements
- Atmospheric chemistry and aerosols
- Planetary Science and Exploration
- Arctic and Antarctic ice dynamics
- Space Science and Extraterrestrial Life
- Spaceflight effects on biology
- Marine and fisheries research
Aarhus University
2018-2025
Roskilde University
2023
GFZ Helmholtz Centre for Geosciences
2023
University of Bristol
2010-2019
Universität Innsbruck
2015
Cabot (United States)
2010-2014
At Bristol
1999-2012
Aberystwyth University
2005-2008
University of Wales
2006-2007
University of Nottingham
2004
There is now compelling evidence that microbially mediated reactions impart a significant effect upon the dynamics, composition, and abundance of nutrients in glacial melt water. Consequently, we must consider ice masses as ecosystem habitats their own right address diversity, functional potential, activity part alpine polar environments. Although such research already underway, its fragmentary nature provides little basis for developing modern concepts glacier ecology. This paper therefore...
Abstract Cryoconite holes, which can cover 0.1–10% of the surface area glaciers, are small, water‐filled depressions (typically <1 m in diameter and usually <0.5 deep) that form on glaciers when solar‐heated inorganic organic debris melts into ice. Recent studies show cryoconites colonized by a diverse range microorganisms, including viruses, bacteria algae. Whether microbial communities actively influencing biogeochemical cycles or just present dormant state has been matter debate for...
Glaciers and ice sheets, like other biomes, occupy a significant area of the planet harbour biological communities with distinct interactions feedbacks their physical chemical environment. In case glacial biome, processes are dominated almost exclusively by microbial communities. Habitats on glaciers sheets enough liquid water to sustain activity include snow, surface ice, cryoconite holes, englacial systems interface between overridden rock/soil. There is remarkable similarity different...
Abstract The Arctic is melting at an unprecedented rate and key drivers are changes in snow ice albedo. Here we show that red snow, a common algal habitat blooming after the onset of melting, plays crucial role decreasing Our data reveal pigmented algae cosmopolitan as well independent location-specific geochemical mineralogical factors. patterns for diversity, pigmentation and, consequently albedo, ubiquitous across reduction albedo accelerates melt increases time area exposed bare ice. We...
Abstract. Sunlight penetrates the bare-ice surface of glaciers and ice sheets, giving rise to presence a three-dimensional porous matrix partially melted crystals known as weathering crust. Surface meltwater slowly percolates through this crust, which hosts active diverse bacterial communities, until it reaches supraglacial stream. Despite potential implications crust dynamics for glacial melting export carbon nutrients downstream ecosystems, its role in biogeochemical cycling remains...
We have assessed the microbial ecology on surface of Mittivakkat glacier in SE-Greenland during exceptional high melting season July 2012 when so far most extreme rate for Greenland Ice Sheet has been recorded. By employing a complementary and multi-disciplinary field sampling analytical approach, we quantified dramatic changes different habitats (green snow, red biofilms, grey ice, cryoconite holes). The observed clear change dominant algal community their rapidly changing cryo-organic...
Abstract. Melting of the Greenland Ice Sheet (GrIS) is largest single contributor to eustatic sea level and amplified by growth pigmented algae on ice surface, which increases solar radiation absorption. This biological albedo-reducing effect its impact upon rise has not previously been quantified. Here, we combine field spectroscopy with a radiative-transfer model, supervised classification unmanned aerial vehicle (UAV) satellite remote-sensing data, runoff modelling calculate biologically...
Blooms of Zygnematophycean “glacier algae” lower the bare ice albedo Greenland Ice Sheet (GrIS), amplifying summer energy absorption at surface and enhancing meltwater runoff from largest cryospheric contributor to contemporary sea-level rise. Here, we provide a step change in current understanding algal-driven sheet darkening through quantification photophysiological mechanisms that allow glacier algae thrive on darken surface. Significant secondary phenolic pigmentation (11 times cellular...
[1] Glacier surfaces contain a wide diversity of microorganisms and can host range microbial activities. However, nutrient cycling on glaciers is poorly understood. This study the first to document nitrogen fixation (nitrogenase activity) demonstrate its importance in supporting growth. Rates cryoconite holes three valley Svalbard ranged from <2.0 99.9 μmol ethylene m−2 d−1 with rates inversely correlated concentrations available inorganic nitrogen. Annual inputs by glacier catchment scale...
Abstract Subglacial environments are largely anoxic, contain organic carbon ( OC ) overridden by glacier ice during periods of advance, and harbour active microbial communities. This creates favourable conditions for degradation via methanogenesis. It has been hypothesized that beneath sheets is converted to methane CH 4 may be released the atmosphere retreat. However, there limited data available support this contention. Here, we present new on abundance, diversity activity methanogenic...
Distinct microbial habitats on glacial surfaces are dominated by snow and ice algae, which the critical players dominant primary colonisers net producers during melt season. Here for first time we have evaluated role of these algae in association with full community composition (i.e., bacteria, archaea) distinct surface 12 glaciers permanent fields Svalbard Arctic Sweden. We cross-correlated data analyses specific metabolites such as fatty acids pigments, a suite potential physico-chemical...
Aquatic dissolved organic matter (DOM) plays an essential role in biogeochemical cycling and transport of throughout the hydrological continuum. To characterise microbially-derived (OM) from common environmental microorganisms (Escherichia coli, Bacillus subtilis Pseudomonas aeruginosa), excitation-emission matrix (EEM) fluorescence spectroscopy was employed. This work shows that bacterial organisms can produce fluorescent (FOM) situ and, furthermore, production FOM differs at a species...
Algae are important primary colonizers of snow and glacial ice, but hitherto little is known about their ecology on Iceland's glaciers ice caps. Due do the close proximity active volcanoes delivering large amounts ash dust, they special ecosystems. This study provides first investigation presence diversity microbial communities all major Icelandic caps over a 3 year period. Using high-throughput sequencing small subunit ribosomal RNA genes (16S 18S), we assessed community structure...
Abstract Melting of the Greenland Ice Sheet is a leading cause land-ice mass loss and cryosphere-attributed sea level rise. Blooms pigmented glacier ice algae lower albedo accelerate surface melting in sheet’s southwest sector. Although up to 13% this region, controls on bloom development remain poorly understood. Here we show direct link between mineral phosphorus biomass through quantification solid fluid phase reservoirs habitats across ablation zone sheet. We demonstrate that nutrients...
Cryoconite holes are known as foci of microbial diversity and activity on polar glacier surfaces, but virtually unexplored habitats in alpine regions. In addition, whether cryoconite community structure reflects ecosystem functionality is poorly understood. Terminal restriction fragment length polymorphism Fourier transform infrared metabolite fingerprinting from glaciers Austria, Greenland Svalbard demonstrated bacterial communities closely correlated with cognate fingerprints. The...
Cyanobacteria are major primary producers in extreme cold ecosystems. Many lineages of cyanobacteria thrive these harsh environments, but it is not fully understood how they survive conditions and whether have evolved specific mechanisms adaptation. Phormidesmis priestleyi a cyanobacterium found throughout the biosphere (Arctic, Antarctic alpine habitats). Genome sequencing P. BC1401, an isolate from cryoconite hole on Greenland Ice Sheet, has allowed for examination genes involved shock...