Article
Ecology
Yong Zhou, Arielle Biro, Michelle Y. Wong, Sarah A. Batterman, A. Carla Staver
Summary: The biogeochemical signature of fire affects the functioning of ecosystems by altering soil extracellular enzyme activities (EEAs) and nutrient cycles. Fire reduces EEAs by decreasing soil microbial biomass and organic matter substrates, resulting in a slower microbially mediated nutrient cycle, particularly for phosphorus. These effects may become increasingly important as fire frequency and severity continue to change in response to global change.
Article
Environmental Sciences
John Chetelat, Melissa A. McKinney, Marc Amyot, Ashu Dastoor, Thomas A. Douglas, Lars-Eric Heimburger-Boavida, Jane Kirk, Kimmo K. Kahilainen, Peter M. Outridge, Nicolas Pelletier, Henrik Skov, Kyra St Pierre, Jussi Vuorenmaa, Feiyue Wang
Summary: This review summarizes the latest scientific research on how climate change affects the transport and biogeochemical cycling of mercury in Arctic terrestrial, freshwater, and marine ecosystems. The review emphasizes the profound shifts in climate and cryosphere in the Arctic and their connections to mercury cycling.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Ecology
Benoit Pasquier, Mark Holzer, Matthew A. Chamberlain, Richard J. Matear, Nathaniel L. Bindoff, Francois W. Primeau
Summary: Accurate predictive modeling of the ocean's global carbon and oxygen cycles is challenging due to uncertainties in biogeochemistry and ocean circulation. Parameter optimization allows models to better match observed biogeochemical fields, but may not fully capture the inner workings of the biological pump when fitting a model to observed tracers with known biases in circulation.
Article
Engineering, Environmental
Sydney C. Clark, Rebecca T. Barnes, Isabella A. Oleksy, Jill S. Baron, Meredith G. Hastings
Summary: Despite declining trends in atmospherically deposited nitrate since 2000, nitrate concentrations in high-elevation lakes of the Colorado Front Range remain elevated. The sources of elevated nitrate in surface waters include atmospheric deposition, glacial inputs, and nitrification within the catchment. The study results suggest that during the summer open-water season, alpine lakes receive a consistent contribution of uncycled atmospheric nitrate and nitrification plays a significant role in nitrate production within the catchment.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Environmental Sciences
Michaela L. de Melo, Marie-Laure Gerardin, Caroline Fink-Mercier, Paul A. del Giorgio
Summary: The Eastern James Bay has experienced significant changes in its physical, chemical, and ecological functioning due to climate and landscape changes as well as human intervention. Rivers play a crucial role in the Bay by delivering freshwater, key materials, and environmental signals. The study examines the spatial variability of riverine export fluxes and yields of various substances in the Eastern James Bay, identifying the main drivers of material concentrations and modeling their contribution to the regional budget. The findings highlight the impact of damming and climate change on water and material export from boreal rivers to the Bay.
Article
Biodiversity Conservation
Andrew J. Abraham, Andrea B. Webster, Tomos O. Prys-Jones, Elizabeth le Roux, Dylan Smith, Duncan McFayden, Pieter C. de Jager, Marcus Clauss, Christopher E. Doughty
Summary: Animals concentrate key nutrients in their bodies, and the removal of animals from fenced wildlife reserves can lead to significant loss of nutrients for the ecosystem. Faecal P concentrations can serve as an indicator of potential nutrient stress in the system. Natural predation is a sufficient mechanism to mitigate the need for wildlife removal and prevent nutrient loss.
JOURNAL OF APPLIED ECOLOGY
(2021)
Article
Geosciences, Multidisciplinary
William Kochtitzky, Luke Copland, Michalea King, Romain Hugonnet, Hester Jiskoot, Mathieu Morlighem, Romain Millan, Shfaqat Abbas Khan, Brice Noel
Summary: In Greenland, 87% of the glacierized area terminates in the ocean. The mass lost at the ice-ocean interface, or frontal ablation, is calculated to be 481.8 +/- 24.0 Gt a(-1) for 2000-2010 and 510.2 +/- 18.6 Gt a(-1) for 2010-2020. Ice discharge accounts for about 90% of frontal ablation, while terminus retreat contributes to the rest. Only 16 glaciers were responsible for the majority of frontal ablation from 2010 to 2020. These estimates provide a more comprehensive understanding of Greenland's ice sheet and peripheral glacier mass balance, and indicate that Greenland accounted for around 90% of Northern Hemisphere frontal ablation during the study periods.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
C. A. Ross, A. K. Phillips, L. Gospodyn, C. J. Oswald, C. C. Wellen, R. J. Sorichetti
Summary: This study aimed to improve the prediction of nutrient fluxes from agricultural streams in southern Ontario by improving the representation of water source contributions to streamflow in generalized additive models. By calibrating a recursive digital filter using stable isotopes of oxygen in water, the accuracy of baseflow estimates was significantly improved. The revised model provided a more accurate prediction of nutrient losses from the agricultural watersheds.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Marine & Freshwater Biology
Robert S. Nichols, Molly A. Moynihan, Patrick Martin
Summary: Coral reef productivity is influenced by organic matter breakdown, and alkaline phosphatases play a crucial role in marine phosphorus cycling. However, the factors affecting alkaline phosphatase activity (APA) in coastal waters are not well known. The study measured APA in bulk seawater and three coral species in Singapore, finding that seawater APA was driven by heterotrophic activity rather than phosphate stress, and corals had the potential to significantly contribute to seawater APA.
Article
Geochemistry & Geophysics
Destin Nziengui-Ba, Olivier Coutant, Ludovic Moreau, Pierre Boue
Summary: We investigated the potential of fibre optics coupled with distributed acoustic sensing (DAS) for measuring ice layer thickness and Young's modulus using guided seismic waves. Through field measurements and Bayesian inversion, we obtained accurate results for ice thickness and Young's modulus, which were consistent with field observations. The use of DAS to record guided seismic waves could be a valuable tool for monitoring environments such as floating ice shelves and sea ice.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Review
Agriculture, Dairy & Animal Science
S. L. Kronberg, F. D. Provenza, S. van Vliet, S. N. Young
Summary: To meet the challenge of producing large amounts of healthful animal and plant foods while maintaining ecosystem services and conserving essential nutrients, increased research on-farm and at the watershed scale is necessary. Collaboration with diverse interdisciplinary teams is crucial to develop innovative solutions and utilize a combination of techniques linked to agroecology and industrial ecology. Recycling nutrients within food production systems and producing animal and plant foods more efficiently will cut costs and increase desirable outputs.
Article
Environmental Sciences
Kaveh G. Siah, Steven S. Perakis, Julie C. Pett-Ridge, Gregory van der Heijden
Summary: Nutrient limitation of tree growth can intensify when nutrients are lost to forest harvest, creating challenges for forest growth and sustainability. Forest harvest accelerates nutrient loss by removing nutrient-containing biomass and by increasing nutrient leaching, shaping patterns of nutrient depletion that cause long-term shifts in nutrient limitation.
Article
Multidisciplinary Sciences
Marianne Acker, Shane L. Hogle, Paul M. Berube, Thomas Hackl, Allison Coe, Ramunas Stepanauskas, Sallie W. Chisholm, Daniel J. Repeta
Summary: This study reveals that a small fraction of microbial producers in the ocean sustain the presence of phosphonates and allocate a significant portion of their phosphorus quota for phosphonate production. The phosphonates may be associated with cell-surface glycoproteins, mediating ecological interactions between the cell and its surrounding environment.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Environmental Sciences
Junrui Cheng, Yuemin Gong, David Z. Zhu, Ming Xiao, Zhaozhao Zhang, Junpeng Bi, Kan Wang
Summary: The study found that the river network in the Yong River Basin has a significant phosphorus retention capacity and is currently in a phase of phosphorus accumulation. The results also indicate that variations in hydrological regimes, water surface area, unit area inputs of phosphorus, and concentrations of suspended sediments have a great influence on phosphorus retention.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Article
Engineering, Civil
Songjun Wu, Doerthe Tetzlaff, Tobias Goldhammer, Chris Soulsby
Summary: Climate change and riparian management are significant drivers of hydrological change, impacting nutrient fluxes in lowland streams. Long-term assessment in a mixed land use catchment in northern Germany revealed how climatic variability influences hydrological dynamics, with discharge and groundwater levels closely linked to changes in temperature and rainfall. The study also highlighted the role of beaver dams in moderating flow regimes and facilitating groundwater recharge, as well as the complex dynamics of nutrient concentrations and fluxes in stream water systems.
JOURNAL OF HYDROLOGY
(2021)
Article
Environmental Sciences
Derrick R. Vaughn, Anne M. Kellerman, Kimberly P. Wickland, Robert G. Striegl, David C. Podgorski, Jon R. Hawkings, Jaap H. Nienhuis, Mark M. Dornblaser, Edward G. Stets, Robert G. M. Spencer
Summary: Landcover changes have impacted the natural carbon cycle, with differences in dissolved organic carbon concentrations and molecular compositions in streams draining forest, agriculture, and urban landcovers. Forest and urban streams have higher DOC concentrations, while agricultural and urban streams show higher abundances of N-,S- heteroatomic formulae. The differences likely result from carbon sourcing, microbial processing, soil disturbance, and anthropogenic inputs.
Article
Environmental Sciences
Tristram D. L. Irvine-Fynn, Pete Bunting, Joseph M. Cook, Alun Hubbard, Nicholas E. Barrand, Edward Hanna, Andy J. Hardy, Andrew J. Hodson, Tom O. Holt, Matthias Huss, James B. McQuaid, Johan Nilsson, Kathrin Naegeli, Osian Roberts, Jonathan C. Ryan, Andrew J. Tedstone, Martyn Tranter, Christopher J. Williamson
Summary: The study reveals similarities in seasonal patterns of bare-ice reflectance across different datasets, but also unique short-term dynamics in reflectance distribution. It suggests that areal mean reflectance plays a key role in controlling local ablation rates, while the spatial distribution of specific ice types and impurities is of secondary importance. The findings recommend improving albedo parameterizations by assessing the representativeness of time-averaged reflectance data products and using temporally-resolved functions to describe impurity distribution variability at daily time-scales.
Article
Chemistry, Multidisciplinary
Alexander D. Beaton, Allison M. Schaap, Robin Pascal, Rudolf Hanz, Urska Martincic, Christopher L. Cardwell, Andrew Morris, Geraldine Clinton-Bailey, Kevin Saw, Susan E. Hartman, Matthew C. Mowlem
Summary: A new family of miniaturized lab-on-chip colorimetric analyzers has been developed for in situ nitrate and phosphate measurements in the ocean, suitable for depths up to >4800 m. The analyzers show comparable performance to laboratory-based analyses and offer a new low-cost, high-performance tool for measuring chemistry in hyperbaric environments.
Article
Geography, Physical
Horst Machguth, Andrew J. Tedstone, Enrico Mattea
Summary: The marginal areas of the Greenland ice sheet develop streams and lakes each summer, indicating the important role of surface runoff in the ice-sheet mass balance. This study maps the extent of surface runoff using MODIS data from 2000 to 2021 and finds an increasing trend in maximum slush limits until 2012. The data also suggest that the upward migration of surface runoff in 2012 stopped early due to thick ice layers near the surface.
JOURNAL OF GLACIOLOGY
(2023)
Letter
Geosciences, Multidisciplinary
N. Jullien, A. J. Tedstone, H. Machguth, N. B. Karlsson, V. Helm
Summary: We analyzed airborne accumulation radar data from 2002 to 2018 to investigate changes in the extent and thickness of ice slabs in Greenland. It was found that ice slabs several meters thick were already present before 2002. Between 2012 and 2018, the ice slabs expanded inland by 13,400-17,600 km(2), or 37%-44%. The study also demonstrated that the extremely warm summer of 2012 led to the formation of near-surface ice layers at higher elevations, enabling the development of ice slabs with only moderate melting in subsequent summers.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geography, Physical
Shunan Feng, Joseph Mitchell Cook, Alexandre Magno Anesio, Liane. G. G. Benning, Martyn Tranter
Summary: Albedo is an important factor affecting solar radiation absorption on ice surfaces. Satellite measurements show a general decrease in albedo on the Greenland ice sheet, particularly in the Dark Zone (albedo < 0.45). This study used a combination of Landsat 4-8 and Sentinel 2 imagery to derive the longest record of albedo variations in the Dark Zone from 1984 to 2020. By developing a sensor transformation method, the researchers obtained consistent and harmonized satellite imagery. The results indicate an expansion of the Dark Zone and a decrease in albedo over time.
JOURNAL OF GLACIOLOGY
(2023)
Article
Geosciences, Multidisciplinary
David M. Chandler, Alun Hubbard
Summary: Dramatic supraglacial lake drainage events in Greenland and Antarctica are caused by fast hydrofracture propagation, but this study presents a slower mode of hydrofracture where hairline fractures intersect supraglacial streams. They suggest that water supply and englacial refreezing are critical factors limiting penetration depth. The study proposes that stream-driven hydrofractures are widespread across Greenland and Antarctica's ablation zones, and have significant impacts on englacial thermal profiles and the vulnerability of ice sheets and shelves to dynamic instability.
Article
Geography, Physical
Laura Halbach, Lou-Anne Chevrollier, Joseph M. Cook, Ian T. Stevens, Martin Hansen, Alexandre M. Anesio, Liane G. Benning, Martyn Tranter
Summary: The surface of the Greenland Ice Sheet is darkening, accelerating its melt. The role of glacier ice algae in reducing surface albedo is acknowledged but poorly quantified, and the feedbacks between the algae and the weathering crust are not well understood. The letter summarises recent advances and identifies three key research priorities to better understand and forecast algal-driven melt.
ANNALS OF GLACIOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Ryan Venturelli, Brenna Boehman, Christina R. Davis, Jon E. Hawkings, Sarah D. Johnston, Chloe B. Gustafson, Alexander Michaud, Cyrille R. Mosbeux, Matthew J. Siegfried, Trista Vick-Majors, Valier Galy, Robert G. M. Spencer, Sophie C. Warny, Brent A. Christner, Helen M. Fricker, David Harwood, Amy C. Leventer, John E. Priscu, Brad Rosenheim, SALSA Sci Team
Summary: Through isotopic measurements of water and sediment taken from a subglacial lake in the southern Ross Sea of Antarctica, located 150 km inland from the modern grounding line and beneath over 1 km of ice, researchers have found that the grounding line of the Siple Coast of West Antarctica retreated more than 250 km inland around 6,300 years ago, before readvancing to its current position.
Article
Environmental Sciences
Caroline C. Clason, Giovanni Baccolo, Edyta Lokas, Philip N. Owens, Przemyslaw Wachniew, Geoff E. Millward, Alex Taylor, Will H. Blake, Dylan B. Beard, Ewa Poniecka, Nick Selmes, Elizabeth A. Bagshaw, Joseph Cook, Ralph Fyfe, Melanie Hay, Deborah Land, Nozomu Takeuchi, Massimiliano Nastasi, Monica Sisti, Francesca Pittino, Andrea Franzetti, Roberto Ambrosini, Biagio Di Mauro
Summary: The accumulation of FRNs in cryoconite on glaciers has been found to be highly efficient, with activity concentrations potentially up to thousands of times higher than the surrounding environment. This study highlights the need for further research on the fate of contaminants in glaciated catchments and their impacts on downstream water quality and ecosystem sustainability.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Plant Sciences
Marie Bolander Jensen, Laura Perini, Laura Halbach, Hans Jakobsen, Lumi Haraguchi, Sofia Ribeiro, Martyn Tranter, Liane Benning, Alexandre Anesio
Summary: Cultures of Ancylonema sp. were successfully established and maintained for up to 2 years by optimizing growth media and parameters. The genetic diversity of these cultures was found to be rich, and they were confirmed to belong to the same clade as A. nordenskioldii and A. alaskanum. Despite successful growth and long-term maintenance, laboratory settings can be further improved for optimal growth conditions.
Article
Ecology
Beatriz Gill-Olivas, Jon Telling, Mark Skidmore, Martyn Tranter
Summary: This study investigates the potential of subglacial erosion to generate H2O2 and release organic carbon and nutrients. The results show that erosion can provide previously unaccounted sources of bio-utilisable energy substrates and nutrients, playing an important role in subglacial microbial ecosystems.
Article
Ecology
Christopher M. Bellas, Karley Campbell, Martyn Tranter, Patricia Sanchez-Baracaldo
Summary: Sea ice habitats host abundant microalgae communities, which are highly productive in spring due to increased light availability. However, the metabolic pathways of the prokaryotic community relying on these microalgae for organic carbon remain poorly understood. In this study, metagenomic assembled genomes were generated from first-year sea ice in northwestern Hudson Bay during a diatom bloom, revealing that the prokaryotic community has the potential to degrade algal-derived compounds and oxidize sulfur. Additionally, anaerobic metabolisms such as dissimilatory nitrate reduction and denitrification were prevalent, suggesting metabolic adaptation to fluctuating oxygen levels during algal blooms in sea ice.
ISME COMMUNICATIONS
(2023)
Article
Microbiology
Ate H. Jaarsma, Katie Sipes, Athanasios Zervas, Francisco Campuzano Jimenez, Lea Ellegaard-Jensen, Mariane S. Thogersen, Peter Stougaard, Liane G. Benning, Martyn Tranter, Alexandre M. Anesio
Summary: The microbiome of Greenland Ice Sheet supraglacial habitats was investigated using a combination of culturing-dependent and -independent approaches. The study found that high-throughput sequencing provided insights into dominant community members, while isolates obtained through culturing did not represent these dominant taxa. The study also demonstrated the usefulness of metagenome SSU rRNA genes in reflecting overall community diversity.
FEMS MICROBIOLOGY ECOLOGY
(2023)
Article
Geography, Physical
Nicole Clerx, Horst Machguth, Andrew Tedstone, Nicolas Jullien, Nander Wever, Rolf Weingartner, Ole Roessler
Summary: The Greenland Ice Sheet is losing mass due to increasing runoff, with the location of the runoff limit playing a key role in the ice sheet's surface mass balance. Recent observations suggest that the rise in runoff area may be linked to an increasing amount of refreezing, promoting lateral runoff.
