Article
Environmental Sciences
Karista Hudelson, Derek C. G. Muir, Guenter Koeck, Xiaowa Wang, Jane L. Kirk, Igor Lehnherr
Summary: Lake Hazen, the largest lake north of the Arctic circle, is experiencing mercury pollution and climate change. The sensitive Arctic char inhabiting the lake has shown significant declines in mercury concentrations over the past 31 years, with increased rainfall and earlier freeze-up of lake ice being linked to increased age and length of the fish.
ENVIRONMENTAL POLLUTION
(2023)
Article
Engineering, Environmental
Ryan F. Lepak, Jacob M. Ogorek, Krista K. Bartz, Sarah E. Janssen, Michael T. Tate, Yin Runsheng, James P. Hurley, Daniel B. Young, Collin A. Eagles-Smith, David P. Krabbenhoft
Summary: This study assessed the importance of migrating oceanic salmon, volcanic activity, and atmospheric deposition to fish mercury burden by analyzing lake trout in 13 remote lakes in southwestern Alaska. The results showed that volcanic activity is a significant additional source of mercury in proximate lakes, while migratory salmon contribute little methylmercury directly to lake trout. The study also found niche partitioning and a complex suite of ecological interactions in lake trout populations.
ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS
(2022)
Article
Food Science & Technology
Iris Koch, Pranab Das, Bronte E. McPhedran, John M. Casselman, Kristy L. Moniz, Peter van Coeverden de Groot, James Qitsualik, Derek Muir, Stephan Schott, Virginia K. Walker
Summary: This study analyzed mercury levels in fish species from the Arctic waters, finding that most species had mercury levels below the guidelines for subsistence fisheries, but 70% of lake trout samples exceeded the safe threshold and 19% exceeded commercial sale levels. Therefore, it is recommended to establish consumption advisories for lake trout to protect human health.
Article
Environmental Sciences
Samantha Burke, Derek C. G. Muir, Jane Kirk, Benjamin D. Barst, Debbie Iqaluk, Xiaowa Wang, Mike Pope, Scott F. Lamoureux, Melissa J. Lafreniere
Summary: Climate-driven changes can have profound effects on contaminants like mercury in High Arctic lakes. This study found that permafrost degradation and increased turbidity in lakes can lead to changes in mercury concentrations and fish condition. While there was a significant decrease in mercury concentrations in one lake, there was a significant increase in another lake, likely due to the increase in turbidity and dietary changes.
ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY
(2023)
Article
Limnology
Ariana M. Chiapella, Collin A. Eagles-Smith, Angela L. Strecker
Summary: The study found that mercury concentrations in fish in mountain lakes are influenced by various factors such as catchment tree cover, lake benthic primary production, and fish diet. Tree cover and fish diet are the main factors contributing to variations in mercury concentrations in fish, with benthic feeding fish tending to have higher mercury concentrations.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Article
Biochemical Research Methods
Emmalyn J. Dupree, Zaen Manzoor, Shelby Alwine, Bernard S. Crimmins, Thomas M. Holsen, Costel C. Darie
Summary: This study established a lake trout protein database using proteomics approaches, providing insight into the protein profile of lake trout and enabling future research on this fish species.
Article
Evolutionary Biology
Yue Shi, Jared J. Homola, Peter T. Euclide, Daniel A. Isermann, David C. Caroffino, Megan McPhee, Wesley A. Larson
Summary: This study used a genomics approach to analyze the population structure and adaptive genetic diversity of lake whitefish populations in Lake Michigan. The results revealed different levels of population structure and multiple adaptive genomic islands, along with the identification of a potential inversion block.
EVOLUTIONARY APPLICATIONS
(2022)
Article
Multidisciplinary Sciences
Nicholas Kotowych, Aslak Smalas, Per-Arne Amundsen, Raul Primicerio
Summary: This research found that with increasing temperatures, the growth rate of Arctic charr in high latitude lakes is expected to increase. Climate warming will have important consequences for the life history and size-structured interactions of cold water fish species.
SCIENTIFIC REPORTS
(2023)
Article
Environmental Sciences
N. Mamoozadeh, C. Goldsworthy, L. Miller, N. Peterson, M. Meek
Summary: Knowledge of population-level relationships and life history forms is crucial for effective management plans for native trout, char, and salmon. However, in the Lake Superior basin, limited information on genetic connectivity and source-sink dynamics hampers the identification of restoration strategies for coaster brook trout. Through genetic analysis, we identified well-differentiated populations above natural waterfalls and three source populations for coaster brook trout. Our results highlight the importance of within-river populations and the need for instream restoration efforts to preserve this species.
JOURNAL OF GREAT LAKES RESEARCH
(2023)
Article
Engineering, Environmental
Susan S. A. Alkurdi, Raed A. Al-Juboori, Jochen Bundschuh, Les Bowtell, Alla Marchuk
Summary: The study showed that bone char is effective in removing inorganic arsenic from water, with the Sips model providing the best fit for As(III) experimental data and the Langmuir model suitable for As(V) data. At low concentrations, removal was due to intra-particle interactions and pore diffusion, while at higher concentrations, pore diffusion mechanism was ineffective.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Ecology
Erin F. Hamilton, Collin L. Juurakko, Katja Engel, Peter van C. de Groot, John M. Casselman, Charles W. Greer, Josh D. Neufeld, Virginia K. Walker
Summary: This study investigated the microbiome composition and condition of lake whitefish and cisco in high latitude regions. The results showed that the intestine microbiomes of lake whitefish were more susceptible to environmental stress and potential dysbiosis compared to cisco. Lake whitefish had lower condition in the ocean habitat, while cisco had similar condition across different seasonal habitats. These findings have important implications for fisheries and aquaculture management as well as the livelihood and economic interests of indigenous peoples.
Article
Environmental Sciences
Emilie Leclerc, Jason J. Venkiteswaran, Izabela Jasiak, James Telford, Mackenzie D. J. Schultz, Brent B. Wolfe, Roland I. Hall, Raoul-Marie Couture
Summary: Lake sediments are used as environmental archives to reconstruct past changes in contaminants deposition, however, the mobility of arsenic in sediments during early diagenesis may affect the reliability of As depth profiles. Results from the study suggest that lakes further than 50 km from mines act as sinks for arsenic, while lakes closer to the mines sustain present-day arsenic fluxes. The study also indicates that peaks in solid phase arsenic coincide with periods of high emissions from gold ore roasting activities.
ENVIRONMENTAL POLLUTION
(2021)
Article
Biochemistry & Molecular Biology
Ray Keren, Raphael Meheust, Joanne M. Santini, Alex Thomas, Jacob West-Roberts, Jillian F. Banfield, Lisa Alvarez-Cohen
Summary: This study investigated the genetic control of arsenic metabolic capacities based on microbial genomes and found distinct metabolic guilds. The microbiomes of humans exposed to arsenic showed a specific arsenic gene signature, and arsenic methylation plays an important role in soil and human microbiomes.
COMPUTATIONAL AND STRUCTURAL BIOTECHNOLOGY JOURNAL
(2022)
Article
Environmental Sciences
Xiaoming Zhou, Yijun Feng, Zonglin Gong
Summary: This study found associations between blood levels of heavy metal elements cadmium, lead, mercury, urinary total arsenic, dimethylarsinic acid and elevation of ALT in adults. The associations between blood lead and mercury with ALT elevation were only observed in women.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Environmental Sciences
Anh Quoc Hoang, Daichi Aono, Isao Watanabe, Narumi K. Tsugeki, Michinobu Kuwae, Shin Takahashi
Summary: The study determined the presence of 209 PCB congeners in a sediment core from Lake Biwa in Japan, dating back to 1930 to 2019. Concentrations of total PCBs peaked in the 1960s to 1970s, matching the Japanese PCB production and emission pattern. Specific congeners like CB-7,-11,-47/48/75,-51,-68, and-209 were found to have elevated concentrations with special historical profiles.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Fisheries
Peiwen Li, Peter van Coeverden de Groot, Rute B. G. Clemente-Carvalho, Stephen C. Lougheed
Summary: Contemporary intraspecific genetic variation in Arctic char populations reflects historical factors like population subdivision-expansion, with weak to moderate differentiation among sampling locales. Migration behavior may play a key role in shaping genetic population structure, with evidence of deeper genetic divisions and subgroups within populations. Additionally, SNPs potentially under divergent selection were identified, highlighting the importance of considering demographic modeling in conservation efforts.
CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES
(2021)
Article
Genetics & Heredity
Collin L. Juurakko, Melissa Bredow, Takato Nakayama, Hiroyuki Imai, Yukio Kawamura, George C. diCenzo, Matsuo Uemura, Virginia K. Walker
Summary: Research has shown that two days of cold acclimation are sufficient to protect the plasma membrane, leading to an initial increase in sugar levels and significant changes in the abundance of 154 proteins, while prolonged cold acclimation results in further increases in soluble sugars and abundance changes in over 680 proteins. The identified plasma membrane proteins play roles in low-temperature tolerance, metabolism, transport, pathogen defense, as well as various stress responses, suggesting crosstalk between different stress pathways.
G3-GENES GENOMES GENETICS
(2021)
Article
Food Science & Technology
Iris Koch, Pranab Das, Bronte E. McPhedran, John M. Casselman, Kristy L. Moniz, Peter van Coeverden de Groot, James Qitsualik, Derek Muir, Stephan Schott, Virginia K. Walker
Summary: This study analyzed mercury levels in fish species from the Arctic waters, finding that most species had mercury levels below the guidelines for subsistence fisheries, but 70% of lake trout samples exceeded the safe threshold and 19% exceeded commercial sale levels. Therefore, it is recommended to establish consumption advisories for lake trout to protect human health.
Article
Plant Sciences
Collin L. Juurakko, George C. diCenzo, Virginia K. Walker
Summary: Research found that the bacterial and fungal communities on leaves of plants that underwent cold acclimation significantly changed, with an increase in beneficial bacteria and decrease in ice-nucleating pathogens. This change may help plants combat cold and pathogens, enhancing their survival in freezing events.
Article
Plant Sciences
Collin L. Juurakko, George C. DiCenzo, Virginia K. Walker
Summary: Antifreeze proteins from Brachypodium have the ability to prevent freezing and pathogen-mediated ice nucleation. The encoded proteins can disrupt the ice nucleating arrays of bacterial ice nucleating proteins and inhibit the host immune response.
Article
Multidisciplinary Sciences
Jordan Forbes, Akalabya Bissoyi, Lukas Eickhoff, Naama Reicher, Thomas Hansen, Christopher G. Bon, Virginia K. Walker, Thomas Koop, Yinon Rudich, Ido Braslavsky, Peter L. Davies
Summary: Bacterial ice nucleation proteins (INPs) can cause frost damage to plants by nucleating ice formation at high sub-zero temperatures. Modeling and experimentation revealed that certain residues and structural continuity in a central segment of Pseudomonas borealis INP are critical for optimal ice nucleation activity. The C-terminal coils of INP also play a crucial role in its potency.
NATURE COMMUNICATIONS
(2022)
Article
Plant Sciences
Collin L. Juurakko, Melissa Bredow, George C. DiCenzo, Virginia K. Walker
Summary: A cluster of ice recrystallization inhibition (BdIRI) genes in Brachypodium distachyon, a model forage crop, encode antifreeze proteins that adsorb to ice crystals and inhibit their growth. Knockdown of these genes in transgenic plants resulted in reduced antifreeze activity and increased sensitivity to freezing and pathogen infection, without apparent developmental defects. These findings demonstrate the potential of using these proteins in biotechnological applications for cryopreservation and enhancing freeze and pathogen tolerance in crops.
Article
Biology
Heather E. Tomalty, Laurie A. Graham, Virginia K. Walker, Peter L. Davies
Summary: Antifreeze proteins (AFPs) prevent freezing and allow cells and organs to be stored at subzero temperatures. However, storing kidney cells at -6°C with the addition of AFPs does not increase storage times.
Article
Fisheries
Erin F. F. Hamilton, Collin L. L. Juurakko, Katja Engel, Josh D. D. Neufeld, John M. M. Casselman, Charles W. W. Greer, Virginia K. K. Walker
Summary: In the region of King William Island, Nunavut, diadromous fish in different seasonal habitats exhibit variations in their skin microbiota composition, indicating the influences of host genome and physiology. The findings challenge the assumption that skin communities mainly reflect water microbiota. These results have important implications for understanding the effect of environmental changes on fish populations in the high Arctic and suggest the use of skin microbiomes as a supplementary tool for monitoring sustainable Indigenous salmonid harvest.
Article
Environmental Sciences
Michelle M. McKnight, Paul Grogan, Virginia K. Walker
Summary: Recent climate warming in the Arctic is increasing microbial decomposition of soil organic matter, potentially releasing significant greenhouse gases into the atmosphere globally. Results showed that while climate warming may enhance soil microbial activity rates, it does not significantly alter the structure of bacterial or fungal communities. Increases in relative abundance of ectomycorrhizal fungal species Thelephora were observed in plots with phosphate and nitrogen + phosphate amendments, suggesting potential promotion of shrub competitiveness in Arctic vegetation greening scenarios.
ARCTIC ANTARCTIC AND ALPINE RESEARCH
(2021)