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Evolution in eruptive style of the 2018 eruption of Veniaminof volcano, Alaska, reflected in groundmass textures and remote sensing
Matthew W. Loewen, Hannah R. Dietterich, Nathan Graham, Pavel Izbekof
2021, Bulletin of Volcanology (83)
Variable eruptive style and explosivity is common in basaltic to basaltic andesite volcanoes but can have uncertain origins. Veniaminof volcano in the Alaska-Aleutian arc is a frequently active open-vent center, regularly producing Strombolian eruptions and small lava flows from an intracaldera cone within an intracaldera ice...
Active virus-host interactions at sub-freezing temperatures in Arctic peat soil
Gareth Trubl, Jeffrey A Kimbrel, Jose Liquet-Gonzalez, Erin E. Nuccio, Peter K. Weber, Jennifer Pett-Ridge, Janet K. Jansson, Mark Waldrop, Steve Blazewicz
2021, Microbiome (9)
BackgroundWinter carbon loss in northern ecosystems is estimated to be greater than the average growing season carbon uptake and is primarily driven by microbial decomposers. Viruses modulate microbial carbon cycling via induced mortality and metabolic controls, but it is unknown whether viruses are active under winter conditions (anoxic and...
Influence of permafrost type and site history on losses of permafrost carbon after thaw
Kristen L. Manies, Miriam C. Jones, Mark Waldrop, Mary-Catherine Leewis, Christopher C. Fuller, Robert S. Cornman, Kristen Hoefke
2021, Journal of Geophysical Research-Biogeosciences (126)
We quantified permafrost peat plateau and post-thaw carbon (C) stocks across a chronosequence in Interior Alaska to evaluate the amount of C lost with thaw. Macrofossil reconstructions revealed three stratigraphic layers of peat: (1) a base layer of fen/marsh peat, (2) peat from a forested peat plateau...
Assessment of variation in the detection and prevalence of blood parasites among sympatrically breeding geese in western Alaska, USA
Raymond M. Buchheit, Joel Schmutz, John A. Reed, Brian D. Uher-Koch, Andrew M. Ramey
2021, Journal of Wildlife Diseases (57) 799-807
Haemosporidian parasites may impact avian health and are subject to shifts in distribution and abundance with changing ecologic conditions. Therefore, understanding variation in parasite prevalence is important for evaluating biologically meaningful changes in infection patterns and associated population level impacts. Previous research in western Alaska, US, indicated a possible increase...
Acute oral toxicity and tissue residues of saxitoxin in the mallard (Anas platyrhynchos)
Robert J. Dusek, Matthew M. Smith, Caroline R. Van Hemert, Valerie I. Shearn-Bochsler, Sherwood Hall, Clark D. Ridge, Ransome Hardison, Robert Kaler, Barbara Bodenstein, Erik K. Hofmeister, Jeffrey S. Hall
2021, Harmful Algae (109)
Since 2014, widespread, annual mortality events involving multiple species of seabirds have occurred in the Gulf of Alaska, Bering Sea, and Chukchi Sea. Among these die-offs, emaciation was a common finding with starvation often identified as the cause of death. However, saxitoxin...
The climate envelope of Alaska’s northern treelines: Implications for controlling factors and future treeline advance
Colin T. Maher, Roman J. Dial, Neal J Pastick, Rebecca E. Hewitt, M. Torre Jorgenson, Patrick F. Sullivan
2021, Ecography (44) 1710-1722
Understanding the key mechanisms that control northern treelines is important to accurately predict biome shifts and terrestrial feedbacks to climate. At a global scale, it has long been observed that elevational and latitudinal treelines occur at similar mean growing season air temperature (GSAT) isotherms, inspiring the growth limitation hypothesis (GLH)...
Iñupiaq knowledge of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska
Karyn D. Rode, Hannah Voorhees, Henry P. Huntington, George M. Durner
2021, Arctic (74) 239-257
Successful wildlife management depends upon coordination and consultation with local communities. However, much of the research used to inform management is often derived solely from data collected directly from wildlife. Indigenous people living in the Arctic have a close connection to their environment, which provides unique opportunities to observe...
Fire and forests in the 21st century: Managing resilience under changing climates and fire regimes in USA forests
James M. Vose, David L. Peterson, Christopher J. Fettig, Jessica E. Halofsky, J. Kevin Hiers, Robert E. Keane, Rachel A. Loehman, Michael C. Stambaugh
2021, Book chapter, Fire ecology and management: Past, present, and future of US forested ecosystems
Higher temperatures, lower snowpacks, drought, and extended dry periods have contributed to increased wildfire activity in recent decades. Climate change is expected to increase the frequency of large fires, the cumulative area burned, and fire suppression costs and risks in many areas of the USA. Fire regimes are likely to...
DAS 3DVSP survey at Stratigraphic Test Well (Hydrate-01)
Akira Fujimoto, Teck Kean Lim, Machiko Tamaki, Kyojiro Kawaguchi, Toshiaki Kobayashi, Seth S. Haines, Timothy Collett, Ray Boswell
2021, Conference Paper, Proceedings of the 14th SEGJ International Symposium
This proceeding outlines the acquisition, processing, and fault interpretation of the largest known onshore distributed acoustic sensing (DAS) 3D vertical seismic profile (VSP) survey. This survey was carried out to detect the distribution of faults near the gas hydrate research well (Stratigraphic Test Well: Hydrate-01) on the North Slope of...
Demographic risk assessment for a harvested species threatened by climate change: Polar bears in the Chukchi Sea
Eric V. Regehr, Michael C. Runge, Andrew L. Von Duyke, Ryan R. Wilson, Lori Polasek, Karyn D. Rode, Nathan J. Hostetter, Sarah J. Converse
2021, Ecological Applications (31)
Climate change threatens global biodiversity. Many species vulnerable to climate change are important to humans for nutritional, cultural, and economic reasons. Polar bears Ursus maritimus are threatened by sea-ice loss and represent a subsistence resource for Indigenous people. We applied a novel population modeling-management framework that is based on species life history...
Multidisciplinary constraints on magma compressibility, the pre-eruptive exsolved volatile fraction, and the H2O/CO2 molar ratio for the 2006 Augustine eruption, Alaska
Valerie K. Wasser, Taryn M. Lopez, Kyle R. Anderson, Pavel E. Izbekov, Jeffrey T. Freymueller
2021, Geochemistry, Geophysics, Geosystems (G-Cubed) (22) 1-24
Geodetically modeled reservoir volume changes during volcanic eruptions are commonly much smaller than the observed eruptive volumes. This discrepancy is thought to be partially due to the compressibility of magma, which is largely controlled by the presence of exsolved volatiles. The 2006 eruption of Augustine Volcano, Alaska, produced an eruptive...
Satellites for long-term monitoring of inland U.S. lakes: The MERIS time series and application for chlorophyll-a
Bridget Seegers, P. Jeremy Werdell, Ryan Vandermeulen, Wilson Salls, Richard Stumpf, Blake Schaeffer, Tommy Owens, Sean Bailey, Joel Scott, Keith A. Loftin
2021, Remote Sensing of the Environment (266)
Lakes and other surface fresh waterbodies provide drinking water, recreational and economic opportunities, food, and other critical support for humans, aquatic life, and ecosystem health. Lakes are also productive ecosystems that provide habitats and influence global cycles. Chlorophyll concentration provides a common metric of water quality, and is frequently used...
Origin of unconsolidated Quaternary deposits at Harriet Point near Redoubt Volcano, Alaska
Christopher F. Waythomas
2021, Scientific Investigations Report 2021-5071
Unconsolidated boulder-rich diamicton units exposed in sea cliffs at Harriet Point southeast of Redoubt Volcano were evaluated to better understand their provenance relative to the late Quaternary eruptive history of the volcano. A previous study concluded that deposits at Harriet Point were emplaced by a large volcanic landslide originating on...
Survival and abundance of polar bears in Alaska’s Beaufort Sea, 2001–2016
Jeffrey F. Bromaghin, David C. Douglas, George M. Durner, Kristin S. Simac, Todd C. Atwood
2021, Ecology and Evolution (11) 14250-14267
The Arctic Ocean is undergoing rapid transformation toward a seasonally ice-free ecosystem. As ice-adapted apex predators, polar bears (Ursus maritimus) are challenged to cope with ongoing habitat degradation and changes in their prey base driven by food-web response to climate warming. Knowledge of polar bear response to environmental change is...
Impacts of climate changes and amplified natural disturbance on global ecosystems
Rachel A. Loehman, Megan Friggens, Rosemary L. Sherriff, Alisa R. Keyser, Karin L. Riley
2021, Book chapter, Routledge handbook of landscape ecology
Natural disturbances maintain biological diversity and landscape heterogeneity and initiate ecosystem renewal and reorganization. However, the severity, frequency, and extent of many disturbances have increased substantially in recent decades as the result of anthropogenic climate change. Disturbances can be discrete, short-duration events, such as wildfires or hurricanes, or can exert...
Growth of greater white-fronted goose goslings relates to population dynamics at multiple scales
Thomas F Fondell, Brandt W. Meixell, Paul L. Flint
2021, Journal of Wildlife Management (85) 1591-1600
The abundance of greater white-fronted geese (Anser albifrons frontalis) on the Arctic Coastal Plain (ACP) of northern Alaska, USA, has more than tripled since the late 1990s; however, recent rate of annual population growth has declined as population size increased, which may indicate white-fronted geese on the ACP are approaching...
Early Pleistocene climate-induced erosion of the Alaska Range formed the Nenana Gravel
Rachel Sortor, Brent Goehring, Sean Bemis, Chester A. Ruleman, Marc Caffee, Dylan Ward
2021, Geology (49) 1473-1477
The Pliocene-Pleistocene transition resulted in extensive global cooling and glaciation, but isolating this climate signal within erosion and exhumation responses in tectonically active regimes can be difficult. The Nenana Gravel is a foreland basin deposit in the northern foothills of the Alaska Range (USA) that...
Surface energy balance of sub-Arctic roads with varying snow regimes and properties in permafrost regions
Lin Chen, Clifford I. Voss, Daniel Fortier, Jeffrey M. McKenzie
2021, Permafrost and Periglacial Processes (32) 681-701
Surface energy balance (SEB) strongly influences the thermal state of permafrost, cryohydrological processes, and infrastructure stability. Road construction and snow accumulation affect the energy balance of underlying permafrost. Herein, we use an experimental road section of the Alaska Highway to develop a SEB model to quantify the surface energy components...
Negligible evidence for detrimental effects of Leucocytozoon infections among Emperor Geese (Anser canagicus) breeding on the Yukon-Kuskokwim Delta, Alaska
Andrew M. Ramey, Raymond Bucheit, Brian D. Uher-Koch, John Reed, M. Andreina Pacheco, Ananias Escalante, Joel Schmutz
2021, International Journal for Parasitology: Parasites and Wildlife (16) 103-112
Emperor Geese (Anser canagicus) are iconic waterfowl endemic to Alaska and adjacent areas of northeastern Russia that are considered to be near threatened by the International Union for Conservation. This species has been identified as harboring diverse viruses and parasites which have, at times, been associated with disease in other avian taxa....
Assessment of barrier island morphological change in northern Alaska
Anna I. Hamilton, Ann E. Gibbs, Li H. Erikson, Anita C. Engelstad
2021, Open-File Report 2021-1074
Arctic barriers islands are highly dynamic features influenced by a variety of oceanographic, geologic, and environmental factors. Many Alaskan barrier islands and spits serve as habitat and protection for native species, as well as shelter the coast from waves and storms that cause flooding and degradation of coastal villages. This...
A decade of Indigenous knowledge research in the Yukon River basin: Reflection on “Indigenous observations of change in the lower Yukon River basin, Alaska”
Nicole M. Herman-Mercer
2021, Human Organization (80) 234-245
Herman-Mercer reflects on her first article" Indigenous Observations of Change in the Lower Yukon River Basin, Alaska." The observations and knowledge presented in this study have become part of an ever-growing catalog of studies representing, and part of a chorus of Indigenous communities across the Arctic and Subarctic conveying, the...
Assessing potential stock structure of adult Coho Salmon in a small Alaska watershed: Quantifying run timing, spawning locations, and holding areas with radiotelemetry
M. E. Stratton, H. Finkle, Jeffrey A. Falke, P. A. H. Westley
2021, North American Journal of Fisheries Management (41) 1423-1435
Run timing and spatial locations of spawning habitats are often used to identify stocks for conservation planning or management of salmonid fishes. Although complex stock structure is most common within large watersheds with diverse habitats, even small drainages can produce multiple co-occurring spatially or temporally isolated populations or “stocks.” This...
Dynamic selection for forage quality and quantity in response to phenology and insects in an Arctic ungulate
Heather E. Johnson, Trevor Golden, Layne G. Adams, David Gustine, Elizabeth A. Lenart, Perry Barboza
2021, Ecology and Evolution (11) 11664-11688
Spatiotemporal variation in forage is a primary driver of ungulate behavior, yet little is known about the nutritional components they select, and how selection varies across the growing season with changes in forage quality and quantity. We addressed these uncertainties in barren-ground caribou (Rangifer tarandus), which...
Storm-scale and seasonal dynamics of carbon export from a nested subarctic watershed underlain by permafrost
Joshua C. Koch, Mark Dornblaser, Rob Striegl
2021, Journal of Geophysical Research Biogeosciences (126)
Subarctic catchments underlain by permafrost sequester a major stock of frozen organic carbon (C), which may be mobilized as the Arctic warms. Warming can impact C export from thawing soils by altering the depth and timing of runoff related to changing storm and fire regimes and altered soil thaw depths....
Energetic and health effects of protein overconsumption constrain dietary adaptation in an apex predator
Karyn D. Rode, Charles T. Robbins, Craig A. Stricker, Brian D. Taras, Troy N Tollefson
2021, Scientific Reports (11)
Studies of predator feeding ecology commonly focus on energy intake. However, captive predators have been documented to selectively feed to optimize macronutrient intake. As many apex predators experience environmental changes that affect prey availability, limitations on selective feeding can affect energetics and health. We estimated the...