• An evaluation of GPR techniques for analyzing the safety of Interior Alaskan ice roads under varying river ice and environmental conditions

      Richards, Elizabeth M.; Stuefer, Svetlana; Maio, Chris; Belz, Nathan; Daanen, Ronald (2021-05)
      Ice roads and bridges are necessary routes to transport heavy equipment, supplies and food in the winter months to and from isolated cold region communities off the road system. Ice roads allow for community members to avoid the high costs of air shipments and obtain equipment and vehicles that would otherwise not be available. These ice roads traverse frozen bodies of water (e.g., rivers, estuaries, and lakes), and require extreme safety when driving over. To achieve this, calculations are frequently completed to determine the maximum acceptable loading on the ice cover. River ice tends to have increased safety concerns and uncertainty for travel that stem from warmer air temperatures and other factors such as precipitation, snow drifting, and ice cover forming differently each year. The necessity of obtaining time intensive ice thickness measurements by hand puts the responsible personnel at considerable risk of injury or fatality. Ground penetrating radar (GPR), which has gained much popularity in the last few decades, is a quicker and more effective non-invasive method for measuring ice thickness and other properties. The GPR system was tested for its accuracy in measuring ice thickness on common transportation routes on the Yukon River and the Tanana River. Identification of varying ice type layers in river ice cover using GPR was also attempted. While layers could not be identified using the 450 MHz and 750 MHz central frequency antennas, an accuracy analysis of GPR ice thickness measurements under various environmental conditions was completed. This analysis contributes to a comprehensive understanding of the safety of ice roads for community members in remote northern villages and provides the basis for further research on identifying layers in river ice cover.
    • Even in Arcadia: stories

      Wood, Rebecca N.; Farmer, Daryl; Johnson, Sara; Schell, Jennifer (2021-05)
      Even in Arcadia: Stories is a short story collection that follows adolescent and young adult women as they navigate growing up and growing out of the spaces they inhabit. Set in the American southwest, specifically unnamed suburban and rural cities of Arizona, the collection challenges the culturally popular narratives that surround the West-- the idealized cowboy, rugged individualism, and conquest of nature. Drawing on long-standing myths, serialized TV shows, and classic literature, the collection asks the reader to evaluate the stories they consume and are willing to take as truth. The stories range from realistic to speculative, employing horror and surrealistic elements as they descend into a sort of hellscape that draws on natural elements of desert landscapes juxtaposed against urban spaces. The collection focuses on gender, adolescence, and trauma set in the aftermath of the 2008 recession and the decline of small-town America from the perspective of youth.
    • Experimental investigation of polymer induced fouling of heater tubes in the first-ever polymer flood pilot on Alaska North Slope

      Dhaliwal, Anshul; Dandekar, Abhijit; Zhang, Yin; Goering, Douglas J. (2021-08)
      Mineral fouling in heat exchangers has been extensively investigated by researchers in recent times. The oil and gas industry has a long history of fouling issues in production systems as a result of produced fluids treatment. Due to decline in production rates in oilfields new technologies are being developed and field tested in pilots. Polymer flooding is one such technology that involves addition of polymers to injection fluids to enhance oil production. A polymer flood pilot has been set up in the Schrader Bluff viscous oil reservoir at Milne Point field on the Alaska North Slope (ANS). The results from the pilot are encouraging, however a major concern of the operator is the influence of polymer on the production system after breakthrough, especially the fouling in heat exchangers. This study investigates the propensity of polymer fouling on the heater tubes as a function of different variables, with the ultimate goal of determining safe and efficient operating conditions. This work applies a multi-experimental approach to study the severity of polymer-induced fouling in both dynamic and static states of produced fluids as well as studying the stability of polymer solutions at different temperatures. A unique experimental setup was designed and developed in-house to simulate the fouling process on the heating tube. The influence of heating tube skin temperature, tube material, and polymer concentration on fouling tendency was investigated. Each test was run five times with the same tube, and in each run, the freshly prepared synthetic brine and polymer solution was heated from 77°F to 122°F to mimic field-operating conditions. The heating time and fouling amount were recorded for each run. Dynamic Scale Loop (DSL) tests were conducted to study fouling due to polymer at different temperatures (165°F to 350°F) in a dynamic state of fluid flow where the fluids mimic the residence time of fluids in the heat exchanger on the field pilot. Cloud point measurement has also been conducted to find the critical temperature at which the polymer in solution becomes unstable and precipitates out. The morphology and composition of the deposit samples were analyzed by environmental scanning electron microscopy (ESEM) and X-ray diffraction (XRD), respectively. It was found that the presence of polymer in produced fluids would aggravate the fouling issues on both carbon steel and stainless-steel surfaces at all tested skin temperatures. Only higher skin temperatures of 250°F and 350°F could cause polymer-induced fouling issues on the copper tube surface, and the fouling tendency increased with polymer concentration. At the lower skin temperatures of 165°F, no polymer-induced fouling was identified on the copper tube. A critical temperature that is related to the cloud point of the polymer solution was believed to exist, below which polymer-induced fouling would not occur, and only mineral scale was deposited but above which the polymer would aggravate the fouling issue. The cloud point of the tested polymer solution was determined to be between 220°F and 230°F. In the DSL tests it was found that at higher skin temperatures of 250°F and 350°F tube blocking was observed in the DSL tests whereas the tests at 165°F and 200°F did not show any tube blocking in the same time period. These experiments also manifested the influence of cloud point of the solution as deposit rate increased significantly in both carbon steel and stainless-steel tubes when the skin temperature was higher than the solution cloud point. The results of this study have provided guidance to the operator for the field-operations.
    • Experimental investigation of the role of different clays in low salinity waterflooding

      Ivuawuogu, Henry; Zhang, Yin; Dandekar, Abhijit; Khataniar, Santanu; Awoleke, Obadare (2020-08)
      Various studies have demonstrated that Low Salinity Water Flooding (LSWF) can enhance oil recovery effectively, and its typical recovery mechanisms have been recognized. However, there is still a significant debate on the functions of clay during LSWF. This study investigates the impact of different clays, including montmorillonite, illite, and kaolinite, on the performance of LSWF. The zeta potentials of sand, montmorillonite, illite, and kaolinite in the presence of high salinity water (HSW) and low salinity water (LSW) were first examined. Then, the swelling factors of the three clay minerals in the HSW and LSW were measured in succession to determine their swelling characteristics. Subsequently, coreflooding experiments were conducted using one clay-free sand pack column and five sand pack columns respectively containing 10 wt% of montmorillonite, 10 wt% of illite, 10 wt% of kaolinite, compound clays (5 wt% of montmorillonite + 2.5 wt% of illite + 2.5 wt% of kaolinite), and 5 wt% of montmorillonite and the cumulative oil production and pressure drops were recorded. A produced crude oil sample with the American Petroleum Institute (API) gravity of 34° and viscosity of 14 cP (60°F) was used in the experiments. The total dissolved solids (TDS) of the HSW and LSW are 27,501 mg/L, and 2,485 mg/L respectively. It has been found that LSW could generate more negative zeta potential values for sand, montmorillonite, illite, and kaolinite, which made them more water-wet and thus favor oil recovery. Montmorillonite obviously swelled in HSW, and it could further swell significantly by contacting LSW. Although illite showed some swelling in HSW, LSW could not further expand it. Kaolinite did not swell in both HSW and LSW. The results from six coreflooding experiments showed that after high salinity waterflooding, the subsequent LSWF could generally further improve the oil recovery. The sand pack columns containing montmorillonite showed higher incremental oil recovery during LSWF (17.42% from sand pack column with 10 wt% of montmorillonite, 10.27% from sand pack column with compound clay, and 8.90% from sand pack column with 5 wt% of montmorillonite). Also, LSWF could improve oil recovery for the clay-free sand pack column, the sand pack column with kaolinite, and the sand pack column with illite by 0.73%, 0.83%, and 1.03%, respectively. Therefore, clay minerals would play an important role in determining oil recovery performance in LSWF, and the more swelling there is in clay in LSW, the more favorable it is in LSWF. This study proved that both clay swelling and wettability alteration could attribute to the improved oil recovery by LSWF.
    • Exploring infrasound wavefields to characterize volcanic eruptions

      Iezzi, Alexandra M.; Fee, David; Tape, Carl; West, Michael; Izbekov, Pavel; Haney, Matthew (2020-08)
      Infrasound has become an increasingly popular way to monitor and characterize volcanic eruptions, especially when combined with multidisciplinary observations. Regardless of how close the infrasound instruments are to the eruption, the effects from propagation must be considered prior to characterizing and quantifying the source. In this dissertation, we focus on modeling the effects of the atmosphere and topography on the recorded infrasound waveforms in order to better interpret the acoustic source and its implications on the volcanic eruption as a whole. Alaska has 54 historically active volcanoes, one third of which have no local monitoring equipment. Therefore, remote sensing (including that of infrasound arrays) is relied upon for the detection, location, and characterization of volcanic eruptions. At long ranges, the wind and temperature structure of the atmosphere affects infrasound propagation, however, changes in these conditions are variable both in time and space. We apply an atmospheric reconstruction model to characterize the atmosphere and use infrasound propagation modeling techniques for a few recent eruptions in Alaska. We couple these atmospheric propagation results with array processing techniques to provide insight into detection capability and eruption dynamics for both transient and long-duration eruptions in Alaska. Furthermore, we explore the future implementation of this long-range infrasound propagation modeling as an additional monitoring tool for volcano observatories in real time. The quantication of volcanic emissions, including volume flow rate and erupted mass, is possible through acoustic waveform inversion techniques that account for the effects of propagation over topography. Previous volcanic studies have generally assumed a simple acoustic source (monopole), however, more complex source reconstructions can be estimated using a combination of monopole and dipole sources (multipole). We deployed an acoustic network around Yasur volcano, Vanuatu, which has eruptions every 1-4 minutes, including acoustic sensors along a tethered aerostat, allowing us to better constrain the acoustic source in three dimensions. We find that the monopole source is a good approximation when topography is accounted for, but that directionality cannot be fully discounted. Inversions for the dipole components produce estimates consistent with observed ballistic directionality, though these inversions are somewhat unstable given the station conguration. Future work to explore acoustic waveform inversion stability, uncertainty, and robustness should be performed in order to better estimate and quantify the explosion source. Volcanic explosions can produce large, ash-rich plumes that pose great hazard to aviation. We use a single co-located seismic and infrasound sensor pair to characterize 21 explosions at Mount Cleveland, Alaska over a four-year study period. While the seismic explosion signals were similar, the acoustic signals varied between explosions, with some explosions exhibiting single main compressional phase while other explosions had multiple compressions in a row. A notable observation is that the seismo-acoustic time lag varied between explosions, implying a change in the path between the source and receiver. We explore the influence of atmospheric effects, nonlinear propagation, and source depth within the conduit on this variable seismo-acoustic time lag. While changes in the atmospheric conditions can explain some of the observed variation, substantial residual time lags remain for many explosions. Additionally, nonlinear propagation does not result in a measurable difference for the acoustic onset. Therefore, using methods such as seismic particle motion analysis and cross correlation of waveforms between events, we conclude that varying source depth within the conduit likely plays a key role in the observed variation in the seismo-acoustic time lags at Mount Cleveland.
    • Exploring the use of machine learning for daily fire growth prediction in Alaska

      White, James; Walsh, John; Thoman, Richard; Bhatt, Uma (2021-05)
      Wildfire is a natural but often hazardous part of the Alaskan ecosystems. Physically based wildfire models range from simple relationships used for rapid, in-situ fire behavior analysis to complex weather models used for prediction over several days and weeks. Physical models in Alaska, however, often struggle to integrate weather forecast information to make predictions beyond just a few days. The random forest model explored here is able to leverage an array of variables to identify days of enhanced and reduced satellite fire detections. Peaks and lulls in activity are accurately identified, though exact magnitudes are often incorrect, especially when wildfire suppression efforts occurred. This study emphasizes the use of reanalysis weather variables in addition to antecedent fire activity, highlighting the usefulness of variables like vapor pressure deficit for use in quantitative prediction. By applying weather forecast data, the model generated simulated wildfire forecasts. These forecasts show some success at identifying peaks and lulls in fire activity. Effective lead time varied widely ranging between 1 and 10 days, mostly dependent on the weather model performance. By providing specific timing and using real ensemble forecasts for medium term prediction, a model likes this fills a potential open niche in fire predictive services. Machine learning may be especially useful for its relative efficiency and ease of automation.
    • Fate and effects of commercial crude oil bioremediation products in Arctic seawater

      Gofstein, Taylor R.; Leigh, Mary Beth; Simpson, William; Guerard, Jennifer; Collins, R. Eric (2020-08)
      With increased oil exploration, development, and transport in the Arctic in recent years, the potential for disastrous oil spills is imminent. Biodegradation, the consumption of contaminants by indigenous microorganisms capable of using them as an energy source, can be enhanced using bioremediation treatments and may be a viable spill remediation method when traditional physical recovery techniques are not. The EPA National Contingency Plan (NCP) product schedule lists oil spill response treatments that can be used in the event of a spill, many of which can stimulate intrinsic biodegradation. However, there is often little to no experimental data demonstrating the effectiveness of these products in aiding the remediation of a spill. Here we investigate the effects of the currently listed NCP products Corexit 9500 and Oil Spill Eater II (OSEII) on crude oil biodegradation in Arctic seawater and the associated shifts in the microbial community using mesocosm incubations. Despite conflicting reports in the literature, Corexit 9500 showed no inhibitory effects on the biodegradation of crude oil. When oil and Corexit were co-present, chemical and microbial data revealed a sequential degradation beginning with the non-ionic surfactant components of Corexit (Span 80, Tween 80, Tween 85), followed by the degradation of the labile alkane oil components, with the degradation of other Corexit components such as dioctyl sodium sulfosuccinate (DOSS) and dipropylene glycol n-butyl ether (DGBE) less clear. 16S rRNA gene sequencing revealed that oil and Corexit stimulate different microbial communities but some taxa are stimulated by either (Oleispira, Pseudofulvibacter, Roseobacter), suggesting that these organisms may be capable of degrading both. Further analysis with metatranscriptomic sequencing showed increased gene expression in the presence of Corexit, even when co-present with oil, suggesting that Corexit may enhance the metabolic activity of oil degraders. Increased expression of β-oxidation pathway genes (fadE, fadA, fadB) in the presence of Corexit coincided with the chemical loss of Corexit components. Based on these findings and the abundance of ester groups in the chemical structures of Corexit 9500 surfactant components, we propose a biodegradation pathway that involves the transformation of ester groups into fatty acids either through biotic lipase enzymes or abiotic hydrolysis, before funneling into the β-oxidation fatty acid degradation pathway. Taxonomic origins for these transcripts showed a diverse number of genera expressing these genes, which along with its lability may serve to explain the number of taxa observed to respond to Corexit both here and in the literature. Characterization of the contents of OSEII revealed the presence of sugars, surfactants, nutrients, phytochemicals, amylase, protease, and the non-hydrocarbonoclastic non-viable microorganisms Lactobacillus and Saccharomyces. Incubation experiments targeting the efficacy of OSEII showed a slight enhancement of n-alkane loss at 30 days, suggesting that it may have utility in longer term use following a post-spill nutrient depletion. However, the nutrient contents of OSEII were up to 32-fold times higher for ammonia and 100,000-fold times higher for iron than in ambient Arctic seawater, which although are limiting nutrients in seawater, may also cause more harmful ecological effects following a spill by inducing phytoplankton blooms. Based on these findings, the non-ionic surfactants of Corexit 9500 appear to be easily degraded through the proposed β-oxidation fatty acid pathway. Future NCP dispersants should target these labile ester chemical moieties while also being effective at dispersion. It is imperative for NCP products to undergo more rigorous third-party experiments to demonstrate their suitability, effectiveness, toxicity, and unintended side effects that may occur in situ before an oil spill occurs. Doing so will allow decision-makers to have comprehensive information to aid in selection of appropriate oil spill response techniques.
    • Feasibility of multiple camera large-scale particle image velocimetry techniques for rivers in Alaska

      LaMesjerant, Eric N.; Toniolo, Horacio; Barnes, David; Shur, Yuri (2020-12)
      Alaska is characterized by sparse hydrologic data. Non-intrusive gauging is one method of increasing the data available but is limited in its current application. This study seeks to assess the feasibility of using commercially available software and multiple cameras to diversify the conditions for which large-scale particle image velocimetry may be applied. Using available software and the deployment of multiple cameras, stereoscopically determined discharge is compared with discharge determined using an acoustic Doppler current profiler and accepted single camera practices currently in use with large-scale particle image velocimetry. The results indicate that the use of commercial software and multiple cameras is feasible, with additional work, and that there is a statistically significant relationship between the velocity index (alpha) and aspect ratio (B/H, width divided by average depth). The velocity index-aspect ratio data indicate that the velocity index is a result of the environmental and geometric conditions for a given cross section and that an empirical relationship could be established.
    • Genomic signatures of optimal growth temperature in the family Colwelliaceae

      Gentilhomme, Anais; Collins, R. Eric; Hennon, Gwenn M.M.; Leigh, Mary-Beth; Drown, Devin (2020-12)
      The temperature range supporting growth defines a complex physiological phenotype that depends on interactions between an organism's genome and its environment. Its implications are widespread since small changes in optimal growth temperature (OGT) can alter an organism's ability to inhabit an ecological niche. Thus, organisms with extreme thermal growth traits (e.g., psychrophilic, with OGT < 15℃, or thermophilic, with OGT 60 -80℃) may be useful for identifying promising targets when searching for life on other planets, as well as predicting population dynamics in a warming Arctic. We performed comparative genomic analyses of bacteria newly isolated from Arctic sea ice that were affiliated with Colwelliaceae, a family of Gammaproteobacteria that contains many psychrophilic strains, to identify genomic factors that might be used to predict OGT. A phylogenomic analysis of 67 public and 39 newly-sequenced strains, was used to construct an updated phylogenetic tree of Colwelliaceae, of which at least two genera were well represented. To augment the previously reported OGTs of 26 strains, we measured growth rates at −1, 4, 11, and 17 ℃ to determine the OGTs of these 39 new strains of Colwelliaceae. We found that growth rates among all isolates were comparable at −1℃, but varied widely above 10 ℃, indicating higher variability in the ability to tolerate warmer temperatures. To analyze the phenotypic differences on a genomic level, we examined indices of amino acid substitutions that have previously been linked with cold adaptation via an increase in protein flexibility. We found that these indices were significantly correlated with OGT at the whole genome level, although the sign of some correlations were opposite of the predicted positive correlation between temperature and the indices. Using these data, we fit a multiple linear regression model for OGT within the Colwelliaceae family that incorporates the three most informative amino acid indices: GRAVY, Aliphatic Index, and Acidic Residue Proportion. Additionally, a putative cold-adaptive gene cassette was identified that was likely introduced by horizontal gene transfer between two closely related clades with different OGTs. These contributions offer key insights into OGT variability and its underlying genomic foundation in the family Colwelliaceae.
    • Geochemical, spatial, and temporal relationships of the intrusives and meta-intrusives of the Pogo deposit, eastern Interior, AK

      Thompson, William D.; Newberry, Rainer; Keskinen, Mary; Mezger, Jochen (2020-12)
      The Pogo deposit is an intrusion-related gold deposit (IRGD) located approximately 90 km southeast of Fairbanks, Alaska. It consists mainly of shallowly NW dipping quartz veins hosted in amphibolite facies paragneiss and predominately granite orthogneiss bodies. To date the deposit has produced over 4 million ounces of gold. U-Pb zircon dating of the orthogneisses shows they have Devonian-Mississippian protolith ages. Dates from the metamorphic zircons, established by microprobe Th data and cathodoluminescence studies, constrain a mid-Cretaceous metamorphic event to ~116 Ma. Recrystallization of kyanite to sillimanite and zircon recrystallization indicates this was a large fluid flux event that predated mineralization by 10 million years. Due to the fine-grained nature of the intrusive rocks at Pogo, identifying rocks in hand sample proved problematic. By combining XRF analysis of the rocks' major and trace elements and age data from this and previous studies, I identified and differentiated several suites of igneous rocks. The oldest is peraluminous granite, emplaced at ~2.5 ± 0.5 kb at ~109-107 Ma, predating mineralization at 104 Ma at a pressure of 2.0 kb. Non-peraluminous granite is less common and of uncertain relationship to the peraluminous granite. Next, temporally, is a body named the Football pluton (and associated dike) of granodioritic to tonalitic composition, emplaced at 2.0 ± 0.5 kb at 103 ± 2 Ma. Not only indistinguishable from age and depth of mineralization, a dike of this body is present downdip underneath the Liese veins (main zone of mineralization), making it the most likely candidate for being the causative pluton for mineralization. The final mid-Cretaceous body is the Liese pluton (and associated dikes), of quartz diorite to tonalite. This forms a large body with E-W dikes cutting the Pogo mineralization and post-dating it at 95.4 ± 0.2 Ma, emplaced at a pressure of 1.0 kb. Thermobarometry and radiometric dating indicate a consistent uplift rate of about 0.6 mm/year during the mid-Cretaceous, 116 to 95 Ma. Initially an extensional event, subduction-related magmatism began at about 105 Ma. At the same time, the thrust faults were re-activated as low angle normal faults that apparently acted as pathways for the Liese mineralization.
    • Gravity and mountain waves and their phenomena in Fairbanks, Alaska: a comparative case study

      Brink, Hannah; Mölders, Nicole; Fochesatto, Javier; Polyakov, Igor; Newman, David (2021-05)
      The area of Fairbanks, Alaska is in a valley surrounded by mountains from the Alaska Range to the South, the Brooks Range to the north, and the eastern mountain range that extends into Canada. The topographical nature of this subarctic area brings unique atmospheric features to the Fairbanks area, such as temperature inversions and mountain wave perturbation. This thesis will examine two case studies of gravity wave phenomena; one a mountain wave from December 2017, the other a non-mountainous gravity wave from December 2016. Data was collected from radiosondes and Global Data Assimilation Model (GDAS) maps, with the former smoothed for comparative purposes. Profiles of the atmosphere were created to see direct changes that mountain waves create on atmospheric parameters and the subarctic valley area. Methods were explored to separate mountain wave buoyancy effects from other atmospheric buoyancy effects, and then used to compare mountain wave buoyancy effects with frontal motion buoyancy effects. In all cases, the polar jet stream was found to have signicant influence on gravity wave effects in the Fairbanks area. Attention to the polar jet stream location can help predict mountain wave effects and associated atmospheric perturbations. Weather phenomena localized by altitude due to gravity waves were also identified. These include localized short-term surface pressure systems on the day of gravity wave cases. Mountain waves were found to be strongly linked to synoptic temperature events in Fairbanks, Alaska, and the mountain wave case was found to have more pronounced atmospheric effects than the gravity wave case.
    • Growth and reproductive rates of calanoid copepods in the northern Bering and southern Chukchi Seas

      Poje, Alexandra; Hopcroft, Russ; Coyle, Kenneth; Danielson, Seth (2020-08)
      Egg production and copepodite growth rates were measured for the calanoid copepods Pseudocalanus spp., Calanus marshallae/glacialis, and Metridia pacifica in the northern Bering and southern Chukchi Seas during June of 2017 and 2018. For all taxa, instantaneous growth rates generally decreased with increasing copepodite stage, though the differences between most stages was not significant. The growth rates for Pseudocalanus spp. averaged 0.03 ± 0.002 day⁻¹, Calanus spp. 0.09 ± 0.004 day⁻¹, and M. pacifica 0.05 ± 0.03 day⁻¹. Egg production rates increased with prosome length for all species, but when standardized to body weight this trend reversed. All Pseudocalanus species had similar weight-specific egg production (SEP): 0.18 ± 0.01 for P. acuspes, 0.15 ± 0.00 for P. newmani, and 0.11 ± 0.02 for P. minutus. The SEP for Calanus was considerably lower, 0.09 ± 0.01, while for M. pacifica it was 0.11 ± 0.01. These rates suggest considerable discrepancies between growth rates and egg production weights that we propose are due to differences in life history strategies. Pseudocalanus reproduce nearly year round, they appear to invest less in somatic growth, preferring to quickly reach their adult stage where they invest heavily into reproduction. Calanus spp. have 1 or possibly 2 generations per year in this region, they invest more into somatic growth in order to ensure their population is ready for a reproductive season timed to the spring phytoplankton bloom. The more omnivorous M. pacifica is also likely limited to 1 or 2 generations, although their ability to thrive on a wider range of food sources than Calanus seems to allow for relatively higher investment in reproduction and perhaps lower investment in somatic growth. Consistent with other studies, global growth models do not match our observations particularly well, likely because they are dominated by egg production estimates at lower latitudes.
    • Habitat use of spectacled eider broods in relation to salinity and food availability on the Yukon-Kuskokwim Delta, Alaska

      Graff, Nathan R.; Lindberg, Mark; Hollmén, Tuula; Knut, Kielland (2021-08)
      Spectacled eiders (Somateria fischeri) nest and raise their broods in coastal areas of the Yukon-Kuskokwim Delta, which may be vulnerable to projected climate change effects of increased temperatures, storms, and sea level rise. These changes in turn will likely affect wetland salinity levels used by ducklings, which are a potential constraint to growth and survival of young ducklings while their salt glands develop. To examine this potential concern, I investigated spatial and temporal pond salinity dynamics, food availability, and habitat use of spectacled eider broods at Kigigak Island, AK during 2011-2012. I found that salinity was highly variable across the island, ranging from 0-23.9 ppt and averaged 4.9-12.9 ppt in ponds at brood observation sites during the first 30 days of brood rearing. Salinity typically increased through the summer across all habitat types, but at the highest rate in high sedge habitat. The most common invertebrate taxonomic groups included Eurytemora, Harpacticoida, Annelida, and Chironomidae, which were found in nearly all ponds sampled with salinity ranging from 0.7- 16.1 ppt. Neither salinity nor invertebrate abundance explained pond foraging use by broods. Additionally, I used robust design occupancy models to estimate brood foraging patterns. Pond occupancy ranged from 0.43-0.59 between years. Overall, brood use of ponds was not dictated by salinity levels or invertebrates present, suggesting that most ponds provide suitable brood rearing habitat. I did not detect any obvious constraint to pond use within brood rearing habitat under the environmental conditions encountered.
    • Health benefits of the hunter/gatherer lifestyle

      Coker, Melynda Sheri; Greenberg, Joshua; Brinkman, Todd; Duffy, Lawrence; Lindberg, Mark (2021-08)
      The Hunter/Gatherer Lifestyle has long been associated with positive health benefits. I measured specific metabolic parameters associated with this lifestyle, highlighting lean tissue preservation. Severe loss of lean tissue mass (LTM) (sarcopenia) is a progressive, multifactorial disease presenting with decreased functional performance, age-related bone loss, increased falls and fractures, obesity, type II diabetes mellitus, depression, hospitalization, and even mortality. Degradation of LTM, often accompanied with obesity, is cost-prohibitive emotionally, physically, and financially. To counteract LTM deterioration, a positive net protein balance (NB) must be created through increased protein synthesis or suppressed protein breakdown. I utilized isotope tracer infusion methodology to compare equivalent serving sizes of wild, freerange red meat (FR) to grain-fed commercial meat (CB) on human NB. I observed that FR elicited significantly higher NB than CB due to greater suppression of protein breakdown. I next asked if an unscripted 8-12-day Alaska expeditionary backcountry hunt (ABEH) for moose, caribou, and sheep hunters would be executed in negative energy balance and positively influence metabolic markers while maintaining LTM. I found that energy expenditure was far greater than intake and contributed to reductions in body weight, adipose tissue, serum lipids, and intrahepatic lipid, while preserving LTM. Finally, I asked if a proprietary drink with a unique amino acid formulation (EMR) similar to FR could elicit fat loss and LTM maintenance in a cohort unlikely to gain access to FR. EMR or Optifast® was provided once per day to obese, elderly individuals. With no additional manipulations and in one month, there was a net gain of thigh muscle cross-sectional area and significant reductions in total and visceral fat mass. Concluding, I sought specific metabolic outcomes derived from distinct aspects of the understudied hunter/gatherer lifestyle (i.e., FR, ABEH, EMR). I found positive influences on health which would contribute to LTM preservation during aging, decreasing individual, family, and societal burdens linked to loss of LTM. These findings provide increased emotional, physical, and financial value to the hunter/gatherer lifestyle.
    • Holy American burnout! - essays

      Enfield, Sean; Farmer, Daryl; Johnson, Sara; Schell, Jennifer (2021-05)
      Neither students nor educators are ever just the body which occupies a classroom. Both bring their personal histories as well as the socio-cultural and political climates in which they live. The essays in this collection explore the author's development as both a student and as an educator, revolving often around themes of race and religion. At the core of this narratively linked collection of essays is the author's first-year teaching experience in which he worked as an 8th grade literature teacher at a private, quasi-religious school. Cultural and music criticism provide the bridge by which these personal essays broaden their scope into their larger socio-political landscape. It evokes sources as disparate as the disgraced Disney film, Song of the South; Igor Stravinsky's ballet, The Rite of Spring; and the Pulitzer-winning hip hop artist, Kendrick Lamar. These sources serve as the prism with which the author navigates his personal experiences with racism and teaching Muslim students during the mounting of the 45th presidents anti-Islamic, anti-immigrant campaign. All in all, these essays seek to illuminate the many ways learn, develop, and relate to each other in America, looking for new ways to navigate this broken system which so often dead ends in burnout.
    • How aspen tree height influences aspen leaf miner (Phyllocnistis populiella) oviposition and performance

      Tundo, Giovanni; Doak, Pat; Wagner, Diane; Breed, Greg (2021-05)
      Under the optimal oviposition theory, insects are expected to lay eggs on hosts that maximize the success of their offspring. Tree height is known to be an important factor influencing the distribution of phytophagous insects because some species perform better at a distinct range of heights. This difference in performance could lead to incorrect estimates of population parameters if surveys are only conducted on one host plant height. Aspen leaf miners (Phyllocnistis populiella) have undergone a major outbreak in interior Alaska over the last two decades. We quantified patterns of aspen leaf miner oviposition and juvenile survival over 2 years and found that aspen leaf miners were approximately 1.5 times more likely to survive on tall trees than short trees. Parasitism and both egg and larval predation were lower on tall trees. Aspen leaf miners on tall trees also had larger pupal masses than those on short trees. Although aspen leaf miners performed better on tall trees, the number of eggs laid per leaf did not significantly differ by tree height. There were no significant differences in leaf foliar nitrogen between tall and short trees. We also found little differences in wind speed between tall and short trees that could explain ovipositional patterns. Ovipositional patterns may partially reflect the difference in phenology between tall and short aspen trees. Aspen leaf miners only lay eggs on new leaves. Tall aspen trees leafed out 7 days earlier on average than short aspen trees, and tall trees, unlike short trees, ceased to produce new leaves after budburst. Consequently, there was little overlap in the availability of tall and short aspen trees for oviposition, so even if aspen leaf miners have a preference for laying more eggs on tall than short trees, they can only act on it during the short time period when tall trees are available for oviposition. The results suggest that population projections based on data collected from only short trees may underestimate future aspen leaf miner population growth due to lower juvenile survival rates and pupal masses on short trees. More broadly, the results highlight the importance of examining multiple tree heights when studying the performance and population dynamics of phytophagous insects. They also suggest that phenological differences between plants may constrain insects from using higher quality hosts.
    • Human paleoecology from the late glacial to early holocene, Tangle Lakes, Alaska

      Darcy, Audra J.; Reuther, Joshua D.; Bigelow, Nancy H.; Clark, Jamie L. (2021-08)
      This study examines paleoenvironmental change from the Late Glacial to the Early Holocene in the Tangle Lakes region of interior Alaska to explore changes in resource distribution and impacts on prehistoric hunter-gatherer subsistence patterns in upland settings (>500 masl). In interior Alaska, prehistoric hunter-gatherer subsistence economies were organized around the procurement of large herbivores (bison, caribou, elk, and moose), which were primarily regulated by habitat availability. Changes in habitat availability altered the distribution of key faunal resources, necessitating shifts in land-use strategies. The palaeoecological record from Glacier Gap helps contextualize resource distribution within dynamic landscapes by identifying changes in habitat availability for grazing, mixed-feeding (bison, caribou, elk), and browsing (moose) herbivores. This study applies pollen analysis, as well as carbon and nitrogen isotope analysis, of lake and peat deposits to reconstruct paleoenvironmental change from ~14,000 to ~6,000 Cal yr. BP. Results indicate grazing habitats persisted until approximately ~13,500 Cal yr. BP, which allowed for initial expansions of bison and elk, but habitats became mixed following the appearance of birch shrubs. Existing archaeological data indicate that initial use of upland regions coincided with expansion of bison and elk habitat, which would have represented large-bodied, predictable sources of food. As shrubs continued to expand, grazing and browsing habitats became increasingly fragmented in a mixed-feeding period between ~13,000 to ~10,000 Cal yr. BP. Fragmentation of bison and elk habitats made these species less predictable on the landscape, which likely led to the abandonment of the Tangle Lakes. A shift from mixed-feeding to browsing habitats occurred following the Holocene Thermal Maximum at ~10,000 Cal yr. BP with increasing shrub growth and the expansion of peat, supporting caribou and moose populations. Settlement patterns indicate re-occupation of the Tangle Lakes, and intensified use of uplands, when browsing specialists became more predictable, and subsistence focus shifted to the procurement of caribou ~6,000 Cal yr. BP. Taken together, grazing and browsing habitats represent homogeneous environments where resources were more abundant and predictable for hunter-gatherers, while mixed-feeding habitats represent heterogeneous environments where herbivores were fragmented and less abundant or predictable on the landscape.
    • I hear what you're saying: evaluating the couple validation training (CVT), a brief behavioral intervention

      McKay, Jessica; Worrall, Michael J.; Gifford, Valerie; Lopez, Ellen; Eldridge, Gloria; Fitterling, James (2020-12)
      Couple distress has strong implications for individual, couple, and family functioning. Research has found couple relationship education to be an effective tool in alleviating couple distress, thus improving the quality of couple communication and problem-solving skills. Couple relationship education has been shown to be more cost-effective and less likely to provoke the typical fears couples face when considering couple therapy, increasing the likelihood of receiving needed help. This study used a brief, highly structured behavioral intervention to teach partners to identify and code effective and ineffective ways of communicating. The primary research question sought to determine whether learning a structured coding process would lead to observable behavior changes through increased use of validating communication behaviors and decreased use of invalidating communication behaviors during a conflict-based discussion with a partner. Secondary questions pertaining to effective communication, relationship satisfaction, and training satisfaction were also explored. Participants were 16 couples who identified as being in a committed (nonmarried), heterosexual relationship, ages 18-40 (M = 26.00, SD = 6.61), and who were interested in improving their communication skills. The study used a quasi-experimental, three-level multilevel model to assess for dependence and change in the dependent variable (communication behaviors) over time. Hypothesis testing using the multilevel model found a significant difference between intervention and control groups pre to post workshop. However, inconsistent with the hypothesis the control condition increased validations significantly while the intervention condition showed no significant change over time. No other significant difference between groups were found. Other areas of interest emerged from the data. Couples self-reported a benefit from engaging in the study; over 85% of couples reported feeling satisfied with their experiences in the workshop and gave positive feedback about their experience. Future studies may explore the mechanisms of change and the possibility of additional clinically relevant changes which are not measured in this study. Keywords: relationship education, couples, validation, invalidation.
    • Identifying spatial patterns of storm driven flooding and erosion at Nelson Lagoon, Alaska

      Bogardus, Reyce C.; Maio, Chris; Mann, Daniel; Overbeck, Jacquelyn (2021-05)
      This project quantifies localized potential for shoreline change and flooding at Nelson Lagoon, a small fishing community located on the Bering Sea coast of the Alaska Peninsula. The overall goal of this project is to generate societally relevant and locally applicable map and data products through synergistic relationships with federal, state, private, tribal, and public partners. This project intends to substantiate anecdotal observations by local residents, with the ultimate goal of informing erosion and flooding mitigation efforts moving forward. Long-term trends of shoreline change were measured using multi-temporal orthorectified aerial imagery between 1983 and 2019, while annual changes in shoreline morphology were measured via cross-shore elevation profiles using a survey grade Real-time-Kinematic Global Navigational Satellite System (RTK-GNSS). Shoreline positions were extrapolated using linear regression techniques. A digital surface model (DSM) of the community was derived using Structure-from-Motion (SfM) with >2,400 aerial images collected with an Unmanned Aerial Vehicle (UAV) and used to assess flooding vulnerability after being geodetically referenced and related to a local tidal datum computed by this project. New and existing topographic and bathymetric datasets were compiled and refined into a 6,000 km² topobathymetric "seamless elevation" model of the Nelson Lagoon area, over which storm-tide induced currents were simulated using Delft3D FM Suite HMWQ. Remote sensing records indicate that the Nelson Lagoon spit elongated by more than 800 m and narrowed with an average Net Shoreline Movement (NSM) of -16.9 m between 1983 and 2019 (distal end not included). Though, NSM values show high variability ([sigma] = 21.9 m) and the lagoon and seaward sides of the spit are exhibiting very different erosional regimes. On both sides of the spit, episodes of rapid erosion mainly occurred during high storm-tide events that coincided with significant wave action. For this reason, the long-term erosion rates ultimately reflect the combined erosional impact of just a few storm events. Sand dunes in the supratidal zone on both sides of the spit are eroding at the vegetation line while the dune face retreats landward. By assessing erosion and flooding vulnerabilities for the Nelson Lagoon community, this study adds to an ever-growing database of such assessments statewide; which, ultimately, advance our understanding of regional coastal change in a shifting environment.
    • If women were dragons: a study of the conquest of women and dragons in Ragnar's saga, the Volsunga sagas, and the Nibelungenlied

      Baalke, Claire-Elise A.; Harney, Eileen; Stanley, Sarah; Riley, Terry (2020-08)
      This thesis is a study displaying the connections between female characters and dragons in Old Norse and Middle High Germanic literature. The main associations that I examine are the ways that female characters and dragons share the characteristics of greed or hoarding, prophetic sight or supernatural power, and "monstrosity" or "Otherness." The fundamental argument is that the women and dragons have common characteristics which define them as dangerous and thereby cause the men or heroes of the tale to feel the need to silence or depower them through conquest. Typically, the dragon is the barrier between the woman and the hero in these kinds of stories and thus the dragon is violated or slain in a manner that represents quashing of feminine power. I argue that the dragon is defeated as proxy to the defamation or depowering of deviant female characters, non-conforming women who do not follow socially accepted gender roles. The texts used to present these arguments are The Poetic Edda, The Volsunga Sagas and its prequel Ragnar's Saga, and The Nibelungenlied. In the majority of dragon stories there is a direct relationship between a dragon and a female character, commonly a princess who is being protected or arguably kept captive by the dragon. I argue, however, that these characteristics of the dragon, which are imitated by female characters, can manifest metaphorically as well. In the texts considered in which there are no "real" or physical dragons, a woman stands in as the metaphorical dragon that must be defeated.