• Fire-severity effects on plant-fungal interactions: implications for Alaskan treeline dynamics in a warming climate

      Hewitt, Rebecca E.; Hollingsworth, Teresa; Chapin, F. Stuart III; Rupp, T. Scott; Taylor, D. Lee (2014-08)
      Understanding the complex mechanisms controlling treeline advance or retreat in the Arctic and Subarctic has important implications for projecting ecosystem response to climate change. Changes in landcover due to a treeline biome shift could alter climate feedbacks and ecosystem services such as wildlife and berry habitat. Major sources of uncertainty in predicting treeline advance or retreat are the controls over seedling establishment at treeline and in tundra. One often-overlooked yet physiologically important factor to seedling establishment is the symbiosis with ectomycorrhizal fungi (EMF), the obligate mycobionts of all boreal tree species. EMF provide soil nutrients and water to seedlings and protect against pathogens, enhancing their growth and reducing drought stress. The availability of these critical mycobionts may be limited across the forest-tundra ecotone and by disturbance events such as wildfire. Wildfires are the primary large-scale disturbance in Alaskan boreal forests and are increasingly prevalent in tundra and at treeline. Fire is the major driver of boreal tree seedling recruitment; however, fire also alters the community structure and reduces biomass of EMF, especially after high-severity fires. To investigate the potentially critical role of EMF in seedling establishment at and beyond current treeline in Alaska, I conducted two observational studies and one experimental study that address how fire-severity influences EMF community structure and plant-fungal interactions. These studies indicated that shrubs that survived and resprouted after fires at treeline and in tundra were a source of resilience for EMF diversity and function. Shrubs maintained latesuccessional stage EMF taxa, and the EMF taxa associated with shrubs at treeline were compatible with tree seedlings that naturally established after fire. Many of the EMF taxa that were shared by seedlings and shrubs were present across the low Arctic, suggesting that EMF compatible with boreal tree species are not limited within the predicted geographic range of treeline expansion. Additionally, I found that seedling growth was correlated with post-fire fungal inoculum. Seedling growth was promoted by EMF inoculum provided by resprouting shrubs after fire. However, when fungal inoculum lacked EMF in post-fire tundra soils, seedling biomass was related to the negative effect of soil pathogens and the positive influence of dark septate endophytes. Together these results illustrate the important role of resprouting tundra shrubs as fungal nurse plants for establishment of boreal tree species at and potentially beyond current treeline, and that biotic factors such as EMF-tree interactions are important to seedling performance. My results suggest that the inclusion of biotic effects, like plant-fungal interactions, in simulation models of treeline dynamics will improve the accuracy of predictions of forestation and associated landscape flammability with future warming in Alaska.
    • First Steps Into Late-Deafness: An Introductory Manual For Newly Deafened Adults

      Shannon, Candis; Cooper, Burns (2006)
      Late-deafened adults are individuals who lose their hearing in adolescence or adulthood. Whether the hearing loss is sudden or progressive, it forces immense psychosocial changes upon the individual, disrupting relationships and work, and impacting every area of the person's life. This manual serves as a guidebook for the newly deafened adult, giving her understanding, empathy and a road map to help make sense of the adjustment process. The first chapters detail what to expect during visits to the ear specialist and audiologist, and discuss the grieving process and the impact of deafness on identity formation. Information on how to develop new ways of communicating and how to build a support network is shared. An introduction to cochlear implantation, assistive technology, and legal rights for late-deafened adults follows. The manual closes with interviews of three late-deafened adults who share their journey into late-deafness.
    • First-generation effects on development time of outcrossing between geographically isolated and seasonally isolated populations of pink salmon (Oncorhynchus gorbuscha)

      Echave, Jesse D.; Gharrett, Anthony; Smoker, William; Adkison, Milo (2010-12)
      Bootstrap analyses of hatch data collected during two independent experiments revealed that hybridization between pink salmon (Oncorhynchus gorbuscha) breeding populations separated at either a large geographic scale or a fine temporal scale can influence development time. Restricted maximum likelihood estimators also revealed that sire, dam, cross, and parental interaction can influence genetic variance associated with development time at either scale. Few studies have investigated the extent of local adaptation that results from fine-scale ecological variation, the genetic underpinnings of that adaptation, or the potential impacts outbreeding at that level may have on fitness. We tested whether or not local adaptation contributed to genetic divergence among subpopulations of pink salmon that overlap temporally within the same spawning habitat (early-run fish and late-run fish within Auke Creek, near Juneau, Alaska) by determining whether or not outbreeding influenced development time (a fitness-related trait) in first-generation hybrids. We examined genetic divergence among populations isolated at a much broader scale (Pillar Creek on Kodiak Island, Alaska, and Auke Creek, 1,000 km great circle distance) as a more extreme reference to local adaptation. Results provide evidence that development time is locally adapted and expressed primarily in a locus-by-locus manner.
    • Fish bacterial flora identification via rapid cellular fatty acid analysis

      Morey, Amit (2007-08)
      Seafood quality can be assessed by determining the bacterial load and flora composition, although classical taxonomic methods are time-consuming and subjective to interpretation bias. A two-prong approach was used to assess a commercially available microbial identification system: confirmation of known cultures and fish spoilage experiments to isolate unknowns for identification. Bacterial isolates from the Fishery Industrial Technology Center Culture Collection (FITCCC) and the American Type Culture Collection (ATCC) were used to test the identification ability of the Sherlock Microbial Identification System (MIS). Twelve ATCC and 21 FITCCC strains were identified to species with the exception of Pseudomonas fluorescens and P. putida which could not be distinguished by cellular fatty acid analysis. The bacterial flora changes that occurred in iced Alaska pink salmon (Oncorhynchus gorbuscha) were determined by the rapid method. Fresh fish contained up to 7 genera in which the aerobic plate counts (APC) was 3.04 log colony-forming units (CFU)/cm². As the fish spoiled, the APC increased to 6.60 log CFU/cm² and the flora was composed of P.fluorescens/putida, Psychrobacter immobilis and Shewanella putrefaciens. The Sherlock MIS rapidly and accurately identified seafood bacteria in fresh fish and can be used to monitor quality changes during iced storage of fish.
    • Fisheries management and fisheries livelihoods in Iceland

      Chambers, Catherine P.; Carothers, Courtney; Criddle, Keith; Seitz, Andrew; Helgadóttir, Guorun (2016-08)
      This dissertation explores the long-term implications of Iceland’s nationwide Individual Transferrable Quota (ITQ) system on rural communities and small-boat fishing livelihoods drawing on two years of ethnographic research in Northwest Iceland, a nationwide mailed survey of small-boat fishermen, and the compilation of fisheries human dimension indicator data for the lumpfish fishery. Results from ethnographic interviews and participant observation show that while there is a wide range of complex political, social, and environmental changes affecting coastal communities, the changes brought on by the ITQ system are perceived to have been particularly significant. Survey results suggest that the majority of small-boat fishermen perceive the ITQ system as serving the goal of wealth accumulation over the goal of resource conservation. Survey respondents and interview informants report high cultural connections to fishing through family history, but express concern that future generations may be precluded from fisheries livelihoods due to the prohibitory cost of entry into the ITQ system. Furthermore, survey responses, ethnographic interviews, and indicator data suggest that non-ITQ fisheries like the lumpfish fishery and the strandveiðar season do not serve as substantial platforms to support newcomers to fisheries. These non-ITQ fisheries can make individuals and communities more resilient by providing extra income and, at the same time, can offer social flexibility to access a fishery of cultural and historical value. However, survey and interview data also suggest that the strandveiðar fishery has resulted in new rifts in communities as Icelandic society struggles with differing perceptions of equitable access to marine resources. Survey and interview data show how decision-making power lies in the hands of a few dominant interest groups, leaving smallboat fishermen and rural communities at a disadvantage with little power to meaningfully influence national politics. Finally, the compilation of human indicator data in the lumpfish fishery highlights concepts of multiple (social, economic, and biological) goals in fisheries management and the benefits of participatory governance structures. Conclusions from this dissertation underscore the complexity of fisheries systems and the important role equity plays in sustainable fisheries management and governance.
    • Fishing for pollock in a sea of change: a history and analysis of the Bering Sea pollock fishery

      Strong, James; Criddle, Keith R.; Adkison, Milo D.; Kruse, Gordon H. (2011-08)
      The development and evolution of the eastern Bering Sea fishery for walleye pollock (Theragra chalcogramma) is retraced, its current economic and institutional structure is modeled, and the resiliency of that structure to substantive changes in pollock biomass and fuel costs is explored. Small variations in exvessel prices, total allowable catches, or allocation of catches between seasons and among industry sectors can lead to large changes to first wholesale revenues. Similarly, changes in fuel prices, changes in technology, changes in regulation, and changes in the spatial distribution of catches can lead to changes in harvesting or processing costs. Together, these changes affect the relative profitability of the inshore and offshore sectors, which can, in turn, affect the benefits that accrue to communities, the evolution of regulation, and create pressure to reallocate sector shares. The model indicates that first wholesale revenues are maximized when pollock harvests are maximized. However, legal barriers to the transfer of allocations between sectors can lead to under-harvests when product prices are low, fuel costs are high, or when the most productive fishing grounds are in the northwest regions of the eastern Bering Sea Exclusive Economic Zone.
    • Floating: ruminations from the open-air abyss

      Nyberg, Brandi Jo Petronio; Farmer, Daryl; Soos, Frank; Schell, Jennifer (2019-05)
      This thesis is a collection of environmentally centered personal essays, some of which are also research driven. Many of the essays within are place-based and several reflect on what the word 'home' means. The research-driven essays involved conducting literature reviews within academic journals and, in some cases, weaving that information with personal narrative. Throughout the thesis, there is a loose narrative arc that follows the author's nomadic wanderings and search for home. Although a home is never quite found, the author does find a deeper meaning on what it means to call a place 'home.' While the order of essays jumps from one place to the next geographically, they are ordered in a chronological sense - although not completely. Throughout the collection, the author is in direct conversation with many writers who have inspired her own writing, including Edward Abbey, Henry Thoreau, Barry Lopez, and Terry Tempest Williams. The purpose of this project is not only to entertain readers but also to educate. The author hopes that her writing will encourage readers to strengthen their connection to place and the environment and become engaged with pressing environmental issues, such as mountaintop removal mining.
    • Flood hazard hydrology: interdisciplinary geospatial preparedness and policy

      Petty, Timothy R.; Schnabel, William; Prakash, Anupma; Folger, Peter; Djokie, Dean (2017-05)
      Floods rank as the deadliest and most frequently occurring natural hazard worldwide, and in 2013 floods in the United States ranked second only to wind storms in accounting for loss of life and damage to property. While flood disasters remain difficult to accurately predict, more precise forecasts and better understanding of the frequency, magnitude and timing of floods can help reduce the loss of life and costs associated with the impact of flood events. There is a common perception that 1) local-to-national-level decision makers do not have accurate, reliable and actionable data and knowledge they need in order to make informed flood-related decisions, and 2) because of science--policy disconnects, critical flood and scientific analyses and insights are failing to influence policymakers in national water resource and flood-related decisions that have significant local impact. This dissertation explores these perceived information gaps and disconnects, and seeks to answer the question of whether flood data can be accurately generated, transformed into useful actionable knowledge for local flood event decision makers, and then effectively communicated to influence policy. Utilizing an interdisciplinary mixed-methods research design approach, this thesis develops a methodological framework and interpretative lens for each of three distinct stages of flood-related information interaction: 1) data generation—using machine learning to estimate streamflow flood data for forecasting and response; 2) knowledge development and sharing—creating a geoanalytic visualization decision support system for flood events; and 3) knowledge actualization—using heuristic toolsets for translating scientific knowledge into policy action. Each stage is elaborated on in three distinct research papers, incorporated as chapters in this dissertation, that focus on developing practical data and methodologies that are useful to scientists, local flood event decision makers, and policymakers. Data and analytical results of this research indicate that, if certain conditions are met, it is possible to provide local decision makers and policy makers with the useful actionable knowledge they need to make timely and informed decisions.
    • Floodplain assessment for the Teklanika and Toklat River project reaches in Denali National Park and Preserve, Alaska

      Schalk, Brian N. (2005-05)
      The National Park Service (NPS) is required to assess risks of flooding to existing and proposed structures within the boundaries of the NPS system. Within Denali National Park and Preserve (DNP & P), there are several large, braided rivers that require floodplain management. The objective of this investigation is to provide DNP & P with guidelines and methods that apply fluvial geomorphic, hydrologic, and hydraulic analysis in order to delineate flood hazard zones on this type of stream. Data collected from Teklanika and Toklat Rivers were used to develop a return period versus flood depth/bankfull depth curve and assess potential streambank erosion. Site specific data combined with this curve will enable NPS personnel to easily approximate flood hazard zones for the project reaches. The method can be applied to assess other flood hazard zones associated with other braided rivers with similar characteristics.
    • Fluid flow in oscillating cavities

      Ragunathan, Srivathsan (2003-12)
      Oscillatory flows have gained considerable research attention in the recent decades following an interest in transport enhancement in micro-electronic devices. Heat transfer enhancement due to flow modulation has an inherent advantage over conventional mechanical heat transfer components in terms of reduction in weight and space. The present work is aimed at studying fluid flow in oscillating square cavities as a first step towards heat transfer enhancement. A commercial CFD code, Fluent, was used to model a test case consisting of Stokes' second problem, with a source code written in the C programming language. The simulated results were in good agreement with the analytical results found in the literature. Since the description of an oscillatory boundary condition in complex geometries would prove to be a difficult exercise because of the presence of spanwise walls, Newton's second law of motion for accelerating reference frames was used. This method proved to be an effective one computationally and the results agreed well with the analytical results. The cavity problem was analyzed using Fluent with the Non-Newtonian formulation described above. Fluid dynamic characteristics were studied with respect to dimensionless parameters and they exhibited an explicit dependence on these parameters.
    • Fluvial and hillslope geomorphology of Hoseanna Creek Watershed, central Alaska

      Wilbur, Stephen Crawford (1995)
      Hoseanna Creek Watershed is rapidly eroding and provides excellent opportunities to describe and quantify hillslope and fluvial processes in the subarctic and in discontinuous permafrost terrain. High landslide and badland densities occur due to asymmetric geologic structure and weakly consolidated lithologies. Late Quaternary regional glaciofluvial processes and tectonism have changed local base level at least 100 m, inducing headward incision through weak lithologies and yielding high rates of sediment production. Earthflows, translational blocks, rotational blocks, lateral spreads or complex landslide types form in coal-bearing formations in response to lateral corrasion of toes by avulsing streams or to undermining of foot areas by headward incising streams. Slides undergo episodic resurgent activity when new lithostatic or hydrostatic thresholds are reached. Average horizontal displacement rates of seven slides monitored between 8/85 and 9/88 ranged from 0.2 m/yr in rotational blocks to 48 m/yr in the earthflows. Although unique sliding mechanisms are not apparent, permafrost and subarctic climate generate delays or catalysts for failure atypical of warmer climates. Freezing/thawing fronts affect soil strength and permeability; break-up/freeze-up processes affect the timing of water supply to the slide mass and affect development of aufeis-related ground-water pore pressures. Aspectual and lithologic variations combine to yield three geohydrologic subbasin types which govern discharge ranges. Regressions were performed on multiple sets of sediment-discharge (Ts-Q) data. Regression variance (r$\sp2$) was found to have a maximum natural threshold indicative of intrinsic variability. Wide ranges in Q (0.001 to 2350 cfs) and Ts (0.005 to 1600 g/l) necessitated log-log scales and power functions. Each geohydrologic subbasin has a unique Ts-Q relationship termed here the mean sediment concentration potential Cp. Systematic differences in regression parameters indicate that variations in spatial conditions define Cp, while systematic changes in Ts-Q regression residuals R (termed here the maintenance rate R$\sp*$) describe the temporal variability of Ts through time with respect to Cp. 50-95% of the annual sediment load is transferred during less than 3% of the year. Erosion rate indexes were established from peak load estimates; Nenana Gravel basins are eroding 260 times faster than schistose basins and ten times coal-bearing basins.
    • Focus On Form In Writing In A Third Grade Yugtun Classroom

      Moses, Catherine; Siekmann, Sabine (2010)
      This present research attempts to discover the effectiveness of focus on form in a Yugtun First Language third grade classroom. The procedures for this particular research included two series of tasks, each focusing students' attention on a particular grammatical structure. The series includes a pretest, a discovery phase, a teacher guided mini lesson, a paired task, an individual post task and a delayed post task. Data include students' scores on the pre, post and delayed post test as well as video recordings of whole class activities, and audio recordings of student dyads as they work on the collaborative task. In my research I found how I, as a Yugtun classroom teacher, could help my students focus on areas of language features they seem to have trouble with. I learned I could use focus on form through feedback and questions. I also found that the Yugtun word endings mun/nun were rather difficult for the Yugtun third graders. As a result I encourage all Yugtun teachers as well as other language teachers to attend workshop or training on language acquisition in order to get a better understanding of what it means as they endeavor to help their students learn effectively.
    • Focus On Form Through Singing In A First Grade Yugtun Immersion Classroom

      Oulton, Carol S.; Siekmann, Sabine (2010)
      This study examines the impacts of singing as a focus on form in the Yugtun genitive endings. Genitive case endings refer to the case of ownership, such as in the sentence "My mother's eyes." The belief of this research is that singing will help the students to focus on form in the oral performance of the first grade second language learners of Yugtun. All the students in the classroom participated in the study. Their accuracy and progression were measured prior to teaching two songs with a pretest interview. After teaching of the songs, the students composed couple songs where the genitive forms were examined. A posttest and a delayed test were administered after the instructions of the songs. The results support the previous studies that focus on form can provide accuracy to second language development.
    • Foliage and winter woody browse quality of an important Salix browse species: effects of presence of alder-derived nitrogen and winter browsing by Alaskan moose (Alces alces gigas)

      Burrows, Justin; Kielland, Knut; Wagner, Diane; Ruess, Roger (2019-12)
      In this study, I examined the relationship between soil nitrogen and winter browsing by moose on the physical and chemical characteristics of Salix alaxensis; specifically stem production, leaf nutritional quality, and stem nutritional quality of tissues produced the following growing season. I measured stem biomass production the 2013 growing season and offtake during the 2013-2014 winter browsing season at 16 sites on the Tanana River floodplain near Fairbanks, Alaska. I revisited the sites the following summer and autumn to assess regrowth and to collect soil, foliage, and stem samples. Browsing intensity and total soil nitrogen were similar in sites with and without alder, a nitrogen-fixing shrub. Soil nitrogen and browsing intensity were not consistently related to changes in stem or leaf quality, although there were significant relationships in some subsets. Soil nitrogen and browsing intensity also did not have consistent relationships with stem regrowth the following growing season. These results indicate that S. alaxensis growing in this system are able to recover from a naturally broad range of browsing utilization, including very high levels of offtake, and continue to produce nutritious leaves and stems.
    • The food habits, age, and growth of three midwater fishes (Stenobrachius leucopsarus, Stenobrachius nannochir, and Leuroglossus schmidti) from the Southeastern Bering Sea

      Adams, Albert E. (1979-08)
      The food habits, age, and growth of two lanternfishes (Stenobrachius leucopsarus and Stenobrachius nannochir nannochir) and the northern smoothtongue (Leuroglossus schmidti) from the southeastern Bering Sea are examined in order to assess the trophic importance of these organisms at the northernmost limit of their distribution. All three species prey exclusively upon zooplankton. The order of predominant dietary components is: copepods, euphausiids, ostracods, and amphipods (S. leucopsarus); copepods and ostracods (S. n. nannochir); and larvaceans, copepods, and ostracods (L. schmidti). Seasonal and diurnal-nocturnal dietary variations are noted for Stenobrachius leucopsarus. Maximum growth of each species occurs during the first year and is followed by decreased but very uniform growth in the remaining years of life. Sexual maturity is attained at age four by both lanternfish and at age three by Leuroglossus schmidti. The greatest longevity of S. leucopsarus and L. schmidti is six years; S. n. nannochir may only reach age five.
    • Food of the Pacific cod Gadus macrocephalus Tilesius near Kodiak Island, Alaska

      Jewett, Stephen C. (1977-08)
      The Pacific cod, Gadus macroaephalus, from the Kodiak Alaska continental shelf, feeds predominantly on demersal fishes and crustaceans. The most frequently occurring food groups in Pacific cod stomachs in order of decreasing frequency of occurrence are fishes, crabs, shrimps and amphipods. The snow crab, Chionoecetes bairdi, is the most frequently occurring food species. Frequency occurrence of food items in cod stomachs is enumerated within each of three cod size groups - 33 to 52 cm, 53 to 72 cm, and 73 to 92 cm. Fishes and cephalopods increase in frequency occurrence with increasing cod size. Amphipods and polychaetes are more frequently found in smaller fish. In general, the incidence of euphausiids and mysids decrease with increasing cod size. Crabs, shrimps, pelecypods and gastropods increase in frequency occurrence from the small (33 to 52 cm) to the medium size fish (53 to 72 cm) and again decline in importance among larger cod (73 to 92 cm).
    • Food, sex, death, and quest: the literary legacy of Sir John Franklin

      Long, Maureen Eleanor (2003-05)
      The story of Sir John Franklin, nineteenth-century British Arctic explorer, has been reinterpreted and reworked by poets, novelists, essayists, and dramatists for more than a century and half. This thesis is an attempt to discover the character and significance of the literary legacy of Sir John Franklin by exploring authors' uses of four common tropes: food, sex, death, and quest. In analyzing these tropes, this thesis focuses primarily on five works of contemporary Canadian literature: Margaret Atwood's short story, "The Age of Lead"; Gwendolyn MacEwen's radio verse play, Terror and Erebus; Geoff Kavanagh's play, Ditch; Mordecai Richler's novel, Solomon Gursky Was Here; and Rudy Wiebe's novel, A Discovery of Strangers. In addition, other works of literature are considered. An appendix lists more than fifty creative works that incorporate Sir John Franklin.
    • Foods and foraging ecology of oldsquaws (Clangula hyemalis L.) on the arctic coastal plain of Alaska

      Taylor, Eric John (1986-09)
      The study was conducted from June to September during 1979 and 1980 in the the West Long Lake area of the National Petroleum Reserve-Alaska. Additional oldsquaws were collected in the inland wetlands near the northwest boundary of the reserve at Ice Cape. West Long Lake and the adjacent Goose Lake are located 15 miles south of the Beaufort Sea and immediately west of Teshekpuk Lake.