Recent Submissions

  • Human well-being in recreation: an investigation of the expectancy-valence theory

    Harrington, Andrew M. (2011-05)
    Over the past 50 years, numerous approaches exploring the recreation experience have offered a multitude of concepts and terminology, resulting in a debate over which best represent recreation behavior. This study adopts one of these approaches, the motivational approach, and explores its underpinning theory, expectancy-valence; addresses its limitations presented in the literature; and investigates the potential for the integration with other approaches. A modified analytic induction methodology was applied to address five hypotheses developed to address study questions. Longitudinal, qualitative data were collected through two separate interviews one week apart with 16 individuals that captured their thoughts regarding their recreation activities. A codebook was developed and a kappa statistic revealed an acceptable (K = 0.61 to 0.80) level of inter-coder reliability. Codes were developed based on constructs from the expectancy-valence framework prior to examining the transcripts. Evidence of these codes in the transcripts provided support for the theory. Consistent with modified analytic induction, some hypotheses were confirmed, while one was modified when evidence to the contrary was found. Further examination of the data revealed the potential for integration of other approaches.
  • Arctic sea ice: satellite observations, global climate model performance, and future scenarios

    Rogers, Tracy S.; Rupp, Scott (2011-08)
    This thesis examined Arctic sea ice trends through observational records and model-derived scenarios. A regional analysis of Arctic sea ice observations 1980-2008 identified regional trends similar to the pan-Arctic. However, winter maximum (March) extent in the Atlantic quadrant declined faster. Through an analysis of Atlantic Ocean temperatures and Arctic winds, we concluded that melting sea ice extent may result in increased Atlantic Ocean temperatures, which feeds back to further reductions in Atlantic quadrant extent. Further, Arctic winds do not appear to drive Atlantic ice extent. We evaluated performance of 13 Global Climate Models, reviewing retrospective (1980-2008) sea ice simulations and used three metrics to compare with the observational record. We examined and ranked models at the pan-Arctic domain and regional quadrants, synthesizing model performance across several Arctic studies. The top performing models were able to better capture pan-Arctic trends and regional variability. Using the best performing models, we analyzed future sea ice projections across key access routes in the Arctic and found likely reduced ice coverage through 2100, allowing increasingly longer marine operations. This unique assessment found the Northwest and Northeast Passages to hold potential for future marine access to the Arctic, including shipping and resource development opportunities.
  • Pairwise comparisons of shrub change across alpine climates show heterogeneous response to temperature in Dall's Sheep range

    Melham, Mark; Valentine, Dave; Panda, Santosh; Brinkman, Todd (2019-12)
    Encroachment of woody vegetation into alpine and high latitude systems complicates resource use for specialist wildlife species. We converted Landsat imagery to maps of percent shrub cover in alpine areas of Dall's sheep (Ovis dalli dalli) range. We then compared percent cover to interpolated climate data to infer drivers of shrub change between the 1980s and 2010s and determine if that change is occurring at different rates in climatically distinct alpine areas. We identified areas spatially interconnected by their mean July temperature intervals and compared their rates of shrub change, finding net rates of shrub growth were higher at temperatures notably above shrub growing season minimums. Along a climatic gradient, high precipitation areas had highest net shrub change, Arctic areas followed, while alpine areas of interior Alaska and the cold Arctic showed the least amount of net shrub change at these higher temperatures. Despite the requirement of higher temperatures for shrub growth, temperature and net shrub change displayed different relationships across the range wide climatic gradient. In areas of rapid climate warming, such as the Arctic and cold Arctic, the linear correlation between shrub change and temperature was highest. In the high precipitation areas where temperatures have been largely above growing season minimums during the study period, precipitation had the strongest linear correlation with shrub change. High latitude studies on shrub change focus primarily on expansion in the Arctic, where increased greening trends are linked to higher rates of warming. We provide the broadest climatic examination of shrub change and its drivers in Alaska and suggest shrub expansion 1) occurs more broadly than just in areas of notable climate warming and 2) is dependent on different environmental factors based on regional climate. The implications for Dall's sheep are complicated and further research is necessary to understand their adaptive capacity in response to this widespread vegetative shift.
  • Planning for positive outcomes: testing methods for measuring outdoor recreation preferences on public lands

    Wright, Roger Bryant; Fix, Peter J.; Little, Joseph M.; Dodge, Kathryn (2019-08)
    Outcomes-Focused Management is based on the idea of four levels of demand for recreation: demand for recreation activities, recreation settings, recreation experiences, and lasting benefits of recreation. Public lands can provide the setting, and thus the opportunity for people to engage in meaningful outdoor recreation activities to realize desired experiences and lasting benefits. Implementation of this management framework requires identifying desired outcomes and understanding how management of public lands recreation settings affects visitors' ability to realize them. This thesis addresses the two tasks. The Fairbanks Community Recreation Study investigated current methods of identifying demands for different types of recreation trips, revealing two key shortcomings. First, demand studies often rely solely on activity participation data and thus fail to account for latent demand and desires for meaningful experiences and benefits. Second, data from demand studies are either too general to be useful in site management, or too specific to one site to account for the range of needs within a community. An online survey was developed to characterize salient and latent demands for outdoor recreation in the context of the greater Fairbanks, Alaska community. A unique survey format allowed respondents to describe their hypothetical "ideal" outdoor recreation trips, the required setting characteristics, and what actual places in the region might realistically provide such a trip. Trip profiles yielded a typology of desired recreation for the region. By connecting these types of trips to real places, local land managers can identify which demands they are uniquely equipped to provide for and how to better cater to latent demands. To address the task of measuring the effectiveness of outcomes-focused management practices, an exploratory factor analysis was conducted on data from 13 recreation benefits surveys collected at recreation areas in three western states. Factor structures among individual studies converged on two primary domains of Personal Benefits of recreation and Community Benefits from recreation, each containing a number of potential subdimensions. By identifying latent factors of the recreation benefits construct the study brings research closer to developing and validating a survey instrument to measure lasting beneficial recreation outcomes to individuals and their communities.
  • Crop modeling to assess the impact of climate change on spring wheat growth in sub-Arctic Alaska

    Harvey, Stephen K.; Zhang, Mingchu; Karlsson, Meriam; Fochesatto, Gilberto (2019-05)
    In the sub-arctic region of Interior Alaska, warmer temperatures and a longer growing season caused by climate change could make spring wheat (Triticum aestivum L.) a more viable crop. In this study, a crop model was utilized to simulate the growth of spring wheat in future climate change scenarios RCP4.5 (medium-low emission) and RCP8.5 (high emission) of Fairbanks, Alaska. In order to fulfill such simulation, in 2018 high quality crop growth datasets were collected at the Fairbanks and Matanuska Valley Experiment Farms and along with historic variety trial data, the crop model was calibrated and validated for simulating days to maturity (emergence to physiological maturity) and yield of spring wheat in Fairbanks. In the Fairbanks 1989-2018 (baseline) climate, growing season (planting to physiological maturity) average temperature and total precipitation are 15.6° C and 122 mm, respectively. In RCP4.5 2020-2049 (2035s), 2050-2079 (2065s), and 2080-2099 (2090s) projected growing season average temperature and total precipitation are 16.7° C, 17.4° C, 17.8° C and 120 mm, 112 mm, 112 mm, respectively. In RCP8.5 2035s, 2065s, and 2090s projected growing season average temperature and total precipitation are 16.8° C, 18.5° C, 19.5° C and 120 mm, 113 mm, 117 mm, respectively. Using Ingal, an Alaskan spring wheat, the model simulated days to maturity and yield in baseline and projected climate scenarios of Fairbanks, Alaska. Baseline days to maturity were 69 and yield was 1991 kg ha-1. In RCP4.5 2035s, 2065s, and 2090s days to maturity decreased to 64, 62, 60 days, respectively, and yield decreased 2%, 6%, 8%, respectively. In RCP8.5 2035s, 2065s, and 2090s days to maturity decreased to 64, 58, 55 days, respectively, and yield decreased 1%, 3%, then increased 1%, respectively. Adaptation by cultivar modification to have a growing degree day requirement of 68 days to maturity in RCP4.5 2035s and RCP8.5 2035s resulted in increased yields of 4% and 5%, respectively. Climatic parameters of temperature and precipitation per growing season day are projected to become more favorable to the growth of spring wheat. However, precipitation deficit, an indicator of water stress was found to stay similar to the baseline climate. Without adaption, days to maturity and yield are projected to decrease. Selection and/or breeding of spring wheat varieties to maintain baseline days to maturity are a priority to materialize yield increases in the area of Fairbanks, Alaska.
  • Multiresolution digital soil mapping of permafrost soils using a random forest classifier: an investigation along the Dalton Highway corridor, Alaska

    Paul, Joshua D.; Ping, Chien-Lu; Prakash, Anupma; Rossello, Jordi Cristobal; Libohova, Zamir (2018-12)
    In order to complete soil inventories in the remote permafrost zones of Alaska, there is a need to develop efficient digital soil mapping tools that can be applied over large areas using a minimum of ground truth data. This investigation first used a random forest classifier to test combinations of environmental input data at multiple resolutions (10m, 30m, and 100m). Five tiers of soil taxonomic units were predicted: Order, Suborder, Great Group, "Series Concept", and Particle Size Class. Model outputs are compared quantitatively via estimated out-of-bag accuracy, and qualitatively via visual inspection by soil scientists. Estimated out-of-bag accuracy ranged from ~45% to ~75%, with results improving when fewer classes were modeled. Model runs at 10m and 30m resolution performed comparably, with 100m resolution performing ~5-10% worse in most cases. Increasing the number of trees used, including categorical environmental input data (e.g. landforms), and replacement of environmental covariates with principal component analysis (PCA) bands did not significantly improve model performance. The random forest classifier was then used in a digital soil mapping pilot study along the Dalton Highway in northern Alaska. Parameters suggested in the initial study were used to predict multiple soil taxonomic classes from a basic collection of environmental covariates generated using high resolution (10m) satellite images and sparsely sampled pedon data. Covariates included maximum curvature, multiresolution valley bottom flatness, normalized height, potential incoming solar radiation, slope, terrain ruggedness index, and modified soil and vegetation index. Five tiers of soil taxonomic units were predicted: Order, Suborder, Great Group, "Series Concept", and Particle Size Class. Model outputs are compared quantitatively via estimated out-of-bag accuracy. Estimated out-of-bag accuracy ranged from ~45% to ~75%, with results improving when fewer classes were modeled. We suggest future research into optimized sampling to ensure an adequate distribution of samples across the feature space, and the incorporation of expert knowledge into accuracy assessments. Overall, digital soil mapping with random forest classifiers appears to be a promising method for completing the soil survey of Alaska.
  • A study of soil topo-sequences in the Steese and White Mountains of Alaska

    Geisler, Eric S.; Ping, Chien-Lu; Juday, Glen; Swanson, David (2018-08)
    The Steese Mountains of Alaska present a complex landscape on which to study soil formation and characteristics in relation to topographic position. The White and Steese Mountains of Alaska are located approximately 70 to 220 km northeast of Fairbanks. Ten toposequences with 3 or 4 sites each were described in the field, sampled, and analyzed in the laboratory in order to determine the relationship between soil morphology and soil-forming factors. Permafrost is discontinuous within the study area and vegetation ranges from tundra on summits to boreal stands of resin birch, quaking aspen, black spruce and white spruce along the lower elevations. There have been many wildfires over time that may have altered the soils and affected the vegetation successional patterns. The processes through which various soil patterns have formed and the unique characteristics of the soils are described here based on field data obtained from both burned and unburned sites. The analysis includes biophysical settings, parent material, texture and nutrient concentrations. Organic horizons were common on most of the transects and play a key role in the depth of the active layer where they exist. Nutrient concentrations are also closely tied to the presence and depth of the organic horizons. Some patterns described in other areas of the boreal region were not observed in this study. There were some soil properties that are not readily described under the current taxonomy protocols which are suggested to be added in a future revision of Soil Taxonomy.
  • Comparing Marine Mammal Co-Management Regimes In Alaska: Three Aspects Of Institutional Performance

    Meek, Chanda L. (2009)
    Arctic marine mammals and the communities that depend on them for subsistence are facing unprecedented rates of environmental change. Comparative studies of policy implementation are necessary in order to identify key mechanisms of successful environmental governance under challenging conditions. This study compares two federal agencies responsible for the conservation of Arctic marine mammals. Drawing on multiple methods, I develop in-depth case studies of the policy implementation process for managing bowhead whale and polar bear subsistence hunting. I examine how and why agency approaches to conservation differ and assess policy effectiveness. The analysis focuses on three aspects of institutional performance as drivers of policy outcomes: historical events, organizational culture, and structural relationships with stakeholders. The study begins by tracing the development of marine mammal management in Alaska through time. I find that definitions of subsistence developed under previous eras continue to shape debates over wildlife management in Alaska, confounding ecologically relevant policy reform. I next examine the roles of agency culture, policy history, and relationships with stakeholders in influencing how agencies implement contemporary harvest assessment programs. Findings suggest that the internal orientation of the U.S. Fish & Wildlife Service makes it more likely to retain control over management programs than the more externally oriented National Marine Fisheries Service. Furthermore, these policy approaches affect the development of social norms at the local level. Through a social network analysis, I demonstrate that the extent to which policy programs are integrated into the existing social networks of a village affects policy success. Hunter participation in and support for policies is stronger when there are local centers of coordination and meaningful policy deliberation. Finally, I assess existing policies regarding both species to examine whether or not contemporary policy approaches address key drivers of system change and provide effective feedback channels. Findings demonstrate that both agencies have focused on regulating harvests; I argue that in order to foster resilience of the system into the future, policy actors must reconfigure management approaches and policies towards the protection of functional seascapes. I propose two strategies in order to govern for recovery (polar bears) and resistance (bowhead whales).
  • Why did Alaska eliminate the Alaska Coastal Management Program?

    Wilson, Ryan M.; Todd, Susan; O'Donoghue, Brian P.; Speight, Jeremy S. (2018-05)
    In 1972, the federal government passed the Coastal Zone Management Act. The federal government recognized that there is a national interest in effective management of the nation's coasts. The act created a program that made it possible for states to collaborate with the federal government to manage the nation's coastal areas and resources. In July of 2011, after thirty-two years of active participation in the program, Alaska became the only eligible state or territory to choose to no longer take part in the program. This action significantly affected Alaska's ability to manage the state's coastline and resources. This research is a qualitative case study that documents the events leading up to the establishment of the Alaska Coastal Management Program, its implementation, its elimination, and the initiative regarding its possible reinstatement. The research evaluates the current form of Alaska's coastal management practices to determine if it meets Elinor Ostrom's design principles for effective common property resource management, as well as theories on decentralization/devolution, polycentric governance, and adaptability and resilience. The research concludes that Alaska's choice to eliminate the Alaska Coastal Management Program was influenced by the interests of natural resource extraction agencies and a consequence of divisive party politics. The research finds that the effect of eliminating the Alaska Coastal Management Program was that the State of Alaska took a significant step away from what science recommends as prudent ways to manage common property resources.
  • Social dimensions of invasive plant management: an Alaska case study

    Callear, Tara L.; Fix, Pete; Brinkman, Todd; Graziano, Gino (2018-05)
    Uncertainty pervades attempts to identify an efficient management response to the threat of invasive plants. Sources of uncertainty include the paucity of data, measurement errors, variable invasiveness, and unpredictable impacts of the control methods. Rather than relying on this uncertain evidence from the natural sciences, land managers are taking a more participatory approach to invasive plant management to help alleviate risk and share the responsibility of implementation of proactive control and eradication strategies. This research is intended to contribute to this process of social learning by revealing the beliefs that determine stakeholder management preferences in a case study involving an infestation of Vicia cracca (bird vetch) affecting public lands, north of the Arctic Circle, along the Dalton Highway in Alaska. Possible encroachment of this "highly invasive" species upon vulnerable areas of high conservation significance in this rapidly changing, boreal-arctic system has motivated some stakeholders to advocate an aggressive, early response aimed at eradication using herbicides. This case study applies social-psychological theory in the study of the interactions between human behavior and human outcomes. Interior Alaska stakeholders were engaged in a survey to measure support for a scenario involving the use of herbicides to control the highly-invasive species, Vicia cracca (bird vetch), which has spread north along a road corridor north of the Arctic Circle. Respondents were asked a series of questions about the "likelihood" and "acceptability" of the possible outcomes. The survey results aligned with the expectation that attitudes predict management preference, however the beliefs that influence these attitudes were more complicated than expected. The results address the feedbacks anticipated between the human outcomes and human behavior in the social template within the broader system context that are critical to management success. The purpose is to utilize the results of this specific case study to facilitate the development of ongoing research questions that are generalizable to other affected boreal-arctic ecosystems, regionally and globally.
  • Public use of local foods in the Tanana Valley: understandings of producers and low-income community members

    Garcia, Rachel Aleksandra (2012-08)
    This thesis explores factors that affect local food use in the Tanana Valley region of Alaska. Alaskan public discourses increasingly link local food production to a more sustainable and secure state and community food supply. However, current local food system development in the United States is marked by signs of socially unequal distribution of the benefits of local food. In Spring 2011, semi - structured interviews and focus groups were conducted with agricultural producers and community members affiliated with the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), and the Farmers' Market Nutrition Program (FMNP). Results show that local food use is complex and tied to livelihood and daily concerns of both producers and consumers. Producers highlighted challenges in food production, and characterized public use of local foods as limited by insufficient production. WIC employees and FMNP recipients viewed convenience and cost as important determinants of local food use. This exploratory study contributes to a more complex understanding of the local food system in the Tanana Valley through close examination of the perceptions and life experiences of human actors in this food system.
  • Toward Arctic transitions and sustainability: modeling risks and resilience across scales of governance

    Blair, Berill; Lovecraft, Amy Lauren; Kofinas, Gary P.; Eicken, Hajo; Haley, Sharman; Meek, Chanda (2017-08)
    The Arctic region has been the subject of international attention in recent years. The magnitude of impacts from global climate change, land-use change, and speculations about economic development and accessible polar shipping lanes have intensified this focus. As a result, the potential to manage complex ecological, social and political relationships in the context of changes, risks and opportunities is the focus of a large and growing body of research. This dissertation contributes to the expanding scholarship on managing Arctic social-ecological systems for resilience by answering the question: What conditions improve cross-scale learning and resilience in nested social-ecological systems experiencing rapid changes? Using the framework of social-ecological systems and the drivers of change that can transform fundamental relationships within, three studies profile the spatial and temporal dimensions of learning and risk perceptions that impact nested social systems. The first study presents a spatial and temporal analysis of scale- and level-specific processes that impact learning from risks. It draws on four cases to underscore the need for a plurality of risk assumptions in learning for resilience, and sums up essential resources needed to support key decision points for increasing resilience. Two additional studies present research conducted with northern Alaska communities and resource managers. In these studies, I analyzed the extent to which perceptions of risks scale horizontally (between same-level jurisdictions), and vertically (between levels in a dominant jurisdictional structure). These examples illustrate the need for innovative institutions to enhance cross-scale learning, and to balance global drivers of change with local socioeconomic, cultural, and ecological interests. Based on findings of the dissertation research I propose recommendations to optimize the tools and processes of complex decision making under uncertainty.
  • Community relationships with traditional forests and their effects on long-term conservation: a case study from Kaboli, Togo

    Lynch, Lauren; Todd, Susan; Gasbarro, Tony; Kokou, Kouami (2017-05)
    Despite Togo's status as a low forest cover country, remnant forest patches play an important role in conserving biodiversity and ensuring the well-being of the country's human population. Most of these remnant forest patches are communal lands managed by local family groups, and many are sacred forests, or forests that have been protected due to their role in local religious systems. In recent years, these unique social-ecological systems have been threatened due to the degradation of traditional religion. In three manuscripts, this thesis presents a case study focusing on the social and ecological role of four community forests in and around Kaboli, Togo. The first manuscript compares the ecological value and level of degradation of sacred forests and other community forests based on measurements of tree cover within historic forest boundaries, vegetation composition, biodiversity, and biomass. The second uses focus group interviews to gain an understanding of the social and cultural factors contributing to forest degradation and conservation. Finally, the third manuscript focuses on the effects of westernization on relationships between forests and people in Kaboli. Factors identified as contributing to forest degradation include rapid population growth, overly restrictive government policies, poverty, local land use conflicts, and westernization. Early western influences during the years of the slave trade contributed to the formation of relationships between forests and people in Kaboli while later effects of conservation and development efforts (including religious, political, and economic changes) eroded traditional respect for sacred forests. Communities most successful in conserving their forests are those that have sacred sites within their forests and whose cultural connections to their forests are strongest. The evidence for this is that forests containing sacred sites were significantly less degraded than otherwise similar community forests that did not contain a sacred site, with a species composition more typical of endangered dry forest ecosystems, and higher tree cover, biomass and biodiversity. Communities whose forests contained sacred sites also identified more social and cultural values of community forests than those that did not. Thus, maintaining the traditional cultural connections to these forests might be the most effective way to conserve them.
  • Factors influencing the timing and frequency of moose-vehicle collisions at urban-wildland interfaces in subarctic Alaska

    Noordeloos, Jacobus Cornelis; Mann, Daniel H.; Verbyla, David L.; Kielland, Knut; de Wit, Cary W. (2016-12)
    Wildlife-vehicle collisions concern road engineers, wildlife biologists, and the motoring public. In Alaska, moose-vehicle collisions (MVCs) are the most commonly reported type of wildlife-vehicle collisions. Each year an average of 101 MVCs were reported in the Fairbanks North Star Borough (FNSB), resulting in damages amounting to $3,000,000/yr. This thesis describes the spatial and temporal patterns of MVCs in the FNSB and uses these patterns to infer the interactions between human and moose behavior that cause them. The analytical approach used combined spatial and temporal records of MVCs collected by the Alaska Department of Transportation with spatially explicit data describing topography, land cover, traffic volume, and traffic speed. Multiple hypotheses about cause and effect were tested using computer-intensive, randomization procedures. MVCs occur most frequently during the first hours after sunset, particularly in autumn and winter. Roads in the vicinity of areas of recent wildland fires have a heightened risk of MVCs, particularly if there are moderate traffic volumes and speed limits of 90 km/h (55 mph). MVCs are also frequent on roads traversing land cover types where human population densities are low. Risk of MVCs in the FNSB is highest between 150 m and 200 m elevation. Based on these results, several mitigation measures to reduce MVCs in the FNSB are recommended, including seasonal warning signage and speed reductions in the hours after sunset. Roadside fencing designed to divert moose to designated road crossings in conjunction with infrared-triggered warning lights at these crossing points may be warranted in areas identified as hotspot locations for MVCs.
  • Landscape-scale establishment and population spread of yellow-cedar (Callitropsis nootkatensis) at a leading northern range edge

    Krapek, John P.; Verbyla, David L.; Buma, Brian; Hennon, Paul E.; D'Amore, David V. (2016-12)
    Yellow-cedar is a long-lived conifer of the North Pacific Coastal Temperate Rainforest region that is thought to be undergoing a continued natural range expansion in southeast Alaska. Yellow-cedar is locally rare in northeastern portions of the Alexander Archipelago, and the fairly homogenous climate and forest conditions across the region suggest that yellow-cedar's rarity could be due to its local migrational history rather than constraints on its growth. Yellow-cedar trees in northern range edge locations appear to be healthy, with few dead trees; additionally, yellow-cedar tend to be younger than co-dominant mountain and western hemlock trees, indicating recent establishment in existing forests. To explore yellow-cedar's migration in the region, and determine if the range is expanding into unoccupied habitat, I located 11 leading edge yellow-cedar populations near Juneau, Alaska. I used the geographic context of these populations to determine the topographic, climatic, and disturbance factors associated with range edge population establishment. I used those same landscape variables to model suitable habitat for the species at the range edge. Based on habitat modeling, yellow-cedar is currently only occupying 0.8 percent of its potential landscape niche in the Juneau study area. Tree ages indicate that populations are relatively young for the species, indicating recent migration, and that most populations established during the Little Ice Age climate period (1100 -- 1850). To determine if yellow-cedar is continuing to colonize unoccupied habitat in the region, I located 29 plots at the edges of yellow-cedar stands to measure regeneration and expansion into existing forest communities. Despite abundant suitable habitat, yellow-cedar stand expansion appears stagnant in recent decades. On average, seedlings only dispersed 4.65 m beyond stand boundaries and few seedlings reached mature heights both inside and outside of existing yellow-cedar stands. Mature, 100 --200-year-old trees were often observed abruptly at stand boundaries, indicating that most standboundaries have not moved in the past ~150 years. When observed, seedlings were most common in high light understory plant communities and moderately wet portions of the soil drainage gradient, consistent with the species' autecology in the region. Despite an overall lack of regeneration via seed, yellow-cedar is reproducing via asexual layering in high densities across stands. Layering may be one strategy this species employs to slowly infill habitat and/or persist on the landscape until conditions are more favorable for sexual reproduction. This study leads to a picture of yellow-cedar migration as punctuated, and relatively slow, in southeast Alaska. Yellow-cedar's migration history and currently limited spread at the northeastern range edge should be considered when planning for the conservation and management of this high value tree under future climate scenarios.
  • Using remote sensing to examine changes of closed-basin surface water area in Interior Alaska from 1950-2002

    Riordan, Brian Alan (2005-05)
    Over the past fifty years Alaska has experienced an increase in mean annual temperature. This warming may be causing significant changes in hydrology and permafrost dynamics. In recent decades, Native Americans and land managers have reported losses of water bodies and surface water area in interior Alaska. We conducted a study to determine the degree to which these informal observations were representative of a regional trend in surface water area loss. This study examines closed-basin water bodies in nine regions across Alaska: 1) Copper River Basin, 2) Talkeetna, 3) Tetlin National Wildlife Refuge, 4) Denali National Park, 5) Innoko Flats National Wildlife Refuge, 6) Minto Flats State Game Refuge, 7) Stevens Village, 8) Yukon Flats National Wildlife Refuge, and 9) Prudhoe Bay/Arctic Coastal Plain. The study included approximately 850,000 hectares and over 40,000 water bodies. To conduct such a large-scale study, GIS and Remote Sensing techniques were applied. Water body change detection was conducted over a fifty-year time period. A minimum of three time periods were used for each area. Imagery included black and white aerial photography (1950 -1957), color infrared aerial photography (1978 -1982), Landsat TM (1986 - 1995), and Landsat ETM+ (1999 - 2002). Based on these images, water body polygons were digitized for each time period. Area was calculated for each polygon and compared to corresponding ponds from images at later times. Of the nine regions, six showed substantial reductions in surface water area: Copper River Basin, Minto Flats, Innoko Flats, Yukon Flats, Stevens Village, and Denali National Park. The Innoko Flats and Copper River Basin regions showed the most loss at 31% and 28% respectively. There are several mechanisms possible for reductions of surface water in a warming climate including increased formation of taliks, increased soil water holding capacity, increased evapotranspiration, and terrestrialization.
  • An impact assessment of current rural Alaska village solid waste management systems: a case study

    Wilkins, William H. III; Zhang, Mingchu; Greenberg, Joshua; Mouton, Michele (2016-08)
    The purpose of this study is to examine the impacts of current and alternative solid waste management practices of two rural Alaskan villages. The EASETECH life-cycle assessment modeling tool was used to compare the current solid waste management systems for the remote villages of Kalskag and Fort Yukon across eight alternative scenarios. Annual waste generation and composition data for these two villages and data specific to processes and functions for each waste system were collected and used to modify templates within the EASETECH program to provide a life-cycle assessment for current and proposed waste management practices. The results indicate that integrated waste management practices for these remote villages may not be economically feasible or environmentally favorable. Waste management options, though limited for these remote villages, may benefit from minor system changes. These changes include transport services and burn practices that only slightly increase operating costs, but significantly reduce local social and environmental impacts. Local, accurate, and complete waste stream data could help support future management planning for the solid waste management systems of these rural villages.
  • Past, current, and future forest harvest and regeneration management in Interior Alaska boreal forest: adaptation under rapid climate change

    Morimoto, Miho; 森本未星; Juday, Glenn; Valentine, David; Huettman, Falk; Yarie, John; Barber, Valerie (2016-08)
    The Alaska boreal forest is largely ecologically intact and provides various services, but is experiencing rapid, mainly climate-driven changes, and thus adaptation is essential. Systematic forest harvest management has occurred in central Interior Alaska for about 40 years, and this period is used in this study to examine the essential elements of adaptive management: monitoring, evaluating, and adjusting. In chapter 1, I examine historical relationships between forest growth and removals in the study area. My result shows that forest harvest management has relied heavily on natural regeneration. The harvest level was much lower than the overall annual allowable cut (AAC) level in the last 40 years. However, harvest activities were concentrated in road-accessible areas and white spruce stands. In chapter 2, I evaluate whether state forest harvest units are adequately regenerated after a period of 10 to 40 years under the typical low-input management. The results indicate that post-harvest regeneration has been largely successful based on the state regeneration standard established under the Forest Practices Act and follows a similar successional pattern to that seen following fire. In chapter 3, I examine whether harvest type, site preparation method, and reforestation technique resulted in differences in forest regeneration. The results indicate that clearcutting and/or site preparation increased tree regeneration, basal area, and biomass when compared to partial harvest and/or no site preparation. Planting of white spruce may only be necessary in specific circumstances, such as years with no/low white spruce seed crop, landscapes depleted of seed trees, or when early spruce dominance of the site is desired. In chapter 4, I identify the effects of landscape and forest management predictors on post-harvest regeneration in the study area and build post-harvest regeneration scenarios under different management practices and levels of climate change. The results show that post-harvest regeneration is largely influenced by site-level environmental factors rather than management practices. Regeneration is projected to fail on many low elevation sites under the climate scenarios. As a result, forest management practices need to be adjusted specifically to the site and prepared for a climate regime shift. In chapter 5, I offer adaptive management approaches to prepare for the challenges of the future by synthesizing the knowledge and practices of the past, and the needs and challenges of today. Continued monitoring and evaluation is essential for adaptive management to be successful, particularly because of the short history of systematic forest harvest management in the study area. Some of the key forestry databases I analyzed need substantial improvement. However, this study provides the basis to build adaptive forest management for the first time in boreal Alaska, which requires adaptive approaches sooner than elsewhere due to rapid climate change now well underway.
  • Potential of Pleurotus ostreatus to remediate diesel-contaminated soil in subarctic mesocosms

    Anderson, Christin Elizabeth; Leigh, Mary Beth; Juday, Glenn; Valentine, David (2016-08)
    Pleurotus ostreatus, a gilled basidiomycete, has previously been shown to biodegrade petroleum using extracellular enzymes. However, few studies have tested petroleum biodegradation by fungi, known as mycoremediation, in cold temperatures. I conducted mesocosm studies to assess the potential from mycoremediation of diesel-contaminated soil collected from interior Alaska with a cultivated strain of P. ostreatus var. columbinus at 4 ºC, 10 ºC, and 25 ºC. In soil, both uninoculated and inoculated with P. columbinus, diesel range organics (DRO) decreased by 22-28% (p=0.455), 41-55% (p=0.236), and 91-92% (p=0.735) at the three temperatures, respectively. The differences in DRO loss between uninoculated and inoculated mesocosms at each temperature were not statistically significant, most likely due to high soil heterogeneity. However, DRO loss was greater as temperature increased, and was significantly different between the temperatures evaluated. These results indicate that temperature is a more important factor controlling DRO loss than substrate or inoculation with P. columbinus. Inoculation may enhance DRO loss at medium temperatures, but inoculation does not appear to enhance DRO loss at the highest and lowest temperatures in this study. The results also suggest that manipulating the temperature of remediation sites may be more important than inoculating with Pleurotus, and that inoculation might not be needed at sites where temperature can be increased.
  • The study of human-caribou systems in the face of change: using multiple disciplinary lenses

    Bali, Archana; Kofinas, Gary; White, Robert G.; Russell, Donald E.; McGuire, A. David (2016-05)
    Barren-ground caribou herds are part of social-ecological systems that are of critical importance to northern Indigenous Peoples of the Arctic, contributing to nutritional, cultural, and spiritual well being that are today undergoing significant changes. This dissertation uses multiple disciplinary lenses to understand the dynamics of these systems and to clarify methods for studying them. Chapter 1 focuses on a prediction of summer (June 1- August 31) mosquito activity and potential insect harassment of caribou in response to a changing climate. The Mosquito Activity Index (MAI) was based on daily ambient temperature and wind velocity obtained from the North American Regional Reanalysis dataset (NARR) from 1979 to 2009 for summer ranges of Alaska’s four Arctic herds: Western Arctic Herd (WAH), Teshekpuk Caribou Herd (TCH), Central Arctic Herd (CAH), and Porcupine Caribou Herd (PCH). Mean MAI was lowest for TCH, followed by WAH and PCH and highest for CAH. Over 31 years there was an increasing trend in MAI that affected the summer habitat of TCH and PCH, but a decreasing trend for WAH. Intra-annual patterns in MAI among herds differed in peak MAI. Chapter 2 presents a novel method of participatory videography to document the knowledge and experiences of Caribou People. Ninety-nine interviews were videoed in six Arctic communities of North America in the summer of 2008 as part of the International Polar Year. Chapter 3 presents “Voices of Caribou People,” a composite film of those interviewed, portraying the range of topics reported. Chapter 4 presents the results of an open-coding content analysis of a sample of 34 of the Voices Project interviews. Interviews described people’s rich memories of the past, aspects of their traditional knowledge and practices, the changes they have observed, the challenges they face, and what they perceive as their needs to meet present and future challenges. A key finding of the analysis is that while the research community and funding agencies are highly focused on climate change, Caribou People expressed greater concern about their social, economic, and political challenges. Caribou people noted that more studies undertaken in full partnership with caribou user communities along with community authority in decision-making are needed to sustain their human-caribou systems.

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