• The 30-year outcome of assisted regeneration treatments in a burned and salvaged Interior Alaska boreal forest

      Allaby, Andrew; Juday, Glenn; Young, Brian; Yarie, John (2015-08)
      This study contributes to the understanding of the persistence of silvicultural treatments into the stem exclusion stage of forest development in an experiment originally designed to test the effectiveness of various white spruce (Picea glauca Moench [Voss]) regeneration practices. Many studies in the North American boreal forest address the effect of silvicultural treatments on a single tree species, specifically white spruce in the great majority of cases. The experiment measured in this study provided an excellent opportunity to compare treatment effects on white spruce density and growth. The Rosie Creek Fire Tree Regeneration Installation experiment represents an operational-scale, spatially-explicit, replicated design on a single site disturbed consecutively by high-severity wildfire and clearcut salvage harvest. Three hierarchical factors, each with multiple levels, were examined: landform type, ground scarification methods, and white spruce regeneration methods. All three of the experimental factors exercised continuing influence on the patterns of white spruce regeneration and growth. The treatment effects did not attenuate over time for white spruce, and we found statistically significant effects that the original researchers could only describe as tendencies. However, relatively few studies address treatment impacts on non-target species or determine how the silvicultural treatments affect a site's overall woody biomass production. Experimental silvicultural practices targeted in this study to improve white spruce survival had profound effects on other dominant upland tree species such as quaking aspen (Populus tremuloides Michx.) and Alaska birch (Betula neoalaskana Sarg.). Interior Alaska timber species demonstrate different regeneration strategies to post-disturbance environmental conditions, especially residual organic soil layer thickness and spatial configuration of surviving potential seed sources. Effective silvicultural practices must consider each species' unique reproductive biology, and clonal sprouting as a source of aspen persistence was a particularly important example in our study. Site differences, such as we found between the slope and ridge landforms, are a key consideration for implementing effective silvicultural practices. Significant interactions between the regeneration treatments and landform types proved to be critical to meet specific reforestation objectives, particularly the different herbaceous vegetation cover types, presence/absence of aspen clonal rootstocks, and spatial configurations regarding seed sources. Managing mixed species stands, which are common in the lightly managed portions of the boreal forest, requires not only the consideration of the future crop tree, but the interacting effects of silvicultural practices on all tree species.
    • A Geobotanical Analysis Of Circumpolar Arctic Vegetation, Climate, And Substrate

      Raynolds, Martha K. (2009)
      The objective of the research presented in this dissertation was to better understand the factors controlling the present and potential future distribution of arctic vegetation. The analysis compares the Circumpolar Arctic Vegetation Map (CAVM) with circumpolar data sets of environmental characteristics. Geographical information system (GIS) software was used to overlay the CAVM with a satellite index of vegetation (normalized difference vegetation index, NDVI) and environmental factors that are most important in controlling the distribution of arctic vegetation, including summer temperature, landscape age, precipitation, snow cover, substrate chemistry (pH and salinity), landscape type, elevation, permafrost characteristics, and distance to sea. Boosted regression tree analysis was used to determine the relative importance of different environmental characteristics for different vegetation types and for different regions. Results of this research include maps, charts and tables that summarize and display the spatial characteristics of arctic vegetation. The data for arctic land surface temperature and landscape age are especially important new resources for researchers. These results are available electronically, not only as summary data, but also as GIS data layers with a spatial context (www.arcticatlas.org). The results emphasize the value and reliability of NDVI for studying arctic vegetation. The relationship between NDVI and summer temperatures across the circumpolar arctic was similar to the correlated increases in NDVI and temperature seen over the time period of satellite records. Summaries of arctic biomass based on NDVI match those based on extrapolation from ground samples. The boosted regression tree analysis described ecological niches of arctic vegetation types, demonstrating the importance of summer temperatures and landscape age in controlling the distribution of arctic vegetation. As the world continues to focus on the Arctic as an area undergoing accelerated warming due to global climate change, results presented here from spatially explicit analysis of existing arctic vegetation and environmental characteristics can be used to better understand plant distribution patterns, evaluate change in the vegetation, and calibrate models of arctic vegetation and animal habitat.
    • Anatomical And Mechanical Characteristics Of Woods Used To Manufacture Bassoons

      Levings, Carolyn K.; Barber, Valerie; Alix, Claire; Hulsey, Leroy; Keating, Richard; Rydlinski, George (2012)
      The purpose of this dissertation was three-fold -- 1) to determine if anatomical characteristics and mechanical characteristics derived from tapping (the act of striking an object lightly) can be used to more accurately describe bassoon resonant wood than the characters in use now, 2) to determine if any Alaska hardwoods can be used to construct bassoons, and 3) to produce lists of potential North American hardwoods and resonant bassoon wood characters. The bassoon resonant woods (Acer spp., Dalbergia melanoxylon, and Pyrus spp.) were compared to a known non-resonant bassoon wood (Juglans nigra). Vessel length and width, fiber length, and axial parenchyma width were measured in sectioned and macerated wood slides, along with the ratios of crystalline cellulose, lignin, pectin, and other aromatics in the cell wall. Partial frequencies created from tapping specimens on each longitudinal face were measured from melodic and peak partial spectrograms, as well as the spectrum obtained from the beginning of the sound. MANOVA and univariate ANOVA showed the resonant woods were significantly different from the non-resonant Juglans nigra using the characters measured. These characters were then used to compare two Alaska hardwoods (Alnus rubra and Betula neoalaskana) to the temperate resonant woods (Acer spp. and Pyrus spp.) and the non-resonant Juglans nigra using k-means clustering, MANOVA, and univariate ANOVA. Both Alaska hardwoods grouped with the non-resonant Juglans nigra. Lastly a list of potential North American hardwoods to be checked anatomically was compiled, as well as a list of characters that combine those used now as well as characters found in this study.
    • Applied Range Ecology Of Reindeer (Rangifer Tarandus Tarandus) On The Seward Peninsula, Alaska

      Finstad, Gregory Lawrence; Kielland, Knut; Harris, Norman (2008)
      Linking variation of the environment to animal production is key to successful range management. Ecological site descriptions (ESDs) are landscape units used by land managers for the grazing management of domestic reindeer ( Rangifer tarandus tarandus) on the Seward Peninsula, Alaska. This study investigated the appropriateness of using ESDs for the grazing management of reindeer and explored the use of alternate units to link landscape variation to animal production. ESD composition of reindeer ranges varied across the Seward Peninsula, but there was no relationship to either animal production, estimated by June calf weight and cow/calf ratios, or reindeer serum and tissue mineral concentrations. I have shown that reindeer do not graze uniformly across ESDs, but are selective, both temporally and spatially, in what they consume. Reindeer diet selection and animal production appear to be driven by temporal variation in the nutritional characteristics of individual forage species. Biomass production and seasonal nutritional characteristics of forage species were used develop a computerized mapping program for reindeer producers to identify high quality grazing areas. Production among herds was related with identified forage sources of protein in the diet. Reindeer in herds with smaller June calves consumed more catkins, stems and leaf buds of shrubs in May, presumably to compensate for lower protein reserves. Diets of reindeer and June calf weight were significantly predicted by the delta15N ‰ differential between antler core (AC) and antler periosteum (AP). Although animal production was related to landscape stratification at the species level, data showed that weather patterns affected forage nutrient concentration and foraging accessibility at a landscape level. Body weight and growth of female calves and the proportion of yearlings lactating the next summer were positively correlated with spring temperature and negatively correlated with winter severity and summer temperature. Land managers are using ESDs to monitor and assess the impact of grazing, but I have shown that landscape variation described at a multitude of scales other than ESD are linked to grazing patterns and animal production. I concluded that these alternative landscape units be integrated into reindeer range management currently being practiced on the Seward Peninsula.
    • 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.
    • Aspen coppice with coarse woody debris: a silvicultural system for interior Alaska moose browse production

      Nichols, Todd F. (2005-05)
      Browse production and use by moose (Alces alces gigas) in interior Alaska was investigated in 4 and 2-year-old quaking aspen (Populus tremuloides) coppice stands following clear-felling without removal of the mature aspen stems. Moose winter browse utilization, as related to distance from cover, coarse woody debris (CWD), and browse species composition, was quantified. Aspen terminal leaders were sampled to relate current annual growth (CAG) dry biomass (g) to leader diameter (mm). Stem density, current annual browse production, and browse use were estimated. Browse use was determined as 1) proportion of aspen stems browsed (stand scale), 2) proportion of browsed leaders per stem (stem scale), and 3) diameter-at-point-of-browsing (leader scale). Aspen sucker density ranged from 23,000-43,000 stems/ha. Terminal leader diameter was found to be a good estimator of individual stem CAG biomass. CWD did not impede moose utilization of stems. Browse use declined from mature stand edge to center (100 m). Beyond 15 m from mature stand edge browse use was low compared to that within 15 m of the stand edge. Clear-felling without removal of stems is a viable silvicultural method to reinitiate seral aspen in lieu of prescribed fire or mechanical treatments on south-facing hillsides.
    • Assessing the generalizability of study results: an outdoor recreation application

      Taylor, Stephen C. (2005-12)
      Onsite surveys of visitors have become a common method of providing information regarding recreation area visitors' norms, attitudes, motivations, management preferences, etc. Study results are often implied to be representative of a future time period for management planning purposes. One enduring method is segmenting visitors based on motivations and examining preferences for management actions/settings by group. When such a study is directly intended to guide management actions, the 'groups' must offer some degree of insight into future visitors, i.e., generalize across time. Data gathered during 2004 at the Kennecott National Historic Landmark within Wrangell- St. Elias National Park and Preserve were used to establish a hypothesized relationship between motivations and preferences for management actions. The study was replicated in 2005 to assess the generalizability of the results. A K-means cluster analysis on visitor motivations revealed five unique groups of visitors (n=206). Each group was linked with preferences for six hypothetical management actions. Utilizing generalizability theory and cluster profiling, results suggest the same five visitor types were present at Kennecott in 2005 (n=198). Furthermore, five management options exhibited evidence of generalizability across time. Although the degree of preferences varied slightly over time, opinions towards the management options did not change.
    • Assessment And Prediction Of Potentially Mineralizable Organic Nitrogen For Subarctic Alaska Soils

      Zhao, Aiqin; Zhang, Mingchu (2011)
      The objective of this study was to identify a rapid laboratory technique to predict potentially mineralizable organic N for subarctic Alaska soils. Soil samples were taken from major agricultural area of subarctic Alaska. Laboratory incubation followed by kinetic model fit was first used to select a best model to estimate potential soil N mineralization. By correlating the model estimated organic N pool sizes and different chemical extracted organic N, I then found the best chemical method to estimate soil potentially mineralizable N. Spectroscopic properties of water extractable organic matter were also determined and correlated with model estimated organic N pool sizes in order to improve the estimation of soil mineralizable N pool. Finally, the best chemical method and spectroscopic property were used in the selected best kinetic model for the prediction of soil N mineralization in field incubation. Model comparisons showed that models with fixed rate constants were better than that the ones with rate constants estimated from simulation. Among models with fixed rate constants, fixed double exponential model was best. This model differentiated active mineralizable organic N pool with a fixed rate constant of 0.693 week-1 and slow mineralizable organic N pool with a fixed rate constant of 0.051 week-1. By correlating model estimated organic N pool size and chemical extracted organic N amount, I found that the potentially mineralizable organic N size was closely correlated with hot (80 �C) water extractable organic N or 1 M NaOH hydrolysable organic N. By correlating model estimated organic N size and spectroscopic characteristics of water extractable organic matter, I found that the active mineralizable organic N pool was correlated with humification index in cold (22 �C) water extraction (R 2=0.89, p<0.05), which indicates that characterizing extracted organic matter was a useful tool to improve the estimation of soil organic N pools. In summary, potential mineralizable organic N in soils from subarctic Alaska can be estimated by hot water extractable organic matter or 1 M NaOH hydrolysable organic N, which accounted for 70% and 63% of the variation in potentially mineralizable organic N, respectively. This approach will provide fundamental insight for farmers to manage N fertilizer application in agricultural land and also provide some basic information for ecologists on predicting N release from Alaska soil that can be used for assessing the N impact on ecosystem.
    • Assessment of LiDAR and spectral techniques for high-resolution mapping of permafrost on the Yukon-Kuskokwim Delta, Alaska

      Whitley, Matthew Allen; Maio, Christopher V.; Frost, Gerald V.; Jorgenson, M. Torre (2017-05)
      The Yukon-Kuskokwim Delta (YKD) is one of the largest and most ecologically productive coastal wetland regions in the pan-Arctic. Formed by the Yukon and Kuskokwim Rivers flowing into the Bering Sea, nearly 130,000 square kilometers of delta support 23,000 Alaskan Natives living subsistence lifestyles. Permafrost on the outer delta commonly occurs on the abandoned floodplain deposits. Ground ice in the soil raises surface elevations on the order of 1-2 meters, creating plateaus on the landscape. Better drainage on the plateaus supports distinct Sphagnum-rich vegetation, which in turn protects the permafrost from rising air temperatures with low thermal conductivity during the summer. This ecosystem-protected permafrost is thus vulnerable to disturbances from rising air temperatures, vegetation mortality, and inland storm surges, which have been known to flood up to 37 km inland. This thesis assesses several novel techniques to map permafrost distribution at high-resolution on the YKD. Accurate baseline maps of permafrost extent are critical for a variety of applications, including long-term monitoring. As air and ground temperatures rise across the Arctic, monitoring landscape change is important for understanding permafrost degradation processes (e.g. thermokarst) and greenhouse gas dynamics from the local to global scales. This thesis separately explored the value of Light Detection And Ranging (LiDAR) and spectral datasets as tools to map permafrost at a high spatial resolution. Furthermore, this thesis sought to automate these processes, with the vision of high-resolution mapping over large spatial extents. Fieldwork was conducted in July 2016 to both parameterize and then validate the mapping efforts. The LiDAR mapping extent assessed a 135 km² area (~15% permafrost cover), and the spectral mapping extent assessed an 8 km² area (~20% permafrost cover). For the LiDAR dataset, the use of a simple elevation threshold informed by field ground truth values provided a permafrost map with 94.9% accuracy. This simple approach was possible because of the extremely flat terrain. For the spectral datasets, an ad-hoc masking technique was developed using a combination of texture analysis, principal component analysis, and morphological filtering. Two contrasting workflows were evaluated with fully-automated and semi-automated methods with mixed results. The highest mapping accuracy was 89.4% and the lowest was 79.1%, though the error of omission in mapping the permafrost remained high (7.02 - 59.7%) for most analyses. The spectral mapping algorithms did not replicate well across different high-resolution images, raising questions about the viability of using spectral methods alone to track thermokarst and landscape change over time. However, incorporating the spectral methods explored in this analysis with other datasets (e.g. LiDAR) has the potential to increase mapping accuracies. Both the methods and the results of this thesis enhance permafrost mapping efforts on the YKD, and provide a good first step to monitoring landscape change in the region.
    • Birch, Berries, And The Boreal Forest: Activities And Impacts Of Harvesting Non-Timber Forest Products In Interior Alaska

      Maher, Kimberley Anne C.; Juday, Glenn P.; Barber, Valerie; Gerlach, S. Craig; Watso, Annette (2013)
      Harvesting wild berries, firewood, and other non-timber forest products (NTFPs) from the boreal forest in Interior Alaska is a common activity amongst local residents. NTFPs are harvested for personal use, subsistence, and commercial purposes. While these activities contribute to informal household economies and livelihoods, harvest of NTFPs are not well documented in Alaska. Availability of these ecosystem services may be altered under changing management and climate regimes. This interdisciplinary dissertation takes a look at the activities and impacts of current NTFP harvesting practices. Survey results from a forest use survey provide insight into harvest activity in the Tanana Valley. Wild blueberries (38.5% of households with mean harvested amount of 7.7 quarts) and firewood (25.0% of households with a mean harvest amount of 4.7 cords) were reported harvested with greatest frequency, and harvesting activities were mostly concentrated around larger population centers. Interviews were conducted with personal use and subsistence NTFP harvesters from Interior Alaska. Participants enjoy harvesting from the forest, and that the importance of harvesting is a combination of both the intangible benefits from the activity and the tangible harvested items. Harvested NTFPs were seen as high-quality products that were otherwise unavailable or inaccessible. Birch syrup is a commercially available NTFP produced in Alaska by a small number of companies. Similar to maple syrup, producing birch syrup is a labor intensive process with marginal profits. Interviews were conducted with workers in the Alaskan birch syrup industry, who reported that they were seeking an alternative to the traditional employment. The effects from mechanical damage from tapping for spring sap on birch's vigor are of concern to birch syrup producers and natural resource managers. This study compared the annual increment growth of Alaskan birch trees, Betula neoalaskana, between tapped and untapped trees. No significant difference was detected from tapping, but annual variability in growth was strongly significant. A temperature index accounted for nearly two-thirds of the annual variability. Pairing this index with two climate scenarios, birch growth was extended out through the 21st century. As temperatures rise, birch in Interior Alaska are projected to face a critical threshold, which may limit or extinguish their ability to sustain growth and yield a sustainable sap resource. Integrating the survey, interview, and dendroclimatological data provides a richer picture of how NTFP harvesters actively use the forest and about the benefits derived. These findings can assist resource managers in balancing these needs with those of other forest uses on public land.
    • Carbon Cycling In Three Mature Black Spruce ( Picea Mariana [Mill.] B.S.P.) Forests In Interior Alaska

      Vogel, Jason Gene; Valentine, David (2004)
      Climate warming in high latitudes is expected to alter the carbon cycle of the boreal forest. Warming will likely increase the rate of organic matter decomposition and microbial respiration. Faster organic matter decomposition should increase plant available nutrients and stimulate plant growth. I examined these predicted relationships between C cycle components in three similar black spruce forests (Picea mariana [Mill] B.S.P) near Fairbanks, Alaska, that differed in soil environment and in-situ decomposition. As predicted, greater in-situ decomposition rates corresponded to greater microbial respiration and black spruce aboveground growth. However root and soil respiration were both greater at the site where decomposition was slowest, indicating greater C allocation to root processes with slower decomposition. It is unclear what environmental factor controls spruce allocation. Low temperature or moisture could cause spruce to increase belowground allocation because slower decomposition leads to low N availability, but foliar N concentration was similar across sites and root N concentration greater at the slow decomposition site. The foliar isotopic composition of 13C indicated soil moisture was lower at the site with greater root and soil respiration. From a literature review of mature black spruce forests, it appears drier (e.g. Alaska) regions of the boreal forest have greater soil respiration because of greater black spruce C allocation belowground. Organic matter characteristics identified with pyrolysis gas chromatography-mass spectrometry correlated with microbial processes, but organic matter chemistry less influenced C and N mineralization than did temperature. Also, differences among sites in C and net N mineralization rates were few and difficult to explain from soil characteristics. Warming had a greater influence on C and N mineralization than the mediatory effect of soil organic matter chemistry. In this study, spruce root C allocation varied more among the three stands than other ecosystem components of C cycling. Spruce root growth most affected the annual C balance by controlling forest floor C accumulation, which was remarkably sensitive to root severing. Predicting the response of black spruce to climate change will require an understanding of how spruce C allocation responds to available moisture and soil temperature.
    • Caribou migration, subsistence hunting, and user group conflicts in northwest Alaska: a traditional knowledge perspective

      Halas, Gabriela; Kofinas, Gary; Fix, Peter; Joly, Kyle (2015-08)
      Alaska Natives of northwest Alaska are highly dependent on barren-ground caribou (Rangifer tarandus) for meeting their nutritional and cultural needs. The Alaska Native village of Noatak borders the Noatak National Preserve (NNP), an area historically and presently used by Iñupiaq for subsistence caribou hunting and other traditional activities. Interactions between local and non-local caribou hunters were analyzed through the lens of common pool resource theory, which I linked to traditional Iñupiaq management of access and use of resources. This study examined changes in caribou migration and its effect on local caribou hunting success, which have been perceived to be the result of the interaction with non-local hunters and commercial aircraft operators transporting non-locals. Past research, decades old at this point, was undertaken prior to some regulations in place today, such as zoned use areas. To understand the implications of these changes, I documented the perceptions of local hunters by drawing on their traditional ecological knowledge (TEK), using a mixed methods approach to capture information on caribou ecology and human-caribou interactions. Mixed methods included a survey of active hunters, semi-structured participatory mapping interviews with local caribou experts of Noatak, key informant interviews, and participatory observation. Local hunters reported that caribou migration has changed, and there has been a decrease in the population of the region's caribou herd, the Western Arctic Herd (WAH). Hunters also reported that caribou hunting has changed substantially in the last five years, with fewer caribou harvested and hunters adapting to accommodate caribou migration shifts. Local hunters ranked aircraft and non-locals hunters as having the greatest negative impact to caribou migration and local hunting, followed by predation, climate change and habitat change. Noatak hunters perceived that their harvest of caribou is most impacted by non-local activity in the Noatak region. As well, local hunters reported that aircraft are a greater disturbance than on-the-ground non-local hunters. Participatory mapping revealed that use-areas are shared by local and non-local users along the Noatak River corridor, including both inside and outside zoned use areas. Suggestions by respondents for improved caribou management and conflicts with non-locals ranged from reducing non-local activity, working together with non-locals and aircraft operators, improving economic development for Noatak, and teaching youth of the village traditional hunting practices. Findings of this research demonstrate that local hunters have a rich, localized knowledge of human-caribou systems, which can contribute further to understanding of caribou-human interactions and in turn help to inform wildlife management decision-making.
    • Changing strategies in Seward Peninsula reindeer (Rangifer tarandus tarandus) management

      Oleson, Heather J. (2005-12)
      Reindeer (Rangifer tarandus tarandus) management techniques have changed since the founding of the reindeer industry on the Seward Peninsula in 1891. From 1891-1915, herds were small and management was intensive. Between 1915 and 1944, community herds and joint stock companies were formed. Herd management was extensive and herds were large and relatively free roaming. A period of re-privatization followed from 1944 to 1960, during which a limited number of moderately stocked ranges were established. The era after 1960 saw the introduction of several new forms of technology, some of which became catalysts for broad changes in reindeer management. Snow machines (c. 1960s), helicopters (c. 1970s), radio telemetry (c. 1980s), and Internet use became an integral part of how reindeer were managed. Most recently, satellite telemetry and online mapping have been developed as herd management tools. Combining telemetry, mapping programs, and the Internet allows herders to monitor range use, herd movement, and whether their animals need to be moved to refuge areas to prevent mixing with caribou. Equipped with this knowledge, herders can more effectively use ATV's and aircraft to manage their herds.
    • Characterization and delineation of caribou habitat on Unimak Island using remote sensing techniques

      Atkinson, Brian M.; Harris, Norman R.; Finstad, Greg L.; Verbyla, David L. (2014-08)
      The assessment of herbivore habitat quality is traditionally based on quantifying the forages available to the animal across their home range through ground-based techniques. While these methods are highly accurate, they can be time-consuming and highly expensive, especially for herbivores that occupy vast spatial landscapes. The Unimak Island caribou herd has been decreasing in the last decade at rates that have prompted discussion of management intervention. Frequent inclement weather in this region of Alaska has provided for little opportunity to study the caribou forage habitat on Unimak Island. The overall objectives of this study were two-fold 1) to assess the feasibility of using high-resolution color and near-infrared aerial imagery to map the forage distribution of caribou habitat on Unimak Island and 2) to assess the use of a new high-resolution multispectral satellite imagery platform, RapidEye, and use of the "red-edge" spectral band on vegetation classification accuracy. Maximum likelihood classification algorithms were used to create land cover maps in aerial and satellite imagery. Accuracy assessments and transformed divergence values were produced to assess vegetative spectral information and classification accuracy. By using RapidEye and aerial digital imagery in a hierarchical supervised classification technique, we were able to produce a high resolution land cover map of Unimak Island. We obtained overall accuracy rates of 71.4 percent which are comparable to other land cover maps using RapidEye imagery. The "red-edge" spectral band included in the RapidEye imagery provides additional spectral information that allows for a more accurate overall classification, raising overall accuracy 5.2 percent.
    • Clay mineralogy and soil formation in moist acidic tundra and moist nonacidic tundra of northern Sagwon HLS, Alaska

      Borden, Patrick William (2006-05)
      Clay mineralogy, physical and chemical characteristics were studied in three sites of moist acidic tundra (MAT) and three sites in moist nonacidic tundra (MNT) in the Northern Sagwon Hills, Alaska. The major similarities found in physical characteristics between MAT and MNT were color, field texture and consistence. Dissimilarities were in the depth, boundary and thickness of the horizons as well as soil structure. The major similarities found in chemical characteristics across MAT and MNT were in % carbon and nitrogen, ammonium phosphorus, iron and aluminum contents. The major dissimilarities were in pH, cation exchange capacity, nitrate and base saturation. Upper horizon pH in MAT was lower than MNT while deeper horizons had similar pH's. The mean average annual soil temperature was around -5°C in both MAT and MNT. The most common clay minerals found were illite, vermiculite and kaolinite. Kaolinite was determined to be detrital, not neoformed. Vermiculite from weathered illite was determined to be the most significant weathering product. The study also determined that the proportion of vermiculite to illite was higher in MAT and the illite to vermiculite proportion was higher in MNT. This finding showed that soil acidity does affect weathering reactions despite the low soil temperature.
    • 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.
    • 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).
    • Conditions For Effective Use Of Community Sustainability Indicators And Adaptive Learning

      Powell, James E.; Kofinas, Gary (2012)
      As the number of community sustainability indicator programs (SIPs) increases in many regions of the world, including in the United States, questions continue to arise regarding how decision makers can use sustainability indicators (SIs) to contribute in a meaningful way to their efforts to build resilient and sustainable communities. Through an analysis of the sustainability activities in sample cities from across the U.S. and a case study of one city that adopted SIs but has yet to implement them, this study seeks to uncover the conditions for effective SI implementation and use. The study began with a review of the literature on communities' sustainability efforts and the historical roots of sustainability and resilience theory leading up to today's sustainability indicator projects. A heuristic model for adaptive learning is presented to illustrate the relationships among sustainability, resilience, and administrative concepts, including the goals and domains of sustainability indicators. The study's data collection and analysis began with an Internet-based investigation of 200 U.S. cities. A five-tiered system was devised to categorize findings regarding sustainability patterns and trends in studied cities, ranging from an absence of sustainability activities through fully implemented sustainability indicators. The second phase of data collection employed an electronic survey completed by informants from a 38-city sample of the 200 investigated cities, followed by phone interviews with informants from cities that ranked high for developed sustainability programs. A case study using focus group research was then conducted of one small U.S. city, Juneau, Alaska, where local government adopted sustainability indicators in the 1990s but fell short of implementing them. Most cities in the U.S. have not developed sustainability indicator projects, and, among those that have, few have been able to implement them fully. Among highly ranked cities with sustainability indicators, several approaches, including innovative organizational structures and adaptive learning processes, were found to be present. Recommendations for incorporating such innovations and for grounding sustainability indicator projects in sustainability science, resilience thinking, and public administration theory are offered to help ensure sustainability indicators become fully operational in Juneau, as well as in other communities seeking to establish successful sustainability indicator programs.
    • 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.
    • A dendroclimatological study of long-term growth patterns of yellow-cedar trees in Southeast Alaska

      Sink, Scott E. (2006-08)
      Yellow-cedar is a very long-lived, commercially important tree species found along the coasts of Southeast Alaska and also in small populations in Prince William Sound. However, this is the first study of the tree's annual ring growth patterns in the region. Tree cores were collected from over 400 trees across a large latitudinal gradient and cross-dated using standard dendrochronological techniques. Radial tree-ring growth was measured and compared to reconstructed weather station data to gain a better understanding of the climatic conditions favoring yellow-cedar growth. We found consistent, significant positive correlations between ring widths and mean monthly temperatures in August, previous January, and previous December, and negative relationships with May and December precipitation. Climate indices we created using these variables explain approximately 25% of growth variability in five distinct yellow-cedar populations. Long-term growth patterns in tree populations going back three centuries were similar across all sites, specifically the sustained below mean growth during the 1800s. Yellow-cedar at the northern limits of its distribution shows a common growth signal which may indicate the influence of larger pressure anomalies, such as EI Nino-Southern Oscillation (ENSO), on the climate factors affecting the trees.