• Bringing broader impacts to the community via university K-12 partnerships: growth in and seed quality of Betula neoalaskana Sargent

      Kanie, Sayako; Dawe, Janice C.; Karlsson, Meriam; Yeats, Scott (2020-05)
      Betula neoalaskana Sargent is the most abundant birch species in Alaska. All parts of the tree can be used in creating timber and non-timber products, and birch stands provide high-value ecosystem services for ecotourism and outdoor recreational purposes. For these reasons, the OneTree Alaska program of the University of Alaska Fairbanks uses Interior Alaska white birch as the centerpiece of its work. This M.S. thesis is a contribution to OneTree Alaska's goal of raising the public's understanding of the effects of Interior Alaska's lengthening growing season on the growth and reproduction of the local birch resource. Specifically, the thesis relates to the growth and reproduction of the offspring of the original "one trees" harvested on Nenana Ridge in October 2009. The saplings have been growing in the Generation OneTree Research Plot in the T-field, north of the Smith Lake on the University of Alaska Fairbanks campus, since June 2011 and represent half-sibling families reared from the seed of 8 maternal trees. As seedlings, they were reared for growing seasons of variable length, both by students at the Watershed Charter School of the Fairbanks North Star Borough and by OneTree personnel in a University of Alaska Fairbanks growth chamber. Prior to this study, end of year measurements had been taken of the young trees in the T-field for all but one year and established that the length of the first growing season persistently affected the number of stems and the diameter at breast height (DBH) of the main stems. New findings in this thesis show that the elevation difference among trees impacts the number of infructescences and germination rates but not the number of male catkins. At least for the 2018 seed crop, seeds from trees planted at higher elevations in the T-field showed higher germination rates than those planted at lower elevations, while they produce fewer infructescences at up slope. Other findings demonstrate that sibling family does not have an effect on either vegetative or reproductive growth. Instead, the length of the first growing season provides for a diversity of canopy shapes across sibling families. The most significant finding is the effect of elevation on female reproductive growth: It suggests a number of next steps, tools, and analysis to better understand environmental variables that work alongside elevation in determining growth and reproductive success. Soil moisture and pH (H2O), Carbon/Nitrogen ratio, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to determine micronutrient composition, sensors to capture wind speed/direction and solar radiation, photosynthetic traits, and chlorophyll concentration measurements could all be valuable in further elucidating the hypotheses being advanced by this research regarding the interactions between changing environment and reproduction.
    • 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.
    • Design of a multichannel outdoor data logger for precise temperature measurements

      Dolgikh, Kirill; Raskovic, Dejan; Romanovsky, Vladimir; Thorsen, Denise (2018-12)
      In this thesis, we present the prototype of a multichannel data logger (the Logger) for precise temperature measurements. Its intended application is to take soil (permafrost) temperature measurements with a thermistor probe or thermistor string. However, its hardware and firmware architectures are quite flexible, so it can be used in other applications. The Logger has 16 channels. In addition to the internal memory, it supports microSD-cards of up to 2 GB, which allows it to store up to 41.9 million measurements for each channel. The Logger's estimated battery life is 8 years when making measurements once per hour. It has a radio transmitter, which will allow it to download data wirelessly and potentially participate in a wireless sensor network once the appropriate firmware is developed. Currently, only the communication protocol with the radio is implemented, while the radio-to-radio protocol is under development. The Logger is small - only 6 x 1 x 1 inches and the final product will be even smaller. Components are rated down to -40° C and the Logger successfully passed testing at -30° C. After the extensive testing to ensure performance it has been shown that the Logger outperforms the Campbell Scientific, Inc. CR1000 logger and exceeds the design requirements. Measured temperature resolution of the Logger is below 2.5 mK in the entire temperature range. The Logger's equivalent temperature accuracy, which was determined using a known resistive input, is below 10 mK within -25° C to 40° C and below 20 mK elsewhere. The developed calibration technique provides the equivalent accuracy below 0.3 mK within -40° C to 40° C. To provide an accuracy of ±0.01° C when making temperature measurements with thermistors, the Logger should be calibrated against a thermometer that has been calibrated as a secondary standard, which will be done in the future.
    • Effects of climate variability and fishing on gadid-crustacean interactions in subarctic ecosystems

      Marcello, Laurinda; Mueter, Franz; Eckert, Ginny; Kruse, Gordon (2011-12)
      Snow crab (Chionoecetes opilio) are a vital economic and biotic resource to many subarctic ecosystems. Their abundance varies greatly, but what causes large changes in production and early life survival is unknown. My overall goal is to improve our understanding of snow crab population dynamics during early life history stages. Chapter 1 provides background information on subarctic ecosystems, addresses possible mechanisms of population control and potential drivers of variability, describes snow crab life history, and reviews recent population trends in snow crab and their major cod predators. Chapter 2 details a regression study examining the effects of snow crab spawning stock biomass, environmental conditions, and Pacific cod (Gadus macrocephalus) or Atlantic cod (Gadus morhua) biomass on snow crab recruitment. This study compares three ecosystems: the eastern Bering Sea, the Newfoundland-Labrador Shelf, and the southern Gulf of St. Lawrence. Cold ocean conditions during early life history were associated with increased snow crab recruitment or recruitment indices in all three ecosystems. However, there was no consistent observed effect of spawning stock biomass or gadid predation on subsequent recruitment. The dominant role of environmental conditions in driving snow crab recruitment highlights the importance of an ecosystem-based management approach for these stocks.
    • The molecular basis of aerobic metabolic remodeling in threespine stickleback in response to cold acclimation

      Orczewska, Julieanna Inez (2011-05)
      Increases in mitochondrial density during cold acclimation have been documented in many fish species, however the mechanism regulating this process is not understood. The present study sought to characterize metabolic changes in response to cold acclimation and identify how these changes are regulated in oxidative muscle, glycolytic muscle and liver tissue of threespine stickleback, Gasterosteus aculeatus. Fish were warm (20°C) or cold (8°C) acclimated for 9 weeks and harvested during acclimation. Mitochondrial volume density was quantified using transmission electron microscopy and aerobic metabolic capacity assessed by measuring the maximal activity of citrate synthase and cytochrome c oxidase. The molecular mechanism mediating changes in aerobic metabolic capacity were assessed by quantifying transcript levels of aerobic metabolic genes and known regulators of mammalian mitochondrial biogenesis using quantitative real-time PCR. Our results indicate that while the maximal activity of aerobic metabolic enzymes increased in all tissues, mitochondrial biogenesis only occurred in oxidative muscle. Our results also suggest that the time course of metabolic remodeling is tissue specific. Lastly, we identified differences in the magnitude and timing of transcriptional and co-transcriptional activators driving metabolic remodeling between each tissue. These results suggest aerobic metabolic remodeling may be triggered by different stimuli in different tissues.
    • Morphological and phenological responses of butterflies to seasonal temperature increase in Alaska

      Daly, Kathryn Margaret; Breed, Greg A.; Sikes, Derek S.; Mann, Daniel H. (2018-12)
      Climate is changing rapidly at high latitudes, and the responses of insects provide early indications of the impacts these changes have on biota. Butterflies (Lepidoptera: Papilionoidea) are among the best-known Subarctic and Arctic insects, and research in Greenland has revealed significant declines in butterfly body sizes along with advances in the timing of their first flights in spring. These changes are ecologically significant because smaller body sizes can lead to reduced fecundity in butterflies, and earlier adult emergence can have detrimental effects across trophic levels because Lepidoptera are an important food resource for birds and mammals. The primary goal of this thesis is to expand the geographical scope of previous studies of butterfly responses to high-latitude warming by testing whether Alaskan butterflies have exhibited morphological (Chapter 1) and/or phenological (Chapter 2) changes in response to rising temperatures. The morphological parameter studied here is forewing length, and the phenological parameter the timing of the first-observed flight of the year. Results show that the wings of two out of three butterfly species studied from Alaska's North Slope and Seward Peninsula decreased as seasonal (spring and summer) temperatures rose between 1971 and 1995. For every 1° C increase in average seasonal temperatures, wingspans decreased by up to 1.4 millimeters in Alaska. This compares to decreases of up to 0.65 millimeters observed in Greenland. One Alaskan species, Colias hecla Lefebvre 1836, did not show significant change in its wing lengths, although it did exhibit significant decreases in Greenland. Differences in life-history traits among species appear to result in divergent responses in Alaskan butterflies, with Boloria freija (Thunberg, 1791), which overwinters as late-instar larvae, showing the greatest decrease in wing length compared to Boloria chariclea (Edwards, 1883) which overwinters as early-instar larvae. From the start of the collection record in 1966 onward, collection and observational records from Interior Alaska reveal an average phenological advancement of 1 to 5 days/decade in 13 spring-emerging butterfly species. The morphological and phenological changes found in some species of Alaskan butterflies correlate with recent climate change, though the effects differed among species. The eco-physiological responses to climate change observed here for butterflies are likely to be shared by other insect species living at high latitudes.