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Item Functional traits underlie specialist-generalist strategies in whitebark pine and limber pine(Elsevier BV, 2023-08) Ulrich, Danielle E. M.; Wasteneys, Chloe; Hoy-Skubik, Sean; Alongi, FranklinPlant species life history strategies are described by functional variation spanning an acquisitive and conservative resource use continuum. Specialist species can exhibit traits promoting one end of the continuum, while generalist species can display traits promoting both acquisitive and conservative resource use. Whitebark pine (Pinus albicaulis, PIAL) and limber pine (Pinus flexilis, PIFL) are two high-elevation pines that have similar growth and morphology, yet contrasting elevational distributions with PIAL viewed as a specialist inhabiting a narrower elevation range, and PIFL as a generalist inhabiting a broader elevation range. We compared the physiological and morphological traits of greenhouse-grown 5-year-old PIAL and PIFL. Our results suggest that PIFL’s acquisitive and conservative resource use traits contribute to its generalist strategy and ability to inhabit a greater range of elevations than PIAL. PIFL had greater acquisitive resource use traits including: high-light tolerance (greater Qsat, greater fascicle density), increased biomass allocation to photosynthetic tissue (higher needle biomass, aboveground:belowground biomass, needle:branch + stem biomass), and higher C and water uptake (greater stomatal density and size, higher C assimilation rate), as well as greater conservative resource use traits including: greater physical stress resistance (shorter height, higher stem and branch diameters, greater branch and stem diameter:length), drought tolerance (higher SWC, leaf starch proportion), and drought avoidance (earlier budburst phenology, smaller hydroscape area) than PIAL. Our results suggest that PIFL may make more efficient use of high-light loads and maximize C and water uptake when moisture is abundant during spring snowmelt before the onset of dry summer conditions. Other conservative resource use traits describing cold tolerance, heat tolerance, and drought tolerance did not differ between species, suggesting that both species exhibit traits that promote similar conservative resource use enabling their overlapping persistence at higher elevations. Comparing the physiology of PIAL and PIFL within the same environment enables us to identify physiological mechanisms that underlie species establishment and survival, and how juvenile physiology contributes to their contrasting distributions and their generalist-specialist strategies.Item An expansion of nonlethal tools for use on juvenile pallid sturgeon in the upper basin of the Missouri River(Montana State University - Bozeman, College of Letters & Science, 2020) Djokic, Matea Asahi; Chairperson, Graduate Committee: Christine Verhille; Kevin Kappenman, Joshua Heishman, Kezia Manlove and Christine Verhille were co-authors of the article, 'Investigations and implications of blood biochemistry, energetic reserves, and visual assessments to assess hatchery-reared juvenile pallid sturgeon health' which is contained within this thesis.; Kevin Kappenman, Joshua Heishman, T. Gibson Gaylord and Christine Verhille were co-authors of the article, 'An assessment of the distell fatmeter for use in juvenile pallid sturgeon (Scaphirhynchus albus)' submitted to the journal 'Transactions of the American Fisheries Society' which is contained within this thesis.Pallid sturgeon (Scaphirhynchus albus) are an endangered species endemic to the Missouri and Mississippi drainages in North America. Mitigation activities including conservation spawning and stocking programs were implemented to prevent extinction of the species. Monitoring of growth, survival, and condition are conducted annually to determine efficacy of managerial efforts to recover pallid sturgeon. My thesis aimed to establish a knowledge base of juvenile pallid sturgeon physiological bioindicators that can supplement field monitoring of growth, size, and condition measurements. Ultimately, I aimed to resolve mechanisms underlying population fluctuations (e.g. growth rate) caused by environmental changes or management actions. Fisheries managers have observed reduced growth rates of recently stocked hatchery origin pallid sturgeon (HOPS) relative to earlier cohorts. Based on high survival rates of historic stocked HOPS, some fisheries biologists hypothesize that growth rates of recent HOPS cohorts reflect compensatory density dependence in growth caused by overstocking. However, size, growth, and condition metrics commonly tracked on wild-captured sturgeon cannot assess underlying mechanisms driving trends in population growth rate. The purpose of this hatchery-based research was to explore nonlethal physiological measurements to expand the toolset available to managers to assess the status of physiological processes within HOPS that may reflect ecosystem effects on these fish. I investigated a suite of physiological bioindicators that could reflect key physiological processes (nutrition, tissue damage, and chronic stress) expected to respond to common ecosystem stressors. I determined reference intervals for 13 blood biochemical analytes on a population of healthy hatchery-reared juvenile pallid sturgeon (n = 41). Inter-individual variation in blood biochemical analytes and five additional physiological variables were analyzed to determine composite variables predictive of growth. To investigate nonlethal tools to quantify whole-body energetic reserves of juvenile pallid sturgeon, I determined best-fit predictive models to estimate whole-body energy (df = 33; R 2 = 0.40; p < 0.001) and lipid (df = 33, R 2 = 0.45, p < 0.001) content using Distell Fatmeter and mass measurements. Research presented in this thesis aims to provide a preliminary understanding of expected ranges of various physiological bioindicators and methods for nonlethally measuring these bioindicators in hatchery-reared juvenile pallid sturgeon.Item Recent and historical water use strategies of western U.S. conifers(Montana State University - Bozeman, College of Letters & Science, 2017) Clute, Timothy; Chairperson, Graduate Committee: David Roberts; Jia Hu (co-chair); Jia Hu was a co-author of the article, 'Investigating the variation in inter- and intraspecific physiological plant hydraulic traits across an elevation gradient' which is contained within this thesis.; Jia Hu was a co-author of the article, 'Historic influence of climate on conifer water status in northwestern Montana' which is contained within this thesis.Understanding the physiological traits that trees utilize to manage water use can reveal important insights into how and why they occur in their realized habitat. Among the tools to investigate these traits include measuring trees' seasonal water status, deciphering trees' rooting depth, and measuring the trees' vulnerability to cavitation. However, it is equally important to understand how complex landscape heterogeneity will affect both the inter- and intraspecific variation of these physiological traits. This thesis seeks to quantify the variation of the physiological traits used to manage water status among three common Rocky Mountain conifers; Pseudotsuga menziesii (a plastic species occurring across xeric and mesic sites), Pinus ponderosa (a xeric species), and Picea engelmannii (a mesic species), occurring across an elevation gradient. Furthermore, it aims to link tree maintenance of water status to source water, and understand how the importance of source water is reflected in the tree ring record. In the first chapter, I sought to quantify inter- and intraspecific variation of these three species by measuring diurnal and seasonal water status, seasonal water use, and xylem vulnerability to cavitation at a low elevation xeric site, composed of P. ponderosa and P. menziesii, and a high elevation mesic site, composed of P. engelmannii and P. menziesii. We found good evidence for interspecific variation in the physiological traits to manage water status at both sites. However, we did not find strong evidence for intraspecific variation in these same traits within our plastic species (P. menziesii). In the second chapter, we investigated how stable isotopes in tree rings reflected seasonal source water use as well as the atmospheric conditions the trees were growing under. At the low elevation site, we found evidence that the tree ring isotopes were likely reflecting both seasonal precipitation inputs as well as the atmospheric growing conditions. At the high elevation site, trees likely only reflected the atmospheric growing conditions and did not reflect seasonal water use.Item Temperature effects on the oxygen consumption during development of Aulocara elliotti (Thomas)(Montana State University - Bozeman, College of Agriculture, 1966) Laine, Inez IleneItem Blood sugar response of the golden hamster (Cricetus Auratus) to intraperitoneal administration of alloxan(Montana State University - Bozeman, College of Agriculture, 1952) Duiker, Vernon E.Item Effects of fluorides on Peromyscus maniculatus in Glacier National Park(Montana State University - Bozeman, College of Agriculture, 1974) Fogelsong, Mark LeroyItem Mitotic activity in the anterior pituitary of immature thyroidectomized rats(Montana State University - Bozeman, College of Agriculture, 1947) Reiquam, C. William