Theses and Dissertations at Montana State University (MSU)
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Item When and where does irrigation water originate? Leveraging stable water isotopes and synthetic aperture radar to assess the complex hydrology of a snow-dominated catchment in southwestern Montana(Montana State University - Bozeman, College of Letters & Science, 2023) Rickenbaugh, Eliza Apple; Chairperson, Graduate Committee: Eric A. Sproles; This is a manuscript style paper that includes co-authored chapters.Many agricultural regions around the world rely on water stored in mountainous snowpacks for irrigation supply. Consequently, our current and future ability to produce food is threatened by more frequent, severe, and extended snow droughts. As these snow droughts intensify, water resource managers will need more efficient and accurate methods to characterize the snowmelt cycle and forecast water availability. Focusing on a montane headwater catchment in Southwestern Montana (423 km 2 in area, between 1465 m to 3270 m in elevation), we integrate in-situ and remotely sensed data to assess the relative contributions of groundwater and the current season's snowmelt to irrigation supply for water year (WY, Oct 1 - Sep 30) 2023. To understand the period over which snow contributes to stream water in this catchment, we analyze backscatter data from Sentinel-1 Synthetic Aperture Radar (SAR). This provides approximate dates of snowmelt runoff onset at 10 m resolution every twelve days. We find that the median date of snowmelt runoff onset in WY 2023 in this catchment was April 20, six days later than the 7-year median date of snowmelt runoff onset. To assess relative contributions to streamflow we compare stable water isotope ratios (deltaH2 and deltaO18) from biweekly samples of stream water at low elevations against monthly samples of snow and groundwater. Samples range in elevation from 1,475 m to 2,555 m. We find that stream water below the highest diversion point is predominantly composed of groundwater. Results demonstrate alignment between two disparate approaches for estimating temporal trends in snowpack contribution to stream flow. While our work focuses on a catchment in Montana, the efforts and approaches used are potentially applicable globally for agricultural regions that rely on snowmelt for irrigation.Item Modeling snow water equivalent in complex mountainous terrain(Montana State University - Bozeman, College of Letters & Science, 2023) Beck, Madeline Makenzie; Chairperson, Graduate Committee: Eric A. Sproles; This is a manuscript style paper that includes co-authored chapters.The water stored in seasonal mountain snowpacks is a vital resource that approximately 20% of the world's population relies on for freshwater availability. However, accurately quantifying the amount of water stored in a snowpack, known as snow water equivalent (SWE), is difficult. The longest employed technique to quantify SWE is manual measurements. However, manual measurements of SWE are time intensive. As a result, researchers can collect relatively few point-based measurements across spatially extensive and complex regions. Automated weather stations may provide additional measurements of SWE and meteorological conditions but are expensive and difficult to maintain. Thus, reliable measurements of snow characteristics like SWE are scarce across time and space. A lack of extensive measurements causes data from few points to be extrapolated across spatially heterogeneous environments which increases uncertainty in estimates of water availability. Recent advances in satellite remote sensing allow researchers to observe snowpack dynamics across spatially continuous scales instead of relying solely on point-based measurements. However, current satellite technologies are incapable of collecting high- resolution snow data at the hillslope scale. Previous work has shown the importance of high elevation, hillslope-scale water storage reservoirs. Uncrewed aerial vehicles (UAVs) address the limitations of satellite remote sensing on the hillslope scale and are used to create high accuracy (<5 cm) models of snow depth. However, these models of snow depth provide no information on the amount of water stored without a value for snow bulk density. Thus, to capture hillslope dynamics of SWE, researchers must pair high-resolution models of snow depth with either directly measured or modeled bulk density of snow. This master's thesis integrates UAV-derived measurements of snow depth with modeled snow bulk density values to create continuous representations of hillslope-scale SWE across 9 flight dates. We found that each density modeling approach consistently underestimated SWE for the field site for each flight date except one. Further, each method of modeling snow bulk density was statistically indiscernible from each other. These findings highlight the heterogeneity of snow in mountainous terrain. In future work, bulk density models can be further parameterized to better represent site-specific values of SWE.Item Modeling saline fluid flow in subglacial ice-walled channels(Montana State University - Bozeman, College of Letters & Science, 2022) Jenson, Amy Jo; Chairperson, Graduate Committee: Scott McCallaSubglacial hydrological systems have impacts on ice dynamics as well as nutrient and sediment transport. There has been an extensive effort to understand the dynamics of subglacial drainage through numerical modeling, however these models have focused on freshwater, neglecting the consideration of brine. Saline fluid can exist in cold-based glacier systems where freshwater cannot. Therefore, there exist subglacial hydrological systems where the only fluid is brine. Understanding the routing of saline fluid is important for understanding geochemical and microbiological processes in these saline cryospheric habitats. In this thesis, I present a model of channelized drainage from a hypersaline subglacial lake and highlight the impact of saline fluid on melt rates in an ice-walled channel. The model results show that channel walls grow more quickly when fluid contains higher salt concentrations, which results in greater peak discharge and faster drainage for a fixed lake volume. This model provides a framework to assess the relative impact of brine on discharge and drainage duration.Item Daily signals in nitrate processing provide a holistic perspective on stream corridor hydrologic and biogeochemical function(Montana State University - Bozeman, College of Agriculture, 2023) Foster, Madison Jo; Chairperson, Graduate Committee: Robert A. Payn; This is a manuscript style paper that includes co-authored chapters.Understanding interactive pathways of biogeochemical reaction and water movement in stream corridors is critical given the role stream corridors play in mitigating nitrate loading from agricultural watersheds. However, few studies consider the interactive effects of nitrate loading, riparian processing, and stream ecosystem processing, which may limit abilities to predict downstream nitrate delivery. Riparian groundwater inputs and stream ecosystem processing may vary due to daily cycles in evapotranspiration or stream ecosystem primary production. Recent advances in high-frequency monitoring of stream chemistry throughout the day exhibit potential to explore both hydrologic and biogeochemical influences on nitrate attenuation. In this thesis, I explore how diel variations in stream reach nitrate processing can provide holistic perspectives on the attenuation of nitrate along stream corridors within a watershed that is heavily influenced by agricultural land use. Nitrate processing is defined as the evident changes in nitrate concentration in parcels of water as they travel along a given reach of a stream, as measured from nitrate sensors located at the head and base of ca. 0.5 km reaches. To understand controls on diel variation in nitrate processing, we measured diel processing signals in agricultural headwater reaches in Central Montana, USA spanning variable atmospheric and flow conditions from March through August in 2020-2022. Across 168 days with valid data, most signals exhibited little diel variation (n = 106) and this lack of variation occurred most frequently during cooler and shorter days. In contrast, signals with greater variation were common during longer days, warmer temperatures, and lower flows (n = 62). This seasonal shift in patterns suggests that solar radiation and stream flow are primary controls on diel nitrate processing signals in these low-order reaches. In addition to diel variation, less overall nitrate attenuation in the study reach with direct inputs of high-nitrate upland waters suggest that the degree of hydrologic connection to upland aquifers influences apparent reach nitrate processing. This work highlights how understanding the drivers of diel processing signals may lead to a more holistic understanding of how multiple interacting processes in stream corridors influence nitrate delivery to downstream ecosystems.Item Biofilm distribution in a porous medium environment emulating shallow subsurface conditions(Montana State University - Bozeman, College of Engineering, 2021) Massey, KaeLee Frances; Chairperson, Graduate Committee: Matthew Fields; Heidi J. Smith, Al B. Cunningham, Hannah Dreesbach, Luke J. McKay, Yupeng Fan, Ying Fu, Joy D. Van Nostrand, Jizhong Zhou, Katie F. Walker, Terry C. Hazen and Matthew W. Fields were co-authors of the article, 'Biofilm distribution in a porous medium reactor emulating shallow subsurface conditions' which is contained within this thesis.Microorganisms in the terrestrial subsurface play important roles in nutrient cycling and degradation of anthropogenic contaminants, functions essential to the maintenance of healthy aquifers. Microorganisms have the potential to change the geochemical properties of the shallow terrestrial subsurface, and previous studies have uncovered significant roles microorganisms can play in groundwater processes, such as biogeochemical cycling. Much of the attention given to the shallow terrestrial subsurface has been focused on the effects of contamination and how microorganisms function in these systems, with far less emphasis on understanding how hydraulic properties influence subsurface microbial ecology. To fully understand how environmental factors impact microbial community dynamics, interactions, succession, colonization, and dispersal in the shallow subsurface environment it is essential to understand the link between microbiology and hydrology. In this thesis, an up-flow packed bed reactor (PBR) was designed to emulate select field conditions (i.e., flow rate and particle size) observed at the Oak Ridge National Laboratory-Field Research Center (ORNL-FRC) to observe how environmental factors influences metabolic activity, community establishment, and cell distribution in a micropore environment. Furthermore, we developed methods to visualize the localization of active and non-active cells within the porous medium. The goals of this thesis were to 1) understand how environmental variables impact distribution and metabolic activity of microbial cells in the soil pore microenvironment at the FRC using native sediment bug trap material, 2) evaluate the hydraulic properties of the presented up-flow packed bed reactor (PBR), 3) observe how inert, non-charged particles distribute in a porous media environment, and 4) observe the biofilm distribution a microorganism isolated from the ORNL-FRC using different inoculation strategies. Overall, the data demonstrates that the presented reactor system accurately emulates field conditions and environmental factors (pH, particle size, average pore velocity) and the distribution of cells in ex situ conditions. The results of this thesis have implications for elucidating the impacts of environmental factors on metabolic activity and cell distribution in a field relevant reactor system.Item Hydraulics, hydrology, and resulting fish passage at the Huntley Diversion Nature-like Bypass(Montana State University - Bozeman, College of Engineering, 2020) Tupen, Haley Noel; Chairperson, Graduate Committee: Kathryn PlymesserDams and other instream structures have been constructed for hundreds of years in the United States for various purposes; these dams have the potential to 'disconnect' rivers and negatively impact fish upstream and downstream movement. Nature-like bypasses were created to facilitate movement around these structures and provide passage to a wide variety of morphologically different fish species. The Huntley Diversion Dam nature-like bypass was constructed in 2015 on the Yellowstone River, but its effectiveness has not yet been evaluated. This project aimed to evaluate its efficacy through monitoring and determining water stage, flow rates, channel roughness, and a detailed channel bathymetry. These data were then used in the creation of multiple two-dimensional hydraulic models encompassing the nature-like bypass channel and surrounding Yellowstone River area. Velocity results from these models were compared to species-specific swimming capabilities from literature for four Yellowstone River species. Additionally, hydraulics at the downstream bypass entrance were evaluated for disorienting hydraulic formations that might prevent fish from locating the bypass entrance. Velocity results indicate Sauger (Sander canadensis) may successfully ascend the bypass on all but five days of the modeled hydrograph and may face occasional difficulty in returning to their pre-spawning upstream habitat. Burbot (Lota lota), Channel Catfish (Ictalurus punctatus), and Smallmouth Bass (Micropterus dolomieu) are unlikely to successfully ascend the bypass for much of May, June, and July. This holds significant implications for Channel Catfish and Smallmouth Bass, both of which move upstream to spawn in the months of May and June. Hydraulics at the downstream end of the bypass indicate high attraction at high flows, but that lower flows are likely to create disorienting hydraulic characteristics at this bypass entrance and lead to low fish attraction.Item SR and U isotopes reveal interactions of surface water and groundwater along the mountain headwaters to intermountain basin transition (Hyalite Canyon and Gallatin Valley, MT)(Montana State University - Bozeman, College of Agriculture, 2018) Miller, Florence Rita; Chairperson, Graduate Committee: Stephanie A. Ewing; Stephanie A. Ewing, Robert A. Payn, James B. Paces, Sam Leuthold and Stephan Custer were co-authors of the article, 'SR and U isotopes reveal the influence of lithologic structure on stream-groundwater interaction along a mountain headwater catchment (Hyalite Canyon, MT)' submitted to the journal 'Water resources research' which is contained within this thesis.; Stephanie A. Ewing, Robert Payn, Sam Leuthold, Stephan Custer, Tom Michalek and James B. Paces were co-authors of the article, 'SR and U isotopes reveal mixing patterns of groundwater and surface water influenced by human management in an intermountain basin (Gallatin Valley, MT)' submitted to the journal 'Journal of hydrology' which is contained within this thesis.Mountainous regions of the western United States are characterized by steep, rapidly eroding mountain headwater streams transitioning to more depositional intermountain basins. The character and flux of water across these process domains is subject to projected changes in mountain headwater snowpack and agricultural and urban land use in rapidly developing intermountain basins. Here we evaluate controls on water/rock, water/substrate, and surface/groundwater interactions within Hyalite Creek and the Gallatin Valley of southwest Montana. We use solute loads and geochemical tracers (87 Sr/86 Sr, Ca/Sr, and [234U/238U]) as indicators of such interactions. Surface water, groundwater, and soil samples were collected between 2016 and 2018. Stream water in upper Hyalite Creek had low 87 Sr/86 Sr values typical of volcanic and sedimentary host rock units, and low [234 U/238 U] values consistent with shorter flow path soil, shallow aquifer or runoff water. Middle Hyalite Creek had increased [234 U/238 U] values, reflecting groundwater inflows from the Madison Group limestones. Lower Hyalite Creek had an increase in 87 Sr/86 Sr values and decrease in [234 U/238 U] values, indicated contributions from Archean gneiss fracture flow. Using mixing models, we estimate inflows from the Madison contribute ~4% during summer baseflow conditions and inflows from the Archean contribute ~2% to ~8% of streamflow during summer and winter baseflow conditions. At the mountain front, diverse Ca/Sr, 87Sr/86Sr, and [234U/238U] ratios were observed as a result of convergent flow in mountain headwaters catchments. In the intermountain basin, divergent flow at the mountain front recharges valley aquifers and combines with infiltration through soils. With distance down-valley, we observe intermediate values of Ca/Sr, 87 Sr/86 Sr, and [234 U/238 U], suggesting mixing of diverse source waters. Higher concentrations of Sr, alkalinity, and Ca/Sr and 87 Sr/86 Sr ratios consistent with soil carbonates suggest water infiltration through soil facilitated the influence of soil secondary carbonates on groundwater geochemistry. Additionally, increased water movement through soil facilitates the increase in anthropogenic loading of NO3- and Cl- in surface and groundwaters. Our results provide novel quantification of groundwater contribution to streamflow in mountain headwaters, and elucidate water quality and quantity controls from the mountain front across the intermountain basin, including valley aquifer recharge, infiltration through soils, and anthropogenic solute influxes to groundwater.Item Modeling mass balance at Robertson Glacier, Alberta, Canada 1912-2012(Montana State University - Bozeman, College of Letters & Science, 2017) Scanlon, Ryan Scott; Chairperson, Graduate Committee: Mark L. Skidmore; Jordy Hendrikx (co-chair)Glacier mass balance is important to study due to the role of glaciers in the hydrological cycle. Glacier mass balance is typically difficult to measure without numerous in situ measurements and monitoring over the course of many years. Physically based melt models are a good tool for estimating melt using temperature, solar radiation, and albedo and are used extensively in this thesis. A Degree Day (DD) model and an Enhanced Temperature Index (ETI) model are used to model mass balance for Robertson Glacier, Alberta, Canada during the period 1912-2012. The DD model only incorporates temperature, while the ETI model incorporates temperature, incoming solar radiation, and albedo. Incoming solar radiation was modeled for the period 2007-2012 and parameterized for the period 1912-2006 while temperature was measured at the regional scale and synthesized for Robertson Glacier and the snowpack thickness was modeled using PRISM. The DD and ETI models both assume a static ice mass, i.e. no flow or change in ice elevation due to mass loss over the century time period. Both models estimate a high value of annual and accumulated mean mass loss for the period 1912-2012. Sensitivity analyses of model inputs indicate that snowpack is an important factor, and it appears PRISM estimates may underrepresent beginning of the year snowpack by 220% based on a comparison of modelled to measured values on the adjacent Haig Glacier. Avalanching is not a key component of accumulation on the Haig Glacier but is a key process at Robertson Glacier, and could result in locally doubling the snowpack accumulation in avalanche zones. These factors including the resultant albedo changes with a thicker snowpack are all part of a compounding negative feedback cycle on glacier mass loss. In summary, the thesis has highlighted several potential limitations to the ETI and DD models for assessing mass loss for a small mountain glacier in the southern Canadian Rockies and provides suggestions for future modelling work in this region.Item Hydrology of a waste rock repository capping system at the Zortman Mine(Montana State University - Bozeman, College of Agriculture, 1997) Warnemuende, E. A.Item Environmental geology of the southeast margin of the Gallatin Valley, Gallatin County, Montana(Montana State University - Bozeman, College of Letters & Science, 1982) Griffith, Earl Francis
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