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Item Cultivation and visualization of a methanogen of the phylum Thermoproteota(Springer Science and Business Media LLC, 2024-07) Kohtz, Anthony J.; Petrosian, Nikolai; Krukenberg, Viola; Jay, Zackary J.; Pihofer, Martin; Hatzenpichler, RolandMethane is the second most abundant climate-active gas, and understanding its sources and sinks is an important endeavour in microbiology, biogeochemistry, and climate sciences1,2. For decades, it was thought that methanogenesis, the ability to conserve energy coupled to methane production, was taxonomically restricted to a metabolically specialized group of archaea, the Euryarchaeota1. The discovery of marker genes for anaerobic alkane cycling in metagenome-assembled genomes obtained from diverse habitats has led to the hypothesis that archaeal lineages outside the Euryarchaeota are also involved in methanogenesis3,4,5,6. Here we cultured Candidatus Methanosuratincola verstraetei strain LCB70, a member of the archaeal class Methanomethylicia (formerly Verstraetearchaeota) within the phylum Thermoproteota, from a terrestrial hot spring. Growth experiments combined with activity assays, stable isotope tracing, and genomic and transcriptomic analyses demonstrated that this thermophilic archaeon grows by means of methyl-reducing hydrogenotrophic methanogenesis. Cryo-electron tomography revealed that Ca. M. verstraetei are coccoid cells with archaella and chemoreceptor arrays, and that they can form intercellular bridges connecting two to three cells with continuous cytoplasm and S-layer. The wide environmental distribution of Ca. M. verstraetei suggests that they might play important and hitherto overlooked roles in carbon cycling within diverse anoxic habitats.Item Exploring canyons beneath Devon Ice Cap for sub-glacial drainage using radar and thermodynamic modeling(Cambridge University Press, 2024-09) Pierce, Chris; Skidmore, Mark; Beem, Lucas; Blankenship, Don; Adams, Ed; Gerekos, ChristopherSub-glacial canyon features up to 580 m deep between flat terraces were identified beneath Devon Ice Cap during a 2023 radar echo sounding (RES) survey. The largest canyon connects a hypothesized brine network near the Devon Ice Cap summit with the marine-terminating Sverdrup outlet glacier. This canyon represents a probable drainage route for the hypothesized water system. Radar bed reflectivity is consistently 30 dB lower along the canyon floor than on the terraces, contradicting the signature expected for sub-glacial water. We compare these data with backscattering simulations to demonstrate that the reflectivity pattern may be topographically induced. Our simulated results indicated a 10 m wide canal-like water feature is unlikely along the canyon floor, but smaller features may be difficult to detect via RES. We calculated basal temperature profiles using a 2D finite difference method and found the floor may be up to 18°C warmer than the terraces. However, temperatures remain below the pressure melting point, and there is limited evidence that the canyon floor supports a connected drainage system between the DIC summit and Sverdrup Glacier. The terrain beneath Devon Ice Cap demonstrates limitations for RES. Future studies should evaluate additional correction methods near complex terrain, such as RES simulation as we demonstrate here.Item The Role of Teacher Education in Improving Digital Literacy: A Pre-Service Teacher Case Study(New Prairie Press, 2024-10) Taheri, Rana; Pennington, SarahTechnology is crucial for teaching and learning in the 21st century. However, many pre-service teachers (PSTs) feel unprepared to utilize digital literacy (DL) in their future classes. This study explored PST’s perceptions of their DL knowledge and the perceived impact of their teacher education programs through a qualitative bounded case study method. Participants for this study were three PSTs engaged in a technology integration course at a land grant university in the northwestern US. Participants engaged in recorded one-on-one semi-structured interviews to learn about their perceptions and readiness for DL. The findings indicate that while PSTs were aware of DL, they lacked confidence in their ability to teach it. The study identified four critical themes related to the PSTs' perspectives on DL: concerns, challenges, advantages, and future decisions. The prioritization of DL training in teacher education programs and the reconsideration of engaging technology-related courses by universities and policymakers are recommended.Item Cost, Advocacy, and a Mechanism for Transformation: The Proposed Power of Open Access Funds(American Library Association, 2024-01) Sterman, Leila BelleAs paid open access becomes a mainstream academic practice, stakeholders must evaluate their role in the system. While open access advocates develop new ways to support the publication process and funding structure, commercial publishers continue to pivot to maintain their profit, relevance, and power in the publication system. This article provides the details of Montana State University’s Open Access Author Fund as an evaluation of the service and its impact on the local publishing ecosystem. As stewards of publicly funded knowledge, it is essential to critically analyze each new publishing route before adopting and supporting it. Especially when models claim to transform the system, librarians need to understand how an action changes the system, for whom, and at what cost.Item Short Communication: artificially reared ewes cannot be distinguished from natural reared ewes based on observed maternal behavior or lamb weaning weights(Oxford University Press, 2024-09) Posbergh, Christian J.; Miles, Asha M.; Pettifor, Natasha L.; Thonney, Michael L.Artificially rearing lambs is an important component of United States sheep production as some flocks select for increasing litter size to boost productivity. However, there is a conception among shepherds that artificially reared ewe lambs will ultimately result in poor mothers since they were not naturally raised. The objective of this study was to determine if differences in maternal behavior could be detected between ewes raised artificially and those raised naturally and if dam rearing type had an impact on lamb growth performance. Forty-eight ewes were enrolled comprised of 4 equal sized groups: artificially reared primiparous, naturally reared primiparous, artificially reared multi-parous, and naturally reared multi-parous. Ewes were observed using remote cameras to record maternal behaviors toward the lambs during and shortly after parturition. Behavior of 29 ewes during the first hour after parturition was analyzed. Independent multivariable regression models were evaluated for: proportion of time spent grooming, proportion of time spent helping the lambs nurse, number of helpful bouts, and the number of negative bouts. No statistically significant difference (P < 0.05) was detected between artificially reared and naturally reared ewes for the proportion of time spent grooming and the proportion of time spent helping the lambs nurse. Historical flock data were utilized to evaluate lamb growth between artificially and naturally reared ewes. No detrimental associations between artificially reared ewes and lamb weaning weights were observed. This study shows that artificially reared ewes are no different in terms of mothering behaviors and may be used as potential replacement candidates.Item Green Infrastructure Microbial Community Response to Simulated Pulse Precipitation Events in the Semi-Arid Western United States(MDPI AG, 2024-07) Hastings, Yvette D.; Smith, Rose M.; Mann, Kyra A.; Brewer, Simon; Goel, Ramesh; Jack Hinners, Sarah; Follstad Shah, JenniferProcesses driving nutrient retention in stormwater green infrastructure (SGI) are not well quantified in water-limited biomes. We examined the role of plant diversity and physiochemistry as drivers of microbial community physiology and soil N dynamics post precipitation pulses in a semi-arid region experiencing drought. We conducted our study in bioswales receiving experimental water additions and a montane meadow intercepting natural rainfall. Pulses of water generally elevated soil moisture and pH, stimulated ecoenzyme activity (EEA), and increased the concentration of organic matter, proteins, and N pools in both bioswale and meadow soils. Microbial community growth was static, and N assimilation into biomass was limited across pulse events. Unvegetated plots had greater soil moisture than vegetated plots at the bioswale site, yet we detected no clear effect of plant diversity on microbial C:N ratios, EEAs, organic matter content, and N pools. Differences in soil N concentrations in bioswales and the meadow were most directly correlated to changes in organic matter content mediated by ecoenzyme expression and the balance of C, N, and P resources available to microbial communities. Our results add to growing evidence that SGI ecological function is largely comparable to neighboring natural vegetated systems, particularly when soil media and water availability are similar.Item 'Hypertemporal' remote sensing of plant function: a comparison of phenocam and geostationary operational environmental satellite NDVI data products(Montana State University - Bozeman, College of Agriculture, 2019) Douglas, James Thomas; Chairperson, Graduate Committee: Paul C. StoyOngoing climate warming is changing the seasonality of plant canopy function, but common approaches to explore these changes via polar-orbiting satellites often miss rapid canopy transitions due to infrequent observations. I explored the ability of satellites designed for studying weather systems, namely The Geostationary Operational Environmental Satellite (GOES), to track plant canopy status on time scales of minutes. With new capabilities to remotely sense in the infrared, the GOES weather satellites now have the capability to detect photosynthetic activity. Satellite observations of the normalized difference vegetation index (NDVI) are compared against near-surface phenological camera ("PhenoCam") observations from the National Ecological Observation Network (NEON, Inc.) at six sites every 15 minutes for one week in April 2019. Diurnal trends across both observation platforms showed the expected diurnal parabolic structure in NDVI with critical differences in NDVI magnitude between PhenoCams and GOES observations. One tailed T-test results show that there is variability between methods when measuring NDVI, with P-values less than 0.05 in all cases. This was anticipated due to correction factors needed for PhenoCam NDVI observations. However, additional variability can be attributed to other areas such as cloud cover, plant type, and heterogeneity. My proof-of-concept study demonstrates that raw NDVI data from both methods are often comparable, which lends credit to the notion that NDVI can be accurately observed from space at high (up to five minute) temporal resolution. With current research underway on the topics of atmospheric corrections and further surface validation, GOES has the potential to observe land surface attributes at up to 5-minute intervals across entire hemispheres for identifying phenology, disturbance and other vegetation dynamics in real time. With two hypertemporal methods at different spatial scales recently introduced, the research is primed to move towards a real time understanding of plant canopy function across the United States.Item The role of canopy tree diversity on understory plant richness and tree seedling abundance in a Pinus strobus forest in the southeastern U.S.(Montana State University - Bozeman, College of Agriculture, 2019) Davis, Stephanie Ann Morrow; Chairperson, Graduate Committee: Lisa RewThe goal of my project was to determine whether diversity in the canopy layer of a Pinus strobus dominated, mixed mesic forest in the piedmont of North Carolina showed a relationship to 1) understory richness and 2) tree seedling abundance. Forty plots were randomly selected at White Pines Nature Preserve, in Sanford, North Carolina for the study. For each plot, understory, species and tree seedling richness and density were recorded. Explanatory variables included canopy tree species richness, density and cover, total diameter at breast height (dbh) and environmental data including soil type, distance to nearest trail, and elevation. Diversity was calculated using the Simpson Index of Diversity (1-D) to show the effect of dominance in the canopy. Understory richness showed a decreasing pattern with increasing canopy diversity (p= 0.0783), suggesting a negative effect of canopy diversity on understory richness. Likewise, tree seedling abundance showed a significant negative response to canopy richness (p= 0.0146) and to all soils types (both positive and negative response). Total canopy tree basal area (diameter of tree at breast height) showed a positive relationship (p= 0.0514) to canopy species diversity (with functional similarity), which supports research showing complementarity between functionally-similar canopy tree species. Overall, results for this study suggest that, in a historically Pinus strobus-dominated forest, although greater canopy tree basal area is related to higher canopy diversity, understory richness is negatively affected by higher canopy diversity, and tree seedling abundance is negatively affected by higher canopy species richness.Item Spatial analysis of the recovery of submerged aquatic vegetation in the Hudson river estuary following the 2011-2012 hurricane seasons(Montana State University - Bozeman, College of Agriculture, 2019) Carroll, Sean Michael; Chairperson, Graduate Committee: Scott PowellSubmerged aquatic vegetation (SAV) is a critical habitat found in estuarine ecosystems throughout the world. SAV performs a multitude of ecosystem functions ranging from water quality improvement to habitat for macroinvertebrates and juvenile fish, and acts as a significant contributor to dissolved oxygen throughout the estuarine system. In the Hudson River Estuary (HRE), native SAV beds have been greatly reduced or altered by threats such as sedimentation, water quality issues, and the spread of invasive aquatic plants, as well as by disturbance from natural events such as large-scale storms. In 2011 and 2012, three hurricanes made landfall in the northeastern United States, having a tremendous impact on the Hudson River and the Hudson Valley region as a whole. SAV in the estuary was impacted by both storm surge as well as significant sediment deposition from the river's tributaries. However, in the wake of these events, there is uncertainty about the spatial patterns of SAV loss and recovery, and how these patterns are affected by the hydrology and physical characteristics of the river. Therefore, my study seeks to address this knowledge gap by investigating the impacts of these storms on SAV spatial patterns and the influence of SAV proximity to shoreline, tidal wetlands, and persistent "colony" SAV beds. I investigated these effects by analyzing overall (whole system) SAV recovery, the spatial patterns of recovery, and the correlation of recovery to prior SAV coverage and proximity to these features. Analysis was done using three years of remotely-sensed SAV GIS data, and was done at three different spatial scales. SAV coverages were determined at each scale for all three years and areal-change and percentage-change were calculated. Distance to the three aforementioned features was calculated for the fine-scale analysis. The results suggest that there was significant SAV loss river-wide between 2007 and 2014, followed by significant recovery between 2014 and 2016. Loss between 2007 and 2014 was greatest in the most upstream approximately 100 km of the river, likely a result of proximity to the Mohawk River, a major tributary and large sediment source during the storms. SAV recovery showed a similar pattern, occurring most in these upstream reaches. Distance from shoreline, tidal wetlands, and persistent SAV beds had varying impacts on SAV loss and recovery. The findings of this study help to elucidate both the potential impacts on the magnitude and patterns of vegetation loss following a large storm event and subsequent sediment flux, as well as the recovery potential of this vegetation during 'normal' years. Such information can help inform future biological studies of the HRE and watershed management decision-making.Item Water quality and physical parameters of Barnegat Bay after Hurricane Sandy(Montana State University - Bozeman, College of Agriculture, 2019) Rodenberg, Taylor; Chairperson, Graduate Committee: William KleindlBarnegat Bay is a coastal water body located off of the east coast of New Jersey. The bay is bordered by an estuary system to the west and barrier island and the Atlantic Ocean to the east. The bay is an important ecosystem for dozens of species of invertebrates, fish, mammals, birds, and amphibians, and provides millions of dollars in revenue for surrounding towns in tourism and recreation. However, coastal water bodies such as Barnegat Bay are subject to impacts from coastal storm systems such as hurricanes and tropical storms. My assessment determined how physical water properties and chemistry including water temperature, dissolved oxygen, pH, salinity, turbidity, specific conductance, and chlorophyll A were affected during landfall of Hurricane Sandy on October 29, 2012. Data on these properties was collected from available sources and were analyzed for significance in year-long data before and after hurricane landfall as well as one week before and after landfall in 2012 as compared with 2013. Results suggest that significant changes in water temperature, dissolved oxygen, pH, turbidity and chlorophyll a were observed in the week before compared with after the hurricane, while only significant changes in pH, turbidity and chlorophyll a could be observed in the year-long analysis. These data could be used to encourage further research in impacts to bay systems from coastal storms and to help create restoration plans following a storm system or preventive measures to ensure the health of the bay after major storms.