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Dating The Ste. Genevieve Limestone In West-Central Indiana Using Sr-Isotope Stratigraphy, Claire Wolfe '24 2024 DePauw University

Dating The Ste. Genevieve Limestone In West-Central Indiana Using Sr-Isotope Stratigraphy, Claire Wolfe '24

Senior Research Symposium

A section of Mississippian limestone is exposed in quarry walls at the DePauw Nature Park in Greencastle, Indiana, but its precise age is not known. This research project aimed to date the exposed wall using 87Sr/86Sr isotopic ratios to determine the absolute age. Ten samples of brachiopods and ooids were collected at various levels along the stratigraphic column. Isotope ratios were measured in these samples at ALS Scandinavia using a Neptune Plus MC-ICP-MS. Those ratios were then placed on a LOESS seawater Sr-isotope curve (McArthur, 2020) to determine the absolute age range for each sample. Whereas several samples were contaminated …


Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye 2024 University of Arkansas, Fayetteville

Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Wastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4⋅6H2O), may provide a sustainable alternative to rapidly decreasing rock phosphate reserves. Struvite can be generated via chemical and/or electrochemical precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice cultivar (Gemini 214, RiceTec) grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)] in a P-deficient silt …


A Laser Ultrasound System To Non-Invasively Measure Compression Waves In Granular Ice Mixes, J. Chris McCaslin, T. Dylan Mikesell, Hans-Peter Marshall 2024 Boise State University

A Laser Ultrasound System To Non-Invasively Measure Compression Waves In Granular Ice Mixes, J. Chris Mccaslin, T. Dylan Mikesell, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

Accurate knowledge of snow mechanical properties, including Young's modulus, shear modulus, Poisson's ratio, and density, is critical to many areas of snow science and to snow-related engineering problems. To facilitate the assessment of these properties, an innovative non-contacting laser ultrasound system (LUS) has been developed. This system acquires ultrasound waveform data at frequencies ranging from tens to hundreds of kHz in a controlled cold-lab environment. Two different LUS devices were compared in this study to determine which recorded more robust ultrasound in granular ice mix samples. We validated the ultrasound observations with poro-elastic traveltime modeling based on physical and empirical …


Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill 2024 Smith College

Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill

Geosciences: Faculty Publications

The beginning of the Phanerozoic saw two biological events that set the stage for all life that was to come: (a) the Cambrian Explosion (the appearance of most marine invertebrate phyla) and (b) the Great Ordovician Biodiversification Event (GOBE), the subsequent substantial accumulation of marine biodiversity. Here, we examine the current state of understanding of marine environments and ecosystems from the late Ediacaran through the Early Ordovician, which spans this biologically important interval. Through a compilation and review of the existing geochemical, mineralogical, sedimentological, and fossil records, we argue that this interval was one of sustained low and variable marine …


Building And Using A Hydrology Experiment For Place-Based Learning With Native American Students, Michaela Shallue 2024 Utah State University

Building And Using A Hydrology Experiment For Place-Based Learning With Native American Students, Michaela Shallue

All Graduate Theses and Dissertations, Fall 2023 to Present

Geoscience has a known diversity problem, specifically a participation gap of ethnic minority representation, and it is especially severe regarding Native American representation. To address this participation gap, an identity gap needs to be addressed first. Native students need to visualize themselves as geoscientists before they can commit to geoscience programs and careers. This project uses a hands-on, place-based learning activity as an opportunity for Native students to better see themselves as geoscientists.

A portable rainfall simulator was constructed, calibrated, and refined for use in teaching concepts about rainfall, runoff, and erosion. It was employed in place-based learning exercises with …


Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling 2024 Utah State University

Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling

All Graduate Reports and Creative Projects, Fall 2023 to Present

The rapid urbanization occurring in arid environments like the Intermountain West region of the U.S. significantly alters soil conditions. Construction of roads, buildings, and other infrastructure leads to the disturbance of soil structure, nutrient depletion, and reduced fertility. This research addresses the need for sustainable soil management practices that may restore soil health post-construction. In this study, the effectiveness of various soil amendments and application methods on specific soil parameters and turfgrass establishment in construction-disturbed soils was evaluated. The study highlights the critical role of soil amendments, particularly municipal solid waste (MSW) compost, in improving soil quality and plant growth. …


Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre 2024 Utah State University

Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre

All Graduate Reports and Creative Projects, Fall 2023 to Present

Differing crystallinities of carbonaceous material are common in fault rocks across a range of geologic settings and spatial scales and may provide constraints on strain rate, the nature of fault slip, fluid-rock interactions, and temperature variations over the earthquake cycle. The Pioneer fault at Little Fall Creek in south-central Idaho provides an excellent opportunity to study nanostructure changes of carbonaceous matter as a function of fault deformation. At this location, the Pioneer Fault exhibits a well-defined principal slip zone (PSZ) composed of multi-layered white siliceous mineralization and black carbon to graphite with a continuously exposed adjacent damage zone that includes …


Mauvais Coulee Hydrologic Simulation Data, Sharhad Wainty, Taufique H. Mahmood, Christopher Spence, Diane F. Van Hoy 2024 University of North Dakota

Mauvais Coulee Hydrologic Simulation Data, Sharhad Wainty, Taufique H. Mahmood, Christopher Spence, Diane F. Van Hoy

Datasets

The authors compiled a hydrologic model for the Mauvais Coulee Basin using Cold Region Hydrologic Platform. The datasets include observed and simulated streamflow, observed climatic data, land use maps and hydrological representative unit maps (HRU) maps. This study detected a mechanism of hydrologic change to wetting using a cold region hydrologic model during 1990-2004 period.


Arkansas Soil Erosion And Conservation Methods In Ornamental Landscapes, Abby J. Cutsinger 2024 Arkansas Tech University

Arkansas Soil Erosion And Conservation Methods In Ornamental Landscapes, Abby J. Cutsinger

ATU Research Symposium

This study will attempt to identify the best soil erosion mitigation methods for Arkansas ornamental landscape settings by comparing the strengths and weaknesses of known techniques. Since soil is not a renewable resource, we must apply conservation practices wherever possible, not just in agricultural settings. To determine the most effective erosion prevention techniques, this study will review soil studies conducted by the NRCS and NASA, as well as articles on best practices observed in ornamental landscape and agricultural industries. These are analyzed by comparing and contrasting techniques against known problems with Arkansas soil to determine which methods are most effective. …


Experimental Impact Craters Into Sloped Targets, Ashley L. Miller, Mark Cintala, Christopher Cline 2024 Winona State University

Experimental Impact Craters Into Sloped Targets, Ashley L. Miller, Mark Cintala, Christopher Cline

Research & Creative Achievement Day

Impact cratering is a process that shapes every planetary body in our solar system, including the Earth. On smaller planetary objects without atmospheres like the Moon and asteroids (e.g. Vesta and Ceres), impact cratering creates a rough surface with varying topography as opposed to a flat, horizontal surface. In general, impact cratering experiments are performed into flat targets to simplify the physics and model craters at larger planetary scales. However, the smallest craters that form on planetary surfaces are greatly affected by the local topography and cannot be understood by looking at experiments into flat targets. Dr. Anderson and her …


Evaluating Reclaimed Mines And Heavy Metal Soil Contamination, Torin A. Matthews 2024 Arkansas Tech University

Evaluating Reclaimed Mines And Heavy Metal Soil Contamination, Torin A. Matthews

ATU Research Symposium

Arkansas has a rich history of lead and zinc mining. While there are still some active mines, many historical mines have been abandoned and/or reclaimed. Although most reclamation procedures result in the burial and containment of target minerals, accessory minerals and elements can be leached out of waste materials/tailings piles and include heavy metals (i.e., Pb, As, Cd). We aim to evaluate the soil and watershed of a few abandoned/reclaimed mines in Pope County, AR, for the presence of heavy metals/source minerals. Soil and stream sediment geochemistry will be conducted using a portable x-ray fluorescence analyzer. Field work and sampling …


Summer 2024 Research Proposal: Swanberg Sanctuary Prairie Plant Community Characterization And Management Testing, Jillian Becksfort 2024 Olivet Nazarene University

Summer 2024 Research Proposal: Swanberg Sanctuary Prairie Plant Community Characterization And Management Testing, Jillian Becksfort

Scholar Week 2016 - present

Prairie management is an involved process that is focused on maintaining existing grassland plant and animal communities. Invasive species and the spread of woody shrubs and trees presents a real threat to the existing prairie. Woody stems can affect resources such as water access and nutrient availability, which may cause changes to the prairie’s unique plant communities. Management techniques like burning and mowing are commonly used to prevent woody stems from causing changes to the prairie ecosystem. The Sanctuary was restored to natural prairie habitat in 2008 and a list of planted species is available. However, no plant surveys have …


Influence Of Low-Level Condensed Tannins Concentrations In Temperate Forages On Sheep Performace, F Montossi, F Liu, J Hodgson, S T. Morris, T N. Barry, D F. Risso 2024 INIA, Uruguay

Influence Of Low-Level Condensed Tannins Concentrations In Temperate Forages On Sheep Performace, F Montossi, F Liu, J Hodgson, S T. Morris, T N. Barry, D F. Risso

IGC Proceedings (1997-2023)

Results from a series of six comparative lamb grazing trials with temperate forages are summarised, and compared with results from the literature. Condensed tannin (CT) concentrations in the diet ranged from 0.12% to 0.47% on a dry matter (DM) basis. Values were generally similar for Yorkshire fog (Holcus lanatus), perennial ryegrass (Lolium perenne) and annual ryegrass (L. multiflorum), each grown with white clover (Trifolium repens), in similar circumstances. Concentrations for tall fescue (Festuca arundinacea)/white clover pastures were relatively low, but may have been artefacts. Drenching with polyethylene glycol (PEG) to bind …


Tannin Contents Of Some Indigenous Browse Plants Of Botswana, A A. Aganga, C M. Tsopito, K M. Morake 2024 Botswana College of Agriculture

Tannin Contents Of Some Indigenous Browse Plants Of Botswana, A A. Aganga, C M. Tsopito, K M. Morake

IGC Proceedings (1997-2023)

A study was carried out to evaluate the tannin content and crude protein degradation of leaves and twigs from indigenous browsable trees which provide feed for grazing livestock on natural rangelands of Botswana. These browses include the families Leguminosae (Acacias), Capparidaceae (Boscias), Combretaceae (Combretum) and Tiliaceae (Grewias). These were found to be of good nutritive value, with the leaves having a high content of crude protein (9 - 16%) and a wide range of dry matter digestibility (37 - 69.82%). The correlation between crude protein disappearance and tannin content was found to be negative (-0.582) and significant (P<0.05).


Effect Of Tannin In Animal Diet On Nitrification Rate Of Pasture Soil Under Dung Patches, J R. Crush 2024 Ruakura Research Centre

Effect Of Tannin In Animal Diet On Nitrification Rate Of Pasture Soil Under Dung Patches, J R. Crush

IGC Proceedings (1997-2023)

The rate of formation of nitrate and ammonium in the soil under dung patches was compared for dung from animals fed either ryegrass (Lolium perenne)/white clover (Trifolium repens) or ryegrass/Lotus pedunculatus forage. Tannin derived from the Lotus did not inhibit ammonification in the soil under dung but nitrate formation was strongly inhibited. The results support the theory that polyphenolics may bind to nitrite in acid soils and cause immobilisation of mineral nitrogen. Apart from their effect of reducing the proportion of dietary nitrogen excreted in urine, tannins in animal diets may make a further contribution to …


Condensed Tannins In Tropical Legumes: Concentration, Astringency And Effects On The Nutrition Of Ruminants, R Barahona, C E. Lascano, R C. Cochran, J L. Morrill, E C. Titgemeyer 2024 Kansas State University

Condensed Tannins In Tropical Legumes: Concentration, Astringency And Effects On The Nutrition Of Ruminants, R Barahona, C E. Lascano, R C. Cochran, J L. Morrill, E C. Titgemeyer

IGC Proceedings (1997-2023)

A feeding trial was carried out to determine the effect of extractable condensed tannins (ECT) concentration and tannin astringency in tropical legumes on nitrogen (N) digestion by sheep. Test legumes were Desmodium ovalifolium (Do) and Flemingia macrophylla (Fm) which had similar concentrations of Extractable CT (9% DM) but tannins with different degree of astringency (Do, 0.6 and Fm, 0.3 g protein bound/g of ECT). Chopped sun-dried forage of each legume was sprayed with either water (control) or polyethylene glycol (PEG, 3.5% DM) to reduce ECT and fed to 8 sheep with ruminal and duodenal canulas arranged in a replicated 4 …


Effect Of Condensed Tannin In Lotus Corniculatus And Lotus Pedunculatus On Digestion Of Rubisco In The Rumen, W C. McNabb, R J. Aerts, A Brand, J S. Peters, Y L. Foo, G C. Waghorn 2024 Grassland Research Centre, NZ

Effect Of Condensed Tannin In Lotus Corniculatus And Lotus Pedunculatus On Digestion Of Rubisco In The Rumen, W C. Mcnabb, R J. Aerts, A Brand, J S. Peters, Y L. Foo, G C. Waghorn

IGC Proceedings (1997-2023)

The in vitro precipitation of ribulose-1,5-bisphosphate carboxylase (Rubisco) by condensed tannin (CT) extracted from Lotus corniculatus and Lotus pedunculatus and the effect of these CT on the in vitro rumen degradation of Rubisco was used to compare the reactivity of these CT. The chemical structure of CT from Lotus corniculatus was homogenous with epicatechin stereochemistry and mostly procyanidin units. The CT from Lotus pedunculatus was heterogenous with mostly prodelphinidin units. The amount of CT required to precipitate all the Rubisco when total soluble leaf protein was incubated with CT from Lotus corniculatus and Lotus pedunculatus was similar. Although CT from …


Nitrogen And Fiber Digestion In Sheep Fed Fresh-Frozen And Field-Dried High And Low Tannin Sericea Lespedeza, T H. Terrill, W R. Windham, C S. Hoveland, H E. Amos, B Kouakou, S Gelaye 2024 Fort Valley State University

Nitrogen And Fiber Digestion In Sheep Fed Fresh-Frozen And Field-Dried High And Low Tannin Sericea Lespedeza, T H. Terrill, W R. Windham, C S. Hoveland, H E. Amos, B Kouakou, S Gelaye

IGC Proceedings (1997-2023)

Field-drying reduces extractable condensed tannin (CT) of sericea lespedeza [Lespedeza cuneata (Dum-Cours) G. Don], but effects on specific bound and unbound forms of CT and the relationship to protein and fiber digestion in ruminants are unclear. Intake and digestibility of fresh-frozen and field-dried high- and low-tannin sericea were investigated in a feeding trial with sheep (Ovis spp.). Field-drying had no effect on crude protein (CP) and fiber content of sericea, but shifted CT from extractable to bound forms. Digestion coefficients for CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) were lower for high-tannin sericea than the low-tannin …


Alteration Of Condensed Tannin Sythesis In Transgenic Forage Legumes, F Paolocci, G Tanner, S Arcioni, F Damiani 2024 Istituto Miglioramento Genetico Piante Foraggere CNR

Alteration Of Condensed Tannin Sythesis In Transgenic Forage Legumes, F Paolocci, G Tanner, S Arcioni, F Damiani

IGC Proceedings (1997-2023)

The transformation of Lotus corniculatus plants with the maize gene Sn, reorganizes the tissue specificity of condensed tannins accumulation. In particular the transformed plants show an increase of tannin content in roots and a decrease in leaves. Molecular and enzymatic analyses suggest that the transgene can functionally substitute an endogenous unknown gene not expressed in roots and induces its silencing when it is expressed. These findings could have applications for reducing tannin content in unpalatable plants and for cloning genes involved in tannin synthesis.


Comparison Of The In Vitro Fermentation Characteristic Of Fractionated Alfalfa And Sainfoin, L R. McMahon, M Goto, T A. McAllister, G A. Jones, K J. Cheng 2024 Agriculture and Agri-Food Canada Research Centre

Comparison Of The In Vitro Fermentation Characteristic Of Fractionated Alfalfa And Sainfoin, L R. Mcmahon, M Goto, T A. Mcallister, G A. Jones, K J. Cheng

IGC Proceedings (1997-2023)

Alfalfa and sainfoin leaves were lyophilized and ground (A, S, respectively) or were fractionated into soluble (ASOL, SSOL) and insoluble (AINS, SINS)components and lyophilized and incubated in vitro with diluted ruminal fluid for 24h. Whole leaf and soluble fractions were also incubated with polyethylene glycol 8000 (PEG). Gas production (GP), ammonia concentration [NH3] and volatile fatty acid (VFA) production were lower (P< 0.05) from S and SSOL than from A and ASOL Insoluble fractions differed only in [NH3] (SINS < AINS, P < 0.05). Inclusion of PEG increased (P < 0.05) GP, [NH3] and VFA production from whole leaf and soluble fractions of sainfoin, but not alfalfa. Inactivating the condensed tannins in sainfoin with PEG overcame differences in degradability between these two forages.


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