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University of Arkansas, Fayetteville

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Full-Text Articles in Earth Sciences

Soil Moisture Regime Effects On Greenhouse Gas Emissions In A Native Tallgrass Prairie In The Ozark Highlands, Thomas William Dockery Jul 2026

Soil Moisture Regime Effects On Greenhouse Gas Emissions In A Native Tallgrass Prairie In The Ozark Highlands, Thomas William Dockery

Graduate Theses and Dissertations

The Ozark Highlands is an ecoregion in the mid-southern portion of the United States that is characterized by a mosaic of tallgrass prairies, oak (Quercus spp.) savannas, and oak-hickory (Carya spp.) forests, which represents a unique biophysical transition zone between the relatively dry grasslands of the west and the humid forests of the southeast. Quantifying greenhouse gas (GHG) emissions, namely carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), from natural, undisturbed ecosystems is critical to understanding atmospheric warming and climate-change implications. The objective of this study was to simultaneously evaluate CO2, CH4, and N2O emissions in an aquic and …

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Potassium Fertilization Timing And Critical Stalk Potassium Concentration As Tools To Improve Corn Production, Gabriela Andrade Leite Mengez Jul 2026

Potassium Fertilization Timing And Critical Stalk Potassium Concentration As Tools To Improve Corn Production, Gabriela Andrade Leite Mengez

Graduate Theses and Dissertations

Potassium (K) is a common yield-limiting nutrient in Mid-Southern U.S. corn (Zea mays L.) production, emphasizing the importance of effective diagnostic tools to support fertilizer decision-making. This study integrated two approaches to improve K management in irrigated corn systems: (i) evaluating K fertilization timing to identify in-season opportunities for correcting K deficiency, and (ii) developing a corn stalk-based diagnostic test to assess end-of-season K and nitrate-nitrogen (NO₃-N) status and fertilizer adequacy. Seven (2024-2025) and eight (2023-2024) field trials were conducted across Arkansas for the K application timing and stalk testing studies, respectively. For the K timing study, fertilizer-K (112 kg …

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Chaotropic And Kosmotropic Effects Of Brines On Protein Structure: Habitability Across The Solar System, Shelby Dawn Osborne Jul 2026

Chaotropic And Kosmotropic Effects Of Brines On Protein Structure: Habitability Across The Solar System, Shelby Dawn Osborne

Graduate Theses and Dissertations

Salts exhibit unique and specific effects on biomolecular structure depending on the physical nature of the salt (ion density, formation of hydration shells, direct binding to protein). This thesis implements biochemical, thermodynamic, and computational methods to investigate how the nature of the salt effects protein structure, which aids in defining the habitability of various brine solutions. By using simple proteins and solar system relevant salts, we inspect the physical reactions of proteins to these saltwater environments to understand which salts stabilize or destabilize protein structure. Several methods of experimentation are utilized to provide an understanding of the interaction relevant to …

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Investigation Of Early To Late Cretaceous North American Ecosystems And Paleoclimate Using Geochemical Proxies, Clayton William Forster Jul 2026

Investigation Of Early To Late Cretaceous North American Ecosystems And Paleoclimate Using Geochemical Proxies, Clayton William Forster

Graduate Theses and Dissertations

The relationships between the environment and an organism can be traced through stable isotope and trace element geochemistry. This thesis explores the stable oxygen and carbon isotopic composition of fossil vertebrate assemblages in pursuit of revealing the relationships between dinosaurs and their archosaur relatives with the environment in which they lived during the Cretaceous. The Cretaceous Period of North America experienced some of the hottest intervals in the Phanerozoic Eon and the continental vertebrate taxa that existed during this time recorded these periods within the stable isotopic composition of their skeletal bioapatite. Oxygen isotopes in the bioapatite of vertebrates reflect …

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Instructions To Authors, Academy Editors Jun 2026

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Journal Acknowledgements And Editorial Board, Academy Editors Jun 2026

Journal Acknowledgements And Editorial Board, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Keynote Address And Meeting Program, Academy Editors Jun 2026

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors Jun 2026

Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Sperm Morphology In The Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth Jun 2026

Sperm Morphology In The Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth

Journal of the Arkansas Academy of Science

Studies by Scheltinga et al. (2002) and Scheltinga and Jamieson (2003) provide the most comprehensive analysis and only review of sperm morphology in Narrow-Mouthed Frogs (family Microhylidae). Of the 490+ species known to occur in this anuran family (Vitt and Caldwell 2014), only 3 are distributed in the United States (Powell et al. 2016), and 2 of these occur in Arkansas (Trauth et al. 2004). Surprisingly, sperm studies on only 12 microhylid species have been conducted (Scheltinga and Jamieson 2003), and no sperm studies are available on any North American species.

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Multiple Nuclear Configurations And Microtubular Arrangements In Spermatozoa Of The Western Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth Jun 2026

Multiple Nuclear Configurations And Microtubular Arrangements In Spermatozoa Of The Western Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I examined the ultrastructure of spermatozoa of the Western Siren, Siren nettingi, using transmission electron microscopy. My primary objective in this study was to elucidate, for the first time, the unique morphological complexity of biflagellated sperm in this species. This study also represents my fifth addition in a series of investigations that highlight the novel nature of all aspects of spermatogenesis in this salamander I show the basic sperm transverse and sagittal design which includes a nucleus, 2 axial fibers supporting 2 undulating membranes which have 2 axonemes residing at their terminal ends, several circular mitochondria, and several electron-dense masses. …

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Binucleation And Seasonal Cycle Of Sertoli Cells In The Western Lesser Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth Jun 2026

Binucleation And Seasonal Cycle Of Sertoli Cells In The Western Lesser Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I examined binucleation and the seasonal cycle of Sertoli cells in the Western Siren (Siren nettingi) using light microscopy and transmission electron microscopy. My primary objective in this study was to report, for the first time, the presence of double nuclei in Sertoli cells in a salamander. This study also represents the sixth contribution in a series of investigations that highlight the novel nature of all aspects of spermatogenesis in this unique salamander. My findings add to a growing list of extraordinary morphological and reproductive features that distinguish this salamander from all other vertebrates.

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Distal Urogenital Anatomy And Epithelial Morphology In The Male Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth Jun 2026

Distal Urogenital Anatomy And Epithelial Morphology In The Male Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I investigated the microanatomy of the distal urogenital system in male Eastern Narrow-Mouthed Frogs (Gastrophryne carolinensis) from a small sample (n = 5) collected in central Arkansas in April, May, and July (2021) and May 2022. Specifically, my primary goals were to elucidate the histology of the following: (1) the paired Wolffian (urogenital) ducts caudally from the kidneys to their merging with the urodeum of the cloaca, (2) the structure of seminal vesicles, and (3) the epithelial morphologies among the distal urogenital tract, the posterior alimentary canal, and the cloaca. My histological analysis confirmed the presence of …

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Academy Presidents And Institutional Members, Academy Editors Jun 2026

Academy Presidents And Institutional Members, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Table Of Contents, Academy Editors Jun 2026

Table Of Contents, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Journal Of The Arkansas Academy Of Science Volume 79, Academy Editors Jun 2026

Journal Of The Arkansas Academy Of Science Volume 79, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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The Soil Crisis In Modern Food Systems: Rethinking Agricultural Land Use, Antonia Moure Richard Jun 2026

The Soil Crisis In Modern Food Systems: Rethinking Agricultural Land Use, Antonia Moure Richard

Journal of Food Law & Policy

Feeding a larger world while preserving the resource that makes agriculture possible—soil—poses a governance problem. By 2050, food systems must support 9.8 billion people even as prevailing practices continue to degrade soils that are non-renewable on human timescales. Technological fixes (e.g., vertical farming, hydroponics) may complement production, but they cannot substitute for soil at scale. The question that follows is simple: are current uses of soil compatible with the future needs of food systems? This article argues that without a shift in governance, short-run productivity gains are achieved by drawing down the soil asset, thereby undermining long-run food security and …

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Real-Wastewater-Derived-Struvite Effects On Micronutrients In Runoff Water, Lauren E. Pruitt May 2026

Real-Wastewater-Derived-Struvite Effects On Micronutrients In Runoff Water, Lauren E. Pruitt

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Phosphorus (P) is an essential nutrient needed in agriculture for proper plant growth and development and is often introduced into agricultural systems in the form of synthetic P fertilizers. Mined rock phosphate is the primary P source for the production of synthetic P fertilizers and is a finite resource. Struvite (MgNH4PO4·6H2O) is a compound that can be precipitated from municipal wastewater, recovering P, and is currently being evaluated for its potential use as an alternative fertilizer-P source. The objective of this study was to evaluate the effects of fertilizer-P source [i.e., synthetic electrochemically precipitated …

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Soil Moisture Regime Effects On Near-Surface Soil Chemical Properties In Alfisols Under Native Tallgrass Prairie In Arkansas, Sydney M. Talley May 2026

Soil Moisture Regime Effects On Near-Surface Soil Chemical Properties In Alfisols Under Native Tallgrass Prairie In Arkansas, Sydney M. Talley

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Tallgrass prairie ecosystems provide many crucial ecosystem services, including nutrient cycling and storage, organism habitat, and soil and water conservation. However, tallgrass prairies are considered an endangered ecosystem, particularly in the Ozark Highlands and Grand Prairie regions of Arkansas, where less than 0.05% of Arkansas’ original prairie land area remains. Understanding soil nutrient supplies over time in native tallgrass prairie ecosystems is critical for quantifying the success of restoration and rehabilitation activities. The objective of this study was to evaluate the effects of soil moisture regime (SMR) (i.e., aquic and udic), region (i.e., Ozark Highlands and Grand Prairie), and their …

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Grazed Pasture Effects On Greenhouse Gas Emissions In The Ozark Highlands, Tyler Buchanan May 2026

Grazed Pasture Effects On Greenhouse Gas Emissions In The Ozark Highlands, Tyler Buchanan

Graduate Theses and Dissertations

In the United States (US), grazinglands serve as the main foundation for the livestock industry, and, in Arkansas specifically, pastures are essential for rotational grazing and dairy operations. Climate change is increasingly becoming a concern in the agriculture industry, largely caused by anthropogenic activities increasing greenhouse gas (GHG) concentrations in the atmosphere, at least partly due to the nutrient recycling that occurs from animal manure additions in grazinglands. Therefore, quantifying GHG emissions from pastures is essential to better understanding the impacts of grazing on the environment. The objective of this study was to quantify and evaluate the potential effects of …

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Sedimentary Provenance Of The Pliocene – Pleistocene Giant Foresets Formation, Offshore Taranaki Basin, Aotearoa New Zealand, Anurag Kulkarrni May 2026

Sedimentary Provenance Of The Pliocene – Pleistocene Giant Foresets Formation, Offshore Taranaki Basin, Aotearoa New Zealand, Anurag Kulkarrni

Graduate Theses and Dissertations

Sediment input and dispersal in the Taranaki Basin, offshore New Zealand’s North Island, was influenced by a complex interplay of ocean currents and sea level fluctuations over the late Neogene. This period of time was recorded in the Pliocene-Pleistocene Giant Foresets Formation (GFF) that represents a rapid progradation of the western continental shelf into the basin. High sedimentation rates during this time were likely a major contributing factor to the emplacement of multiple, large-scale (up to ~3,500 km3) mass-transport deposits (MTD) that were caused by shelf and slope collapse within the GFF of similar scale to that of the well-studied …

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From Phenology To Yield Zones: Functional Clustering Of Satellite Time Series For Crop Growth Monitoring, Ikram Morso May 2026

From Phenology To Yield Zones: Functional Clustering Of Satellite Time Series For Crop Growth Monitoring, Ikram Morso

Graduate Theses and Dissertations

Remote sensing and land surface phenology provide a strong basis for characterizing crop development, but their usefulness for within-field yield-zone delineation depends on whether crop development is analyzed as a phenological trajectory and whether the resulting zones are evaluated with spatially defensible statistics. These questions are especially relevant in soybean production because soybean is one of the most important row crops in the United States and the country’s dominant oilseed crop. This relevance is strong in Arkansas, where soybean is a major component of agricultural production. In soybean production, within-field yield variability reflects the combined influence of soil properties, stand …

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A Spatial Analysis Of Socioeconomic Characteristics And Community Vulnerability To Natural Hazards In Arkansas, Emma Steuber, Brad Peter May 2026

A Spatial Analysis Of Socioeconomic Characteristics And Community Vulnerability To Natural Hazards In Arkansas, Emma Steuber, Brad Peter

Geosciences Undergraduate Honors Theses

Natural hazards have become more frequent in recent years, and because of their destructive impacts, it is crucial to locate regions that are most affected historically by hazardous events and identify what socioeconomic characteristics co-occur spatially. While many studies have analyzed this relationship at national and state scales, few have focused specifically on Arkansas, and even fewer have incorporated multiple socioeconomic characteristics. Comparing the spatial distribution of community characteristics in Arkansas with zones of common natural hazards is essential for identifying who is most at risk. This study utilizes Geographic Information Science (GISci) to examine and map the spatial relationship …

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Phase Equilibria Modeling Constraints On Seismic Velocity And Density For Mafic Granulites In The Athabasca Granulite Terrane, Western Canadian Shield, Olivia Wyllie May 2026

Phase Equilibria Modeling Constraints On Seismic Velocity And Density For Mafic Granulites In The Athabasca Granulite Terrane, Western Canadian Shield, Olivia Wyllie

Geosciences Undergraduate Honors Theses

Samples of mafic granulite and eclogite from the Athabasca granulite terrane, thought to be representative of the lower continental crust, were analyzed via bulk geochemistry analysis and seismically modelled with Perple_X v.7.1.6. Modeled P-wave speeds, S-wave speeds, and densities for the samples were graphed by region and calculated for wet (1.00 wt.% H2O) versus dry (0.01 wt.% H2O) conditions at 460 °C and 648 °C. The samples were found to have higher median P-wave values than those determined by Rudnick and Fountain (1995; 7.4 km/s to 7.8 km/s, as compared to 6.9 km/s to 7.2 km/s). This indicates both a …

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Age And Characteristics Of Quaternary Fluvial And Dune Deposits Along The Arkansas And Cimarron Rivers In Osage And Pawnee Counties, Oklahoma, Barry A. Duncan May 2026

Age And Characteristics Of Quaternary Fluvial And Dune Deposits Along The Arkansas And Cimarron Rivers In Osage And Pawnee Counties, Oklahoma, Barry A. Duncan

Graduate Theses and Dissertations

Quaternary aeolian and fluvial deposits along the Arkansas and Cimarron Rivers in Osage and Pawnee counties of central Oklahoma, record Late Pleistocene and Holocene fluvial landscape history in the eastern Osage Plains. Sediment supply, climate variability, channel incision, and channel migration control this landscape evolution. Sediment supply of both streams is dominantly sand. Late Pleistocene and Holocene precipitation have varied with periods of drought alternating with increased precipitation and warming. The study area is near the eastern boundary of substantial aeolian activity with drought and aeolian reworking of fluvial sand more severe to the west. This study examines the sediment, …

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Geothermal Gradient And Lithium Co-Generation Power Potential In Lafayette County, Arkansas, Juan Agustin Falquez May 2026

Geothermal Gradient And Lithium Co-Generation Power Potential In Lafayette County, Arkansas, Juan Agustin Falquez

Graduate Theses and Dissertations

The Smackover formation in south Arkansas is a known reservoir for brines with high temperature and salinity. Recently, Smackover formation brines in Lafayette County, Arkansas are a target for lithium extraction. A county-wide dataset of Bottomhole Temperatures (BHT) is used to estimate a lower bound geothermal gradient of 36 C/km and a reservoir temperature of 116 C at an approximate depth of 2725 m. The high temperatures make the brines a candidate for geothermal power co-generation. Geothermal power co-generation can be achieved by implementing an Organic Rankine Cycle (ORC) power plant. The Southwest Arkansas Lithium project anticipates a total of …

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Of Dunes And Ice: A Surface-Atmosphere Investigation Of Mars Co2 Sublimation Features And Titan Aeolian Fields, Racine D. Cleveland May 2026

Of Dunes And Ice: A Surface-Atmosphere Investigation Of Mars Co2 Sublimation Features And Titan Aeolian Fields, Racine D. Cleveland

Graduate Theses and Dissertations

This dissertation investigates a central question: How do planetary boundary layer processes manifest in observable surface geomorphology, and how can planetary imagery be used to quantify those effects? The planetary boundary layer (PBL) governs near-surface exchanges of momentum, heat, and volatiles, yet direct atmospheric measurements remain spatially and temporally limited on most planetary bodies. By analyzing geomorphic features preserved in high-resolution imagery, this work quantifies how boundary-layer processes leave measurable signatures on planetary surfaces. For Mars, high-resolution images from the Mars Reconnaissance Orbiter (MRO) HiRISE instrument were used to map CO2 sublimation features, or Swiss Cheese Features (SCFs), on the …

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Geospatial Analysis Of The Influence Of Wastewater Disposal On The Induced Seismicity In Oklahoma, Usa, Kristine Nagy May 2026

Geospatial Analysis Of The Influence Of Wastewater Disposal On The Induced Seismicity In Oklahoma, Usa, Kristine Nagy

Graduate Theses and Dissertations

Seismic records over the past decade and a half have indicated a significant increase of earthquakes in the state of Oklahoma and the evidence has strongly suggested the rise is likely caused by substantial wastewater disposal operations, a subsequent process of oil and natural gas extraction. This study investigated the relationship between wastewater disposal via injection wells, and its influence on inducing earthquakes in Oklahoma by employing Geographic Information System (GIS) tools for geospatial data integration and spatial analysis using United States Geological Survey (USGS) earthquake data and Underground Injection Control (UIC) Class II well data sourced from the Oklahoma …

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Quantifying The Short-Term Hydrogeologic Responses Of Highway Construction In Hot Springs, Arkansas, Billy Jack Summerford May 2026

Quantifying The Short-Term Hydrogeologic Responses Of Highway Construction In Hot Springs, Arkansas, Billy Jack Summerford

Graduate Theses and Dissertations

In late 2020, excavation for the Highway 5 Bypass in Hot Springs, Arkansas exposed seepage faces along roadcut walls. Groundwater levels at nearby wells decreased by up to 20.9 ft and have remained ~20 ft below pre-construction values on average. This study quantifies changes in storage in the unconfined aquifer within the Hot Springs thermal recharge zone associated with the seepage faces using a numerical groundwater model calibrated to pre-construction head at well ARb4. Model scenarios are used to evaluate whether construction-induced seepage or drought best explains the decrease from late 2020 to early 2021. The numerical groundwater simulation represented …

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Impacts Of Climate-Smart Agriculture On Greenhouse Gas Emissions In Southeast Arkansas Cotton, Cassandra Seuferling May 2026

Impacts Of Climate-Smart Agriculture On Greenhouse Gas Emissions In Southeast Arkansas Cotton, Cassandra Seuferling

Graduate Theses and Dissertations

Increasing concerns of climate change have led to the evaluation of greenhouse gas (GHG) emissions [i.e., carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O)] from agroecosystems, particularly cotton (Gossypium hirsutum) production. Technology improvement and conservation agriculture methods [i.e., reduced-tillage (RT) instead of conventional tillage (CT) and the use of cover crops (CC)] require further evaluation regarding GHG emissions from Arkansas cotton production. The first objective of the study was to evaluate four gas-flux-determination methods [i.e., linear or exponential regression models, with negative fluxes (WNF) included in the dataset or replacing negative fluxes (RNF)] on CO2, CH4, and N2O fluxes …

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Groundwater Responses To Tidal Restoration At Pelican Marsh And Sea-Level Rise In Elkhorn Slough, California, Julie E. Nelson May 2026

Groundwater Responses To Tidal Restoration At Pelican Marsh And Sea-Level Rise In Elkhorn Slough, California, Julie E. Nelson

Graduate Theses and Dissertations

Coastal wetlands represent a dynamic but vulnerable terrestrial-aquatic interface with future resilience controlled by historic hydrologic alterations, sea-level rise, and groundwater extraction. In diked coastal settings, poor tidal connectivity can degrade habitat from the impoundment of freshwater or hypersaline surface waters. Restoring tidal connectivity could foster marsh revitalization, but altering the surface hydrologic system could lead to unwanted salinity intrusion in shallow aquifers. Saline groundwater intrusion degrades freshwater quality and, while inevitable with sea-level rise, could be accelerated with tidal marsh restoration. To investigate this, I developed a steady-state groundwater flow model of Pelican Marsh, a diked, muted tidal marsh …

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