Earth Sciences Commons^™

Review Of 50 Years Grassland Farming And Trends Of Development In The Further Intensification Of Forage Production In The German Democratic Republic, Eberhard Wojahn

IGC Proceedings (1977-2023)

This our XIII International Grassland Congress is being held at the invitation of the Govern­ment of the German Democratic Republic following the decision of the XII International Grassland Congress in Moscow in 1974 that this Congress shall be held as a jubilee event here in Leipzig. It is the Jubilee Congress reminding us of the First International Grass­land Congress which was held 50 years ago, during the last days of May, 1927, in this time-honoured University town and centre of world trade. Because of that jubilee character this XIII International Grassland Congress is of very special importance.

Influence Of Feeding On Health And Productivity Of Ruminants, Alexander Sommer

IGC Proceedings (1977-2023)

As to the utilization of plant matter not suited for direct consumption by man, ruminants are of outstanding importance. This fact is related with the function of their specific stom­ach system. The paper discusses the microbial protein synthesis from NPN compounds. When 50 per cent of digestible crude protein required by fattening cattle were replaced, daily live weight gains of 997 g were reached; beef quality was not affected. Similarly favourable results were obtained with dairy cows when replacing by NPN compounds 50 to 100 per cent of extracted meals. Further on, the problem of crude-fibre diges­tion in connection with …

Crustal Structure Of The Vøring Plateau And Vøring Spur From Joint Refraction And Reflection Travel-Time Tomography, Anika Nawar Mayeesha

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Crustal architecture of the Vøring Plateau and Vøring Spur in the mid-Norwegian continental margin remains debated because the geophysical data in the area do not uniquely constrain whether the crust is continental, oceanic, or transitional. This study reanalyzes wide-angle ocean-bottom seismometer data from Profile 11-03 across the Vøring passive continental margin using joint travel-time tomography of crustal refractions and Moho reflections. A total of 6,760 first-arrival picks and 542 PmP picks from sixteen instruments were inverted for P-wave velocity and reflector depth. Three starting models were inverted independently to test sensitivity to the initial crustal configuration. The first two used …

Observing System Simulation Experiments To Investigate Impacts Of Deep-Tropospheric Uas Flights On Forecasts, Kenneth Alexander Swan

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Uncrewed aircraft systems have emerged as a promising option to address meteorological gaps in observations in the lower troposphere. With recent advancements, UAS may be able to address gaps aloft in areas that lack coverage from radiosondes and commercial aircraft. UAS have shown the potential to significantly benefit NWP forecasts from profiles in the lowest 2 km AGL, but the impact of UAS profiles to the tropopause has yet to be quantified. Additionally, the impacts of hazardous flying conditions that UAS would encounter need to be addressed to guide future UAS capabilities. To address these questions, we designed an observing …

Block Kinematics, Interseismic Coupling And Fault Slip Rates In The Aegean Region From Gps And Earthquake Slip Vector Data: 1. Upper Plate Structures, Konstantinos Chousianitis, Sotiris Sboras, Volkan Özbey, Robert Mccaffrey, Semih Ergintav

Geology Faculty Publications and Presentations

We represent the active deformation of the Aegean region with an elastic‐kinematic block model composed of a finite number of rotating crustal blocks whose boundaries coincide with major active structures. A total of 832 GPS velocities and 146 earthquake slip vectors were inverted to provide estimates of block rotations and interseismic locking on block‐bounding faults so as to best reproduce the observed deformation field. Our regional model allowed us to derive a self‐consistent set of geodetic slip rates for upper plate faults and the Hellenic subduction system, the results of which are presented in a companion paper, and to determine …

Elemental Analysis Of Upper Devonian To Lower Mississippian Organic-Rich Mudstone Cores From Kentucky By Portable X-Ray Fluorescence (Pxrf), Alex M. Washburn

KGS Research Data Set

This dataset contains high-density portable X-ray fluorescence (pXRF) elemental analyses of 1,867 m (6,125 ft) of Upper Devonian to Lower Mississippian organic-rich mudstone cores from Kentucky. Analyses were collected from cores across the Illinois Basin, Cincinnati Arch, and Appalachian Basin to support regional evaluation of elemental variability, chemostratigraphy, and redox-sensitive trace-metal enrichment in Devonian–Mississippian mudstone successions. All measurements were conducted using a Bruker Tracer 5 pXRF analyzer with the factory “Mudrock Air” calibration, using analytical settings optimized for both low-atomic-number elements and transition metals/redox-sensitive trace elements. Reference materials SARM-41 and SGR-1 were analyzed throughout the analytical sequence to monitor instrument …

Synoptic Conditions Favoring Tropical Cyclone-Enhanced Southwest Monsoon High Precipitation Events In The Philippines, Alwin Andriel L. Bathan, Lyndon Mark P. Olaguera, Faye Abigail T. Cruz, Jose Ramon T. Villarin, John A. Manalo, Jun Matsumoto

SOSE Affiliate: Manila Observatory

The interaction of tropical cyclones (TCs) with the southwest monsoon frequently causes heavy precipitation events (HPEs) and widespread flooding across the Philippines. Despite their substantial socio-economic impacts, the synoptic conditions that favor these events remain insufficiently understood, underscoring the need for systematic investigation to help improve forecasting and risk assessment. Lag composite analysis of daily rainfall records and reanalysis data from July to September for the period 1981–2023 shows that HPEs are more likely to occur when: (1) enhanced monsoon westerlies are present over the tropical Indian Ocean for at least nine days before the HPE, (2) a TC passes …

Book Review: Atlas Of Minerals And Igneous And Metamorphic Rocks In Thin-Section (2025) By Alessandro Da Mommio And Victoria Pease., Kenneth L. Brown

Geology and Environmental Geoscience Faculty Publications

"Optical mineralogy and petrography not only equip us with the skills necessary to address society’s growing need for rock and mineral resources but also awaken a deeper curiosity—inviting us into moments of discovery that change the way we understand these resources. From observing the vibrant and mesmerizing interference colors of a dunite thin section to examining the uniaxial interference figure of calcite, many of us can still recall the first time we peered through the oculars of a polarizing microscope. Atlas of Minerals and Igneous and Metamorphic Rocks in Thin-Section is an exceptional reference textbook, which nurtures that curiosity and …

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 …

Glacier Elevation Difference Data For The Conterminous U.S., Andrew G. Fountain, Bryce Allen Glenn, Christopher Mcneil, Brian Menounos

Geology Faculty Datasets

Historic and recent elevation data for the glaciers in the conterminous US were differenced to estimate glacier mass and volume change.

Historic glacier elevations were obtained from the USGS National Elevation Dataset (https://doi.org/10.15760/geology-data.04), a digitized product from the USGS 1:24,000 paper topographic maps that included the glacier extent (Gesch, 2007). Recent glacier elevations were derived from aerial lidar and from satellite radar. The lidar data were largely obtained from the USGS 3D Elevation Program (Stoker and Miller, 2022; US Geological Survey, 2024), and filtered by acquisition date using only those data collected between mid-summer and early autumn. The …

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 …

The Geologic History Of The Chehalis Forearc Basin, Washington State, Usa, R. L. Moe, J. Bershaw, L. M. Staisch, A. R. Streig

Geology Faculty Publications and Presentations

The Chehalis basin is located between the Cascade arc and the Coast Range in southwest Washington State. It consists of sedimentary and volcanic rocks deposited throughout the Cenozoic and is underlain by the Siletzia terrane, a thick, large igneous province accreted in the Eocene. Here, we constrain evolution of the Chehalis basin depocenter using isochore maps derived from isostatic gravity anomalies, borehole data, and stratigraphy for several time periods: the Eocene (47.6–36.8 Ma), the Oligocene (36.8–20 Ma), and the Neogene (20–0 Ma). Our results suggest that local subsidence is driven by deformation on faults that bound and intersect the basin. …

Farm Workers And The Structural Basis Of Climate Change Perceptions, Cody Mortell, Anna Erwin, Zhao Ma, Dongkyu Kim, Elizabeth Rodriquez, Marla Perez-Lugo

School of Earth, Environmental, & Marine Sciences Faculty Publications

Farm workers are particularly vulnerable to climate change, especially from extreme heat; however, little is known about how they perceive this risk. This study examines climate change perceptions (CCP) among 404 farm workers surveyed in person in the Lower Rio Grande Valley, Texas from April to May 2024. Guided by Pierre Bourdieu’s theory of practice, we conducted a latent class analysis of economic, cultural, social, and symbolic capital indicators to identify distinct class profiles. We then assessed CCP by latent profile, using two primary outcome variables: (1) perceived temperature trends in the region (assessed alongside NOAA data) and (2) perceived …

An Emergent Seafood Nationalism Takes Hold In The United States, Owen Temby

School of Earth, Environmental, & Marine Sciences Faculty Publications

This paper introduces the concept of ‘seafood nationalism’ to describe how, since 2024–2025, the United States increasingly uses tariffs, trade remedies, food safety enforcement and origin-based rules to favour American seafood over foreign products. Federal actions include Executive Order 14276, Restoring American Seafood Competitiveness, which directs agencies to address unfair trade practices, unsafe imports and to develop a coordinated seafood trade strategy. Additional measures include a tariff package imposing a 10% duty on nearly all seafood imports and 30% on seafood from China, as well as new anti-dumping and countervailing duty orders on warm-water shrimp. This paper presents Gulf …

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 …

Micro-Topographic Control On Soil Moisture And Ph Dynamics In A Northern Peatland Ecosystem: A Case Study From Saco Heath, Maine, Henry Mahoney

Student Publications

Peatland ecosystems are characterized by complex structural microtopography, prominently featuring elevated hummocks and depressed hollows that establish critical micro-environmental and ecohydrological gradients. This study investigates the influence of micro-topographic positioning on soil moisture and pH dynamics at the Saco Heath Preserve; a raised acid bog located in southern Maine. Data collection was focused entirely within Sphagnum moss, which serve as the dominant vegetative component across multiple structural hummocks and hollows. Using a systematic temporal framework and a robust spatial sampling strategy (n = 100 per micro-habitat) between July 16 and August 16, we quantified physical moisture contents and chemical pH …

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 …

Block Kinematics, Interseismic Coupling And Fault Slip Rates In The Aegean Region From Gps And Earthquake Slip Vector Data: 2. Hellenic Subduction System, Konstantinos Chousianitis, Volkan Özbey, Sotiris Sboras, Robert Mccaffrey, Semih Ergintav

Geology Faculty Publications and Presentations

The Hellenic subduction system is the primary locus of Nubia‐Eurasia convergence, yet thedistribution of strain accumulation along it is still debated. Here, we invert 832 geodetic velocities and 146earthquake slip vectors to assess the spatial variability of interseismic locking and provide new constraints onthe rate of slip deficit accumulation. We find that the subduction interface beneath southwestern Peloponneseand across the area from offshore south Peloponnese to offshore southwest of western Crete hosts three patchesof low to moderate locking (0%–40%) at 10–50 km depth whose slip rate deficits account for ∼15–30% of thetotal plate convergence. The offshore weakly locked patches show …

Hydrogeochemical Characterization Of Groundwater In Fractured Crystalline Basement Aquifers In Dodoma, Central Tanzania: Implications On Water Quality For Domestic And Irrigation Applications, George J. Ishabairu, Simon R. Melchioly, Charles H. Kasanzu, Gabriel D. Mulibo

Tanzania Journal of Science

Assessment of groundwater hydrogeochemistry characteristics of aquifers plays a vital role in establishing water quality status and its suitability for human and industrial use. The main objective of this research was to carry out hydrogeochemical characterization of groundwater and assess its impacts on water quality and spatial variability of groundwater geochemistry in Dodoma, Tanzania. The methods used include groundwater sampling, laboratory analysis to determine physico- chemical parameters and data processing to classify the groundwater hydrochemical facies. The results show that the average value for pH is 7.2, for electrical conductivity (EC) is 1108 µS/cm and for total dissolved solids (TDS) …

Hydroclimatic Whiplash Across The Contiguous United States: Characterizing Wet–Dry Transitions In Pdsi And Phdi, James Lam, Thomas Christopher Piechota

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Hydroclimatic whiplash, characterized by rapid transitions between wet and dry conditions, poses a growing challenge for water resource management and ecosystem stability. However, the spatial and statistical characteristics of wet–dry transitions across the contiguous United States are not fully understood. This study analyzed Palmer Drought Severity Index (PDSI) and Palmer Hydrological Drought Index (PHDI) records from 344 NOAA climate divisions spanning 1895–2024. Whiplash was defined as a transition between severe drought and severe wetness within 12-month rolling windows. Statistical descriptors including lag-1 autocorrelation, variance, and skewness were evaluated for whiplash and non-whiplash windows to assess differences between them. Whiplash hotspots …

An Overlooked Terrestrial Archive: Freshwater Cements And Hydroclimate Signals In Quaternary Glaciogenic Deposits, Owen F. Mccaffrey, Ian Z. Winkelstern, Tara A. Kneeshaw, Melinda C. Higley

University Faculty Publications and Creative Works

Quaternary glaciogenic deposits, which serve as vital groundwater aquifers, are often partially cemented with carbonate minerals, but the timing of emplacement of these cements and their geochemical conditions of formation remain understudied. Here, we integrated petrography, δ¹⁸O, Mg/Ca, and clumped isotope (Δ₄₇) data from two calcitecemented outcrops in western Michigan (USA) to investigate the origin of glacial sediment cements. The two sites have contrasting topographic and textural settings reflecting distinct formation conditions. The elevated Wabasis Lake deposit records sequential phreatic-to-vadose cementation, while the Cherry Valley Sands site, very close to the modern water table, shows a …

R Code And Supporting Data For "Fast And Slow Water Handling Strategies Explain Pinyon Pine Decline And Juniper Expansion", Andrew Kulmatiski, Muhammad Faraz Rehman

Browse all Datasets

This repository contains the datasets, R scripts, HYDRUS-1D model files, weather data, and supporting materials used for the M.S. thesis, "Fast and Slow Water Handling Strategies Explain Pinyon Pine Decline and Juniper Expansion." The study investigated root water uptake and water-use strategies of pinyon pine (Pinus edulis) and Utah juniper (Juniperus osteosperma) using stable isotope tracer experiments, soil water flow modeling, leaf water potential measurements, stomatal conductance measurements, and environmental data collected across an aridity gradient in southern Utah, USA.

An Overlooked Terrestrial Archive: Freshwater Cements And Hydroclimate Signals In Quaternary Glaciogenic Deposits, Owen F. Mccaffrey, Ian Z. Winkelstern, Tara A. Kneeshaw, Melinda C. Higley

University Faculty Publications and Creative Works

Quaternary glaciogenic deposits, which serve as vital groundwater aquifers, are often partially cemented with carbonate minerals, but the timing of emplacement of these cements and their geochemical conditions of formation remain understudied. Here, we integrated petrography, δ¹⁸O, Mg/Ca, and clumped isotope (Δ₄₇) data from two calcitecemented outcrops in western Michigan (USA) to investigate the origin of glacial sediment cements. The two sites have contrasting topographic and textural settings reflecting distinct formation conditions. The elevated Wabasis Lake deposit records sequential phreatic-to-vadose cementation, while the Cherry Valley Sands site, very close to the modern water table, shows a …

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Journal Acknowledgements And Editorial Board, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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

Journal of the Arkansas Academy of Science

No abstract provided.

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.

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. …

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.