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Synthesis Study Of Evapotranspiration Evolution In The Mekong Delta Induced By Land Use And Land Cover Changes In The Decades Of 1990–2020, Emiliana Valentini, Serena Sapio, Son V. Nghiem, Seung Hee Kim, Sara Liburdi, Andrea Taramelli

Institute for ECHO Articles and Research

Evapotranspiration (ET) plays a key role in the water cycle and balance, and its estimation is of paramount importance in hydrological studies. This variable is also strongly influenced by the land use and land cover (LULC). This study use a synthesis approach to analyse the relationship between ET variation and LULC transformation in the period 1990–2020. The study area represents a major agricultural region in the Mekong Delta of Vietnam between the Mekong and Bassac rivers. The multivariate dataset was ingested into the hydrological model Soil and Water Assessment Tool to examine the multidecadal ET evolution across the study region. …

Deep Learning-Based Quantification Of Tall Fescue Abundance In Pastures, Rose E. Binkley, Samuel R. Revolinski, Echo Elizabeth Gotsick, Ray Smith, Zeya Wang, Katsutoshi Mizuta

Plant and Soil Sciences Faculty Publications

Accurate and rapid measurement of tall fescue abundance is essential for efficient forage management and mitigating livestock exposure to potential endophyte-related toxicity. Traditional visual estimation methods are labor-intensive and are subject to change depending on the observer doing the calculations, which limits their scalability and consistency. This study explores the application of deep learning techniques to automate and improve the classification of tall fescue abundance across pasture systems in Kentucky. Ground-truth abundance classes were evaluated using one of the traditional methods with occupancy grid and compared against estimates derived from red-green-blue images. Two convolutional neural network architectures, YouOnlyLookOnce (YOLO) and …

Exploring Mesoproterozoic Marine Redox States In A Young Banded Iron Formation From The Needle Mountains, Jaya Sharma, Brenhin Keller

Wetterhahn Science Symposium Posters

Banded iron formations (BIF), as redox-dependent chemical sedimentary rocks, have served as proxies for marine and atmospheric oxygen and iron conditions throughout Earth history. While abundant in the Archean and early Proterozoic, the widespread deposition of BIFs declined following the Great Oxidation Event, as oxygenated surface waters prevented the accumulation of ferrous iron. However, the Needle Mountains, located in southwestern Colorado, houses an anomalously young BIFs deposited between 1.786±10 - 1.801±6 Ga given existing geochronology. Here, we use rare earth element (REE) systematics, bulk chemistry, and petrographic analysis to determine the depositional conditions under which this BIF was formed. We …

Carbon Storage In Headwaters Can Respond Rapidly To Climate Change, Maddie Benello, Carl Renshaw, Joshua Landis

Wetterhahn Science Symposium Posters

Headwater streams play a critical role in the global carbon cycle, serving as significant sites of carbon storage. While there have been recent efforts to quantify carbon storage in headwater streams in the western United States, there remains limited understanding of both the volume and timescale of carbon storage in northeastern forests which often have extensive logging and agricultural histories. Here, we quantify the carbon stock, residence time, and flux of a zero-to-first order headwater stream in Charles Downer State Forest (DF), VT using novel fallout radionuclide (FRN) chronometry. We find DF headwaters have a carbon stock of 66.2 Mg …

Timing, Orbital Pacing, And Provenance Of Late Paleogene Loess In The Western United States, Xiangwei Guo

Earth & Environmental Sciences Dissertations - Archive

This project examines the timing of loess emergence, the nature of the fluvial–eolian transition, orbital forcing on dust accumulation, and sediment recycling in the late Paleogene White River Formation (Group) of Wyoming and Nebraska, western United States. By integrating traditional sedimentology with machine learning–enhanced grain-size analysis, this research shows that loess accumulation at Flagstaff Rim in central Wyoming began during active fluvial deposition at approximately 35.8 Ma, indicating a gradual transition from fluvial to eolian conditions. Machine learning complements field sedimentology and granulometric interpretation while enabling the development of new, testable hypotheses. Extending this framework eastward to Toadstool Geologic Park …

Understanding How Erosion And Unit Thickness Alter The Deformation Of Fold-Thrust Belts, Kaitlyn E. Gallis, Caroline M. Burberry

Nebraska Academy of Sciences: Programs and Proceedings

When a collision of two tectonic plates occurs, fold thrust belts develop, which are widely recognized as the most common mode in which the crust accommodates shortening. Most analog models do not consider erosion when documenting fold thrust belt formation. The lack of experiments on this topic means there are limited consistent studies on the relationship between erosion and deformation. Preliminary experiments suggest that the typical forward breaking thrust sequence is altered by eroding the hinterland, something this experiment series aims to prove or disprove. The new contribution of this work is a systematic evaluation of the variation in initial …

Remediation Impacts Metal Concentrations And Metal Tolerant Bacteria In Soils Of The Missouri Tri-State Mining District, Ophelia R. Pettington

Graduate Theses/Dissertations

After over 100 years of Zn and Pb mining in the Tri-State mining district (TSMD), former mines continue to be sources of metals. Metal contaminated soils can be remediated using plant-microbe interactions. Plants manipulate their microbiome and recruit microbes to increase metal tolerance. Remediating bacteria are site-specific and identifying native microbes can accelerate remediation efforts. Studies relating microbes and metal concentrations in remediated areas in the TSMD are scarce. I collected root and bulk zone soils associated with Andropogon virginicus from remediated and non-remediated sites in Webb City, MO. I used 16S rRNA gene amplicon sequencing to evaluate the bacterial …

Flood-Regime Shifts Across The Lower Midwest, Usa: Identifying Patterns Through Flood Magnitude–Frequency Analysis And Clustering, Kaiser Mostafiz

Graduate Theses/Dissertations

Flood regimes describe how flood behavior changes in magnitude, recurrence, and occurrence through time. Changes in these flood characteristics can affect flood hazards, river systems, infrastructure, and floodplain management. This thesis examines flood-regime change across the Lower Midwest, focusing on Nebraska, Iowa, Kansas, and Missouri from 1961 to 2020. Records from 1,452 U.S. Geological Survey gaging stations were initially compiled, and 208 stations were retained after screening for record availability and analytical consistency. Flood-regime change was evaluated between two 30-year study periods: Period 1 (1961–1990) and Period 2 (1991–2020). The analysis combined Log-Pearson Type III flood-frequency analysis using L-moments in …

A Geospatial Assessment Of Groundwater Salinization In A Multi-Aquifer System: Durango, Mexico, Juan Lopez-Sierra

Graduate Theses/Dissertations

Groundwater salinization poses a critical environmental concern for water resource sustainability in arid and semi-arid regions. This study evaluates spatial and temporal patterns of groundwater salinity across the state of Durango, Mexico, using total dissolved solids (TDS), sodium adsorption ratio (SAR), as salinity indicators and nitrate-nitrogen (NO₃–N) as an anthropogenic indicator. Groundwater quality data were obtained from (CONAGUA), a Mexican water agency. To assess salinity variations with respect to time, while minimizing interannual sampling bias, two multi-year sampling periods were selected: 2012-2013, and 2020-2021. Final datasets consisted of 122 wells for 2012–2013 and 131 wells for 2020–2021. The wells were …

Considerations For Assigned Water After Expiration Of The 2007 Guidelines, Kathryn Sorensen, Sarah Porter, Anne Castle, John Fleck, Eric Kuhn, Jack Schmidt, Katherine Tara

The Traveling Wilburys of the Colorado River

As Colorado River supplies and demands reach razor-thin margins, new tools to provide adaptive capacity will play a critical role in sustaining communities across the West. We must reduce our consumption of water, while finding ways to cushion the impact. One of the most innovative tools for doing this, developed over the last two decades, is “Assigned Water” - giving users the ability to store conserved water earmarked for their own future use. Originally developed as “Intentionally Created Surplus” in the 2007 Colorado River Interim Guidelines, Assigned Water has been revised and expanded through U.S. Mexico Treaty Minutes and as …

Coupling Liquid Chromatography To Orbitrap Isotope Ratio Mass Spectrometry: Overcoming Isotope Effects Of Chromatography And Amount-Dependency By Peak Homogenization, Aoife Canavan, Leonhard Prechtl, Habib Al-Ghoul, Nils Kuhlbusch, Andrea M. Erhardt, Martin Elsner

Earth and Environmental Sciences Faculty Publications

Electrospray ionization Orbitrap mass spectrometry (ESI-Orbitrap-MS) has recently proven to be a powerful tool for compound- and position-specific stable isotope analysis, targeting isotopologues of multiple elements (H, C, N, O, S) in polar analytes. However, studies have so far mainly focused on pure analyte solutions via direct infusion. Here, we present the online coupling of liquid chromatography (LC) to ESI-Orbitrap-MS for stable isotope analysis of sulfamethoxazole (SMX), a synthetic antimicrobial, used as a model compound. Our study explored the fidelity of isotope values with two strategies for capturing and broadening chromatographic peaks after LC. When capturing the target analyte in …

Geoscience Mathematics Self-Efficacy Scale (Geomses) For Majors-Level Undergraduates: Psychometric Data, Michael Coe, Rory Mcfadden, Beth Pratt-Sitaula, Eric Baer

Science Education Resource Center (SERC)

Self-efficacy is often investigated as a key attitudinal component of academic persistence and performance, and self-efficacy surveys can serve in research models as efficient and non-threatening assessment tools to augment or substitute for achievement or performance measures. The Geoscience Mathematics Self-Efficacy Scale (GeoMSES) builds on prior work in measurement of self-efficacy for mathematics by focusing specifically on students’ capacity to apply mathematical skills to typical problems encountered in majors-level undergraduate geoscience courses or in professional geoscience settings. The scale was developed as part of program evaluation research for a set of learning modules designed to augment existing geoscience curricula. In …

Micronutrients (Trace Elements) For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Micronutrient deficiencies can result from removal of agricultural products over many years, changes in soil acidity, or from large increases in plant biomass production and export. This page is specific to high rainfall pastures (more than 600mm average annual rainfall) in the south-west of Western Australia.

The Department of Primary Industries and Regional Development recommends tissue testing to check plant micronutrient nutrient needs.

Potassium For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Potassium (K) deficiency can lead to a decline in clover content and severely limit pasture productivity in high rainfall pastures. Large amounts of potassium can be lost each year through leaching and removal of potassium in hay or silage.

This information is specific to high rainfall pastures receiving more than 600mm average annual rainfall in the south-west of Western Australia.

Soil Sampling High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Soil sampling and testing is an essential part of making good fertiliser decisions. Fertilisers are a large cost to farming pastures in high rainfall areas. This page is specific to sampling high rainfall pastures (more than 600mm average annual rainfall) in the south-west of Western Australia.

The Department of Primary Industries and Regional Development recommends soil sampling and testing as part of a plant nutrient management program.

Sulfur For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Sulfur deficiency can substantially reduce pasture yield on sandy soils, particularly in wet years where the sulfate form of sulfur leaches below the root zone of pasture plants, making it unavailable.

This information applies specifically to high rainfall pastures (over 600mm average annual rainfall) in the south-west of Western Australia.

The Department of Primary Industries and Regional Development recommends basing fertiliser decisions on good evidence (soil and tissue test results)

Tissue Sampling And Analysis For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Tissue testing helps identify nutrient deficiencies that impact plant health. In high rainfall areas ( > 600 mm), pastures are highly productive and have greater demand for both macro- and micronutrients. Micronutrient status is best assessed through plant tissue, as soil levels are difficult to measure accurately.

The Department of Primary Industries and Regional Development recommends tissue testing to assess the effectiveness of fertiliser and soil testing programs, and diagnose emerging macronutrient and micronutrient deficiencies that could cause production losses.

Environmental Impact Of Nitrogen And Phosphorus Fertilisers In High Rainfall Pasture Areas Of Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

The most commonly used nitrogen and phosphorus fertilisers in the high rainfall (>600mm annual average) south-west of Western Australia can be leached into the groundwater and washed into waterways, resulting in serious environmental and economic damage.

The Department of Primary Industries and Regional Development recommends regular soil testing and consultation with FertCare-accredited advisers to reduce leaching losses and increase profit from added nutrients.

A Stable Isotope Comparison Of The Biogenic Carbonate Of Mammalian Tooth Enamel From The Modern Ohio River Valley And Fort Ancient Buffalo Sites, Sara Elizabeth Slack

Theses, Dissertations and Capstones

δ¹⁸O and δ¹³C values change in response to anthropogenic factors (Ghosh & Brand, 2003). Little is known about the effects of anthropogenic climate and land use change on the ecology of the Ohio River Valley. The goal of this research was to quantify the effects of European colonization on the native ecology of the region. The specific questions of this research were: (1) How have mammalian tooth enamel δ¹⁸O and δ¹³C compositions shifted over time within the Ohio River Valley in response to anthropogenic climate change and vegetation? (2) Are there differences …

Nebraska Statewide Groundwater-Level Monitoring Report 2025, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Jeffrey Westrop

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Comparative Assessments Of Methane Flux Measurement Techniques In Serpentinite-Influenced Groundwater Wells, Madison J. Stetson

Open Access Master's Theses

Methane (CH₄₎ emissions from continental serpentinizing systems represent a significant component of Earth’s carbon cycling. Despite increasing recognition of serpentinite-hosted water-rock interactions as a source of trace gases, standardized field methodologies for quantifying trace gas flux from groundwater wells and similar subsurface conduits remain limited. This study addresses that gap by evaluating the reliability and replicability of three chamber-based sampling methods for measuring gas flux in serpentinite-hosted groundwater systems accessed by groundwater monitoring wells. Field measurements were conducted at the Coast Range Ophiolite Microbial Observatory (CROMO) within the McLaughlin Natural Reserve in Lower Lake, California, a site …

Geochemical And Petrological Observations Of The June Lake Basalt, Eastern California, Daniel Jacob Abel

Cal Poly Humboldt theses and projects

The June Lake basalt is a monogenetic cinder cone and 11-km-long lava flow in eastern California located ~10 km NW of the Long Valley caldera. The stratigraphic position of the June Lake basalt between Tahoe and Tioga glacial deposits suggests an eruption age of only ~20-45ka. This age places the June Lake Basalt among the youngest volcanic eruptions in the Long Valley-Mono Basin region, where volcanic activity spans from the late Pliocene to the Holocene. The goal of this study is to use field observations coupled with whole-rock and crystal geochemical analyses to investigate the magma source and pre-eruption magma …

Metamorphosed Components In Cv Chondrites Camel Donga 003 And Camel Donga 040 As Evidence For Varying Degrees Of Metamorphism Within The Parent Body, Kathryn E. Stone

Honors Theses

The CV carbonaceous chondrites are a group of primitive stony meteorites that record early solar-system evolution processes. They are typically of low metamorphic grade, though some metamorphosed CVs have recently been found. Two CV chondrite breccias, Camel Donga 003 (CD 003) and Camel Donga 040 (CD 040) consist of multiple lithologies. CD 003 consists of three lithologies, one of which – Lithology C – has been metamorphosed to petrologic type ~3.7 (Alevy et al. 2025). CD 040 consists of two lithologies, one of which is metamorphosed to petrologic type 3.7 (Dunn and Alevy, 2024; Dunn et al. unpublished). Both samples …

Scanning Electron Microscopy As A Potential Tool For Distinguishing Charcoal From Dark, Oxidized, Biomass, João Vitor Dos Santos, Aleksandar I. Goranov, Lais Gomes Fregolente, Joao Marcos De Lima-Faria, Diego Stefani Teodoro Martinez, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Condensed aromatic carbon (ConAC) is widely used as a proxy for organic materials derived from biomass burning. However, recent evidence shows that ConAC can be also formed through nonpyrogenic oxidative processes. This study presents a proof-of-concept investigation using scanning electron microscopy (SEM) to distinguish charcoal from dark, ConAC-rich materials produced by ambient oxidation of biomass. Pine wood exposed to long-term iron-mediated oxidation was compared with unaltered wood and a controlled laboratory-generated charcoal reference. Conventional geochemical analytical methods, including benzenepoly(carboxylic acid) (BPCA) analysis, Fourier transform–ion cyclotron resonance–mass spectrometry (FT-ICR-MS), solid-state 13C nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis, confirmed substantial …

Co2 Enhanced Oil Recovery In The Dickinson Lodgepole Mounds, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about CO₂ enhanced oil recovery (EOR) in the Dickinson Lodgepole Mounds of Stark County, North Dakota. Includes geological information and how stored CO₂ increases local oil production.

Identification And Characterization Of Tornado Seismic Signals In The Central U.S., Seth Thompson

Theses and Dissertations--Earth and Environmental Sciences

Tornadoes cause extensive property damage and endanger lives. While Doppler radar can indicate the potential for tornado development, it cannot confirm that a tornado is in contact with the ground unless a debris signature is present. While on the ground, a significant amount of a tornado’s energy may be transferred into the earth as seismic vibrations. Thus, seismometers have the potential to detect on-the-ground tornadoes. Since 1960, only five papers have published seismic recordings from tornadoes. These studies have mostly reported on seismic waves generated by tornadoes at a relatively large range, from 0.01-2.5 Hz, representing uncertainty in the dominant …

Soil Organic Carbon And Soil Health Property Responses To Land Management Across Topographic Positions, Mia D. Makovsky

All Graduate Theses, Dissertations, and Other Capstone Projects

uring the last ice age, ice sheets advanced and retreated across the upper Midwest, leaving behind a landscape characterized by poorly drained hummocky topography. Well-aerated soils have formed on uplands and lowlands are dominated by hydric soils. These wetlands and hydric soils have potential to store large quantities of carbon, particularly compared to the well-aerated uplands, but many have been drained and cultivated for decades. Conservation agriculture methods have emerged to protect and conserve soil health from negative effects due to cultivation.The purpose of this study is to determine how agricultural management practices and landscape properties (e.g, topographic position) affect …

Fulbright Project In Iceland In The Summer Of 2026, Irina Filina

Nebraska Academy of Sciences: Programs and Proceedings

This upcoming Fulbright project is inspired by an ongoing debate in the scientific community about the tectonic origin of Iceland. A long-standing theory of Iceland’s formation by excessive magmatism at the Mid-Atlantic spreading center over the well-known hot spot (i.e., oceanic crustal affinity) was recently challenged by the alternative hypothesis that the Icelandic crust is continental in nature and is being stretched and gradually modified by magmatic processes. Based on this hypothesis, a new sunken continent, Icelandia, has been proposed. One of the foundations for the proposed Icelandia is the presence of felsic lavas (indicative of continental flavor in the …

Preliminary Investigation Of The Carbon Storage Potential In The Fort Worth Basin: Reservoir Characterization And Modeling Of The Lower Atoka Grant South Sand In Tarrant County, Texas, Mary Ann M. Moody

Earth & Environmental Sciences Theses

Carbon capture and storage (CCS) is crucial for mitigating atmospheric carbon dioxide (CO₂) emissions that rise from industrial activities. Paleozoic sedimentary basins in Texas are significant reservoirs for hydrocarbon production, and when depleted, show promise for CCS. Long-term reservoir storage suitability requires a multifaceted approach, including site screening and ranking, as well as reservoir characterization, modeling, and simulation. This project first evaluates the CCS potential for the Fort Worth Basin in North Central Texas, then focuses on reservoir characterization of the Lower Atoka Grant South (STH) Sand in Tarrant County and finally assesses the sand’s CO₂ storage …

Modeling Landslide-Generated Tsunami For Hazard Analysis: A Case-Study Of Grewingk, Ak, Cassidy J. Deer

All Master's Theses

Landslide-generated tsunamis pose an increasing hazard in glacial and paraglacial environments, where glacial retreat results in slope instability and the potential for mass movement events into a body of water. This thesis analyzes a landslide–generated tsunami at Grewingk Lake in October 1967 by integrating numerical simulations from the D-Claw and GeoClaw models, which are both derived from the Clawpack framework for solving hyperbolic conservation laws. By modeling landslide dynamics and wave propagation in a coupled manner, this study seeks to improve understanding of the hazard, risks and spatial impact at Grewingk. The D-Claw and GeoClaw modeling approaches complement each other …