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Full-Text Articles in Earth Sciences

Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck May 2024

Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck

Student Research Symposium

The Mahogany Mountain-Three Fingers Rhyolite Field (MM-TFrf) in southeastern Oregon, associated with mid-Miocene rhyolite activity and Columbia River flood basalts, has been the subject of geological scrutiny. Previous studies proposed separate origins for the tuff of Leslie Gulch (LGT) and Spring Creek, but Benson and Mahood (2006) suggested a single ignimbrite event at 15.8 Ma, prompting a reassessment of MM-TFrf's history. This research focuses on LGT, investigating textural disparities between welded and non-welded tuff formations. Petrographic examinations delve into the transformation stages of pyroclastic tuff deposition, revealing the dynamic influences of volcanological and magmatic processes on welded and non-welded tuff …


Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan May 2024

Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan

Student Research Symposium

As the Pacific Northwest climate changes, extreme weather, such as intensifying storms, and a shift in the type of precipitation experienced with warmer winters causing more precipitation to fall as rain instead of snow, may lead to an increased frequency of landslides. There have been several recent landslides in Portland, noticeable to the public, particularly in areas of high elevation such as Council Crest, which stands at 1,073 feet. Additionally, residents of neighboring homes have observed changes in the landscape, including those on private properties. To better safeguard both public and private property, comprehensive research and mitigation efforts are required. …


Controls On Soft Tissue And Cellular Preservation In Late Eocene And Oligocene Vertebrate Fossils From The White River And Arikaree Groups Of Nebraska, South Dakota, And Wyoming, John E. Gallucci, Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, Dennis O. Terry May 2024

Controls On Soft Tissue And Cellular Preservation In Late Eocene And Oligocene Vertebrate Fossils From The White River And Arikaree Groups Of Nebraska, South Dakota, And Wyoming, John E. Gallucci, Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, Dennis O. Terry

School of Earth & Environment Departmental Research

Previous studies on microtaphonomy have identified multiple types of organic microstructures in fossil vertebrates from a variety of time periods and past environmental settings. This study investigates potential taphonomic, paleoenvironmental, and paleoclimatic controls on soft tissue and cellular preservation in fossil bone. To this end, fifteen vertebrate fossils were studied: eight fossils collected from the Oligocene Sharps Formation of the Arikaree Group in Badlands National Park, South Dakota, and seven fossils from formations in the underlying White River Group, including the Oligocene Brule Formation of Badlands National Park, and the Eocene Chadron Formation of Flagstaff Rim, Wyoming; Toadstool Geologic Park, …


Reactivity Of Adsorbed Trace Metals At Metal (Oxyhydr)Oxide Surfaces As Probed With Isotope Exchange, Greg Ledingham May 2024

Reactivity Of Adsorbed Trace Metals At Metal (Oxyhydr)Oxide Surfaces As Probed With Isotope Exchange, Greg Ledingham

Arts & Sciences Graduate Student Theses and Dissertations

Metal (oxyhydr)oxide surfaces regulate the accessibility of trace metals in soils and aquatic systems. Up to half of the trace metals in urban environments, river systems, and contaminated soils are associated with mineral surfaces yet this pool often remains bioaccessible. Past studies of adsorption-desorption suggest that macroscopic rates of adsorption at mineral surfaces are likely mass transfer-limited and show biphasic rates, with a fast-adsorbing fraction equilibrating in seconds to minutes and a slower-adsorbing pool binding over a timescale of hours to days. In addition, adsorption-desorption hysteresis has been observed for some metals after aging at metal (oxyhydr)oxide surfaces, indicating that …


Effects Of Urbanization On Eutrophication Parameters In Three Tidal Creeks, Ella Swantek May 2024

Effects Of Urbanization On Eutrophication Parameters In Three Tidal Creeks, Ella Swantek

Honors Theses

Marshes and swashes are vital environments as a controlling barrier between land affected by various pollutants and the ocean. Eutrophication and the effects of this process can be detrimental for the areas experiencing it. I am interested in ways areas that have little contact with human interactions compare to areas that are heavily urbanized, and whether either of these locations is at a higher risk for eutrophication. Using spectrophotometry and fluorometry, I analyzed samples collected from the relatively undeveloped and restricted-access locations of Waities Island Beach and Dunn Sound monthly for dissolved nutrients, and chlorophyll. At the time of sampling, …


Gis Analysis Application Of Flood Risk Map In Beijing, China, Yuxuan Liu May 2024

Gis Analysis Application Of Flood Risk Map In Beijing, China, Yuxuan Liu

Honors Capstones

From the end of July to the beginning of August 2023, Beijing, China, affected by Typhoon "Dusuri" experienced the most precipitation in the Beijing area in 140 years of instrument measurement records. This event led to the evacuation of more than 1.8 million people across the Beijing-Tianjin-Hebei region and the tragic loss of 62 lives. After experiencing such fierce heavy rainfall and flood disasters, how to predict and prepare for such catastrophic events and avoid losses in the future has become a crucial problem. Geographic information systems (GIS) can integrate different layers of geospatial information and provide us with powerful …


Impacts Of Hurricane Idalia’S Surge On Coastal Sand Biogeochemistry, Wendy "Cor" Mchone May 2024

Impacts Of Hurricane Idalia’S Surge On Coastal Sand Biogeochemistry, Wendy "Cor" Mchone

Honors Theses

Beaches are heavily influenced by extreme events, such as hurricanes. Biological and chemical processes, such as primary production and diagenesis are often interrupted by these events. To examine the effects of hurricanes on coastal biogeochemistry, this study used sand and porewater samples from Waties Island, SC, which were collected before and after Hurricane Idalia. The samples were analyzed for macronutrient concentrations, organic content, and chlorophyll concentrations. Macronutrient pore water concentration changes were not uniform. The inventory of nitrite decreased significantly after the storm, which was reflected in slight increases in the inventories of nitrate and ammonium. Concentrations of nitrate, which …


Sedimentary Conditions At A Tidal Creek That Exhibits Seasonal Pelagic-Benthic Variations, Jack B. Corbin May 2024

Sedimentary Conditions At A Tidal Creek That Exhibits Seasonal Pelagic-Benthic Variations, Jack B. Corbin

Honors Theses

Tidal creeks in the Grand Strand of South Carolina are small but numerous connectors between land and ocean. One of these creeks, White Point Swash, exhibits a seasonal switch between planktonic and benthic photosynthesizers. As plankton become less abundant in fall, benthic macroalgae bloom, aided by lower water levels due to fall-winter dredging of the main channel, until late Spring. This study builds on previous findings and examines sedimentary conditions at this site further. Sedimentary chlorophyll a (in microphytobenthos) and pore water nutrient concentrations are confirmed to be higher than water-column concentrations. Sedimentary nutrient fluxes to the sediment-water interface, calculated …


Investigating The Drought Sensitivity Of Intermontane-Basin Groundwater Systems In Western Montana Using Standardized Drought Indices, Daniel Buckley May 2024

Investigating The Drought Sensitivity Of Intermontane-Basin Groundwater Systems In Western Montana Using Standardized Drought Indices, Daniel Buckley

Graduate Theses & Non-Theses

Drought is a worldwide phenomenon, and many metrics have been developed to help monitor and understand drought. In this study, the drought sensitivity of two different western Montana intermontane-basin groundwater systems were analyzed: the Bitterroot Valley and the Gallatin Valley. Different standardized meteorological drought indices, namely, the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI), were compared against the Standardized Groundwater level Index (SGI) to better understand groundwater sensitivity to meteorological forcing. The SPI and SPEI were computed using precipitation and reference evapotranspiration data from the gridMET dataset. Groundwater level data from the Montana Bureau of Mines …


Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys May 2024

Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys

Graduate Theses & Non-Theses

In this study, stress and strain measurements from unconfined compression tests were used to determine the peak stress, yield stress, Young’s modulus, and Poisson’s ratio of 20 specimens representing three lithologies (sandstone, norite, and argillite-quartzite mix) from Idaho and Montana. Along with traditional strength and deformation parameters, crack initiation (CI) and crack damage (CD) values were also interpreted, corresponding to the stress levels associated with the formation and coalescence of microcracks as a specimen is exposed to increasing stress levels. Acoustic emissions (AE) data were collected along with traditional stress-strain data as this has become a popular method for interpreting …


Glacier Lake Inventory And Lake Outburst Flood Hazard Assessment In Kanchenjunga Conservation Area, Nepal, Prabish Khadka Chhetri May 2024

Glacier Lake Inventory And Lake Outburst Flood Hazard Assessment In Kanchenjunga Conservation Area, Nepal, Prabish Khadka Chhetri

Theses

This study presents a comprehensive assessment of glacial lakes and land surface temperature (LST) dynamics within the Kanchenjunga Conservation Area (KCA) from 2010 to 2023. The KCA holds significant ecological importance, serving as a critical habitat for diverse flora and fauna, while also playing a vital role in regional hydrological systems. Additionally, its stunning landscapes attract tourists and mountaineers from around the world, further emphasizing the need for understanding environmental changes within the area. Utilizing medium to high-resolution satellite imagery from PlanetScope for glacial mapping and Landsat for LST analysis, the research aimed to achieve two primary objectives: creating an …


The Morphology, Spatial Distribution, And Collapse Mechanisms Of Volcanoes On Venus, Rebecca Mary Hahn May 2024

The Morphology, Spatial Distribution, And Collapse Mechanisms Of Volcanoes On Venus, Rebecca Mary Hahn

Arts & Sciences Graduate Student Theses and Dissertations

Radar imagery collected by NASA’s Magellan spacecraft enabled the recognition and classification of volcanic features and structures across Venus far beyond the scope of earlier missions. These datasets revealed volcanoes that range in size from <5 km to well over 100 km in diameter. Volcanism is clearly a major, widespread process on Venus, and is a principle expression of the planet’s secular loss of interior heat. For my doctoral work, I utilized ESRI’s ArcMap and ArcGIS Pro to develop a detailed global catalog of volcanoes across Venus to improve our understanding of the morphology, spatial, distribution, and evolution of volcanism on the second planet. Chapter 2 introduces the creation and implementation of my global catalog of volcanoes and volcanic fields on Venus. This new global dataset includes ∼85,000 edifices, ∼99% of which are <5 km in diameter and are geographically widespread across the entire planet. With this catalog, I developed an automated approach to delineating volcanic fields—high spatial concentrations of small volcanoes—and also noted a dearth of volcanoes 20–100 km in diameter, which could be related to the eruption rate and/or availability of the underlying magma supply. Chapter 3 focuses on a unique subset of 162 volcanoes on Venus that appear to have undergone gravitational deformation. These deformed edifices are distributed globally, are situated at a range of elevations, are spatially proximal to a variety of tectonic structures, and are associated with various crustal thickness values, which together suggest that there are numerous drivers of volcano deformation on Venus. Furthermore, I note examples of flank terraces on Tepev Mons, a structural indicator of volcano sagging that has not yet been documented on Venus. Lastly, Chapter 4 employs kernel density estimation as a tool at nine topographic rises, and nine volcanic fields across Venus to delineate regions where future volcano formation could occur, based on the locations of edifices ≤20 km in diameter from our global catalog developed in Chapter 2. These resulting volcano-formation probability maps reveal that the intensity of volcanism producing volcanoes ≤20 km in diameter in the Beta-Atla-Themis (BAT) region, an area well-known for its enhanced volcanism (Airey et al., 2017), is lower than at topographic rises across the rest of the planet. These maps can also be used to identify specific regions across Venus that future missions such as EnVision and VERITAS can image using their higher-resolution radars and thus search for newly formed volcanoes between the time of those missions and when the Venus surface was originally mapped by Magellan. Based on my analysis, I conclude that these missions should target specific regions of high-volcano-spatial density in and around Atla, Imdr, Themis, and Dione Regiones.


Characterizing Potentially Harmful Environmental Legacy Issues Within A Declining Midwest City: A Street Sediment Study Of Northeastern Terre Haute, Indiana, Katelyn Adams '24, Ken Brown May 2024

Characterizing Potentially Harmful Environmental Legacy Issues Within A Declining Midwest City: A Street Sediment Study Of Northeastern Terre Haute, Indiana, Katelyn Adams '24, Ken Brown

Senior Scholarly and Creative Symposium

Urban settings face unprecedented environmental challenges that include legacy issues as well as emerging pollution problems (e.g., micro-plastics) that continually impact the public health of its communities. Determining the baseline abundances of potentially harmful contaminants in soil, sediment, air, and water is essential to protecting residents. This study examines anthropogenic pollution in street sediments collected from three neighborhoods located in northeast Terre Haute, Indiana. Using stereomicroscopy, SEM/EDS, pXRF analyses, and geospatial analysis (GIS), the goal of this work is to characterize the types of pollutants present and place important constraints on their potential sources.

Stereomicroscopy on nine street sediment samples …


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

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

Senior Scholarly and Creative 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 …


Pre-Plinian Perplexity: Identifying And Constraining An Anomalous Pdc During The Initial Stages Of The May 18, 1980 Mt. St. Helens Eruption, Justin Crevier May 2024

Pre-Plinian Perplexity: Identifying And Constraining An Anomalous Pdc During The Initial Stages Of The May 18, 1980 Mt. St. Helens Eruption, Justin Crevier

Geosciences Undergraduate Theses

The Mount St. Helens (MSH) 18 May 1980 eruption was a formative event for a generation of volcanologists. With so much data available from detailed studies of the Blast and Plinian phases, MSH could aptly be called one of volcanology's greatest teachers—and the volcano may yet have more to teach us. The transition period, which occurred between the end of the Blast phase (0830) and the beginning of the Plinian phase (0920) on the morning of May 18, 1980, has not yet benefited from the same degree of comprehensive review as either of those phases. The conditions which caused the …


Machine Learning And Geostatistical Approaches For Discovery Of Weather And Climate Events Related To El Niño Phenomena, Sachi Perera May 2024

Machine Learning And Geostatistical Approaches For Discovery Of Weather And Climate Events Related To El Niño Phenomena, Sachi Perera

Computational and Data Sciences (PhD) Dissertations

El Nino and La Nina are worldwide environmental phenomena brought about by repetitive changes in the water temperature of the Pacific Ocean. Even though the El-Nino impact focuses on a smaller area in the Pacific Ocean near the Equator, these developments have global repercussions, where temperature and precipitation are influenced across the globe, causing droughts and floods simultaneously. In this dissertation, we first derived a drought vulnerability index for the Nile basin, identifying regions with high and low drought risk under ENSO conditions. Next, we evaluated the coherence and periodicity of the ENSO signal to detect its implications on MENA …


Settler Colonialism And Ecosystem Change: How Ideology Has Shaped Minnesota’S Environments, Sarah E. Hobby May 2024

Settler Colonialism And Ecosystem Change: How Ideology Has Shaped Minnesota’S Environments, Sarah E. Hobby

History Honors Projects

The formation of a uniquely American land ethic—defined by European political history and Christian biblical doctrine and forged through systems of dispossession—is central to the creation of environments within the United States today. Using Minnesota as a microcosm to understand how settler colonial interactions played out all across the United States, this paper analyzes connections between violent dispossession of Indigenous people and the degradation of environments. By understanding how Ojibwe and Dakota people think about and have shaped Minnesotan lands throughout their history and comparing Indigenous land-ethics to the Euro-American-settler land ethic, this paper evaluates the role that ideology and …


Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre May 2024

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 …


Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti May 2024

Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti

All Graduate Theses and Dissertations, Fall 2023 to Present

Growing nursery plants in containers requires a timely supply of mineral nutrients for optimum growth. However, there is a misconception among growers that the application of higher doses of fertilizers hastens plant growth; instead, it can lead to runoff and leaching loss of nutrients. Reducing fertilizer application while sustaining healthy plants can not only negate environmental consequences but also save fertilizer costs. For example, two ground covers, Lysimachia nummularia (creeping jenny, moneywort) and Vinca minor 'Bowles' (periwinkle), can be grown for three months by applying 6 mg/L of phosphorus (P) as reduction of P to single application of 6 mg/L …


Descriptions Of Interglacial Mastodons From Snowmass, Colorado, Connor White May 2024

Descriptions Of Interglacial Mastodons From Snowmass, Colorado, Connor White

Electronic Theses and Dissertations

The Ziegler Reservoir fossil site (ZRFS) in Colorado contains over 4000 mastodon bones that date from 140,000 to 100,000 years ago. At an elevation of ~2705 meters above sea level, ZRFS represents an alpine ecosystem dated to Marine Isotope Stage (MIS) 5. Formal descriptions of cheek teeth, mandibles, crania, and femora were completed. Statistical analyses of the upper and lower third molars, including a novel measurement of interloph(id) distances, indicate significant differences between ZRFS mastodons and Mammut pacificus, while falling within the ranges for Mammut americanum. This study agrees with the taxonomic assignment of ZRFS mastodons to Mammut …


The Olmsted Fault, Southernmost Illinois: A Key To Understanding Seismic Hazard In The Northern New Madrid Seismic Zone, Christopher E. Bexfield May 2024

The Olmsted Fault, Southernmost Illinois: A Key To Understanding Seismic Hazard In The Northern New Madrid Seismic Zone, Christopher E. Bexfield

Theses and Dissertations

The northernmost extent of the New Madrid seismic zone in the central USA has been investigated using an integrated approach involving both compressional-wave (P) and horizontally polarized-wave (SH) seismic reflection and regional and dedicated borehole geophysical information in order to assess seismic hazard and risk. Our study area, centered around southernmost Illinois and western Kentucky, USA, represents an area of concentrated facilities (e.g., lock and dam sites and chemical plants on the Ohio River near its confluence with the Mississippi River) as well as an area of high potential soil amplification due to earthquake shaking. Integrated high-resolution seismic reflection profiles …


Free And Forced Vibrations Of Elastically Restrained Cantilever With Lumped Oscillator, Alireza Babaei, Johné Parker, Paria Moshaver May 2024

Free And Forced Vibrations Of Elastically Restrained Cantilever With Lumped Oscillator, Alireza Babaei, Johné Parker, Paria Moshaver

Earth and Environmental Sciences Faculty Publications

The efficiency assessment of cantilever-based energy harvesters relies on vibrational analysis, which necessitates modi- fications aimed at enhancing efficiency. These modifications involve manipulating the fundamental frequency to lower values and encompassing a wider range of resonances within a specified bandwidth. Consequently, this paper introduces an original analytical-numerical exploration into the vibratory response of a cantilever with a novel boundary condi- tion involving an elastically restrained oscillator-spring arrangement. At the microbeam’s tip, an oscillator is elastically confined by a linear spring, resulting in a novel set of coupled governing equations and a distinct shearing boundary condition. Microbeam equations is derived from …


Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo May 2024

Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo

Geology Faculty Publications and Presentations

Volcanic glass has been used extensively as a paleoaltimeter. Deuterium (2H) concentrations in glass have been found to be stable over geologic timescales, making δ2H (also known as δD) a reliable proxy for ancient water chemistry. However, continued work revolves around better understanding how different factors affect preserved water in volcanic ash. Here, we analyze δD in the Rattlesnake Tuff (RST), a widespread ca. 7 Ma ash-flow tuff, and create a paleoisoscape to assess variations in δD across Oregon during that time. To this end, 16 ash samples were collected across central and eastern Oregon from …


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

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 …


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

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 Global Analysis Of Carbon And Nitrogen Stocks In Natural And Anthropogenic Soils, Shih-Chieh Chien May 2024

A Global Analysis Of Carbon And Nitrogen Stocks In Natural And Anthropogenic Soils, Shih-Chieh Chien

Theses, Dissertations and Culminating Projects

In terrestrial biomes, soils possess the highest amount of carbon and nitrogen stocks that regulate biogeochemical processes and provide ecosystem services. The amount of carbon and nitrogen stored in soils, as a balance of nutrient influxes and outfluxes, is controlled by various environmental and soil factors, while at the same time soil carbon and nitrogen stocks can be subject to anthropogenic impacts, like nutrient storage in urban soils. To inform a better, general understanding of carbon and nitrogen distribution in urban soils, the present dissertation gathers four articles (from Chapters 2 to 5, respectively) addressing different aspects of the issue, …


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

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 …


The Effect Of Agrivoltaics On Irrigation Water Consumption In Central California, London Camba May 2024

The Effect Of Agrivoltaics On Irrigation Water Consumption In Central California, London Camba

Undergraduate Theses

An agricultural system where solar energy generation and agricultural systems are used together for mutual benefit, agrivoltaics reduces loss of water due to evaporation, particularly in drylands. Central California has faced extreme droughts, and water has become a scarce resource. However, the wide-scale use of agrivoltaics has been limited due to lack of knowledge about agrivoltaics and also the lack of funding for start-up agrivoltaics projects. Therefore, this research investigated the potential for agrivoltaics in Central California to reduce irrigation water consumption using a review of multiple crop studies using agrivoltaics to determine an optimal crop for agrivoltaics and a …


Using Strainmeters To Characterize Enhanced Geothermal Systems, Clem Laffaille May 2024

Using Strainmeters To Characterize Enhanced Geothermal Systems, Clem Laffaille

All Theses

none


Coastal-Ocean And Estuarine Acidification In Long Bay, South Carolina: A Comparison Of In-Situ Water Quality Monitoring With Measured Carbonate System Parameters, Mary Olsen May 2024

Coastal-Ocean And Estuarine Acidification In Long Bay, South Carolina: A Comparison Of In-Situ Water Quality Monitoring With Measured Carbonate System Parameters, Mary Olsen

Electronic Theses and Dissertations

One of the major water-quality issues impacting our coast and estuaries is coastal-ocean and estuarine acidification. Due to a relative dearth of data in the southeastern United States it is increasingly difficult to determine the full extent and intensity of this problem. This study provides the first characterization of coastal-ocean and estuarine acidification in Long Bay, SC by attempting to leverage long-term water quality data sets at two coastal-ocean pier sites using in-situ YSI EXO sondes deployed at both the surface and bottom waters along with two estuarine sites sampled by volunteer monitors using Orion star multi-meters. Discrete samples (120) …