Digital Commons Network^™

Hf Radar: Shining A Light On Ocean Currents, Douglas Cahl

Theses and Dissertations

High Frequency (HF) radar systems are commonly used to estimate surface ocean currents over the coastal ocean. Their range depends on their operational frequency and low frequency systems (≤ 10 MHz) can reach distances up to 200 km from the coastline. These systems are used to estimate surface currents by measuring the phase speed of wind-driven waves and comparing the measured speed with that expected theoretically; deviations from the theoretical still-water phase speed are attributed to ocean surface currents. Although HF radar systems are considered a mature technology and the accuracy of the radar-derived surface current estimates is well studied, …

Forecasting Sea Level Rise-Driven Inundation In Diked And Tidally Restricted Coastal Lowlands, K. M. Befus, A. P.D. Kurnizki, K. D. Kroeger, M. J. Eagle, T. P. Smith

Geosciences Faculty Publications and Presentations

Diked and drained coastal lowlands rely on hydraulic and protective infrastructure that may not function as designed in areas with relative sea-level rise. The slow and incremental loss of the hydraulic conditions required for a well-drained system make it difficult to identify if and when the flow structures no longer discharge enough water, especially in tidal settings where two-way flows occur through the dike. We developed and applied a hydraulic mass-balance model to quantify how water levels in the diked and tidally restricted coastal wetlands and water bodies dynamically respond to sea-level rise, specifically applied to the Herring River Estuary …

Detection Of Subsidence In West-Central Florida Using Persistent Scatterer Interferometry And Near-Surface Geophysics, Tonian R. Robinson

USF Tampa Graduate Theses and Dissertations

This dissertation consists of three studies that employ Persistent Scatterer Interferometry (PSI, also known as PSInSAR) to better understand how subsidence in west-central Florida relates to underlying geological processes. In the first study, near-surface geophysical methods (Ground Penetrating Radar (GPR) and Electrical Resistivity (ERT)), terrestrial remote sensing applications (Light Detection and Ranging (LiDAR) and Structure from Motion (SfM)), and PSI were used to monitor the spatial and temporal behaviors of a suspected growing sinkhole in the Sandhill Boyscout Reservation, Hernando County, Florida. The survey area was located within and around a topographic low assumed to be the surface of the …

Ecological Governance Of Aral Sea: Important Way To Deepen Scientific And Technological Cooperation With Central Asia, Miao Wu, Jianfang Qiao, Yuanming Zhang, Changyan Tian, Yaoming Li, Yun Hao, Xiaoyun Zhang, Lixian Wang, Jingjing He

Bulletin of Chinese Academy of Sciences (Chinese Version)

In September 2022, the President of the People’s Republic of China visited Uzbekistan for the first time after the epidemic. In the subsequent joint statement between China and Uzbekistan, China welcomed the adoption of the Aral Sea initiative proposed by Uzbekistan at the General Assembly of the United Nations. The two sides expressed their willingness to actively promote synergy between the Global Development Initiative and projects related to improving the ecological, economic, and social environment of the Aral Sea region under the framework of the United Nations. In this context, this paper describes the current situation of the Aral Sea …

Parameterization Of Cryosat-2 Radar Waveforms Across The Greenland Ice Sheet, Alexander Clark Ronan

Dartmouth College Master’s Theses

Geodetic surface mass balance calculations regularly rely on satellite radar altimeters such as CryoSat-2 to understand elevation and volume changes of the Greenland Ice Sheet (GrIS). However, the impact of changing GrIS shallow subsurface stratigraphic conditions on CryoSat-2 elevation products is poorly understood. We seek to investigate the long-term impacts of changing surface and shallow subsurface conditions on CryoSat-2 Level 2 elevation products derived from the Offset Center of Gravity (OCOG), Ocean - Customer Furnished Item (CFI), and University College London (UCL) Land-Ice retracking algorithms through the analysis of radar waveform characteristics. We further investigate time series from 2010 to …

The Flow Of Power: Addressing Asymmetric Flood Risk In The Upper Valley, Eric Vr Hryniewicz

Geography Undergraduate Senior Theses

Floods are the most damaging natural disasters in America. Land use change in upland watersheds can increase the probability and severity of floods (Bronstert, Niehoff, & Burger, 2002). When watersheds are divided by political and private property boundaries it leads to a misalignment of incentives in which downstream users lack recourse for upstream land use decisions contributing to flood risk. In this thesis, researchers interrogate the attributes of town officials and towns that determine what motivates town governments to act on flooding and what motivates and enables town officials to collaborate on planning and how do they collaborate in practice. …

Preliminary Data Of Potentially Hazardous Radon Concentrations In Modrič Cave (Croatia), Robert Lončarić, Vanja Radolić, Maša Surić, Igor Miklavčić, Matea Šatalić, Dalibor Paar, Lukrecija Obšivač

International Journal of Speleology

Instigated by relatively high cave-air CO₂ concentrations in Modrič Cave (Croatia) recorded for the purpose of speleothem-based paleoclimate research, we established preliminary monitoring of radon (²²²Rn) concentrations within the cave for a 4.5-year period (2018–2022). As radioactive geogenic gas, radon, which often correlates with cave-air CO₂ concentrations, presents a potential health hazard in cases of longer exposure time in high concentration conditions. Since the Modrič Cave is open to tourists and long-term scientific research has been performed within, a safety assessment for radon concentrations was essential. The integrated measurements of radon concentrations were performed by passive …

Reintroducing Hemp (Rongony) In The Material Palette Of Madagascar: A Study On The Potential Of Hemp Clay Components And Its Impact On Social And Ecological Communities., Henintsoa Thierry Andrianambinina

Masters Theses

When mentioning the word hemp, especially in the local language of Madagascar, the literal translation does not set it apart from marijuana, as they are both called “rongony” - creating the stigma around hemp as the negative stereotype of marijuana. However, the material has been used by the ancestors of Madagascar, as well as across cultures, in its fibrous form to produce fabrication like textile goods and packaging. During colonization, the prohibition of hemp intensified, and since then, any activity related to either of these plants is prohibited and will end in severe punitive measures. This thesis explores the strengths …

Unearthing Complexity: Tangible Histories Of Water And Earth, Alexis Violet

Masters Theses

Unearthing Complexity investigates conceptions of time and surface through geological stories of the water and earth. Building on theories of deep time, hydrofeminism, critical zones, and grounding, I hope to foster a deeper awareness of time scales other than our own and a more tangible understanding of the embodied experience of matter in the universe. Working toward a new literacy of the water and earth in which they are recognized as living, changing bodies to which we are inherently tied at a molecular level, the site of this multiscalar inquiry occurs in the coastal zones of the Narragansett Bay where …

Natural And Anthropogenic Factors Affecting The Development Of Two Highland Agricultural Soils Of Bukidnon, Philippines, Guadalupe D. Calalang, Laurent Bock, Gilles Colinet, Vincent Hallet, Peter Walpole

The Philippine Agricultural Scientist

This research was conducted in two highland areas of Bukidnon, Philippines: Miarayon, a sub-catchment of the upper Cagayan de Oro River; and Bendum, a sub-catchment of the upper Pulangui River. Due to their pyroclastic parent rock materials, soils in the upper Cagayan de Oro are classified as Andic Cambisol in open and convex positions, and Andic Umbrisol in concave and depressed positions. Soils in the upper Pulangui are classified as Pisoplinthic Acrisol, Ferralic Nitisol, and Acric Nitisol in areas with ultramafic rock parent materials, and Haplic Cambisol with pyroclastic deposits. Element contents in rocks were congruent to the total soil …

A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo

Dissertations, Theses, and Capstone Projects

Terracotta lamps, known to the Romans as lucernae, are small, handheld, often decorated objects which provided ancient people light. To modern researchers, they serve as tools for dating stratigraphy and iconographic studies. Beyond their immediately apparent aesthetic and symbolic value, the chemical compositions of the clay of these lamps reflect their origin. This study complements archaeological typologies with chemometric analyses to describe 16 Late Republican and Imperial Roman lamps recovered from the villa at Poggio del Molino (PdM), Tuscany. These finds were recovered from the 2021 and 2022 PdM excavations. The combined approach of typology with X-ray Diffraction (XRD) …

Diverged Landscape Of Restaurant Recovery From The Covid-19 Pandemic In The United States, Siqin Wang, Xiao Huang, Bing She, Zhenlong Li

Geosciences Faculty Publications and Presentations

The COVID-19 pandemic has imposed catastrophic impacts on the restaurant industry as a crucial socioeconomic sector that contributes to the global economy. However, the understanding of how the restaurant industry was recovered from COVID-19 remains underexplored. This study constructs a spatially explicit evaluation of the effect of COVID-19 on the restaurant industry in the US, drawing on the attributes of +200,000 restaurants from Yelp and +600 million individual-level restaurant visitations provided by SafeGraph from 1st January 2019 to 31st December 2021. We produce quantitative evidence of lost restaurant visitations and revenue amid the pandemic, the changes in the customers’ origins, …

Toxicological Effects Assessment For Wildlife In The 21st Century: Review Of Current Methods And Recommendations For A Path Forward, Thomas G. Bean, Val R. Beasley, Philippe Berny, Karen M. Eisenreich, John E. Elliott, Margaret L. Eng, Phyllis C. Fuchsman, Mark S. Johnson, Mason D. King, Rafael Mateo, Carolyn B. Meyer, Christopher J. Salice, Barnett A. Rattner

United States Geological Survey: Staff Publications

Model species (e.g., granivorous gamebirds, waterfowl, passerines, domesticated rodents) have been used for decades in guideline laboratory tests to generate survival, growth, and reproductive data for prospective ecological risk assessments (ERAs) for birds and mammals, while officially adopted risk assessment schemes for amphibians and reptiles do not exist. There are recognized shortcomings of current in vivo methods as well as uncertainty around the extent to which species with different life histories (e.g., terrestrial amphibians, reptiles, bats) than these commonly used models are protected by existing ERA frameworks. Approaches other than validating additional animal models for testing are being developed, but …

Microbial Carbon Use Efficiency Promotes Global Soil Carbon Storage, Feng Tao, Yuanyuan Huang, Bruce A. Hungate, Stefano Manzoni, Serita D. Frey, Michael W. I. Schmidt, Markus Reichstein, Nuno Carvalhais, Philippe Ciais, Lifen Jiang, Johannes Lehmann, Ying-Ping Wang, Benjamin Z. Houlton, Bernhard Ahrens, Umakant Mishra, Gustaf Hugelius, Toby D. Hocking, Xingjie Lu, Zheng Shi, Kostiantyn Viatkin, Ronald Vargas, Yusuf Yigini, Christian Omuto, Ashish A. Malik, Guillermo Peralta, Rosa Cuevas-Corona, Luciano E. Di Paolo, Isabel Luotto, Cuijuan Liao, Yi-Shuang Liang, Vinisa S. Saynes, Xiaomeng Huang, Yiqi Luo

Faculty Publications

Soils store more carbon than other terrestrial ecosystems1,2. How soil organic carbon (SOC) forms and persists remains uncertain1,3, which makes it challenging to understand how it will respond to climatic change3,4. It has been suggested that soil microorganisms play an important role in SOC formation, preservation and loss5,6,7. Although microorganisms affect the accumulation and loss of soil organic matter through many pathways4,6,8,9,10,11, microbial carbon use efficiency (CUE) is an integrative metric that can capture the balance of these processes12,13. Although CUE has the potential to act as a predictor of variation in SOC storage, the role of CUE in SOC …

Structural Relationships Across The Sevier Gravity Slide Of Southwest Utah And Implications For Catastrophic Translation And Emplacement Processes Of Long Runout Landslides, Michael J. Braunagel, William Ashley Griffith, Robert F. Biek, David B. Hacker, Peter D. Rowley, David H. Malone, Danika Mayback, Tiffany A. Rivera, Zachary Loffer, Zachary D. Smith

Faculty Publications - Geography, Geology, and the Environment

The physical processes that facilitate long-distance translation of large-volume gravity slides remain poorly understood. To better understand these processes and the controls on runout distance, we conducted an outcrop and microstructural characterization of the Sevier gravity slide across the former land surface and summarize findings of four key sites. The Sevier gravity slide is the oldest of three mega-scale (>1,000 km2) collapse events of the Marysvale volcanic field (Utah, USA). Field observations of intense deformation, clastic dikes, pseudotachylyte, and consistency of kinematic indicators support the interpretation of rapid emplacement during a single event. Furthermore, clastic dikes and characteristics of …

Estimating Snow Accumulation And Ablation With L-Band Interferometric Synthetic Aperture Radar (Insar), Jack Tarricone, Ryan W. Webb, Hans-Peter Marshall, Anne W. Nolin, Franz J. Meyer

Geosciences Faculty Publications and Presentations

Snow is a critical water resource for the western United States and many regions across the globe. However, our ability to accurately measure and monitor changes in snow mass from satellite remote sensing, specifically its water equivalent, remains a challenge. To confront these challenges, NASA initiated the SnowEx program, a multiyear effort to address knowledge gaps in snow remote sensing. During SnowEx 2020, the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) team acquired an L-band interferometric synthetic aperture radar (InSAR) data time series to evaluate the capabilities and limitations of repeat-pass L-band InSAR for tracking changes in snow water equivalent …

Evaluating The Relationship Between Methane Seeps And Seafloor Geomorphology On The Northern Us Atlantic Margin, Gabriel Hernandez

Theses and Dissertations

Methane seeps are a transport pathway for carbon from seafloor sediments to the marine environment with important implications for global biogeochemical cycling. Accordingly, there is substantial interest in better understanding the processes that control seep location and predicting the distribution of seeps with existing seafloor datasets. Visual evaluation of methane seeps, in multibeam sonar water column data, suggests a spatial relationship between seeps and specific seafloor morphologic features such as ridge crests. In this thesis, seafloor geomorphology at 1996 seep detection sites on the US Atlantic margin was quantitatively characterized by geomorphologic phonotype, bathymetric position index, slope, rugosity, and aspect …

Occurrence Of Radionuclides And Hazardous Elements In The Transboundary River Basin Kyrgyzstan–Kazakhstan, Mariya A. Severinenko, Vladimir P. Solodukhin, Bekmamat M. Djenbaev, The National Academy Of Science Of The Kyrgyz Republic G. Lennik, Baktiyar T. Zholboldiev, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Important for irrigation, the transboundary river basin between Kyrgyzstan and Kazakhstan is vulnerable to geochemical and anthropogenic sources of pollution. The use of water use indices, together with measurements of the elemental and radionuclide composition of the water and bottom sediments, provides a means for evaluating the continued use of the water from this region. Recent monitoring shows the highest concentrations of hazardous contaminants include lead and thorium contained in the bottom and banks of the Kichi-Kemin River. These contaminants are likely remnants of an accidental spill at the Aktyuz tailing dump in 1964. The specific activity of the Th-232 …

New Insights Into The Paleovegetation Of The Ancient Underwater Forest Located In The Northern Gulf Of Mexico, Karla Lizarraga Garcia

Master's Theses

A well-preserved remnant of an ancient bald cypress forest (hereafter, Underwater Forest) constitutes the only known archive of a glacial refuge on the once exposed continental shelf of the Northern Gulf of Mexico. This forest existed around 41-72 yBP (MIS 3-5) according to the existing dating methods applied on previous studies. As the climate conditions and sea levels changed, the vegetation of this glacial refuge shifted from bald cypress forests to open marshes, altering the vegetation dynamics. The present research analyzed four new cores (21DF-5A, 21DF-5B, 15DF-6, and 16DF-3A), which provided additional insights into the vegetation that once existed in …

Fault Influence On Castle Mesa Fracture Node Pattern, Kaitlin Steinauer

Theses/Capstones/Creative Projects

Fracture nodes are useful in determining the connectivity of a fracture pattern which is important when considering hydrogeological and mechanical behavior of a rock. Four node types are used to describe the pattern, including isolated (I), perpendicular abutting (T), low-angle abutting (Y), and cross-cutting (X). Faults can affect a fracture pattern by creating a highly fractured zone in their vicinity. I investigate the Moab Tongue Member of the Entrada Formation at Castle Mesa in Moab, Utah to determine a) how the percentage of different node types changes with distance from the fault, b) any difference in node type proportions between …

Seeing The Forest And The Trees: Holistic View Of Social Distancing On The Spread Of Covid-19 In China, Danlin Yu, Yaojun Zhang, Jun Meng, Xiaoxi Wang, Linfeng He, Meng Jia, Jie Ouyang, Yu Han, Ge Zhang, Yao Lu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The human social and behavioral activities play significant roles in the spread of COVID-19. Social-distancing centered non-pharmaceutical interventions (NPIs) are the best strategies to curb the spread of COVID-19 prior to an effective pharmaceutical or vaccine solution. This study investigates various social-distancing measures’ impact on the spread of COVID-19 using advanced global and novel local geospatial techniques. Social distancing measures are acquired through website analysis, document text analysis, and other big data extraction strategies. A spatial panel regression model and a newly proposed geographically weighted panel regression model are applied to investigate the global and local relationships between the spread …

Urban & Deltaic Subsidence In Bangladesh From Sentinel-1 Insar Data Analysis, Gavin Middleton

Masters Theses & Specialist Projects

Bangladesh's Bengal Delta faces multiple challenges, such as rising sea levels, coastal flooding, and high population density, leading to land subsidence, saltwater intrusion, and biodiversity loss. The region's groundwater security, essential for the country's survival, is at risk due to climate change and saltwater intrusion. Groundwater security is dependent on the Bengal Water Machine (BWM), which is at risk due to saltwater intrusion and monsoon rainfall distribution from climate change. Groundwater exhaustion leads to natural hazards such as subsidence, landslides, and flooding. A large portion of the population is at risk from groundwater insecurity, which requires mitigating worldwide greenhouse gas …

Net-Zero Target And Emissions From Land Conversions: A Case Study Of Maryland's Climate Solutions Now Act, Philip Hutton

All Theses

Many climate change “solution” plans include net-zero goals, which involve balancing the anthropogenic greenhouse gas emissions (GHG) with their removal. Achieving net-zero goals is particularly problematic for soils because they are often excluded from GHG inventories and reduction plans. For example, Maryland’s Climate Solutions Now Act (Senate Bill 528) put forward a target of net-zero emissions by 2045. To achieve these goals, the state of Maryland (MD) needs to quantify GHG emissions. Soils are currently excluded from MD’s GHG assessments. This study examines the challenges in meeting net-zero goals by using carbon dioxide (CO₂). The current study quantified …

The Terroir Of Swiss Cheese: A Temporal And Geomorphological Investigation Of The Martian Co2 Sublimation Pits, Racine D. Cleveland

Graduate Theses and Dissertations

Observations by NASA Mars Global Surveyor showed evidence of rough topography on the South Pole of Mars. The topography is the result of CO2 sublimation processes that occur through the changing seasons on the red planet. These sublimation areas are known to scientists as Swiss Cheese Features (SCF). SCF are erosional degradation pits that have been studied for over two decades. Studies show that these SCF increase in area over time, but these values are collected by hand on a per feature basis. Models for the pit evolution have also played a part in understanding these SCF. This work is …

The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford

Theses/Capstones/Creative Projects

This study assesses chemical weathering trends as they relate to glacial retreat. The chemical environment of surfaces exposed to the atmosphere differs significantly from beneath a glacier. As a glacier melts, changes to the biogeochemical processes generate environmental gradients. This study analyzed chemical weathering signals at different distances from a glacial front by comparing the elemental composition of leachate derived from sediments in southeastern Greenland. Samples from proglacial, nonglacial, and moraine locations were weathered in a laboratory setting, and ion chromatography was used to determine the elemental composition of the products. Divergent trends in leachate composition were observed as distance …

College Of Natural Sciences Newsletter, March - May 2023, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 4, Issue 2

Page 1 Dean's Message
Page 2-7 Awards and Recognition
Page 8 March 3rd Corothers Seminar
Page 9 54th Geography Convention
Page 10 Spring 2023 Day of Scholars
Page 11 2023 URSCAD Snaps
Page 12-14 Media Coverage of CNS
Page 15 Open PRAIRIE Data

Glacialwater: A Dynamic Microbial Medium, Gilda Varliero, Pedro H. Lebre, Andrew G. Fountain, Beat Frey, Alexandre M. Anesio, Don A. Cowan

Geology Faculty Publications and Presentations

Microbial communities and nutrient dynamics in glaciers and ice sheets continuously change as the hydrological conditions within and on the ice change. Glaciers and ice sheets can be considered bioreactors as microbiomes transform nutrients that enter these icy systems and alter the meltwater chemistry. Global warming is increasing meltwater discharge, affecting nutrient and cell export, and altering proglacial systems. In this review, we integrate the current understanding of glacial hydrology, microbial activity, and nutrient and carbon dynamics to highlight their interdependence and variability on daily and seasonal time scales, as well as their impact on proglacial environments.

Critical Metals: From Granitic Pegmatites To The Anthropogenic Cycle, Dalton Mccaffrey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Critical metals are vital to the functionality of the modern world. The increased diversity and usage intensity of these commodities in defense-related and strategic technologies (e.g., jet engines, rocket assemblies), modern infrastructure and products (e.g., high-strength steel, cellular phones, laptop computers), and energy-related, low-emissions technologies (e.g., nuclear reactors, solar panels, wind turbines, hybrid and electric vehicles) has drastically increased our reliance on critical metals and, thus, the United States (and global) exposure to supply restrictions. Granitic pegmatites are unique mineral deposits that represent a past, present and future resource for many (approximately half) of these critical resources. Even with the …

Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder

Theses and Dissertations

Air pollution is a substantial environmental challenge all over the world. This study investigated the long-term air pollution levels in the Lower Rio Grande Valley region, by utilizing data collected from five continuous ambient monitoring stations in two counties over 23 years, from January 2000 to December 2022, to analyze daily, monthly, and seasonal variations of different pollutants, including ground-level ozone, particulate matter, and carbon monoxide. This study also identified distinct daily and seasonal patterns for O3, PM2.5, PM10, and CO at each monitoring site, influenced by factors such as traffic emissions, temperature, solar radiation, indoor heating, and weather conditions. …

New Reports Of Smilodon And Panthera From North American Cave Sites With Reviews Of Taxonomy, Biogeography, And History, Matthew Bushell

Electronic Theses and Dissertations

In this study, three new reports of large felids from the Pleistocene are presented and discussed. A single partial left dentary from Jawbone Cave represents the first confirmed presence of S. fatalis in east Tennessee and was sampled for radiocarbon dating. Wind Tunnel and Chilly Bowl Cave are among the first records of P. onca to be identified confidently from Arkansas. Chilly Bowl Cave also produced two trackways attributable to Panthera sp., one set potentially belonging to P. atrox. In addition to the description of these remains and the caves they were found in, taxonomic histories for both S. fatalis …