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Post-Wildfire Effects On A Headwater Stream In The San Bernardino National Forest, Kelley Giron

Electronic Theses, Projects, and Dissertations

Southern California has experienced prolonged drought conditions that have supported frequent wildfires that adversely impact ecosystems, natural resources, and human development. A primary consequence of these events is the impact on water quality and quantity. Of equal concern is evaluating how diverse land use configurations within a watershed can alter the physio-chemical properties of headwater reaches where drought and wildfire conditions are prevalent. To better understand the extent to which wildfires impact water quality and quantity across a headwater watershed, this study investigates wildfire impacts from the 2021 South Fire to Lytle Creek, a headwater stream of the Santa Ana …

Waste To Value: Global Perspective On The Impact Of Entomocomposting On Environmental Health, Greenhouse Gas Mitigation And Soil Bioremediation, Dennis Beesigamukama, Chrysantus M. Tanga, Subramanian Sevgan, Sunday Ekesi, Segenet Kelemu

All Peer-Reviewed Publications

The innovative use of insects to recycle low-value organic waste into value-added products such as food, feed and other products with a low ecological footprint has attracted rapid attention globally. The insect frass (a combination unconsumed substrate, faeces, and exuviae) contains substantial amounts of nutrients and beneficial microbes that could utilised as fertilizer. We analyse research trends and report on the production, nutrient quality, maturity and hygiene status of insect-composted organic fertilizer (ICOF) generated from different organic wastes, and their influence on soil fertility, pest and pathogen suppression, and crop productivity. Lastly, we discuss the impact of entomocomposting on greenhouse …

Phosphorus Dynamics In Calcareous Soils Amended With Organic Matter, Logan Banner

All Graduate Reports and Creative Projects, Fall 2023 to Present

Phosphorus (P) is considered immobile in calcareous soils. Organic matter is known to enhance P mobility in these soils. Few studies have considered what role iron oxides might play in P sorption in calcareous soils, especially in the presence of soluble organic matter. This study investigated P sorption dynamics in sand-based, simulated soil systems in the absence or presence of 5 mM carbon (C) as humic acid (HA). Treatments included combinations of dicalcium phosphate dihydrate (DCPD), calcite, and ferrihydrite. Solutions containing 10 mg P L^-1 in a background of 0.01 M CaCl₂were equilibrated with each solid treatment …

Constraining Silicate Weathering During The Middle Eocene Climatic Optimum (Meco) Using Radiolarian Ge/Si, Olivia R. Laub

All Graduate Theses and Dissertations, Fall 2023 to Present

Silicate weathering has long been considered a fundamental component of the earth system and has been cited as one of, if not the primary stabilizing feedback for climate. However, recent work has shown that the role of silicate weathering in the climate system is more complicated and dynamic than previously assumed. In this study I examine the role of weathering in the enigmatic warming event, the Middle Eocene Climatic Optimum (MECO) that occurred approximately 40 Ma. This event works as a good case study as there are multiple features of the MECO that differentiate it from other warming events that …

Multi-Objective Water Management In Idaho's Henrys Fork Watershed: Leveraging Reservoir Operation And Groundwater Pathways To Benefit Aquatic Habitat, Christina N. Morrisett

All Graduate Theses and Dissertations, Fall 2023 to Present

Multi-user water management is a challenging arena further complicated by climate change. This research is based in the Henrys Fork, Snake River, Idaho—an agricultural watershed that exemplifies those throughout the semi-arid American West. This dissertation uses an integrated approach that considers groundwater-river relationships, farm-scale decisions and basin-scale outcomes, upstream reservoir operation for downstream aquatic habitat, water rights, and collaborative stakeholder management to identify drought adaptation strategies accordingly.

Chapter 2 uses an interdisciplinary approach to quantify how improvements to irrigation efficiency at the farm-scale (i.e., converting from flood to sprinkler irrigation) can add up to affect hydrology at the landscape-scale and …

Controls On Sediment Connectivity In Fluvial Networks Impacted By Wildfire Across Utah, Alec Arditti

All Graduate Theses and Dissertations, Fall 2023 to Present

Flooding and sedimentation caused by wildfire are among the greatest threats to watersheds, fish populations and reservoirs in the western US. Burned landscapes are at risk for increased runoff and erosion and have the potential to transport sediment that may put downstream resources at risk. The ability of the channel to transport sediment downstream, known as the connectivity, is important for determining where impacts may occur. Sediment bottlenecks are locations within the watershed where local conditions produce a persistent decrease in downstream connectivity of sediment, resulting in increased sediment deposition and potentially a substantial modification of the local channel and …

Tropical Atlantic Temperature And Hydrologic Shifts During The Paleocene-Eocene Thermal Maximum, Chels Howard

All Graduate Theses and Dissertations, Fall 2023 to Present

The Paleocene-Eocene Thermal Maximum (PETM) is a geologic climate event that is studied heavily due to the similarities to anthropogenic climate change. This event occurred approximately 56 million years ago (Ma) and is characterized by a rapid release of carbon into the atmosphere, which resulted in an increase in temperature and a change in global climate events such as changes in patterns of evaporation and precipitation. We see this effect occurring in modern anthropogenic climate change due to the burning of fossil fuels releasing carbon dioxide (CO₂) into the atmosphere. In this study I use elemental data of …

Reducing Inputs And Adding Value To Turfgrass Systems Through Clover Inclusion And Plant Growth-Promoting Rhizobacteria Applications, Paige E. Boyle

All Graduate Theses and Dissertations, Fall 2023 to Present

Recently, the US has seen an expansion in the amount of turfgrass land cover (lawns, parks, roadsides, sports fields, and golf courses), as well as an interest in reducing fertilizer, water, and pesticide use in these grass systems. To help maintain quality and function while reducing resource inputs, two promising approaches have emerged: planting clover into lawns and applying plant growth-promoting rhizobacteria.

White clover and grass mixtures have been studied for their ability to cut down on fertilizer usage and provide a uniform, dark green lawn, but other clover types have not been as widely studied and may provide similar …

Ecology And Management Of Dyer's Woad (Isatis Tinctoria) In Northern Utah, Erin Marie Hettinger

All Graduate Theses and Dissertations, Fall 2023 to Present

Dyer’s woad (Isatis tinctoria L.) is a non-native forb that continues to threaten natural areas throughout Northern Utah and much of the Intermountain West. Once introduced, dyer’s woad can become extremely invasive, decreasing forage quality, and displacing native species. While dyer’s woad is found throughout much of Northern Utah, its range in other states remains limited. If promptly managed, control success in these areas will be much higher and populations may be kept at bay before ecological damage becomes severe.

This project tested the ability of dyer’s woad seedlings to compete with common rangeland grasslands at varied densities as …

Investigating Seismicity And Structure Of The Pecos, Texas Region Of The Delaware Basin Using A Temporary Nodal Network, Jenna Lynn Faith

Open Access Theses & Dissertations

With increasing earthquakes in the Delaware Basin since 2009, earthquake studies, including accurate hypocenters, are critically needed in the Delaware Basin to identify the structures producing earthquakes, and to determine if they are related to unconventional petroleum development and production. In 2018, with funding from the Texas Seismological Network (TexNet), the University of Texas at El Paso deployed and maintained a nodal network of 25 Magseis Fairfield Z-Land Generation 2 5-Hz seismic nodes in the Pecos, Texas region of the Delaware Basin, known as The Pecos Array. The network was deployed from November 2018 until the beginning of January 2020, …

Southern Rio Grande Rift Kinematics And Geochronology, Big Bend Fold Geometry, And The Use Of Real Data In Geoscience Education: Contributions To The Understanding Of Big Bend Geology And To Public Geoscientific Literacy, Jessica Kelsch

Open Access Theses & Dissertations

The Big Bend region of Trans-Pecos Texas preserves a rich record of Rio Grande rifting and Laramide-age contraction that provide intrigue to national and state park visitors and field trips for undergraduate geology students. Despite its well-exposed geologic record, the Big Bend region remains an underutilized natural laboratory for studying these two tectonic events. This dissertation combines structural studies of Rio Grande rift and Laramide structures with public outreach and geoscience education studies focused on the Big Bend region. In Chapter 2, existing extensional-kinematic studies from parts of this region are compiled with new fault kinematic and U-Pb geochronologic data …

Enhancing Our Understanding Of Ancient Oceans Through The Investigation Of Molybdenum Behavior Under Sulfidic Conditions, Rachel Faye Phillips

Open Access Theses & Dissertations

The most abundant trace metal in the ocean today, molybdenum (Mo), exhibits distinct behavior in oxygenated water, where it remains predominantly dissolved, compared to euxinic (i.e., oxygen-free and sulfidic) water, in which it is sequestered into the sediment. This dissimilar behavior allows us to use Mo concentrations and isotopic compositions in sediment to reconstruct marine oxygenation conditions throughout geologic history. However, Mo sequestration mechanisms under euxinic conditions remain unresolved, which limits the accuracy and precision of reconstructions made using Mo signatures in the rock record. For my doctoral research, I experimentally investigated abiotic and biotic Mo sequestration mechanisms under various …

Using Shallow Electromagnetic And Magnetic Techniques To Map Soil Texture And Characterize Salinity And Water Dynamics Below Pecan Orchards, El Paso County, Texas, Kristina Sasser

Open Access Theses & Dissertations

Non-invasive, near surface geophysical tools provide a time efficient and cost-effective approach to study the shallow subsurface. Electromagnetic induction (EMI) instruments are a category of these near surface methods that provide spatial and temporal information (2-D to 4-D) about shallow (<6 m) subsurface properties, from which soil salinity, clay content, and water content can be estimated. However, deconstructing soil apparent electrical conductivity (ECa) from EMI methods into its component parts remains a challenge. This research uses EMI and magnetic geophysical techniques to: (1) compare and contrast the distribution and behavior of ECa, both spatially and temporally, at two flood irrigated agricultural sites (pecan orchards) with different soil layers, properties, and controls on electrical conductivities that lie within the same floodplain in far west Texas; and (2) develop a one-dimensional inversion model using ECa and soil texture data at specified layers from established sites of known high and low ECa to determine soil layer resistivities at various dates during the irrigation season. Data are compared to soil sensor bulk EC and volumetric water content data at corresponding depths to validate results. Soils at both sites exhibit large ECa contributions from textural controls, and irrigation frequency. The combination of these two controls dictate where and how quickly secondary minerals precipitate, clog soil pores, reduce infiltration, and salinize the groundwater. Insight from this research aids in ongoing efforts to characterize vadose zone hydrology in dryland critical zones with high infiltration and serves as a guide for locations where future soil sampling will occur.

Alteration And Mineralization Of The Deep Extension Of The Giant Chuquicamata Porphyry Copper Deposit, Northern Chile, Claudio Andres Araya Torres

Open Access Theses & Dissertations

Porphyry copper deposits are the major source of copper and molybdenum in the world. The deposits consist of large volumes of rock altered by hydrothermal fluids released by shallow, intermediate composition magma chambers, with metallic mineralization present in veins, breccias, and disseminations; ore grades are typically 0.3-1.0 wt.% Cu. The subject of this study, the Chuquicamata porphyry copper deposit in northern Chile, is one of the most productive such deposits in the world, with over 45 million tons of Cu produced since large scale, open pit mining started early in the XXth century. Current production at Chuquicamata is from an …

Preliminary Assessment For Critical Minerals In The Terlingua Quicksilver District, Texas And Tres Marias Mine, Chihuahua, Mexico, Eduardo Lee Zuniga

Open Access Theses & Dissertations

The Terlingua Quicksilver district was discovered around the 1880s and was a mercury producing district from 1900 through 1946. The most productive years were during World War one and two. From 1900-1946 the Terlingua Quicksilver District (TQD) produced 150,000 flasks; 80% came from three mines: the Rainbow-Chisos, Mariposa, and Study Butte mines. The structural controls of the Mercury mineralization within these mines are breccia pipes and fractures, often located near igneous intrusions. This study will assess the potential for Critical Minerals and Rare Earth Elements in the Terlingua Quicksilver District. Fifty-five samples have been collected and analyzed for forty-four different …

Shallow Groundwater Distributions And Changes With Sea Level Rise In Seattle, Washington, Taylor L. Watson

Graduate Theses and Dissertations

Sea level rise (SLR) associated hazards, such as coastal flooding and erosion, are pressing issues of great concern for coastal communities across the globe. Shallow and emergent groundwater can contribute to groundwater hazards such as flooding, landslides, or damage to shallow infrastructure. This study investigates the shallow groundwater within Seattle, Washington, and projects how it will respond to SLR using interpolation and numerical groundwater modeling methods. Then, a geologic modeling method is presented as a preliminary investigation of heterogeneity and anisotropy within the aquifer system. In the results for the present-day interpolation, ~6 % of the coastal buffer –the total …

Modeling The Peak Ground Acceleration And Assessing The Economic Loss And Casualty Due To Potential Earthquakes Of Various Magnitudes In The New Madrid Seismic Zone, Mahmud Afroz

Graduate Theses and Dissertations

The New Madrid Seismic Zone (NMSZ) is one of the active tectonic zones capable of producing big earthquakes in the southcentral USA. The objective of this study was to assess the economic losses and casualties that might be caused by various magnitudes of seismic events in the NMSZ. The manifestation is the estimation for each magnitude which is using the Peak Ground Acceleration (PGA) that might occur during an earthquake. It is calculated using an attenuation function that correlates the intensity of local ground movement, the earthquake magnitude, and the distance from its epicenter. The assessment of casualties was conducted …

The Spatial And Temporal Distribution Of Large Rock Blocks And Control On Landscape Evolution In The Ozarks, Chelsea Moran

Graduate Theses and Dissertations

Geologists often use landscape form to infer landscape processes through time. While climate and tectonics shape geomorphic form, the potential range of spatial or temporal scales that can shape any specific landscape can render landscape process-form based hypotheses too general for consideration. Contributions by mathematical modeling have helped bridge the gap between inferring processes from form, notably in how sediment transport dynamics shape hillslopes. However, few models encapsulate the movement of large rock blocks ( >2 meters across) and their potential impact as hillslope sediment transport disruptors. The Upper Buffalo River watershed (BRW) in the Ozarks of northern Arkansas has …

Geospatial Analysis Of Weathering And Recession On Architectural Limestone At The 1891 Powerhouse/Icehouse In Eureka Springs, Arkansas, Stuart Bruce Wright

Graduate Theses and Dissertations

The objective of this study of the architectural limestone of the 1891 Powerhouse/Icehouse in Eureka Springs, Arkansas was to analyze the environmental factors that influenced the deterioration and surface recession of this historical stone structure. The focus of this research was to examine and establish a baseline study that may assist in future monitoring and documentation of this historic limestone structure on stone weathering. A replicable methodology was specifically created toward this baseline research in hopes that it represented a solid baseline study. Observations and data analyses revealed the relationship between the architectural limestone building structure and the dominating recession …

Tree-Ring Reconstruction Of Ouachita River Streamflow, Keaton Cade Jenkins-Joyce

Graduate Theses and Dissertations

The Ouachita River drains the Ouachita Mountains and Upper Coastal Plain in Arkansas and Louisiana. The Ouachita River is used for navigation, power generation, recreation, water supply, and wastewater treatment. The river has been prone to low flows during drought and extreme flooding, which were principal justifications for the construction of three large multipurpose dams on the stream. It is likely that the use of the Ouachita River will be stressed by future population growth, economic expansion, and climate change. For this study, tree-ring chronologies from various locations in and near the Ouachita River drainage basin were used to reconstruct …

Early Carbonate Diagenesis Of The Miocene Dam Formation In Southwestern Qatar, Mohammed Al-Musawi

Dissertations

The timing and mechanisms of platform-scale dolomitization have been the subject of a long and contentious scientific debate known as the “dolomite problem.” The current study provides new insights through an investigation of the Miocene mixed carbonate-siliciclastics-evaporites Dam Fm in southwestern Qatar. Petrographical, mineralogical, and geochemical data are integrated from two research cores, the Dam-01 and Dam-02. The Dam Fm provides an ideal site to investigate dolomitization because these rocks are: (i) relatively young, (ii) have not been deeply buried, (iii) exhibit no evidence of diagenetic resetting, and (iv) characterized by alternating meter-scale depositional cycles that help constrain the relative …

Globally-Distributed Microbial Eukaryotes Exhibit Endemism At Deep-Sea Hydrothermal Vents, Sarah K. Hu, Amy R. Smith, Rika E. Anderson, Sean P. Sylva, Michael Setzer, Maria Steadmon, Kiana L. Frank, Eric W. Chan, Darlene S. S. Lim, John A. Breier

School of Earth, Environmental, & Marine Sciences Faculty Publications

Single-celled microbial eukaryotes inhabit deep-sea hydrothermal vent environments and play critical ecological roles in the vent-associated microbial food web. 18S rRNA amplicon sequencing of diffuse venting fluids from four geographically- and geochemically-distinct hydrothermal vent fields was applied to investigate community diversity patterns among protistan assemblages. The four vent fields include Axial Seamount at the Juan de Fuca Ridge, Sea Cliff and Apollo at the Gorda Ridge, all in the NE Pacific Ocean, and Piccard and Von Damm at the Mid-Cayman Rise in the Caribbean Sea. We describe species diversity patterns with respect to hydrothermal vent field and sample type, identify …

Electrofacies Analysis Using A Geostatistical Approach, Northern Iraq Case Study, Hussein S. Hussein

Polytechnic Journal

The distribution of petrophysical parameters is governed by lithology, hence understanding the spatial variation in lithology is essential for reservoir characterisation. This study points out the use of well logs to estimate the lithology of carbonate rocks (limestone, marly limestone, dolomite, and dolomitic limestone) found in Upper Cretaceous to Miocene formations at the Khabbaz Oil Field in Northern Iraq. Applying the multivariate regression technique to neutron, and density data enabled accurate lithology prediction. By using independent values (well log data) to predict a dependent value (lithology), this technique is a progression of regression analysis. The formations under study comprised a …

Determining The P-Wave Velocity Structure In The Near-Surface Of Nw Miami, Florida, Using Quarry Blasts, Elham Moslemi

USF Tampa Graduate Theses and Dissertations

The fact that Florida is an earthquake-free region has caused seismologists to pay less attention to it. Few earthquakes in this state mean it is not a usual practice to study the propagation of seismic waves. However, utilizing data from quarry blasts, we studied wave propagation in this region. The primary objective of the project is to investigate the near-surface P-wave velocity structure and factors that may affect it. We also analyzed the amplitude of signals versus distance and blast size. A network of up to 10 Raspberry Shake instruments around the NW Miami-Lakes mining area was deployed where four …

Quantifying The Role Of Water Quality On Nitrogen Cycling In A Trophic Estuary, Kayla Gonzalez-Boy

Symposium of Student Scholars

Jobos Bay Estuary is an intertidal, tropical estuary located in southern Puerto Rico. The estuary covers about 12 km² and has a variety of habitats, such as seagrass beds, mangroves, mud flats, and coral reefs, which play important roles in sediment trapping and water quality maintenance. Seagrasses also serve as nursery and feeding grounds and provide shelter for macrofauna. Currently, the role of seagrasses and water quality on nitrogen (N) cycling in trophic estuaries is not well constrained. Understanding variations in sediment-based effects on N cycling rates and transformations, and how they are associated with water quality, is an …

The Geo/Thermochronology Of Dismal Island (Marguerite Bay, Antarctic Peninsula), Fati̇h Karaoğlan, Burcu Karataş, Yavuz Özdemi̇r, Erhan Gülyüz, Oleg Vassilev, Mahmut Oğuz Selbesoğlu, Semi̇h Gi̇ldi̇r

Turkish Journal of Earth Sciences

Dismal Island is located at the entrance of Marguerite Bay between Adelaide Island to the northeast and Alexander Island to the southwest within the Antarctic Peninsula (AP). Its unique position between Alexander and Adelaide islands provides the opportunity to perform testing and link these regions through Cenozoic magmatism and tectonics due to the subduction of the Pacific plate beneath the AP along the northern margin. Dismal Island was visited in February 2021 within the framework of the sixth Turkish Antarctic Expedition (TAE-VI). Thirteen samples were collected for petrography, geochronology, and low-temperature thermochronology (LTT). Of the samples, 3 were dated using …

Applicability Of Real-Time Ppp Technique In Polar Regions As An Accurate And Efficient Real-Time Positioning System, Reha Meti̇n Alkan, Serdar Erol, Bi̇lal Mutlu

Turkish Journal of Earth Sciences

The polar regions, which include the Arctic and Antarctic areas, attract the attention of people every day, and issues that are closely related to the future of humanity make these regions even more important. Accurate and reliable positioning in polar regions is very critical for scientific research projects and also for commercial, touristic, and other human activities. In this study, the usability and the accuracy performance of the real-time precise point positioning (RT-PPP) technique in high-latitude polar regions with harsh environmental and extreme atmospheric conditions were investigated. Within that framework, the GNSS dataset of six IGS multi-GNSS stations located at …

Webgis-Based Data Center Design For Polar Science Studies: Simulation Of Türkiye, Müge Şenel, Hasan Hakan Yavaşoğlu, Burcu Özsoy, Hi̇mmet Karaman, Mustafa Ümi̇t Gümüşay

Turkish Journal of Earth Sciences

Scientific studies concentrated in Antarctica hold great value and importance for humanity. Research projects are conducted in various disciplines on the continent, where nearly 100 research stations from 30 countries are established. Despite the challenges posed by Antarctica's natural structure, unique environment, difficult working conditions, and limited logistics opportunities, scientific research conducted there is indispensable due to the valuable information it offers. In pursuit of accessing this information, Turkish Antarctic expeditions have been organized since 2017. In this study, a polar data center was established through a web-based geographic information system (WebGIS), a significant infrastructure for the continuity of scientific …

Accuracy Assessment Of Glacier Depth Monitoring Based On Uav-Gpr On Horseshoe Island, Antarctica, Mahmut Oğuz Selbesoğlu, Mustafa Fahri̇ Karabulut, Özgün Oktar, Burak Akpinar, Oleg Vassilev, Mehmet Arkali, Şeyma Nur Tufan, Alptuğ Şeref Ayyildiz, Esra Günaydin, Ati̇lla Yilmaz, Doğaç Baybars Işiler, Burcu Özsoy

Turkish Journal of Earth Sciences

Unmanned aerial systems have a wide range of uses in studying the impacts of climate change over several fields. Recently, its combination with a ground-penetrating radar (GPR) technology has been demonstrated to be highly effective for surveying glaciers, especially in difficult and inaccessible terrains like Antarctica. In this context, this study focused on exploring the potential of using an unmanned aerial vehicle (UAV)-GPR to measure the depth of glaciers on Horseshoe Island, West Antarctica. The data were collected during the seventh Turkish Antarctic Expedition (TAE-VII) in February and March 2023, within the scope of the international project titled "Glacier monitoring …

Water Chemistry And Pigment Composition Of 13 Lakes And Ponds In Maritime Antarctica, Korhan Özkan

Turkish Journal of Earth Sciences

The Antarctic Peninsula has been rapidly warming, resulting in changes to the abundance and surface cover of terrestrial aquatic ecosystems, as well as their ecosystem structure and function. Therefore, comparative studies of aquatic ecosystems across large latitudinal gradients can be useful in better understanding these changes and making more reliable predictions regarding the consequences of climate change. During Turkish Antarctic Expeditions in 2018 and 2019, samples were collected from 10 lakes and 3 ponds across Maritime Antarctica (north-western coasts of the Antarctic Peninsula). These lakes and ponds were located on Ardley, Robert, Livingstone, Galindez, and Horseshoe islands, covering a latitudinal …