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Controls On Longitudinal Stream Profile Evolution In Guadalupe Mountains National Park, Samuel Schoenmann, Lisa Tranel, Eric W. Peterson, Jonathan Boyd Thayn Jan 2025

Controls On Longitudinal Stream Profile Evolution In Guadalupe Mountains National Park, Samuel Schoenmann, Lisa Tranel, Eric W. Peterson, Jonathan Boyd Thayn

Faculty Publications - Geography, Geology, and the Environment

Canyons in Guadalupe Mountains National Park are excellent locations to study the discrete boundary conditions that influence longitudinal channel profile evolution including climate, tectonics, hydrology, and lithology. The Guadalupe Mountain landscape records deep earth mantle processes in combination with surficial channel erosion and incision. Knickpoints and convex segments in longitudinal river profiles document impacts of climate change, tectonics, or surface processes. This study combines field observations with an analysis of longitudinal profile slopes and residual errors to evaluate how bedrock strength can be distinguished from features created by climate change, faulting, or subsidence in Pine Springs and McKittrick Canyons within …


Quantifying So₂ Emissions From Explosive Events Of The 2021 La Soufrière Eruption Using Dscovr/Epic, Yuxi Jin Jan 2025

Quantifying So₂ Emissions From Explosive Events Of The 2021 La Soufrière Eruption Using Dscovr/Epic, Yuxi Jin

Dissertations, Master's Theses and Master's Reports

Volcanic eruptions release large quantities of gases, including sulfur dioxide (SO₂), aerosol precursors, and ash into the atmosphere. Quantifying the emission fluxes and temporal variability of SO₂ is crucial for understanding volcanic processes and assessing their impacts on air quality, climate, and aviation safety. Episodic vulcanian to sub-Plinian explosive eruptions are a common feature of many arc volcanoes, but the underlying causes of such episodic behavior remain poorly understood. The 2021 La Soufrière eruption (St. Vincent) featured up to 40 discrete eruptive events between April 9 and April 22, presenting a rare opportunity to analyze time-resolved volcanic SO₂ emissions during …


Comprehensive Analysis Of Krauklis Waves And Long Period Seismic Events In Fluid-Filled Fractures Via Integrated Physical And Numerical Modeling, Sananda Ray Jan 2025

Comprehensive Analysis Of Krauklis Waves And Long Period Seismic Events In Fluid-Filled Fractures Via Integrated Physical And Numerical Modeling, Sananda Ray

Dissertations, Master's Theses and Master's Reports

Long-period (LP) seismic events, commonly recorded in volcanic and hydrothermal environments, are widely attributed to the resonance of fluid-filled fractures and the excitation of Krauklis waves along the solid-fluid interface. These low-velocity, dispersive waves are sensitive to both fluid dynamics and fracture geometry, offering critical insights into subsurface fluid transport, fracture evolution, and seismic source processes. Despite robust theoretical treatments, experimental validation under realistic geological conditions has remained limited. To address this, I aimed to develop a series of laboratory-based experimental models that systematically investigate the key physical mechanisms driving LP signal generation. In the first set of experiments, I …


Cover Crops Can Reduce Greenhouse Gas Emissions From No-Till Maize In Southern Brazil: Insights From A Long-Term Field Experiment, Guilherme Rosa Da Silva, Adam J. Liska, Cimélio Bayer Jan 2025

Cover Crops Can Reduce Greenhouse Gas Emissions From No-Till Maize In Southern Brazil: Insights From A Long-Term Field Experiment, Guilherme Rosa Da Silva, Adam J. Liska, Cimélio Bayer

Adam Liska Papers

Brazil is one of the countries that has the most agricultural area under no-till (NT) management. This research study aims to evaluate life-cycle greenhouse gas (GHG) emissions from maize (M) grain production in agroecosystems that used different cover crops under NT management in southern Brazil. The data for this study were from a long-term 41-year field experiment in southern Brazil. The long-term experiment evaluated the effects of fallow (F) and cover crops (oat (O), vetch (V), cowpea (B), pigeon pea (P), and lablab (L)) on nitrous oxide and methane emissions and soil carbon (C) sequestration in maize agroecosystems. Five cropping …


Fault Box Modeling Of Dip Slip Faults: A Framework For Fault Box Design And Future Studies, Hailey Pressnell Jan 2025

Fault Box Modeling Of Dip Slip Faults: A Framework For Fault Box Design And Future Studies, Hailey Pressnell

Master's Theses

The behavior of soils during surface fault rupture is a serious concern in the planning and design of infrastructure that may be located within or near a fault zone. Challenges associated with developing mitigation measures for surface fault rupture include the uncertainty of fault rupture and the variability of fault behavior. Current analytical procedures define surface fault rupture according to the type of fault movement (strike slip, normal or reverse), the amount of displacement on the fault, and the mechanics of the material overlying the fault. The purpose of this thesis is to reconfirm analytical solutions and gain a better …


Giving Props To Soil Property Predictive Models: Utilizing Mir To Predict Soil Health Properties, Diala M. Abboud Jan 2025

Giving Props To Soil Property Predictive Models: Utilizing Mir To Predict Soil Health Properties, Diala M. Abboud

Theses and Dissertations--Plant and Soil Sciences

Soil health is critical to sustaining life on Earth, influencing plant growth, agricultural productivity, water quality, and overall ecosystem sustainability. In response to climate change and intensifying land use, the need to improve our understanding of soil health has become increasingly urgent. The application of mid-infrared (MIR) spectroscopy coupled with statistical modeling has emerged as a promising, cost-effective approach to predict soil health parameters, offering a quicker alternative to traditional wet chemistry analyses. MIR methods have been successfully applied to predict various soil health properties, such as bulk density (BD), cation exchange capacity (CEC), base saturation (BS), electrical conductivity (EC), …


Evidence For Crustal Brines And Deep Fluid Infiltration In An Oceanic Transform Fault, Christine Chesley, Katherine Enright Jan 2025

Evidence For Crustal Brines And Deep Fluid Infiltration In An Oceanic Transform Fault, Christine Chesley, Katherine Enright

All Student Scholarship

Although oceanic transform faults (OTFs) are ubiquitous plate boundaries, the geological processes occurring along these systems remain underexplored. The Gofar OTF of the East Pacific Rise has gained attention due to its predictable, yet enigmatic, earthquake cycle. Here, we present results from the first ever controlled-source electromagnetic survey of an OTF, which sampled Gofar. We find that the fault is characterized by a subvertical conductor, which extends into the lower crust and thus implies deep fluid penetration. We also image subhorizontal crustal conductors distributed asymmetrically about the fault. We interpret these subhorizontal anomalies as crustal brines, and we suggest that …


Integrating Satellite-Based Precipitation Analysis: A Case Study In Norfolk, Virginia, Imiya M. Chathuranika, Dalya Ismael Jan 2025

Integrating Satellite-Based Precipitation Analysis: A Case Study In Norfolk, Virginia, Imiya M. Chathuranika, Dalya Ismael

Engineering Technology Faculty Publications

In many developing cities, the scarcity of adequate observed precipitation stations, due to constraints such as limited space, urban growth, and maintenance challenges, compromises data reliability. This study explores the use of satellite-based precipitation products (SbPPs) as a solution to supplement missing data over the long term, thereby enabling more accurate environmental analysis and decision-making. Specifically, the effectiveness of SbPPs in Norfolk, Virginia, is assessed by comparing them with observed precipitation data from Norfolk International Airport (NIA) using common bias adjustment methods. The study applies three different methods to correct biases caused by sensor limitations and calibration discrepancies and then …


Using Preformed Particle Gels To Control Transport In Geothermal Reservoirs: Mathematical Modeling, Philip Winterfeld, Baojun Bai, Yu Shu Wu Jan 2025

Using Preformed Particle Gels To Control Transport In Geothermal Reservoirs: Mathematical Modeling, Philip Winterfeld, Baojun Bai, Yu Shu Wu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We are developing swellable Preformed Particle Gels (PPG), which can control preferential fluid and heat flow through fracture networks to increase the performance of EGS reservoirs. Part of this development is a mathematical model and numerical simulator to simulate PPG treatments by considering coupled thermal-hydraulic-mechanical effects, and gel swelling kinetics and plugging efficiency, from which an optimized gel treatment design and operation can be achieved. The starting point for our mathematical model is the TOUGH2-CSM formulation and code. The TOUGH2-CSM fluid and heat flow formulation is based on the TOUGH2 one for multiphase, multicomponent, and multi-porosity systems, with the latter …


Predictive Modeling For Optimal Gel Treatment Design In Brownfields Using Ensemble Machine Learning And Data Upsampling Via Generative Ai, Munqith Aldhaheri, Baojun Bai, Mingzhen Wei Jan 2025

Predictive Modeling For Optimal Gel Treatment Design In Brownfields Using Ensemble Machine Learning And Data Upsampling Via Generative Ai, Munqith Aldhaheri, Baojun Bai, Mingzhen Wei

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Efficiently designed gel treatments play a vital role in extending the lifespan of brownfields through rejuvenating oil production. Recently, a three-mode mathematical methodology named the VCR approach has been proposed for designing effective treatments. To optimize this approach, it is crucial to determine the appropriate design mode systematically rather than relying solely on the intuitive judgments of field operators. This study introduces an advanced methodology for predicting the optimal design type of gel treatments using 12 reservoir and production variables. The methodology integrates ensemble machine-learning (EML) models with historical data from 65 field projects across 11 countries (1985-2020). The Random …


Landslide At River's Edge: Alum Bluff, Apalachicola River, Florida, Joann Mossa, Yin-Hsuen Chen Jan 2025

Landslide At River's Edge: Alum Bluff, Apalachicola River, Florida, Joann Mossa, Yin-Hsuen Chen

Center for Geospatial Science, Education & Analytics Faculty Publications

When rivers impinge on the steep bluffs of valley walls, dynamic changes stem from a combination of fluvial and mass wasting processes. This study identifies the geomorphic changes, drivers, and timing of a landslide adjacent to the Apalachicola River at Alum Bluff, the tallest natural geological exposure in Florida at similar to 40 m, comprising horizontal sediments of mixed lithology. We used hydrographic surveys from 1960 and 2010, two sets of LiDAR from 2007 and 2018, historical aerial, drone, and ground photography, and satellite imagery to interpret changes at this bluff and river bottom. Evidence of slope failure includes a …


Horizontal Infiltration Of Water Through Porous Snow As A Gravity Current, Anthony Cheng Jan 2025

Horizontal Infiltration Of Water Through Porous Snow As A Gravity Current, Anthony Cheng

Dartmouth College Master’s Theses

On the surface of the Greenland ice sheet or around the margins of the Antarctic ice shelf, water infiltrates porous ice. It is important to understand this infiltration process since water populating the pore space of ice directly impacts the density, porosity, and wetness of ice. These properties influence the mechanics and tensile strength of ice, as greater amounts of infiltration result in faster or more widespread deformation events, which may lead to adverse climatic effects such as sea level rise and ocean current disruption. While studies have considered the thermodynamics and fluid mechanics of water vertically percolating through snow …


Empirical Vulnerability Function Development Based On The Damage Caused By The 2014 Chiang Rai Earthquake, Thailand, Patcharavadee Hong, Masashi Matsuoka Jan 2025

Empirical Vulnerability Function Development Based On The Damage Caused By The 2014 Chiang Rai Earthquake, Thailand, Patcharavadee Hong, Masashi Matsuoka

Institute for Innovation & Entrepreneurship Publications

Seismic hazards in Thailand are frequently overlooked in disaster management planning, leading to insufficient research and significant economic losses during earthquake events. The 2014 Chiang Rai earthquake exposed critical vulnerabilities in Thailand's building practices due to widespread non-compliance with building codes and limited preparedness. This exposure prompted the development of empirical vulnerability functions using loss data from 15,031 damaged residences. The study analyzed government compensation records, which were standardized using replacement cost metrics. Three distinct models were developed through probabilistic and possibilistic modeling approaches. Residual analysis demonstrated the superior performance of the possibilistic approach, with the Possibilistic-based Vulnerability Function achieving …


The Role Of Floodplain Complexity In Wood Turtle Habitat Use, Laura S. Deming Jan 2025

The Role Of Floodplain Complexity In Wood Turtle Habitat Use, Laura S. Deming

Antioch University Dissertations & Theses

Wood turtles occupy cold, low-gradient riverine habitat throughout the northeastern United State and southeastern Canada. Stream alterations, such as dams, channel straightening, and floodplain development have diminished the natural hydrologic and sedimentation regimes that result in complex channel and floodplain geomorphology. Studies throughout the species’ range have quantified many aspects of their habitat, but none have quantified components of geomorphology of wood turtle sites. The goal of this study was to explore the role of stream channel and floodplain geomorphology in wood turtle habitat use, with specific objectives to (1) quantify components of stream channel and floodplain geomorphic complexity, (2) …


Biochar For Soil Amendment: Applications, Benefits, And Environmental Impacts, Ujjwal Pokharel, Gururaj Neelgund, Ram L. Ray, Venkatesh Balan, Sandeep Kumar Jan 2025

Biochar For Soil Amendment: Applications, Benefits, And Environmental Impacts, Ujjwal Pokharel, Gururaj Neelgund, Ram L. Ray, Venkatesh Balan, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

The excessive use of chemical fertilizers results in environmental issues, including loss of soil fertility, eutrophication, increased soil acidity, alterations in soil characteristics, and disrupted plant–microbe symbiosis. Here, we synthesize recent studies available from up to 2025, focusing on engineered biochar and its application in addressing issues of soil nutrient imbalance, soil pollution from inorganic and organic pollutants, soil acidification, salinity, and greenhouse gas emissions from fields. Application of engineered biochar enhanced the removal of Cr (VI), Cd²+, Ni²+, Zn²+, Hg²+, and Eu³+ by 85%, 73%, 57.2%, 12.7%, 99.3%, and 99.2%, …


Tidal Flooding Contributes To Eutrophication: Constraining Nonpoint Source Inputs To An Urban Estuary Using A Data Driven Statistical Model, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, Sophie Clayton, Peter W. Bernhardt, Thomas R. Allen Jan 2025

Tidal Flooding Contributes To Eutrophication: Constraining Nonpoint Source Inputs To An Urban Estuary Using A Data Driven Statistical Model, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, Sophie Clayton, Peter W. Bernhardt, Thomas R. Allen

OES Faculty Publications

In coastal urban areas, tidal flooding brings water carrying nutrients and particles back from land to estuarine and coastal waters. A statistical model to predict nutrient loads during tidal flooding events can help estimate nutrient loading from previous and future flooding events and adapt nutrient reduction strategies. We measured concentrations of dissolved inorganic nitrogen and phosphorus in floodwater at seven sentinel sites during 15 tidal flooding events from January 2019 to September 2020. The study area was the Lafayette River watershed in Norfolk, VA, USA, which is prone to tidal flooding and is predicted to experience more frequent and intense …


Seasonality Of Submarine Groundwater Discharge Pathways In A Coastal Lagoon Revealed By Radium Isotopes: The Importance Of Porewater Exchange In Summer, Júlia Rodriguez-Puig, Valentí Rodellas, Marc Diego-Feliu, Andres Alcolea, Joaquín Jiménez-Martínez, Irene Alorda-Montiel, Aaron Alorda-Kleinglass, Francisco Pereira, Marisol Manzano, Javier Gilabert, Jordi Garcia-Orellana Jan 2025

Seasonality Of Submarine Groundwater Discharge Pathways In A Coastal Lagoon Revealed By Radium Isotopes: The Importance Of Porewater Exchange In Summer, Júlia Rodriguez-Puig, Valentí Rodellas, Marc Diego-Feliu, Andres Alcolea, Joaquín Jiménez-Martínez, Irene Alorda-Montiel, Aaron Alorda-Kleinglass, Francisco Pereira, Marisol Manzano, Javier Gilabert, Jordi Garcia-Orellana

OES Faculty Publications

Chemical fluxes supplied by Submarine Groundwater Discharge (SGD) can be relevant for coastal ecosystems, particularly lagoonal environments. An appropriate understanding of SGD requires constraining the magnitude and composition of its different pathways. However, the evaluation of SGD pathways is often limited to independent estimations, lacking a comprehensive understanding of the groundwater processes at play. In this study, we combined a Ra mass balance and hydrogeological modeling to simultaneously estimate different SGD pathways flowing into a coastal lagoon. We assessed water fluxes derived from fresh SGD, long-scale recirculation of seawater, and porewater exchange (PEX) into Mar Menor, a highly anthropized coastal …


Successful Eastern Oyster (Crassostrea Virginica) Recruitment On Intertidal Artificial Substrates In Virginia, Usa, Rochelle D. Seitz, Kathleen E. Knick, Emily Suchonic, Amanda Pysher Jan 2025

Successful Eastern Oyster (Crassostrea Virginica) Recruitment On Intertidal Artificial Substrates In Virginia, Usa, Rochelle D. Seitz, Kathleen E. Knick, Emily Suchonic, Amanda Pysher

OES Faculty Publications

Declines of eastern oyster (Crassostrea virginica) populations and scarcity of natural oyster shell necessitate quantifying the effectiveness of artificial oyster reef substrates over varying environmental conditions. Oyster castles are often used in intertidal areas with moderate wave energy; however, new concrete, natural-looking substrates, GROW Reef Tiles, are now available. Eastern oyster recruitment and size on oyster castles (OC) and GROW Reef Tiles (GT), with 27% higher surface area on OC, were assessed three times over 25 months in locations with varying salinity. Four sites in the Chesapeake Bay region were examined: Cherrystone Inlet, Mockhorn Bay, Elizabeth River, and …


Unveiling Hidden Mercury And Methylmercury Sources: The Role Of Submarine Groundwater Discharge In Coastal Lagoons, Céline Lavergne, Júlia Rodriguez-Puig, Clara Ruiz-González, Maria Montero-Curiel, Gemma Casas, Daniel Romano-Gude, Irene Alorda-Montiel, Júlia Dordal-Soriano, Aaron Alorda-Kleinglass, Marc Diego-Feliu, Javier Gilabert, Alex Campillo-De La Maza, Cristina Romera-Castillo, Natalia Torres-Rodriguez, Lars-Eric Heimbürger-Boavida, Jordi Garcia-Orellana, Valenti Rodellas, Andrea G. Bravo Jan 2025

Unveiling Hidden Mercury And Methylmercury Sources: The Role Of Submarine Groundwater Discharge In Coastal Lagoons, Céline Lavergne, Júlia Rodriguez-Puig, Clara Ruiz-González, Maria Montero-Curiel, Gemma Casas, Daniel Romano-Gude, Irene Alorda-Montiel, Júlia Dordal-Soriano, Aaron Alorda-Kleinglass, Marc Diego-Feliu, Javier Gilabert, Alex Campillo-De La Maza, Cristina Romera-Castillo, Natalia Torres-Rodriguez, Lars-Eric Heimbürger-Boavida, Jordi Garcia-Orellana, Valenti Rodellas, Andrea G. Bravo

OES Faculty Publications

Mercury loads from Submarine Groundwater Discharge (SGD) may represent an overlooked source of methylmercury (MeHg) to the ocean, affecting human and ecosystem health. The SGD process involves the flow of fresh, saline, or mixed groundwater from coastal aquifers into the oceans classified in different components. Existing studies rarely report the fluxes supplied by the different SGD components; therefore, the relevance of SGD as a source of mercury remains unclear. We aimed to quantify SGD-driven mercury/methylmercury fluxes to the coast, focusing on the largest coastal lagoon in the western Mediterranean. We measured total dissolved mercury and MeHg in surficial and porewaters …


Applications Of Uav In Landslide Research: A Review, Boneng Chen, Jeremy Maurer, Weibing Gong Jan 2025

Applications Of Uav In Landslide Research: A Review, Boneng Chen, Jeremy Maurer, Weibing Gong

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Uncrewed aerial vehicles (UAVs), commonly known as drones, have gained significant popularity in landslide research due to their operational flexibility, near real-time planning capabilities, cost-effectiveness, high-resolution data outputs, and enhanced safety. This review aims to provide an analysis of UAV-based landslide investigation methodologies and their applications. It begins with an examination of UAV platforms and UAV-equipped sensors employed in landslide research, evaluating their advantages and limitations to guide appropriate platform and sensor selection. The review then explores UAV applications across three primary landslide investigation domains: landslide mapping, landslide monitoring, and landslide hazard assessment, highlighting some representative achievements in each domain. …


Visual Understanding Of Rock Wettability Distribution To Contact Angle Regions And Oil Displacement Patterns In The Silty Sand Reservoir Via 2d Pore-Scale Modeling, H. Al-Ajaj, W. Al-Bazzaz, Ralph E. Flori, S. Alsayegh, H. Almubarak, D. S. Ibrahim, H. Al-Saedi Jan 2025

Visual Understanding Of Rock Wettability Distribution To Contact Angle Regions And Oil Displacement Patterns In The Silty Sand Reservoir Via 2d Pore-Scale Modeling, H. Al-Ajaj, W. Al-Bazzaz, Ralph E. Flori, S. Alsayegh, H. Almubarak, D. S. Ibrahim, H. Al-Saedi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This study, conducted using a silty sand reservoir rock extracted from a Kuwait-producing oilfield, provides crucial insights into fluid distribution patterns and mineralogy, as well as wettability contact angle preferences. The method used for visual identification not only captures rock physics but also suggests effective oil recovery displacement strategies. Visual identification is presented using 2D image technology and a Scanning Electron Microscope (SEM). Analytical data are presented from electron bombardments and backscattering reflections collected in the BSE detector. These analyses were used to characterize the various surface boundary morphology parameters of the silty sand mineral surfaces, including area, perimeter, mineral …


Investigation Of Dynamic Adsorption And Desorption Of Polymer Nanogel In Porous Media Through Microfluidics, Junchen Liu, Fuqiao Bai, Abdulaziz A. Almakimi, Mingzhen Wei, Xiaoming He, Ibnelwaleed A. Hussein, Baojun Bai Jan 2025

Investigation Of Dynamic Adsorption And Desorption Of Polymer Nanogel In Porous Media Through Microfluidics, Junchen Liu, Fuqiao Bai, Abdulaziz A. Almakimi, Mingzhen Wei, Xiaoming He, Ibnelwaleed A. Hussein, Baojun Bai

Mathematics and Statistics Faculty Research & Creative Works

Understanding the transport and retention of elastic nanogel and microgel particles in porous media has been a significant research subject for decades, essential to the application of enhanced oil recovery (EOR). However, a lack of dynamic adsorption and desorption studies, in which the kinetics in porous media are seldom investigated, hinders the design and application of polymer nanogel in underground porous media. In this work, we visualized and quantified the transport and dynamic adsorption of polymer nanogel in 3D glass micromodels that were manufactured by packing glass beads in capillaries. Calibrating the linearity of fluorescence intensity to concentration, we calculated …


Re-Crosslinkable Particle For Conformance Control And Temporary Plugging, Yifu Long, Bowen Yu, Baojun Bai, Thomas P. Schuman Jan 2025

Re-Crosslinkable Particle For Conformance Control And Temporary Plugging, Yifu Long, Bowen Yu, Baojun Bai, Thomas P. Schuman

Patents

The present invention generally relates to the composition of particle gels for conformance control, well drilling and well treatments. More particularly, this invention relates to swellable polymer particle gels that can re-crosslink, i.e., reassociate and self-heal, at subterranean conditions. These particle gels can be deployed to improve the conformance of water flooding of especially matrix bypass events (MBEs), that are also known as void space conduits. Moreover, these particle gels can be deployed for controlling the water production and increasing of petroleum recovery. The inventive particles can also be deployed as diverter for well stimulation.


Nontoxic High Temperature Resistant Hydrogels, Thomas P. Schuman, Baujun Bai, Buddhabhushan Pundlik Salunkhe Jan 2025

Nontoxic High Temperature Resistant Hydrogels, Thomas P. Schuman, Baujun Bai, Buddhabhushan Pundlik Salunkhe

Patents

Compositions of swellable non-toxic hydro gels and their use in conformance control are described herein. More specifically, the present invention generally relates to the hydro gels compositions that can be used to treat the oil reservoirs having high temperature and high salinity conditions. The compositions generally comprise a plurality of swellable particles having one or more crosslinkers interspersed within a polymer matrix. The compositions can also be used in biomedical, agricultural, fracking and similar applications wherein thermally-stable, nontoxic hydrogels are required.


Conservation And Survey Division 2024 Annual Report, R.M. Joeckel, Michele Waszgis Jan 2025

Conservation And Survey Division 2024 Annual Report, R.M. Joeckel, Michele Waszgis

Conservation and Survey Division: Faculty and Staff Publications

The Conservation and Survey Division of the University of Nebraska - Lincoln is the agency designated by statute to investigate and interpret the geologically related natural resources of the State, to make available to the public the results of these investigations, and to assist in the development and conservation of these resources. It consists of program areas in geology, water, soils and remote sensing-geographic information systems.


Old, Flat, And Slow: Interior Greenland Snow And Ice Dynamics Revealed With Gnss, Derek James Pickell Jan 2025

Old, Flat, And Slow: Interior Greenland Snow And Ice Dynamics Revealed With Gnss, Derek James Pickell

Dartmouth College Ph.D Dissertations

The interior dry snow zone region of the Greenland Ice Sheet can no longer be confidently considered a reliably melt-free region, yet our ability to investigate and quantify the dynamic nature of this landscape is hindered by its remoteness. To overcome this challenge, this work describes a novel, low-cost, low-power GNSS (positioning) instrument that enables simultaneous measurements of (1) ice accumulation/ablation changes and (2) 3D ice flow. Deployed in a dense array, these GNSS instruments achieve similar performance to scientific-grade, commercial options (cm- to mm- precision), yet operate at < 60% of the power and < 34% of the hardware cost. Over a three year campaign, we analyze spatial and temporal patterns of accumulation in this region, using a technique called GNSS interferometric reflectometry (GNSS-IR). Observations with this technique show low bias and high precision relative to a validation study (-2.1 ± 2.9 cm), while we also demonstrate for the first time how GNSS-IR can reveal cm- to m- scale surface roughness, a critical yet often neglected measurement due to longstanding observational challenges. Patterns of accumulation show a spatial dependence linked to surface slope (~+0.7 mm w.e. km^-1 westward away from the divide) while surface roughness has a temporal dependence likely driven by wintertime high winds. Next, we combine GNSS-IR surface heights with the geodetic position time series of the antenna to derive surface elevation changes, which are compared to coincident ICESat-2 laser altimetry elevations. Observations of the surface show a millimeter-level relative bias and cm-level precision (-0.9 ± 3.8 cm) compared with the satellite altimeter, demonstrating for the first time that this technique is a viable ground-truthing method, while ICESat-2 performance has continued to exceed mission performance requirements. Finally, we examine station positioning through time to show a sensitivity to dynamic ice thinning and firn densification, two parameters than cannot be finely observed with space-based methods in this region. Together, these results provide the first ground‑based, high‑resolution picture of interior ice‑sheet change—capturing accumulation, roughness, surface elevation, and strain in one unified dataset. Our approach dramatically lowers logistical barriers, opening the interior of Greenland (and other remote regions) to sustained, quantitative monitoring at unprecedented spatiotemporal resolution.


Spatial Analysis Of American Chestnut (Castanea Dentata) Distribution And Ecology In Kentucky’S Federal Lands, Jacob Raymond Pease Jan 2025

Spatial Analysis Of American Chestnut (Castanea Dentata) Distribution And Ecology In Kentucky’S Federal Lands, Jacob Raymond Pease

Murray State Theses and Dissertations

Anthropogenic factors have been the cause of the decline of tree species across the globe. From unsustainable logging and development to disease and improper management, threats to forests have taken their toll. The American chestnut (Castanea dentata) was once an integral basal tree species in Appalachian forests, but chestnut blight drove the species to functional extinction by the mid-1900s. The recent creation of genetically modified chestnuts gives hope for future restoration of the species throughout its historical range. Despite blight resistance, effective restoration will require optimal site selection for finding and planting chestnuts, which will maximize limited resources. …


Groundwater Pumping Impacts On Stream Depletion In Humboldt County, Ca: Integrating Analytical Models And Field Data, Andy Hans Heise Jan 2025

Groundwater Pumping Impacts On Stream Depletion In Humboldt County, Ca: Integrating Analytical Models And Field Data, Andy Hans Heise

Cal Poly Humboldt theses and projects

This study addresses the significant concern of stream depletion from groundwater pumping in Humboldt County, CA. The objective of this study is to develop an analytical model for estimating stream depletion and integrating field data into model parameters.

The methodology involved conducting a field study near three operating wells by a stream, installing stream gages upstream and downstream of the wells, and recording pumping rates and schedules for two of the wells. The third well’s pumping data was synthetically generated, for privacy concerns of the well owner. The StreamDepletR package was used for estimating depletion rates in a stream in …


Carbon Dynamics Across The Mangrove-Tidal Flat Ecotone In A Tropical Seascape, E. S. Yando, I. J.B. Alemu, L. Kiah Eng, T. M. Sloey, M. Van Breugel, Bhatia N. Friess Jan 2025

Carbon Dynamics Across The Mangrove-Tidal Flat Ecotone In A Tropical Seascape, E. S. Yando, I. J.B. Alemu, L. Kiah Eng, T. M. Sloey, M. Van Breugel, Bhatia N. Friess

Biological Sciences Faculty Publications

Mangroves and other blue carbon ecosystems are important for climate through the storage and sequestration of carbon. Most research estimates carbon dynamics by subsampling central portions of the ecosystem and are then upscales using habitat maps to patch, landscape, or regional levels. However, heterogeneity is rarely accounted for - particularly at edges. Further, adjacent tidal flat ecosystems have only recently been considered for carbon storage, but may be undervalued if areas where they transition with vegetated systems are not accounted for. To address the lack of information at coastal ecotones, we examined both soil carbon storage and carbon dioxide flux …


Exploring Nitrate Reduction In A Saturated Riparian Buffer Through A Three-Dimensional Reactive Contaminant Transport Model In An Agricultural Area, Mcclean County Central Illinois, Franklin O. Ijigade Jan 2025

Exploring Nitrate Reduction In A Saturated Riparian Buffer Through A Three-Dimensional Reactive Contaminant Transport Model In An Agricultural Area, Mcclean County Central Illinois, Franklin O. Ijigade

Theses and Dissertations

Saturated Riparian Buffers (SRBs) are engineered systems designed to remove nitrate and other pollutants from subsurface agricultural drainage water before it reaches a stream. This study utilizes a high-resolution coupled flow and reactive transport model to explore nitrate reduction and transformation in an SRB in glacial sediment. The influence of material heterogeneity on nitrate reduction and the effectiveness of the SRB was investigated. The study was conducted in an SRB located next to and receiving tile drainage water that ultimately drains into a 3rd order stream (T3 stream) in central Illinois, USA. A three-dimensional steady groundwater flow model was …