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Articles 2641 - 2669 of 2669
Full-Text Articles in Earth Sciences
Erratum: New Estimates Of The Magnitude Of The Sea-Level Jump During The 8.2 Ka Event, (Geology (2022), 50(1), (86–90), (10.1130/G49296.1)), Jonathan Obrist-Farner, Mark Brenner, Jeffery R. Stone, Marta Wojewódka-Przybył, Thorsten Bauersachs, Andreas Eckert, Marek Locmelis, Jason H. Curtis, Susan R.H. Zimmerman, Alex Correa-Metrio, Lorenz Schwark, Edward Duarte, Antje Schwalb, Etienne Niewerth, Paula Gabriela Echeverría-Galindo, Liseth Pérez
Erratum: New Estimates Of The Magnitude Of The Sea-Level Jump During The 8.2 Ka Event, (Geology (2022), 50(1), (86–90), (10.1130/G49296.1)), Jonathan Obrist-Farner, Mark Brenner, Jeffery R. Stone, Marta Wojewódka-Przybył, Thorsten Bauersachs, Andreas Eckert, Marek Locmelis, Jason H. Curtis, Susan R.H. Zimmerman, Alex Correa-Metrio, Lorenz Schwark, Edward Duarte, Antje Schwalb, Etienne Niewerth, Paula Gabriela Echeverría-Galindo, Liseth Pérez
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
No abstract provided.
Preface : Fruit And Vegetable Waste Utilization And Sustainability, Sachin A. Mandavgane, Ipsita Chakravarty, Amit Jaiswal
Preface : Fruit And Vegetable Waste Utilization And Sustainability, Sachin A. Mandavgane, Ipsita Chakravarty, Amit Jaiswal
Books/Book Chapters
Fruits and vegetables are an important source of nutrition and a key element of a healthy balanced diet. Several organizations such as the World Health Organization (WHO), Food and Agriculture Organization of United Nations (FAO), and Food Health England suggest consuming more than 400 g of fruits and vegetables per day (roughly five portions per day) to improve overall health and reduce the risk of certain cardiovascular diseases and cancer; subsequently, consumption and production of fruits and vegetables are on the rise. The increased consumption/production of fruits and vegetables has resulted in huge quantities of waste (approximately 42% of the …
Investigating Pore Body, Pore Throat, Nano-Pore Wettability Preference In Several Unconventional Kuwaiti Carbonate Reservoirs, Saleh Al-Sayegh, Ralph E. Flori, Hussain Alajaj, Waleed Hussien Al-Bazzaz
Investigating Pore Body, Pore Throat, Nano-Pore Wettability Preference In Several Unconventional Kuwaiti Carbonate Reservoirs, Saleh Al-Sayegh, Ralph E. Flori, Hussain Alajaj, Waleed Hussien Al-Bazzaz
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
This study will investigate measuring the wettability contact angles of native unconventional tight carbonate as well as other unconventional pore system reservoir samples that hosts varied pore shapes and subsequent wettability contact angle distributions in both reservoir matrix and possible natural fractures. Also, the investigation will include validation of the grain/ pore-wall wettability regions and classify the natural wettability preference available inside pores of the rock and their overall wettability performance and recovery efficiency contributions. Further investigation will include modeling pore throat contact angle wettability, and to understand their new physics that will advance reservoir characterization and oil recovery improvement.
Kuwaiti Carbonate Reservoir Oil Recovery Prediction Through Static Wettability Contact Angle Using Machine Learning Modeling, Saleh Al-Sayegh, Ralph E. Flori, Waleed Hussien Al-Bazzaz, Hasan Al-Saedi, Mostafa Al-Kaouri, Ali Qubian
Kuwaiti Carbonate Reservoir Oil Recovery Prediction Through Static Wettability Contact Angle Using Machine Learning Modeling, Saleh Al-Sayegh, Ralph E. Flori, Waleed Hussien Al-Bazzaz, Hasan Al-Saedi, Mostafa Al-Kaouri, Ali Qubian
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The objective of this study is to predict EOR efficiencies through static wettability contact angle measurement by Machine Learning (ML) modeling. Unlike conventional methods of measuring static wettability contact angle, the unconventional digital static wettability contact angle is captured and measured, then (ML) modeled in order to forecast the recovery based on wettability distribution phenomenon. Due to success in big data collection from reservoir imaging samples, this study applies data science lifecycle logic and utilizes Machine Learning (ML) models that can predict the recovery through wettability contact angles and thus identify the treatment of oil recovery for a candidate reservoir. …
Re-Assembling Polymer Particle Package For Conformance Control And Fluid Loss Control, Jingyang Pu, Baojun Bai, Thomas P. Schuman
Re-Assembling Polymer Particle Package For Conformance Control And Fluid Loss Control, Jingyang Pu, Baojun Bai, Thomas P. Schuman
Patents
This invention is broadly concerned with compositions and processes for oilfield applications. More specifically, this invention relates to novel polymer constructed packages that, when pumped into a petroleum well, provide tunable characteristics of transformation and delayed self-assembly with each other under reservoir conditions to yield strong, elastic, bulk gel materials. The compositions comprise a polymer, assembling agents, and optional additives used for the re-assembly stage are uniformly-distributed within the initial gel particles. The polymer particle packages absorb water and swell upon exposure to water, thus exposing the "assembling agents" that enable re-assembly. Both swelling and re-assembly are proportionally controlled via …
Cylindrical Mega-Voids In Quaternary Aeolianites, Little Exuma Island, The Bahamas: Georadar Response, Ilya Val Buynevich, H. Allen Curran, Bosiljka Glumac, Michael Savarese, Lisa Park Boush
Cylindrical Mega-Voids In Quaternary Aeolianites, Little Exuma Island, The Bahamas: Georadar Response, Ilya Val Buynevich, H. Allen Curran, Bosiljka Glumac, Michael Savarese, Lisa Park Boush
Geosciences: Faculty Publications
In addition to karst features, tropical carbonates contain a wide range of smaller cylindrical voids (“pipes”) attributed to bioturbation, tree molds, or dissolution, among others. During geophysical investigation of the Little Exuma Island, The Bahamas, several sites with enigmatic voids were investigated using a high-frequency ground-penetrating radar (GPR) imaging.
The aim of the paper is to assess the feasibility of GPR to detect voids within lithified Holocene calcarenites of the Hannah Bay Member
Plastic Storage In River Sediments Across An Urbanization Gradient In The Ipswich Watershed In Massachusetts, Jackie L. Harris
Plastic Storage In River Sediments Across An Urbanization Gradient In The Ipswich Watershed In Massachusetts, Jackie L. Harris
Honors Theses and Capstones
The importance of plastic pollution research has become apparent as plastic pollution has increased exponentially since its introduction in the 1950s. Plastics mechanically break down into minuscule particles called microplastics, which are plastic particles with a size range of 0.1 micrometers (μm) to 5 millimeters (mm). Most of the research on microplastic pollution has centered around marine ecosystems rather than freshwater ecosystems. More freshwater microplastic research to date is emerging but is still nascent and sparse. Furthermore, the idea that rivers are merely conduits of microplastics to the ocean is even more limited and ignores microplastic loading and retention in …
Electron Beam Treatment For The Removal Of 1,4-Dioxane In Water And Wastewater, Robert Pearce, Xi Li, John Vennekate, Gianluigi Ciovati, Charles Bott
Electron Beam Treatment For The Removal Of 1,4-Dioxane In Water And Wastewater, Robert Pearce, Xi Li, John Vennekate, Gianluigi Ciovati, Charles Bott
Electrical & Computer Engineering Faculty Publications
Electron beam (e-beam) treatment uses accelerated electrons to form oxidizing and reducing radicals when applied to water without the use of external chemicals. In this study, electron beam treatment was used to degrade 1,4-dioxane in several water matrices. Removal improved in the progressively cleaner water matrices and removals as high as 94% to 99% were observed at a dose of 2.3 kGy in secondary effluent. 1,4-dioxane removal was confirmed to be primarily through hydroxyl radical oxidation. The calculated electrical energy per order was found to be 0.53, 0.26, and 0.08 kWh/m3/order for secondary effluent (Avg. total organic carbon …
Integrating Remote And In-Situ Techniques To Quantify Landscape Evolution, Matthew Maclay
Integrating Remote And In-Situ Techniques To Quantify Landscape Evolution, Matthew Maclay
Dartmouth College Master’s Theses
With the increasing availability and resolution of remote sensing techniques, the resulting data products are increasingly being applied to answer societally relevant questions regarding quantifying the effects of climate change, mitigating natural hazards, and understanding landscape changes over varying temporal and spatial scales. While the power and potential for such large-scale, efficient, and cost-effective surveys are undeniable, a thorough understanding of any environment requires that remotely sensed data are ground-truthed or put into context with in-situ observations. In this thesis, Chapter 1 presents a literature review of Martian analog sites and discusses the importance of integrating in-situ and remote sensing …
Timing And Source Of Water Supporting Early Lakes In The Xanthe Terra Region Of Mars, Noemi A. Ortega Dominguez
Timing And Source Of Water Supporting Early Lakes In The Xanthe Terra Region Of Mars, Noemi A. Ortega Dominguez
Dartmouth College Master’s Theses
Whether an ancient ocean existed on Mars remains controversial. Modeling of Mars’ early climate indicates a dry and cold environment; meanwhile geologic evidence supports a wet and warm environment that potentially hosted a globally connected aquifer with a northern ocean. One geomorphic line of evidence in support of persistent standing water and a northern ocean are inferred deltaic deposits along and near the Mars dichotomy boundary. However, not all these deltaic deposits appear to have consistent delta front elevations, and many are within craters, calling into question whether these deposits formed within the same body of water or even at …
Active Learning For Efficient Soil Monitoring In Large Terrain With Heterogeneous Sensor Network, Hui Chen, Ju Wang
Active Learning For Efficient Soil Monitoring In Large Terrain With Heterogeneous Sensor Network, Hui Chen, Ju Wang
Publications and Research
Soils are a complex ecosystem that provides critical services, such as growing food, supplying antibiotics, filtering wastes, and maintaining biodiversity; hence monitoring soil health and domestication is required for sustainable human development. Low-cost and high-resolution soil monitoring systems are challenging to design and build. Compounded by the sheer size of the monitoring area of interest and the variety of biological, chemical, and physical parameters to monitor, naive approaches to adding or scheduling more sensors will suffer from cost and scalability problems. We investigate a multi-robot sensing system integrated with an active learning-based predictive modeling technique. Taking advantage of advances in …
Effects Of Lead Exposure On Birds Breeding In The Southeast Missouri Lead Mining District, Rebecka Brasso, Danielle Cleveland, Frank R. Thompson Iii, David E. Mosby, Kathy Hixson, Melissa Roach, Barnett A. Rattner, Natalie K. Karouna-Renier, Julia S. Lankton
Effects Of Lead Exposure On Birds Breeding In The Southeast Missouri Lead Mining District, Rebecka Brasso, Danielle Cleveland, Frank R. Thompson Iii, David E. Mosby, Kathy Hixson, Melissa Roach, Barnett A. Rattner, Natalie K. Karouna-Renier, Julia S. Lankton
United States Geological Survey: Staff Publications
Lead mining in the Southeast Missouri Lead Mining District began in the 1700s and continued for nearly 300 years; the waste piles associated with smelting, mining, and milling of lead ores have released metal residues that have contaminated soil and water in the region. Previous studies in the district have indicated potential harm to wildlife, including birds, because of elevated lead concentrations associated with mining. Exposure to soil-borne lead was correlated with elevated lead concentrations in tissues, inhibition of δ-aminolevulinic acid dehydratase (δALAD), and renal lesions in birds foraging on ground-dwelling invertebrates at contaminated sites (compared to reference sites) in …
A Method For Successful Collection Of Multicores And Gravity Cores From Antarctic Subglacial Lakes, Brad E. Rosenheim, Alexander B. Michaud, James Broda, Alan Gagnon, Ryan A. Venturelli, Timothy D. Campbell, Amy Leventer, Molly Patterson, Matthew J. Siegfried, Brent C. Christner, Dennis Duling, David M. Harwood, John E. Dore, Martyn Tranter, Mark L. Skidmore, John C. Priscu, Salsa Science Team
A Method For Successful Collection Of Multicores And Gravity Cores From Antarctic Subglacial Lakes, Brad E. Rosenheim, Alexander B. Michaud, James Broda, Alan Gagnon, Ryan A. Venturelli, Timothy D. Campbell, Amy Leventer, Molly Patterson, Matthew J. Siegfried, Brent C. Christner, Dennis Duling, David M. Harwood, John E. Dore, Martyn Tranter, Mark L. Skidmore, John C. Priscu, Salsa Science Team
Department of Earth and Atmospheric Sciences: Faculty Publications
During the 2018–2019 Antarctic field season, the Subglacial Antarctic Lakes Scientific Access project team cleanly accessed Mercer Subglacial Lake, West Antarctica, to sample water and sediments beneath 1087 m of overlying ice. A multicorer was successful in sampling the sediment–water interface, with 4 deployments retrieving 10 cores between 0.3 and 0.4 m in length. Gravity coring was also successful, retrieving cores of 0.97 and 1.78 m in glacial diamict. However, sediment cores retrieved by the gravity cores were shorter than the core barrel penetration (as measured by mud streaks on the outside of the coring system), indicating that the system …
Reply To The Discussion And Comments Of Azerêdo Et Al. (2023) And Schneider Et Al. (2023) On The Paper By Magalhães Et Al. ‘Middle Jurassic Multi-Scale Transgressive–Regressive Cycles: An Example From The Lusitanian Basin’, The Depositional Record, 9, 174–202, Antonio J.C. Magalhães, Gerson J.S. Terra, Felipe Guadagnin, Daniel G.C. Fragoso, Mirian C. Menegazzo, Nuno L.A. Pimentel, Sissa Kumaira, Gerson Fauth, Alessandra Santos, David K. Watkins, Mauro D.R. Bruno, Daiane Ceolin, Simone Baecker-Fauth, Guilherme P.R. Gabaglia, Washington L.E. Teixeira, Francisco P. Lima-Filho
Reply To The Discussion And Comments Of Azerêdo Et Al. (2023) And Schneider Et Al. (2023) On The Paper By Magalhães Et Al. ‘Middle Jurassic Multi-Scale Transgressive–Regressive Cycles: An Example From The Lusitanian Basin’, The Depositional Record, 9, 174–202, Antonio J.C. Magalhães, Gerson J.S. Terra, Felipe Guadagnin, Daniel G.C. Fragoso, Mirian C. Menegazzo, Nuno L.A. Pimentel, Sissa Kumaira, Gerson Fauth, Alessandra Santos, David K. Watkins, Mauro D.R. Bruno, Daiane Ceolin, Simone Baecker-Fauth, Guilherme P.R. Gabaglia, Washington L.E. Teixeira, Francisco P. Lima-Filho
Department of Earth and Atmospheric Sciences: Faculty Publications
cently published paper. The exchange of ideas, data and interpretation improves our knowledge and is the right way to discuss science's advances. This reply considers the points raised by Azerêdo et al. (2023) and Schneider et al. (2023). In both manuscripts, these authors raised many issues about sedimentological and stratigraphic aspects that can be separated into two groups: (a) those related to the age of the studied succession; and (b) those assigning the studied succession to the Candeeiros Formation.
Berriasian–Valanginian Geochronology And Carbon-Isotope Stratigraphy Of The Yellow Cat Member, Cedar Mountain Formation, Eastern Utah, Usa, Robert M. Joeckel, Celina A. Suarez, Noah M. Mclean, Andreas Möller, Gregory A. Ludvigson, Marina B. Suarez, James I. Kirkland, Joseph Andrew, Spencer Kiessling, Garrett A. Hatzell
Berriasian–Valanginian Geochronology And Carbon-Isotope Stratigraphy Of The Yellow Cat Member, Cedar Mountain Formation, Eastern Utah, Usa, Robert M. Joeckel, Celina A. Suarez, Noah M. Mclean, Andreas Möller, Gregory A. Ludvigson, Marina B. Suarez, James I. Kirkland, Joseph Andrew, Spencer Kiessling, Garrett A. Hatzell
Conservation and Survey Division: Faculty and Staff Publications
The Early Cretaceous Yellow Cat Member of the terrestrial Cedar Mountain Formation in Utah, USA. has been interpreted as a “time-rich” unit because of its dinosaur fossils, prominent paleosols, and the results of preliminary chemostratigraphic and geochronologic studies. Herein, we refine prior interpretations with: (1) a new composite C-isotope chemostratigraphic profile from the well-known Utahraptor Ridge dinosaur site, which exhibits δ13C features tentatively interpreted as the Valanginian double-peak carbon isotope excursion (the so-called “Weissert Event”) and some unnamed Berriasian features; and (2) a new cryptotephra zircon eruption age of 135.10 ± 0.30/0.31/0.34 Ma (2σ) derived from the CA-ID-TIMS …
Oh The Places Snow Blows: Observations And Impacts Of Snow Redistribution On Arctic Sea Ice, David Clemens-Sewall
Oh The Places Snow Blows: Observations And Impacts Of Snow Redistribution On Arctic Sea Ice, David Clemens-Sewall
Dartmouth College Ph.D Dissertations
Arctic sea ice has declined dramatically due to climate change. This decline impacts Arctic communities, ecosystems, international trade, and the world's climate. However, due to uncertain physical processes, climate models generally do not capture the severity of the observed decline---adding uncertainty to projections of future climate change. A major uncertainty in the Arctic sea ice component of climate models is how much heat passes through the snow on top of the ice in the winter. This heat flux controls how much ice grows each winter, impacting how much ice survives the summer melt. Snow is an excellent thermal insulator (about …
Rain-Induced Hazards In Remote, Low-Resource Communities: A Case Study Of Flash Flooding In The Usulután Department, El Salvador, Natalea Cohen
Rain-Induced Hazards In Remote, Low-Resource Communities: A Case Study Of Flash Flooding In The Usulután Department, El Salvador, Natalea Cohen
Dissertations, Master's Theses and Master's Reports
Rain-induced natural hazards can lead to devastating and potentially life-threatening impacts. Understanding areas susceptible to flash flooding and characterizing the intensity of flash flood events is critical in improving the mitigation and emergency preparedness of vulnerable communities. Flash floods occur on small spatial scales and for short durations making it challenging to classify flash flood susceptibility and forecast events. Modeling flash flooding becomes even more difficult when focusing on data-poor regions. This study is based in California, El Salvador, an agricultural community located in the Central American Dry Corridor (CADC), a region experiencing the impacts of climate change and associated …
Relationships Between Geochemistry, Carbon Content, And Grain Size In Clastic Cave Sediments, Rebekah Rose Nicholas
Relationships Between Geochemistry, Carbon Content, And Grain Size In Clastic Cave Sediments, Rebekah Rose Nicholas
Graduate Theses, Dissertations, and Problem Reports (ETD)
Understanding geochemical and physical properties of cave sediment gives insight to sediment characterization and carbon storage in the cave system. Previous work on clastic sediments largely encompasses physical properties, neglecting the importance of geochemical parameters on sediment deposition.
This study reports physical and chemical properties of sediment cores from three caves: two caves in Puerto Rico and one cave in Virginia. A total of 25 cores were used in this study; 6 of these cores were new and collected in 2022 from Butler Cave (BTC) in Virginia to focus on the effects of water level. Core samples were analyzed for …
Evaluating The Relative Influence Of Soil Water Potential, Soil Moisture, And Vapor Pressure Deficit On Semi-Arid Vegetation Dynamics, Kayla R. Jamerson
Evaluating The Relative Influence Of Soil Water Potential, Soil Moisture, And Vapor Pressure Deficit On Semi-Arid Vegetation Dynamics, Kayla R. Jamerson
Graduate Student Theses, Dissertations, & Professional Papers
Knowledge of vegetation’s response to soil water availability and atmospheric demand is critical to understanding the impact of climate change on semi-arid ecosystems. However, limited field-based research has been conducted to assess the relative importance of these drivers and previous research has simplified the assessment of soil water availability by relying on soil volumetric water content (VWC) as a primary control on plant growth, which, as opposed to soil water potential (Ψsoil), does not account for the effects of soil texture on plant available water. To address these gaps, we compared remotely sensed indicators of vegetation response to field based …
Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer
Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer
Electronic Theses and Dissertations
Corn (Zea mays L.) is a vital commodity in South Dakota’s agricultural sector. Optimal corn production occurs when there are sufficient mineral nutrients in the soil, especially potassium (K). Applications of K fertilizer are used when soil test K (STK) levels are deficient. Therefore, producers need reliable, thoroughly tested fertilizer recommendations to make profitable decisions and maintain environmental stewardship. South Dakota K fertilizer recommendations have not been updated in nearly 20 years. Simultaneously, changes in corn genetics, management practices, and climate patterns suggest that the critical soil test value (CSTV) for STK may have shifted in that same time frame. …
Non-Linear Modelling Of Internal Geophysical Waves, Joseph Cullen
Non-Linear Modelling Of Internal Geophysical Waves, Joseph Cullen
Doctoral
Geophysical waves are waves that are found naturally in the Earth’s atmosphere and oceans. Internal waves, that act as an interface between fluids of different density are examples of geophysical waves. The system set-up will incorporate a model with a flat bottom, flat surface and internal wave. The system has a depthdependent current which mimics a typical ocean set-up and, as it is based on the surface of the rotating Earth, includes Coriolis forces. Using well established fluid dynamic techniques, the total energy is calculated and used to determine the dynamics of the system using a procedure called the Hamiltonian …
New Advances In Long-Term Monitoring Of Storm-Deposited Boulder Ridges Along Rocky Shorelines Of San Salvador Island, Bahamas, Bosiljka Glumac, Ursula Miquel, H. Allen Curran
New Advances In Long-Term Monitoring Of Storm-Deposited Boulder Ridges Along Rocky Shorelines Of San Salvador Island, Bahamas, Bosiljka Glumac, Ursula Miquel, H. Allen Curran
Geosciences: Faculty Publications
Beginning in January 2012, we have monitored two boulder ridges on San Salvador: Singer Bar Point (SBP, length ~790 m) along the reef- and lagoon-protected northern coast and The Gulf (TG, length ~460 m) on the island’s high-energy southern coast. This long-term monitoring aims at documenting changes in ridge morphology and distribution, and the direction and amount of movement of individual boulders to gain insights into the intensity and effects of storms on these coastal areas.
In the initial stage of our investigations, the largest boulders from each site were photographed, GPS-located, measured, and characterized by composition and morphology. Boulders …
Evaluating The Use Of Environmental Tracers To Reduce Conceptual Model Uncertainty Of Hydrogeologic Models, Andrew Nordberg, Jon Graham, W. Payton Gardner
Evaluating The Use Of Environmental Tracers To Reduce Conceptual Model Uncertainty Of Hydrogeologic Models, Andrew Nordberg, Jon Graham, W. Payton Gardner
Graduate Student Theses, Dissertations, & Professional Papers
Environmental tracer concentrations for CFC12, SF6, and tritium are used in groundwater simulations to assess the ability of these tracers to reduce conceptual model uncertainty due to uncertainty of a site’s geologic and recharge characterization. The resulting groundwater simulations are characterized by site-specific hydrologic and geologic data, and with coordination from a field team with years of knowledge about the site. First-order (conceptual) uncertainty is directly addressed by using a stochastic modeling approach for spatial variability of the proposed subsurface configurations. Simulations of environmental tracer concentrations and water levels are used to assess six alternate conceptual models that are based …
Synthetic Aperture Radar Observations At Salar De Pajonales, Chile, Michael A. A. Mcinenly
Synthetic Aperture Radar Observations At Salar De Pajonales, Chile, Michael A. A. Mcinenly
Graduate Student Theses, Dissertations, & Professional Papers
Remotely sensed microwave radars provide the spatial and temporal coverage needed to improve our understanding of the relationship between moisture content and salt pan mineralogy and, ultimately, climate variability. Moisture content in the surface and near-surface crusts found in salt pan environments, such as salt pan, has a significant impact on the backscatter values recorded by synthetic aperture radar (SAR) systems. This is because moisture affects the dielectric constant and surface roughness of the saline surface, which in turn influences the amount of electromagnetic energy reflected back to the SAR sensor. Changes in backscatter values are attributed to seasonal and …
Beaver Dam Analogs (Bdas) Alter Carbon Pools, Fluxes, And Concentrations Of Intermountain Headwater Streams, Hilary Schultz
Beaver Dam Analogs (Bdas) Alter Carbon Pools, Fluxes, And Concentrations Of Intermountain Headwater Streams, Hilary Schultz
Graduate Student Theses, Dissertations, & Professional Papers
Beaver dam analogs (BDAs) have emerged as a climate adaptation and restoration strategy for water resource management in the drought-prone Western U.S., yet the focus has been on their influence on water quantity, overlooking effects on broader ecological components. By increasing water residence time and facilitating sediment retention, BDAs have the potential to influence carbon pools, fluxes, and concentrations. To examine the influence of BDAs on instream and riparian organic C and trace gases, we studied three intermountain headwater streams restored with BDAs two years after restoration during the summer of 2021. We found that there were subtle differences in …
Climatological, Hydrological, And Economic Analysis Of Agriculture In Montana And The Western U.S.A., Zachary H. Lauffenburger
Climatological, Hydrological, And Economic Analysis Of Agriculture In Montana And The Western U.S.A., Zachary H. Lauffenburger
Graduate Student Theses, Dissertations, & Professional Papers
Many studies have addressed the impact of climate on agriculture; however, fewer studies addressed how farmers adapt to climate change, to what extent implementation of adaptation strategies mitigates economic losses or alters the hydrologic system. Analyses of how historical climate affected not only farmer decision making, but also the economic and hydrological consequences of farmers’ adaptations to climate variations, and projections of the spatiotemporal climatic regimes at finer regional scales are critical for aiding in actionable climate change adaptations. This dissertation helps fill knowledge gaps on the impacts of climate change in rural regions of the agricultural western U.S.A. and …
Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed, Brett J. Oliver
Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed, Brett J. Oliver
Graduate Student Theses, Dissertations, & Professional Papers
We evaluate the sensitivity of Earth's elastic deformation to groundwater hydraulic diffusivity using coupled groundwater and elastic deformation models. Seasonal changes in terrestrial water storage cause deformation to the Earth’s crust and deeper interior that is within the observational capacity of GPS instruments. We couple finite difference groundwater simulations with geodetic forward models of crustal displacement to investigate the ability of geodetic deformation to constrain bedrock hydrologic properties. We use MODFLOW-2005 to simulate seasonal changes in groundwater flow and storage, and then use the LoadDef elastic deformation model to forward model surface displacement caused by the change in terrestrial water …
Carbonates In The Critical Zone, M. D. Covington, J. B. Martin, L. E. Toran, J. L. Macalady, N. Sekhon, P. L. Sullivan, Á. A. García Jr., J. B. Heffernan, W. D. Graham
Carbonates In The Critical Zone, M. D. Covington, J. B. Martin, L. E. Toran, J. L. Macalady, N. Sekhon, P. L. Sullivan, Á. A. García Jr., J. B. Heffernan, W. D. Graham
Geosciences Faculty Publications and Presentations
Earth's Critical Zone (CZ), the near-surface layer where rock is weathered and landscapes co-evolve with life, is profoundly influenced by the type of underlying bedrock. Previous studies employing the CZ framework have focused primarily on landscapes dominated by silicate rocks. However, carbonate rocks crop out on approximately 15% of Earth's ice-free continental surface and provide important water resources and ecosystem services to ∼1.2 billion people. Unlike silicates, carbonate minerals weather congruently and have high solubilities and rapid dissolution kinetics, enabling the development of large, interconnected pore spaces and preferential flow paths that restructure the CZ. Here we review the state …
Hydrologic Outcomes For Ecological Meadow Restoration In The Northern Sierra Nevada, Emma Sevier
Hydrologic Outcomes For Ecological Meadow Restoration In The Northern Sierra Nevada, Emma Sevier
Cal Poly Humboldt theses and projects
Ecologically functioning meadows provide critical ecosystem services including improving a catchment’s water yield, flood dispersion and attenuation, fostering groundwater-dependent ecosystems, and creating natural fire breaks (Loheide and Booth 2011). Degradation from past and current land use has resulted in incised channels that change the magnitude and timing of watershed and meadow fluxes and cause water table decline. Process-based restoration (PBR) is an approach which leverages fluvial processes to increase restoration efficiency. Though PBR is a promising tool to restore degraded meadow ecosystems, more studies are needed to understand its hydrologic outcomes and whether hydrodynamic modeling can be used as a …