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2022

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Articles 6331 - 6360 of 6506

Full-Text Articles in Earth Sciences

Uncertainty Quantification Of Eruption Source Parameters Estimated From Tephra Fall Deposits, R. Constantinescu, J. T. White, C. B. Connor, A. Hopulele-Gligor, S. Charbonnier, J.-C. Thouret, J. M. Lindsay, D. Bertin Jan 2022

Uncertainty Quantification Of Eruption Source Parameters Estimated From Tephra Fall Deposits, R. Constantinescu, J. T. White, C. B. Connor, A. Hopulele-Gligor, S. Charbonnier, J.-C. Thouret, J. M. Lindsay, D. Bertin

School of Geosciences Faculty and Staff Publications

Uncertainty quantification (UQ) in eruption source parameters, like tephra volume, plume height, and umbrella cloud radius, is a challenge for volcano scientists because tephra deposits are often sparsely sampled due to burial, erosion, and related factors. We find that UQ is improved by coupling an advection-diffusion model with two Bayesian inversion approaches: (a) a robust but computationally expensive Generalized Likelihood Uncertainty Estimation algorithm, and (b) a more approximate but inexpensive parameter estimation algorithm combined with first-order, second-moment uncertainty estimation. We apply the two inversion methods to one sparsely sampled tephra fall unit from the 2070 BP El Misti (Peru) eruption …


Impact Of Model Choice In Predicting Urban Forest Storm Damage When Data Is Uncertain, Casey Lambert, Shawn Landry, Michael G. Andreu, Andrew Koeser, Gregory Starr, Christina Staudhammer Jan 2022

Impact Of Model Choice In Predicting Urban Forest Storm Damage When Data Is Uncertain, Casey Lambert, Shawn Landry, Michael G. Andreu, Andrew Koeser, Gregory Starr, Christina Staudhammer

School of Geosciences Faculty and Staff Publications

Research that illuminates causes of urban forest storm damage is valuable for planning and management. However, logistical and safety concerns often delay post-storm surveys in urban areas; thus, surveys may include observations with unverified sources of damage. While this uncertainty is often ignored, it can make up a high proportion of the number of damaged trees. The goal of this research was to improve understanding of techniques for modeling storm damage in urban forests. Using urban forest storm damage inventories collected in Florida, post-Hurricane Irma (2017), we tested how different imputation methods, modeling procedures, and damage frequency levels could impact …


Relative Tectonic Activity Assessment Of The Northern Sumatran Fault From Geomorphological And Morphotectonic Analyses, Aldo Febriansyah Putra Jan 2022

Relative Tectonic Activity Assessment Of The Northern Sumatran Fault From Geomorphological And Morphotectonic Analyses, Aldo Febriansyah Putra

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Northern Sumatran Fault is a part of a trench-parallel strike-slip fault situated in oblique subduction setting. This study aims to assess the relative tectonic activity using geomorphic indices and to interpret the basin-forming mechanisms from geomorphic expressions in order to construct the schematic evolution of the Northern Sumatran Fault based on the development of transverse drainage basins and streams. This study utilized the 8.25-m digital elevation model released by the Geospatial Information Agency, the Republic of Indonesia, namely the DEMNAS. This study applied six geomorphic indices for assessing the relative tectonic activity: mountain-front sinuosity (Smf; average 1.14—1.94), valley width-to-height …


Effect Of Goethite On Arsenic Migration Under Different Ph And Dissolved Organic Carbon Content, Kunchalika Thongmueang Jan 2022

Effect Of Goethite On Arsenic Migration Under Different Ph And Dissolved Organic Carbon Content, Kunchalika Thongmueang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Currently, the problem of detecting various heavy metals is widely observed. It is essential to consider the impact on groundwater. This study aims to investigate the effect of goethite on the mobility of arsenite (As(III)) under different pH conditions, which is divided into 2 parts. In the first part, batch experiments were conducted at different pH levels (pH 4-10) to determine the sorption efficiency for As(III) and goethite (Gt.). Furthermore, the sorption rates of As(III) and Gt., As(III) and Gt. with humic acid (HA), and As(III) and HA were determined at various concentrations (20-100 mg/l As(III)). In the second part, …


2022 Nebraska Water Leaders Academy Final Report, Mark E. Burbach, Robert Matthew Joeckel, Brooke Mott, Gina S. Matkin Jan 2022

2022 Nebraska Water Leaders Academy Final Report, Mark E. Burbach, Robert Matthew Joeckel, Brooke Mott, Gina S. Matkin

Conservation and Survey Division: Faculty and Staff Publications

Fifteen participants completed the 2022 Water Leaders Academy bringing the total number of graduates to 168 since the inception of the program in 2011. Assessments of participants’ transformational leadership skills, champion of innovation skills, water knowledge, engagement with water issues, civic capacity, entrepreneurial leadership behaviors, and boundary spanning skills increased significantly over the course of the year, according to both the participants and their raters. Feedback from the participants was highly positive and constructive. Academy planners are addressing participant concerns. Results of the program assessment indicate that the curriculum is meeting Academy objectives. Therefore, only minor changes are planned for …


High-Tide Floods And Storm Surges During Atmospheric Rivers On The Us West Coast, Christopher G. Piecuch, Sloan Coats, Sönke Dangendorf, Felix W. Landerer, J. T. Reager, Philip R. Thompson, Thomas Wahl Jan 2022

High-Tide Floods And Storm Surges During Atmospheric Rivers On The Us West Coast, Christopher G. Piecuch, Sloan Coats, Sönke Dangendorf, Felix W. Landerer, J. T. Reager, Philip R. Thompson, Thomas Wahl

CCPO Publications

Amospheric rivers (ARs) effect inland hydrological impacts related to extreme precipitation. However, little is known about the possible coastal hazards associated with these storms. Here we elucidate high-tide floods (HTFs) and storm surges during ARs through a statistical analysis of data from the US West Coast during 1980-2016. HTFs and landfalling ARs co-occur more often than expected from random chance. Between 10%-63% of HTFs coincide with landfalling ARs, depending on location. However, only 2%-15% of ARs coincide with HTFs, suggesting that ARs typically must co-occur with anomalously high tides or mean sea levels to cause HTFs. Storm surges during ARs …


Variability And Dynamics Of Along‐Shore Exchange On The West Antarctic Peninsula (Wap) Continental Shelf, Xin Wang, Carlos Moffat, Michael S. Dinniman, John M. Klinck, David A. Sutherland, Borja Aguiar-Gonzáles Jan 2022

Variability And Dynamics Of Along‐Shore Exchange On The West Antarctic Peninsula (Wap) Continental Shelf, Xin Wang, Carlos Moffat, Michael S. Dinniman, John M. Klinck, David A. Sutherland, Borja Aguiar-Gonzáles

CCPO Publications

The continental shelf of the West Antarctic Peninsula (WAP) is characterized by strong along-shore hydrographic gradients resulting from the distinct influences of the warm Bellingshausen Sea to the south and the cold Weddell Sea water flooding Bransfield Strait to the north. These gradients modulate the spatial structure of glacier retreat and are correlated with other physical and biochemical variability along the shelf, but their structure and dynamics remain poorly understood. Here, the magnitude, spatial structure, seasonal-to-interannual variability, and driving mechanisms of along-shore exchange are investigated using the output of a high-resolution numerical model and with hydrographic data collected in Palmer …


Mapping Log Pd/Cu Ratios In Vulcan And Investigation Into The Origin Of The Magenta Zone In The Northmet Deposit: Hoyt Lakes Minnesota, Usa, Paige M. C. M. Bauer Jan 2022

Mapping Log Pd/Cu Ratios In Vulcan And Investigation Into The Origin Of The Magenta Zone In The Northmet Deposit: Hoyt Lakes Minnesota, Usa, Paige M. C. M. Bauer

All Graduate Theses, Dissertations, and Other Capstone Projects

The purpose of this research is to investigate the origin of the PGE-rich Magenta Zone, a geologic feature within the NorthMet Deposit; a Cu-Ni-PGE deposit within a layered intrusion at the base of the 1.1 Ga Duluth Complex. The hypothesis is that a late-stage silicate magma containing dispersed sulfide droplets had infiltrated a permeable crystal mush resulting in the emplacement of the Magenta Zone. While mineralization is typically found along the base of the Duluth Complex, the Magenta Zone lies ~200 m above typical mineralization. Previous research has shown that the Magenta Zone cross cuts the younger concordant units. To …


Stable Isotope Analysis Of A Platecarpus Tympaniticus (Squamata, Mosasauridae) With Actinocamax Sternbergi (Mollsuca, Belemnoidea) Reveals Possible Endothermic Thermoregulation, Mitchell Lukens Jan 2022

Stable Isotope Analysis Of A Platecarpus Tympaniticus (Squamata, Mosasauridae) With Actinocamax Sternbergi (Mollsuca, Belemnoidea) Reveals Possible Endothermic Thermoregulation, Mitchell Lukens

Master's Theses or Doctor of Nursing Practice

Mosasaurs, ancient marine reptiles, dominated the late Cretaceous oceans. However, their ecological success is a contentious topic. Were they ectothermic, like their modern relatives the varanid lizards? Or endothermic like extant marine mammals? Stable isotopes can reveal temperature and physiological variances within skeletons, but do not differentiate between body temperature and ambient environmental temperature. A rare mosasaur specimen from the Smoky Hill Chalk of a partial, articulated Platecarpus tympaniticus with stomach contents of belemnites provides a possible direct temperature contrast between predator and prey. The belemnites, related to modern coleoids, are identified as Actinocamax sternbergi. These animals possessed body …


Dye Tracing And The Effects Of Infrastructure In Hidden River Cave, Horse Cave, Ky, Alexa G. Franks Jan 2022

Dye Tracing And The Effects Of Infrastructure In Hidden River Cave, Horse Cave, Ky, Alexa G. Franks

Master's Theses or Doctor of Nursing Practice

Hidden River Cave is a stream cave system found in Horse Cave, KY with continuous water flow of its two branches, Wheet River and East River. The infrastructure of the city of Hose Cave, KY was originally designed to utilize natural sinkholes for drainage of all wastewaters. The city uses many of these, now modified, sinkholes for wastewater disposal and storm water drainage. Historically, Hidden River Cave has been severely impacted by unmonitored dumping of contamination. To better understand and identify specific flow paths from sinkholes and infrastructure into Hidden River Cave, this study documented various sinkholes and other infrastructure, …


Using Geochemical Composition To Determine Paleo Environmental Conditions And Source Inputs In Paleozoic Rocks Within The Central Kansas Uplift Usa, Christiana Fumnanya Eziashi Jan 2022

Using Geochemical Composition To Determine Paleo Environmental Conditions And Source Inputs In Paleozoic Rocks Within The Central Kansas Uplift Usa, Christiana Fumnanya Eziashi

Master's Theses or Doctor of Nursing Practice

Paleoenvironmental conditions, sediment characteristics and lateral continuity using chemostratigraphy are not well established for stratigraphic units associated with some small fields within the Central Kansas Uplift (CKU). Samples of drill cuttings recovered from six wells (Hottman #1, and Hottman-Furthmeyer#1, Yocemento #1, Mong Benno #2, Rhian #3 and Worcester #1) at 10 ft intervals between 3150 ft and 3900 ft below ground level, were processed and analyzed using X-ray fluorescence (XRF) and X-Ray diffraction (XRD). The XRF technique was used to determine elemental compositions, and XRD was used to determine mineral content. The composition of the rock cuttings was used to …


Application Of Chemostratigraphic Methods To Floodplain Alluvial Deposits Within The Big Harris Creek Basin, North Carolina, Samantha N. Sullivan, Jerry R. Miller, Carmen L. Huffman Jan 2022

Application Of Chemostratigraphic Methods To Floodplain Alluvial Deposits Within The Big Harris Creek Basin, North Carolina, Samantha N. Sullivan, Jerry R. Miller, Carmen L. Huffman

Chemistry & Biochemistry Faculty Publications

Big Harris Creek, North Carolina, possesses a geomorphic history and alluvial stratigraphic record similar to many drainages in southern Appalachian Piedmont. An approximately 1 km reach of Upper Stick Elliott Creek, a tributary to Big Harris Creek, was used herein to (1) explore the use of chemostratigraphic methods to define and correlate late Holocene alluvial deposits along this relatively uncontaminated rural stream containing legacy sediments (historic, anthropogenically derived deposits), and (2) interpret depositional floodplain processes within small (<10 km2), headwater drainages. The lithofacies within four floodplain sections were described in channel banks and sampled at about 5 cm intervals. …


An Analysis Of Associations Between Polarimetric Supercell Signatures, Erik Green Jan 2022

An Analysis Of Associations Between Polarimetric Supercell Signatures, Erik Green

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Supercell thunderstorms produce unique polarimetric radar signatures that are not often observed in unorganized deep convection. Repetitive signatures include deep and persistent differential reflectivity (ZDR) columns and the ZDR arc signature, which are both indicative of thermodynamic and microphysical processes intrinsic to supercells. Prior investigations of supercell polarimetric signatures, both those observed by operational and research radars, and those simulated numerically, reveal positive correlations between the ZDR column depth and cross-sectional area and quantitative characteristics of the radar reflectivity field. This study expands upon prior work by incorporating a dataset of discrete, right moving supercells …


Biochar: Properties And Potential Benefits For Agricultural Soil In Rwanda, Andromede Uwase Jan 2022

Biochar: Properties And Potential Benefits For Agricultural Soil In Rwanda, Andromede Uwase

Honors Program: Senior Projects (Public)

Physical and chemical soil degradation is becoming a major challenge for agricultural productivity in Rwanda, which is the most important part of the country’s economy. The wide spreading soil degradation in Rwanda is mainly a result of naturally poor soils coupled with unsustainable soil management leading to, for example, accelerated soil erosion, acidification, nutrient loss, compaction, and to decreasing yields. Biochar, as an end product of pyrolysis of biomass in the absence of oxygen, has been proposed as a soil amendment in remediation strategies because of its positive effects on soil productivity relevant parameters such as soil pH, structure, nutrient …


Validation Of The Use Of Clathromorphum Compactum Growth And Skeletal Δ18o As A Proxy For Seawater Conditions, Teagan Mcmahon Jan 2022

Validation Of The Use Of Clathromorphum Compactum Growth And Skeletal Δ18o As A Proxy For Seawater Conditions, Teagan Mcmahon

Pitzer Senior Theses

Crustose coralline algae (CCA) are important organisms that create benthic habitat in the photic zone of oceans worldwide. CCAs mechanisms of photosynthesis and calcification may, in some cases, make them vulnerable to climate change and ocean acidification. Therefore, CCA are important not only for their ecological role within ecosystems but also for their ability to indicate the effects that ocean acidification and climate change may have on other marine calcifying organisms. Some species of CCA are known to be useful recorders of paleo oceanic conditions. These climate archives and reconstructions of past environmental conditions are important for understanding past changes …


Thermomechanical Evolution Of A Magmatic System During A Caldera Cycle: Okataina Volcanic Center, New Zealand, Jacob Bonessi Jan 2022

Thermomechanical Evolution Of A Magmatic System During A Caldera Cycle: Okataina Volcanic Center, New Zealand, Jacob Bonessi

Dissertations, Master's Theses and Master's Reports

Caldera forming eruptions represent some of the largest simultaneous releases of mass and energy on the planet and pose a looming risk on a global scale. The study of the underlying magmatic systems is integral in understanding what leads to these large eruptions. This approach pairs a suite of major and trace element profiles from plagioclase with a grain texture classification and statistical analysis using Polytopic Vector Analysis (PVA) as proxies to explore potential changes in the thermomechanical state of the magmatic system at Okataina Volcanic Complex (OVC), New Zealand through its most recent caldera cycle. Results indicate systematic changes …


Estimating Groundnut Yield In Smallholder Agriculture Systems Using Planetscope Data, Daniel Kpienbaareh, Kamaldeen Mohammed, Isaac Luginaah, Jinfei Wang, Rachel Bezner Kerr, Esther Lupafya, Laifolo Dakishoni Jan 2022

Estimating Groundnut Yield In Smallholder Agriculture Systems Using Planetscope Data, Daniel Kpienbaareh, Kamaldeen Mohammed, Isaac Luginaah, Jinfei Wang, Rachel Bezner Kerr, Esther Lupafya, Laifolo Dakishoni

Faculty Publications - Geography, Geology, and the Environment

Crop yield is related to household food security and community resilience, especially in smallholder agricultural systems. As such, it is crucial to accurately estimate within-season yield in order to provide critical information for farm management and decision making. Therefore, the primary objective of this paper is to assess the most appropriate method, indices, and growth stage for predicting the groundnut yield in smallholder agricultural systems in northern Malawi. We have estimated the yield of groundnut in two smallholder farms using the observed yield and vegetation indices (VIs), which were derived from multitemporal PlanetScope satellite data. Simple linear, multiple linear (MLR), …


Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain Jan 2022

Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain

Electronic Theses and Dissertations

Conservation management practice adoption on agricultural land has increased in recent years due to increasing public and private investment. The anticipated impact of increasing conservation management practice adoption are reduced greenhouse gas emissions and improved soil, water, and air quality. Understanding how these conservation management practices affect agricultural producers economically is vital to properly incentivize these practices. The existing literature on how conservation management practices affect soil health and crop yields is mixed and generally has been conducted on experimental research stations. These studies may not fully account for the on-farm effects of conservation management practices. The objectives of this …


Segmentation Of The Wassuk Range Normal Fault System, Nevada (Usa): Implications For Earthquake Rupture And Walker Lane Dynamics, Benjamin E. Surpless, Sarah Thorne Jan 2022

Segmentation Of The Wassuk Range Normal Fault System, Nevada (Usa): Implications For Earthquake Rupture And Walker Lane Dynamics, Benjamin E. Surpless, Sarah Thorne

Earth and Environmental Geosciences Faculty Research

Normal faults are commonly segmented along strike, with segments that localize strain and influence propagation of slip during earthquakes. Although geometry of segments can be constrained by fault mapping, it is challenging to determine seismically relevant segments along a fault zone. Because slip histories, geometries, and strength of linkages between normal fault segments fundamentally control the propagation of rupture during earthquakes, and differences in segment slip rates result in differential uplift of adjacent footwalls, we use along‐ strike changes in footwall morphology to detect fault segments and the relative strength of the mechanical links between them.

We apply a new …


Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead Jan 2022

Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead

Theses and Dissertations--Earth and Environmental Sciences

Coastal wetlands along the Northern Gulf of Mexico (NGOMx) are critically important but threatened environments which provide significant and diverse economic, social, and environmental value. These environments are essential components to the global carbon cycle, serving as one of the most efficient terrestrial carbon sinks. Since onset of the Industrial Revolution increasing rates of coastal wetland loss have been documented due to a variety of anthropogenic activities, neotectonic processes, subsidence, and rising sea-levels. This research utilized an array of methods and sedimentological analyses to test the hypothesis that growth-fault induced changes at Earth’s surface affects the delivery to, and storage …


The Revised Systematics And Paleoecology Of The Devonian Stemless Crinoid Genus Edriocrinus Hall, 1858, Catherine E. Herbert Jan 2022

The Revised Systematics And Paleoecology Of The Devonian Stemless Crinoid Genus Edriocrinus Hall, 1858, Catherine E. Herbert

Theses and Dissertations--Earth and Environmental Sciences

New morphological observations of Edriocrinus Hall, 1858, enable a modern, holistic view of this unusual crinoid genus, previously included in the Superorder Flexibilia (Zittel, 1895) Wright et al., 2017. Re-analysis of Edriocrinus suggests that the genus should now be assigned to the Order ‘Dendrocrinida’ within the Magnorder Eucladida Wright, 2017 based on the five infrabasals, single radianal in the cup, absent anal sac, and non-pinnulate arms with rectangular uniserial brachials. Moreover, examination of the slight variations separating the current 14 Edriocrinus species indicates that these “species” are likely ecophenotypes. The current Edriocrinus species are revised based on firmly bound calyx …


Deformation Of Wall Rocks And Overburden Sequences Proximal To Salt Diapirs In Salt Valley, Utah: Implications For Predicting Subseismic Damage In Salt Tectonic Systems, William Swanger Jan 2022

Deformation Of Wall Rocks And Overburden Sequences Proximal To Salt Diapirs In Salt Valley, Utah: Implications For Predicting Subseismic Damage In Salt Tectonic Systems, William Swanger

Theses and Dissertations--Earth and Environmental Sciences

Although deformation related to salt tectonics is generally considered to be an ancillary field of structural geology, owing to its relatively limited occurrence in the geologic record, the preponderance of salt-involved systems in multiple hydrocarbon-rich basins around the world (e.g., Gulf of Mexico, Atlantic passive margins, Iran, etc.) creates a necessity for understanding salt-related deformation. Traditionally, salt was considered to be relatively weak and thus was mostly unable to drive deformation of adjacent wall rocks and cover sequences. However, a number of recent numerical modeling studies have shown that mobilized and pressurized salt may have the ability to actively pierce …


Tryptophan-Like Fluorescence And Non-Point Source Pollution In Karst Basins, Inner Bluegrass Region, Kentucky, Ryan Dapkus Jan 2022

Tryptophan-Like Fluorescence And Non-Point Source Pollution In Karst Basins, Inner Bluegrass Region, Kentucky, Ryan Dapkus

Theses and Dissertations--Earth and Environmental Sciences

Typically, the degree of fecal contamination of water is assessed by the concentration of thermotolerant coliforms, like E. coli. This method is time-consuming, taking > 18 hours between the start of incubation and subsequent enumeration. The current study examines the utility of monitoring tryptophan-like fluorescence (TLF) using in-situ fluorometers as a proxy for fecal contamination, particularly E. coli. Relative timing of discharge peaks and TLF peaks is considered, as well as differences in E. coli concentrations and major anion concentrations between two different basins that were monitored weekly. Results indicate that TLF is somewhat useful in the prediction of …


Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer Jan 2022

Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer

Theses and Dissertations--Earth and Environmental Sciences

This dissertation is composed of three distinct manuscripts which collectively investigate processes that contribute to the late evolution of collisional mountain systems —specifically, the ancient Appalachian-Caledonian system. In the first paper, 40Ar/39Ar thermochronological data are used to constrain the timing of exhumation of the Scandian orogenic wedge of northern Scotland. Muscovite and amphibole samples yield dates of ca. 420-411 Ma, consistent with cooling after peak orogenesis. During this cooling phase, dates from both systems in individual thrust sheets show an increase in cooling rate in the later stage of exhumation; in the orogenic core, the cooling rate …


Exploration Of Lignin-Based Superabsorbent Polymers (Hydrogels) For Soil Water Management And As A Carrier For Delivering Rhizobium Spp., Toby Adjuik Jan 2022

Exploration Of Lignin-Based Superabsorbent Polymers (Hydrogels) For Soil Water Management And As A Carrier For Delivering Rhizobium Spp., Toby Adjuik

Theses and Dissertations--Biosystems and Agricultural Engineering

Superabsorbent polymers (hydrogels) as soil amendments may improve soil hydraulic properties and act as carrier materials beneficial to soil microorganisms. Researchers have mostly explored synthetic hydrogels which may not be environmentally sustainable. This dissertation focused on the development and application of lignin-based hydrogels as sustainable soil amendments. This dissertation also explores the development of pedotransfer transfer functions (PTFs) for predicting saturated hydraulic conductivity using statistical and machine learning methods with a publicly available large data set. A lignin-based hydrogel was synthesized, and its impact on soil water retention was determined in silt loam and loamy fine sand soils. Hydrogel treatment …


Assessing Machine Learning Utility In Predicting Hydrologic And Nitrate Dynamics In Karst Agroecosystems, Timothy Mcgill Jan 2022

Assessing Machine Learning Utility In Predicting Hydrologic And Nitrate Dynamics In Karst Agroecosystems, Timothy Mcgill

Theses and Dissertations--Biosystems and Agricultural Engineering

Seasonal hypoxia in the Gulf of Mexico and harmful algal blooms experienced in many inland freshwater bodies is partially driven due to excessive nitrogen loading seen from agricultural watersheds. Within the Mississippi/Atchafalaya River Basin, many areas are underlain with karst features, and efforts to reduce nitrogen contributions from these areas have had varying success, due to lacking a complete understanding of nutrient dynamics in karst agricultural systems. To improve the understanding of nitrogen cycling in these systems, 35 months of high resolution in situ water quality and atmospheric data were collected and fed into a two-hidden layer extreme learning machine …


Largemouth Bass In The Upper Mississippi River: An Evaluation Of Management Strategies And Understanding Potential Factors Influencing Dynamic Rate Functions, Kylie Beth Sterling Jan 2022

Largemouth Bass In The Upper Mississippi River: An Evaluation Of Management Strategies And Understanding Potential Factors Influencing Dynamic Rate Functions, Kylie Beth Sterling

Graduate Theses/Dissertations

The Upper Mississippi River (UMR) supports ecologically and economically important commercial and recreational fisheries. One recreational fishery in the UMR is the Largemouth Bass fishery. Recreational fisheries can be effectively managed using information on population dynamics, though little is known about Largemouth Bass population dynamics in large river ecosystems. Therefore, the objectives of this study were to 1) evaluate recruitment, growth, and mortality of three Largemouth Bass populations in the UMR, specifically within Pools 4, 8, and 13, and 2) to use those estimates of recruitment, growth and mortality to inform exploitation models to evaluate best management practices for each …


Investigation Into Karst Of Southwest Missouri Using Electrical Resistivity, Donald Zachary Wormington Jan 2022

Investigation Into Karst Of Southwest Missouri Using Electrical Resistivity, Donald Zachary Wormington

Graduate Theses/Dissertations

Nixa, Missouri is located on the southwestern edge of the Ozark Dome which has a karst geomorphological environment. Near surface geophysical methods can be used in determining the location and nature of karst features such as caves and sinkholes. Electrical resistivity methods have been shown to be among the most useful methods in deciphering sinkholes and caves. To investigate a known cave and related sinkholes and faults within Mississippian carbonates south of Nixa, Missouri, a series of two-dimensional electrical resistivity profiles were collected using the dipole-dipole and Schlumberger arrays. Terrain data was collected to include in modeling. The data were …


U-Pb Apatite Chronometry Of Intrusions In An Accretionary Metamorphic Belt In Western Idaho, Usa, Colleen Grace Rankin Jan 2022

U-Pb Apatite Chronometry Of Intrusions In An Accretionary Metamorphic Belt In Western Idaho, Usa, Colleen Grace Rankin

Graduate Theses/Dissertations

The Salmon River suture zone in west-central Idaho, USA records the tectonic processes where island arcs, similar to modern-day Japan, were accreted to the North American continent in the Jurassic and Cretaceous periods (160-90 million years ago). This suture zone contains metamorphic rocks that were buried deep within the crust at depths of 20 kilometers or more and have subsequently been brought to the surface. The exhuming processes responsible for the metamorphic rocks in the Salmon River suture zone remains unclear. Two competing hypotheses have been proposed to explain the transport of the rocks from the Salmon River suture zone …


Downstream Dispersal Of Fine Tailings, Chat And Metals In Channel Sediment Of Big River, Old Lead Belt, Southeast Missouri, Jennifer Pace Witt Jan 2022

Downstream Dispersal Of Fine Tailings, Chat And Metals In Channel Sediment Of Big River, Old Lead Belt, Southeast Missouri, Jennifer Pace Witt

Graduate Theses/Dissertations

In St. François County, Missouri, compromised above-ground tailings piles and containment ponds from historical mining activities in the Old Lead Belt released considerable amounts of dolomitic, Pb- and Zn-contaminated waste sediments to the Big River, contributing to significant downstream floodplain and channel sediment contamination. Previous studies have documented the effects of heavy metals on Big River biota and water quality, as well as benthic habitat disruption resulting from the influx of small sediments. Few have considered the effects and future contamination risk of the coarse waste sediments (2-16 mm in diameter), locally called “chat”, which retain high Pb and Zn …