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Articles 5521 - 5550 of 9408
Full-Text Articles in Entire DC Network
Linking Historical, Field, And Satellite Data To Determine The Relationship Between Gas Emissions And Vegetation Change In The Puhimau Geothermal Area East Rift Zone Kilauea, Hawaii, Christie Torres Rosa
Linking Historical, Field, And Satellite Data To Determine The Relationship Between Gas Emissions And Vegetation Change In The Puhimau Geothermal Area East Rift Zone Kilauea, Hawaii, Christie Torres Rosa
Dissertations, Master's Theses and Master's Reports
The Puhimau geothermal area, located near the summit of the Kilauea volcano, Hawaii, has been suggested to represent a ‘window’ into the East Rift Zone. The quantification of CO2 and H2S soil gas emissions improves our understanding of its gas emission mode- including total emission and spatial distribution and contribute to a more accurate estimation of total CO2 and H2S in the thermal area – and how these gas emissions relate to observed vegetation health from satellite data. The total emission of CO2 and H2S was interpolated by the sequential Gaussian …
Application Of A Distributed Hydrologic Model For The Analysis Of Land Use Change In Kedougou, Senegal, Francisco Perez
Application Of A Distributed Hydrologic Model For The Analysis Of Land Use Change In Kedougou, Senegal, Francisco Perez
Dissertations, Master's Theses and Master's Reports
West Africa has experienced extensive land use/land cover (LULC) change since the Sahel drought of the 1970s and 80s. Demographic changes, rapid urbanization, and other anthropogenic impacts on land cover in West Africa have potentially altered hydrological regimes. This work was undertaken while I served as a Peace Corps Volunteer in the Kedougou region of Senegal, an area that has experienced significant and rapid infrastructural improvements and urbanization since the early 2000s. The Gambia River flows near Kedougou, where flooding is an extensive problem, making access and livelihood practices difficult during the rainy season. Changes in climate and land use …
Delivering Sustained, Coordinated, And Integrated Observations Of The Southern Ocean For Global Impact, Louise Newman, Petra Heil, Rowan Tebilco, Katsuro Katsumata, Andrew Constable, Esmee Van Wijk, Karen Assmann, Joana Beja, Phillippa Bricher, Richard Coleman, Daniel Costa, Steve Diggs, Riccardo Farneti, Sarah Fawcett, Sarah T. Gille, Katharine R. Hendry, Sian Henly, Eileen Hofmann, Ted Maksym, Matthew Mazloff, Andrew Meijers, Michael M. Meredith, Sebastien Moreau, Burcu Ozsoy, Robin Robertson, Irene Schloss, Oscar Schofield, Jiuxin Shi, Elisabeth Sikes, Inga J. Smith, Sebastiaan Swart, Anna Wahlin, Guy Williams, Michael J. M. Williams, Laura Herraiz-Borreguero, Stefan Kern, Jan Lieser, Robert A. Massom, Jessica Melbourne-Thomas, Patricia Miloslavich, Gunnar Spreen
Delivering Sustained, Coordinated, And Integrated Observations Of The Southern Ocean For Global Impact, Louise Newman, Petra Heil, Rowan Tebilco, Katsuro Katsumata, Andrew Constable, Esmee Van Wijk, Karen Assmann, Joana Beja, Phillippa Bricher, Richard Coleman, Daniel Costa, Steve Diggs, Riccardo Farneti, Sarah Fawcett, Sarah T. Gille, Katharine R. Hendry, Sian Henly, Eileen Hofmann, Ted Maksym, Matthew Mazloff, Andrew Meijers, Michael M. Meredith, Sebastien Moreau, Burcu Ozsoy, Robin Robertson, Irene Schloss, Oscar Schofield, Jiuxin Shi, Elisabeth Sikes, Inga J. Smith, Sebastiaan Swart, Anna Wahlin, Guy Williams, Michael J. M. Williams, Laura Herraiz-Borreguero, Stefan Kern, Jan Lieser, Robert A. Massom, Jessica Melbourne-Thomas, Patricia Miloslavich, Gunnar Spreen
CCPO Publications
The Southern Ocean is disproportionately important in its effect on the Earth system, impacting climatic, biogeochemical, and ecological systems, which makes recent observed changes to this system cause for global concern. The enhanced understanding and improvements in predictive skill needed for understanding and projecting future states of the Southern Ocean require sustained observations. Over the last decade, the Southern Ocean Observing System (SOOS) has established networks for enhancing regional coordination and research community groups to advance development of observing system capabilities. These networks support delivery of the SOOS 20-year vision, which is to develop a circumpolar system that ensures time …
Seasonal Soil Carbon Fluxes In Transitioning Agricultural Soils In Central Washington State: Relations To Land-Use, Environmental Factors And Soil Carbon-Nitrogen Characteristics, Brandon Kautzman
All Master's Theses
Changing agricultural land-use practices to increase soil carbon sequestration contributes to climate change mitigation and improved food security by moving CO2 from the atmosphere into soil as soil organic carbon (SOC). In 2016, a farm in Thorp, Washington, Spoon Full Farm, began converting land historically farmed using conventional methods of tillage and synthetic fertilizers to conservation farming methods with direct seeding and organic soil amendments with a goal of sequestering carbon in the soil. This project evaluates relationships of soil CO2 respiration and net ecological exchange (NEE) with land-use types, seasonal environmental factors (air temperature, relative humidity, soil …
Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona
Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona
All Master's Theses
Records of past tsunamis help constrain the long-term characteristics of megathrust earthquakes and elucidate the role of sea-level in the preservation of tsunami deposits. Near Queule, south-central Chile (39.3˚S, 73.2˚W), three sand layers interpreted as tsunami deposits are interbedded with dark, organic-rich, silt deposits along a tidal channel landward of a sand spit capped by eolian sand dunes. The uppermost sand layer is attributed to the tsunami from the Mw 9.5 1960 earthquake. The sand layer is widespread, tabular, oxidized, thins landward, and generally occurs at a depth of <20 cm. The spatial distribution of the deposit corresponds closely with the extent of the 1960 tsunami sand on 1961 aerial photographs. We computed numerical simulations of the 1960 tsunami in Queule using the GeoClaw finite-slip hydrodynamic model based on three published earthquake sources. The simulations showed inundation up to 4km inland that overtopped the coastal dunes; agreeing with historical documentation and testimonies of 1960 tsunami survivors. Stratigraphically below the 1960 tsunami deposit are two tabular, landward-thinning sand layers with sharp lower contacts above silty organic-rich layers. Combined radiocarbon ages of seeds, charcoal and wood fragments found at the contacts with the underlying organic layers yielded ages of 5460-5320 and 5990-5910 cal. years BP. These sand layers have similar distribution patterns to the 1960 sand layer, but are finer grained, thinner and less oxidized. Below this sequence of interbedded tsunami sands and silty organic layers there is an abrupt contact underlain by a distinct sequence of four inorganic silt layers alternating with dark brown organic-rich silts, which are older than 6280-6110 cal. years BP. The deepest studied layer is a thick, fine, gray sand. We interpret the gray sand as a submarine environment during the mid-Holocene sea-level high stand, and the alternating inorganic and organic silts as tidal to shallow sub-tidal environments, possibly indicating co-seismic land-level changes. Gradual sea level fall after the deposition of the two paleotsunami sand deposits that changed the geomorphology of the coast and limited the accommodation space necessary to preserve additional overwash sediments could explain the 5000-year hiatus with no evidence of earthquakes or tsunamis. Further research will offer possible explanations for the exception of the 1960 tsunami in breaking this long-term pattern.
Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad
Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad
All Master's Theses
The causes and timing of cycles of aggradation and incision in the Hanson Creek drainage in central Washington provide insight into changes in channel morphology and paleoenvironment within the region over the last 8000 years. Stratigraphically and spatially coincident archaeological evidence reveals information related to human occupation during the latter half of the epoch. Using LiDAR imagery and field surveys, recent processes such as degree of modern channel incision, accumulation of valley floor sediment, channel morphology and gradient were evaluated. The spatial distribution of these channel characteristics was assessed in relation to proximal landforms such as colluvial deposits, basalt outcrops, …
Late Devonian Sedimentary Record Of Appalachian Tectonics And Erosion: Geochronology And Geochemistry Of Detrital Muscovite And Zircon From Central Pennsylvania Strata, Cole T. Gardner
Honors Theses
Foreland basin sediment deposition in North-Central Pennsylvania during Late Devonian time records erosion of hinterland source terranes exhumed during regional plate convergence, including the collisional Acadian orogeny. The Catskill clastic wedge preserves a coarsening-upwards stratigraphic succession from marine to fluvial environments associated with sediment progradation and sea-level regression, yet depositional timescales and quantitative provenance data are largely unconstrained.
Detailed facies analysis of eight outcrops spanning >2 km of stratigraphy in Lycoming Co., Pennsylvania documents distinct upsection changes, interpreted to reflect changes in depositional environments consistent with previous sedimentology of the Catskill clastic wedge. Stratigraphy displays a transition from nearshore marine …
Primary Report Of First Documentation Of Mammal Footprints From The Late Oligocene Inthe Sivas Basin, Turkey, Beki̇r Levent Mesci̇, Ahmet Cem Erkman, Şaki̇r Önder Özkurt
Primary Report Of First Documentation Of Mammal Footprints From The Late Oligocene Inthe Sivas Basin, Turkey, Beki̇r Levent Mesci̇, Ahmet Cem Erkman, Şaki̇r Önder Özkurt
Turkish Journal of Earth Sciences
The footprints in this study, which were considered to have been made by ungulates, were discovered on mudstone that was approximately 5 cm thick, near an abundant mud-cracked plane located on the stratigraphic subsurface of the late Oligocene Karayün Formation, which crops out over wide areas in southern Sivas (Turkey) and has terrestrial, fluvial sediment characteristics. These ungulate footprints documented from the late Oligocene of the Karayün Formation in southern Sivas represent the first reported vertebrates in Anatolia. The footprints of three different species of ungulates were identified. The shapes, depth, and widths of the footprints provided some basic ichnotaxonomic …
Florida Science: The Science That Makes Florida Different, Terence W. Cavanaugh
Florida Science: The Science That Makes Florida Different, Terence W. Cavanaugh
Secondary Level Resources
This book was created to assist students with their understanding of how science occurs in Florida. When teaching science or any subject it’s important to remember to begin with the concrete and then move to the abstract. I have found that it has helped my students when I begin by teaching science concepts in a concrete manner and expand from there. For example, when I taught about topographic maps, the students were much more successful in their learning when I started with local topographic maps that included the school and the surrounding area than with places that had mountains or …
Environmental Forensic Characterization Of Former Rail Yard Soils Located Adjacent To The Statue Of Liberty In The New York/New Jersey Harbor, Diane Hagmann, Michael A. Kruge, Matthew Chi-Hymn Cheung, Maria Mastalerz, José Luis Gallego, Jay Prakash Singh, Jennifer Krumins, Xiaona N. Li, Nina M. Goodey
Environmental Forensic Characterization Of Former Rail Yard Soils Located Adjacent To The Statue Of Liberty In The New York/New Jersey Harbor, Diane Hagmann, Michael A. Kruge, Matthew Chi-Hymn Cheung, Maria Mastalerz, José Luis Gallego, Jay Prakash Singh, Jennifer Krumins, Xiaona N. Li, Nina M. Goodey
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Identifying inorganic and organic soil contaminants in urban brownfields can give insights into the adverse effects of industrial activities on soil function, ecological health, and environmental quality. Liberty State Park in Jersey City (N.J., USA) once supported a major rail yard that had dock facilities for both cargo and passenger service; a portion remains closed to the public, and a forest developed and spread in this area. The objectives of this study were to: 1) characterize the organic and inorganic compounds in Liberty State Park soils and compare the findings to an uncontaminated reference site (Hutcheson Memorial Forest); and 2) …
Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp
Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp
Dissertations, Master's Theses and Master's Reports
Boreal peatlands store approximately one third of the earth’s terrestrial carbon, locked away in currently waterlogged and frozen conditions. Peatlands of boreal and arctic ecosystems are affected increasingly by shifting hydrology caused by climate change. The consequences of these relatively rapid ecosystem changes on carbon cycling between the landscape and the atmosphere could provide an amplifying feedback to climate warming. Alternatively, the advancement of terrestrial vegetation into once waterlogged soils could uptake carbon as a sink. Previous work suggests that fens will become an increasingly dominant landscape feature in the boreal. However, studies investigating fens, their response to hydrologic and …
Long-Term Land Management Practices And Their Effect On Soil Health And Crop Productivity, Thomas Joseph Muratore Jr.
Long-Term Land Management Practices And Their Effect On Soil Health And Crop Productivity, Thomas Joseph Muratore Jr.
Theses and Dissertations--Plant and Soil Sciences
Agricultural intensification reliant on monocrops could change soil health in a way that does not support maximum crop productivity. Twenty-nine-year-old no-till field plots at the University of Kentucky Spindletop research farm showed a significant reduction in corn yields from continuous corn plots compared to those from plots in various types of rotation. The objective of this study was to determine what role soil microbes might play in yield reduction and how management and time effects microbial community structure. Samples were collected from the following treatments: continuous corn (CC), continuous soybean (SS), a 2-year corn/soybean rotation (CCSS), Corn in rotation with …
Blue Sky At Midnight - Earthquake Lightning, Neil Whitehead, Ülkü Ulusoy
Blue Sky At Midnight - Earthquake Lightning, Neil Whitehead, Ülkü Ulusoy
Turkish Journal of Earth Sciences
Earthquake light, emerging from the ground as flashes at night (neglecting other more minor forms), usually has a white hemispherical center and blue outer part. The blue resembles daytime blue sky. Its existence is increasingly verified, with about 80 videos on the web to mid-2017. However, the light must be differentiated from power-grid faults, so sound/color/form/length criteria were developed in this paper through examination of many videos. Light should be coseismic (i.e. when the S-waves arrive), hemispherical, not during a storm, less than 1 s long, without fire or smoke, and without many rapid color changes. Warnings about camera artifacts …
Compound-Specific Isotope Analysis Of Amino Acids In Biological Tissues: Applications In Forensic Entomology, Food Authentication And Soft-Biometrics In Humans, Mayara Patricia Viana De Matos
Compound-Specific Isotope Analysis Of Amino Acids In Biological Tissues: Applications In Forensic Entomology, Food Authentication And Soft-Biometrics In Humans, Mayara Patricia Viana De Matos
Graduate Theses, Dissertations, and Problem Reports (ETD)
In this work we demonstrate the power of compound-specific isotope analysis (CSIA) to analyze proteinaceous biological materials in three distinct forensic applications, including: 1) linking necrophagous blow flies in different life stages to their primary carrion diet; 2) identifying the harvesting area of oysters for food authentication purposes; and 3) the ability to predict biometric traits about humans from their hair.
In the first application, we measured the amino-acid-level fractionation that occurs at each major life stage of Calliphora vicina (Robineau-Desvoidy) (Diptera: Calliphoridae) blow flies. Adult blow flies oviposited on raw pork muscle, beef muscle, or chicken liver. Larvae, pupae …
Radar Quantification, Temporal Analysis And Influence Of Atmospheric Conditions On A Roost Of American Robins (Turdus Migratorius) In Oklahoma, Matthew S. Van Den Broeke
Radar Quantification, Temporal Analysis And Influence Of Atmospheric Conditions On A Roost Of American Robins (Turdus Migratorius) In Oklahoma, Matthew S. Van Den Broeke
Department of Earth and Atmospheric Sciences: Faculty Publications
Radar observations present a way to monitor large, mobile populations across long temporal scales, and are especially valuable when individual scatterers are challenging to count visually. The focus of this study is a large and relatively homogeneous wintertime roost of American Robins (Turdus migratorius) in central Oklahoma. Radar observations are used to estimate the roost population through winter 2010–2011, and the population time series is related to weather variables and radar beam propagation. Radar-estimated roost population gradually increased to an estimated peak of 1.5–2 million individuals from November 2010 to January 2011, and then decreased in a more …
Plant Root Systems Preserved In The Permian Cedar Mesa Sandstone At Moki Dugway, Southeastern Utah, David Loope
Plant Root Systems Preserved In The Permian Cedar Mesa Sandstone At Moki Dugway, Southeastern Utah, David Loope
Department of Earth and Atmospheric Sciences: Faculty Publications
Rooted green plants represent the base of the food chain for most terrestrial ecosystems, but, compared to animal burrows, root systems are relatively rarely recognized in ancient sedimentary rocks. Plant roots that penetrate unconsolidated sand dunes, especially those containing not only quartz grains, but also abundant grains of calcite (CaCO3), are commonly replaced by fine crystals of calcite (Klappa, 1980). These structures (known by geologists as rhizoliths from the Greek for “root rock”) are one form of calcite cemented soil and sediment called caliche (figure 1). Caliche crystallizes well above the water table and its calcite crystals are …
Ecosystem Processes, Land Cover, Climate, And Human Settlement Shape Dynamic Distributions For Golden Eagle Across The Western Us, J.D. Tack, B.R. Noon, Z.H. Bowen, B.C. Fedy
Ecosystem Processes, Land Cover, Climate, And Human Settlement Shape Dynamic Distributions For Golden Eagle Across The Western Us, J.D. Tack, B.R. Noon, Z.H. Bowen, B.C. Fedy
United States Geological Survey: Staff Publications
Species–environment relationships for highly mobile species outside of the breeding season are often highly dynamic in response to the collective effects of everchanging climatic conditions, food resources, and anthropogenic disturbance. Capturing dynamic space-use patterns in a model-based framework is critical as model inference often drives place-based conservation planning. We applied dynamic occupancy models to broad-scale golden eagle Aquila chrysaetos survey data collected annually from 2006 to 2012 during the late summer post-fledging period in the western US. We defined survey sites as 10 km transect segments with a 1 km buffer on either transect side (n = 3540). Derived estimates …
Promoting Change In Common Tern (Sterna Hirundo) Nest Site Selection To Minimize Construction Related Disturbance., Peter C. Mcgowan, Jeffery D. Sullivan, Carl R. Callahan, William Schultz, Jennifer L. Wall, Diann J. Prosser
Promoting Change In Common Tern (Sterna Hirundo) Nest Site Selection To Minimize Construction Related Disturbance., Peter C. Mcgowan, Jeffery D. Sullivan, Carl R. Callahan, William Schultz, Jennifer L. Wall, Diann J. Prosser
United States Geological Survey: Staff Publications
Due to the many challenges facing waterbird populations (Jia et al. 2018, Wetlands International 2018), it has become common practice to limit disturbance to breeding colonies whenever possible to maximize reproductive success. While this may require often unpopular management techniques including beach closures (Jorgensen et al. 2015, Mayo et al. 2015) and predator removal (Neuman et al. 2004, Stocking et al. 2017), such actions are sometimes necessary for the success of the colony. However, there are instances when eliminating disturbance is not possible and birds must be attracted to a new site. A common method for attracting waterbirds to a …
Assessment Of Chronic Low-Dose Elemental And Radiological Exposures Of Biota At The Kanab North Uranium Mine Site In The Grand Canyon Watershed, Danielle Cleveland, Jo Ellen Hinck, Julia S. Lankton
Assessment Of Chronic Low-Dose Elemental And Radiological Exposures Of Biota At The Kanab North Uranium Mine Site In The Grand Canyon Watershed, Danielle Cleveland, Jo Ellen Hinck, Julia S. Lankton
United States Geological Survey: Staff Publications
High-grade U ore deposits are in various stages of exploitation across the Grand Canyon watershed, yet the effects of U mining on ecological and cultural resources are largely unknown. Wecharacterized the concentrations of Al, As, Bi, Cd, Co, Cu, Fe, Pb, Hg, Mo, Ni, Se, Ag, Tl, Th, U, and Zn, gross alpha and beta activities, and U and Th radioisotopes in soil, vegetation (Hesperostipa comata, Artemisia tridentata, Tamarix chinensis), and rodents (Peromyscus maniculatus, P. boylii) to waste material at the Kanab North mine, a mine with decades-long surficial contamination, and compared the concentrations (P<0.01) to those at a premining site (Canyon Mine). Rodent tissues were also analyzed for radium-226 and microscopic lesions. Radioactivities and some elemental concentrations (e.g., Co, Pb, U) were greater in the Kanab North mine biological samples than in Canyon Mine biota, indicating a mining-related elemental signature. Mean rodent Ra-226 (111 Bq/kg dry weight [dry wt]) was 3 times greater than expected, indicating radioactive disequilibrium. Multiple soil sample U concentrations exceeded a screening benchmark, growth inhibition thresholds for sensitive plants, and an EC20 for a soil arthropod. Lesions associated with metals exposure were also observed more frequently in rodents at Kanab North than those at Canyon Mine but could not be definitively attributed to U mining. Our results indicate that Kanab North biota have taken up U mining-related elements owing to chronic exposure to surficial contamination. However, no literature-based effects thresholds for small rodents were exceeded, and only a few soil and vegetation thresholds for sensitive species were exceeded; therefore, adverse effects to biota from U mining-related elements at Kanab North are unlikely despite chronic exposure.
Influence Of Ligand Complexation On Nickel Toxicity, Speciation And Bioavailability In Marine Waters, Samantha Sherman
Influence Of Ligand Complexation On Nickel Toxicity, Speciation And Bioavailability In Marine Waters, Samantha Sherman
Theses and Dissertations (Comprehensive)
Currently there are no site-specific bioavailability-based prediction models for assessing the impacts of nickel (Ni) in marine environments although there are indications that these may be warranted. The aim of this research was to characterize the complexation of Ni in relation to toxicity and speciation. Various complexing ligands were used, and it was predicted that the binding affinity (logKf) of ligands would be inversely correlated to toxicity based on dissolved Ni concentrations ([NiD]) but that on a free ion concentration ([Ni2+]) basis, toxicity would not vary. A two-phased approach was used; the first was a proof of principle where synthetic …
Morphometric Analysis Of Subfossil Macronycteris Spp. (Chiroptera: Hipposideridae) From Madagascar, Jamie Lynn Alumbaugh
Morphometric Analysis Of Subfossil Macronycteris Spp. (Chiroptera: Hipposideridae) From Madagascar, Jamie Lynn Alumbaugh
Graduate Research Theses & Dissertations
Macronycteris bats are morphologically conservative between species but demonstrate intraspecific morphological variation between geographic locations and sexes. Two of the four living species of Macronycteris are found on Madagascar, where they are broadly distributed and demonstrate a trend in body size correlated with the latitudinal precipitation cline on the western side of the island. The presence of an extinct species, M. besaoaka, from Anhjohibe Cave in northern Madagascar suggests that Macronycteris was once more diverse, at least with respect to morphology. Since its description, taxonomic and phylogenetic revisions have reshaped our understanding of this genus. On Madagascar, these include the …
Chondrichthyan Diversity Within The Burlington-Keokuk Fish Bed Of Southeast Iowa And Northwest Illinois (Mississippian: Osagean), Matthew Michael James Hoenig
Chondrichthyan Diversity Within The Burlington-Keokuk Fish Bed Of Southeast Iowa And Northwest Illinois (Mississippian: Osagean), Matthew Michael James Hoenig
Browse all Theses and Dissertations
Chondrichthyan remains occur in abundance within a thin layer of limestone at the top of the Burlington Limestone at the point of the contact with the overlying Keokuk Limestone. This layer of rock, the "Burlington-Keokuk Fish Bed," is stratigraphically consistent and laterally extensive in exposures of the Burlington Limestone near its type section along the Iowa-Illinois border. Deposition of the fish bed occurred on the Burlington Continental Shelf carbonate ramp off the subtropical western coast of Laurussia during the Lower Carboniferous (Late Tournaisian; Osagean) due to a drop in sea level, although the specific mechanism(s) that concentrated the vertebrate fossils …
Conservation Agriculture In The Heartland: Farmer Perceptions Of Soil Health And The Adoption Of Cover Crops, Lillian Clarissa Cobo
Conservation Agriculture In The Heartland: Farmer Perceptions Of Soil Health And The Adoption Of Cover Crops, Lillian Clarissa Cobo
Graduate Research Theses & Dissertations
The benefits of cover crops are widely recognized by those interested in conservation agriculture and soil health. These benefits include soil erosion control, nutrient loss reduction, and overall improvement of soil health. However, while these benefits are well-documented, the adoption rate of cover crops in the American Heartland remains astoundingly low. While some studies have attempted to determine the reasons for this low adoption rate, the information relating to how farmer perceptions of soil health impact cover crop adoption is almost nonexistent. Furthermore, there is a clear absence of mixed method studies in the literature relating to this subject. This …
Textile Dyes As A Source Of Groundwater Contamination In Mandalay, Myanmar, Surya Freeman
Textile Dyes As A Source Of Groundwater Contamination In Mandalay, Myanmar, Surya Freeman
Graduate Research Theses & Dissertations
Textile dyeing and weaving of traditional longyi garments has traditionally occurred in the Amarapura Township of Mandalay, Myanmar, since 1822, transitioning from natural to chemical dyes in the early 1900’s. With no current wastewater treatment facilities in Mandalay, dye effluents mix with other wastewaters in unlined canals dug near peoples’ homes and discharge into local canals and groundwater. As locals rely heavily on dug and tube wells for drinking, bathing, and cooking, this industry poses a major health hazard to the people in this region. The objective of this study is to identify the previously unknown composition of the textile …
Water Quality And Small Unmanned Aerial System Photogrammetry Of Boeng Cheung Ek Wastewater Treatment Wetland, Phnom Penh, Cambodia, Samuel Vesal Mallow
Water Quality And Small Unmanned Aerial System Photogrammetry Of Boeng Cheung Ek Wastewater Treatment Wetland, Phnom Penh, Cambodia, Samuel Vesal Mallow
Graduate Research Theses & Dissertations
Boeng Cheung Ek wetland is a large, peri-urban, free water surface, natural wastewater treatment wetland that services approximately 90% of combined storm water and untreated sewage from the city of Phnom Penh, Cambodia, population over 1.5 million. Due to monsoon rainfall and connectivity to the Mekong River, the wetted area cycles between 13 km2 and 20 km2 annually. The objective of this study is to characterize the spatiotemporal variability of contaminants in wetland surface water and groundwater. Dissolved ions including ammonium, nitrate-N (as NO3), phosphate, and chloride, along with E. coli, trace metals, δH, δ18O, and physicochemical parameters were determined …
Structural And Sedimentological Analysis Of The Bear Canyon Conglomerate, Southeastern California: Implications For The Timing And Style Of Miocene Deformation Within The Eastern California Shear Zone, Garrett Goff
Open Access Theses & Dissertations
The region between Indian Pass and Picacho State Recreation Area (PSRA) in southeastern California records complex deformation related to the transition from a Paleogene convergent margin to a Neogene transform setting, although the timing and nature of youngest deformation in this region remains incompletely known. A 1.7 km-thick section of Miocene Bear Canyon conglomerate (BCC) was studied to constrain this young period of deformation. These rocks lie unconformably upon 23 Ma volcanic and epiclastic rocks and a Mesozoic metamorphic basement terrane. Near PSRA the BCC contains locally derived clasts and can be further subdivided into three unconformity-bounded sequences, referred to …
Exploring Dynamic Triggering Of Earthquakes Within The United States & Quaternary Faulting And Urban Seismic Hazards In The El Paso Metropolitan Area, Richard Alexander Alfaro-Diaz
Exploring Dynamic Triggering Of Earthquakes Within The United States & Quaternary Faulting And Urban Seismic Hazards In The El Paso Metropolitan Area, Richard Alexander Alfaro-Diaz
Open Access Theses & Dissertations
Technological advances in combination with the onslaught of data availability allow for large seismic data streams to automatically and systematically be recorded, processed, and stored. Here, we develop an automated approach to identify small, local earthquakes within these large continuous seismic data records. Our aim is to automate the process of detecting small seismic events triggered by a distant large earthquake, recorded at a single station. Specifically, we apply time-domain short-term average (STA) to long-term average (LTA) ratio algorithms to three-component data to create a catalog of detections. We remove some of the false detections by requiring the detection be …
Fishers' Ecological Knowledge And Stable Isotope Analysis: A Social-Ecological Systems Approach To Endangered Species Conservation, Kathryn Rose Wedemeyer-Strombel
Fishers' Ecological Knowledge And Stable Isotope Analysis: A Social-Ecological Systems Approach To Endangered Species Conservation, Kathryn Rose Wedemeyer-Strombel
Open Access Theses & Dissertations
Identifying developmental habitat is essential for understanding population structure and species resiliency, especially for critically endangered species. In long-lived, oceanic, migratory animals such as sea turtles, elucidating developmental grounds is particularly difficult. When data are deficient or challenging to acquire, scientists often lean towards traditional quantitative methods when a social-ecological systems approach could better provide crucial baseline data and guiding information. Fishers ecological knowledge (FEK), the combination of experiential and culturally transmitted knowledge, is expert knowledge and should be treated as such. In 2008, FEK led to the rediscovery of the critically endangered eastern Pacific (EP) population of hawksbill sea …
Detecting Soil Macrofauna Using Ground-Penetrating Radar, Melanie N. Stock, David J. Hart, Nicholas J. Balster
Detecting Soil Macrofauna Using Ground-Penetrating Radar, Melanie N. Stock, David J. Hart, Nicholas J. Balster
Plants, Soils, and Climate Faculty Publications
Fossorial amphibians spend up to ten months belowground, but research into this critical habitat has been impeded by a lack of noninvasive detection methods. Ground-penetrating radar (GPR), however, offers a promising tool because amphibians have theoretically strong electromagnetic (EM) contrasts relative to the soil matrix, and thus potentially high detectability. The objectives of this study were to (1) evaluate GPR by (2) experimentally-inducing three soil thermal regimes that promote stratification in the burrowing depths of 15 Eastern American Toads (Anaxyrus americanus americanus) during the winter of 2011–2012 in Madison, WI, USA. We calculated reflectability and established the unique …
Middle To Late Holocene (7200-2900 Cal. Bp) Archaeological Site Formation Processes At Crumps Sink And The Origins Of Anthropogenic Environments In Central Kentucky, Usa, Justin Nels Carlson
Middle To Late Holocene (7200-2900 Cal. Bp) Archaeological Site Formation Processes At Crumps Sink And The Origins Of Anthropogenic Environments In Central Kentucky, Usa, Justin Nels Carlson
Theses and Dissertations--Anthropology
Though some researchers have argued that the Big Barrens grasslands of Kentucky were the product of anthropogenic land clearing practices by Native Americans, heretofore, this hypothesis had not been tested archaeologically. More work was needed to refine chronologies of fire activity in the region, determine the extent to which humans played a role in the process, and integrate these findings with the paleoenvironmental and archaeological record. With these goals in mind, I conducted archaeological and geoarchaeological investigations at Crumps Sink in the Sinkhole Plain of Kentucky. The archaeological record and site formation history of Crumps Sink were compared with environmental …