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Articles 661 - 690 of 1657
Full-Text Articles in Earth Sciences
Regime Detection Measures For The Practical Ecologist, Jessica L. Burnett
Regime Detection Measures For The Practical Ecologist, Jessica L. Burnett
School of Natural Resources: Dissertations, Theses, and Student Research
Forecasting undesirable change is, arguably, the holy grail of ecology. Paired with an understanding of system interactions, a forecast is ideal if it provides reliable predictions in sufficient time to prevent or mitigate unwanted systemic change. Early warning systems (or early warning signals, early warning indicators) have been developed and tested for some ecological systems data, but have been mostly applied to marine fisheries time series and nutrient loadings in shallow lakes. Despite the numerous quantitative methods proposed for identifying or forecasting regime shifts in ecological data, few are used in practice. This dissertation contributes to our understanding of the …
Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest, Mary G. Keilhauer
Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest, Mary G. Keilhauer
School of Natural Resources: Dissertations, Theses, and Student Research
The Midwestern United States is vulnerable to eutrophic conditions from high nutrient concentrations. Recommendations for nonpoint source pollution management include runoff treatment (i.e., filter strips, riparian buffers) and in-situ lake treatment practices (i.e., aluminum sulfate (alum) treatments, aeration, up/downdraft pumping, floating treatment wetlands). Floating treatment wetlands (FTWs) are an innovative wetland design for nutrient removal from nonpoint sources and provide a unique in-situ treatment. Best management practice studies have commonly focused on adjacent to water practices, which have resulted in a gap for guidance for in-situ treatment placement and design. Therefore, the objectives of this project were to (1) Quantify …
Evaluation Of The Metric Model For Mapping Energy Balance Components And Actual Evapotranspiration For A Super-Intensive Drip-Irrigated Olive Orchard, Samuel Ortega
School of Natural Resources: Dissertations, Theses, and Student Research
A field experiment was carried out to evaluate the METRIC (Mapping EvapoTranspiration at high Resolution Internalized with Calibration) model for mapping net radiation (Rni), soil heat flux (Gi), sensible heat flux (Hi), latent heat flux (LEi), actual evapotranspiration (ETa) and crop coefficient (Kc) of a superintensive drip-irrigated olive (Olea europeae L. cv Arbequina) orchard located in Pencahue Valley, Region del Maule, Chile (35 23’ LS; 71 44’ LW; 96 m above sea level). The study was conducted in an experimental plot of 21.1 hectares using 9 satellite images (Landsat 7 ETM+) acquired on clear sky days during 2011/2012 and 2012/2013 …
Developing A Framework To Link Multi-Sector Drought Impacts To Drought Severity At The State Level, Mary Noel
Developing A Framework To Link Multi-Sector Drought Impacts To Drought Severity At The State Level, Mary Noel
School of Natural Resources: Dissertations, Theses, and Student Research
The United States Drought Monitor, a weekly map depicting severity and spatial extent of drought, is a key indicator for federal and state policy decisions including the annual distribution of hundreds of millions of dollars for agricultural financial relief in the United States. However, the current table describing potential drought impacts for the map’s severity levels fails to adequately represent a state’s unique environmental, economic, and social values affected by drought. One approach to improve this broad, national-scale assessment is to transition from the former platform to a more detailed characterization of drought impacts at the state level. To accomplish …
The Role Of Boundary-Parallel Vertical Wind Shear In Convection Initiation, Alexander J. Krull
The Role Of Boundary-Parallel Vertical Wind Shear In Convection Initiation, Alexander J. Krull
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
Convection initiation (CI) remains a forecasting challenge for meteorologists. CI frequently occurs within the vicinity of some airmass boundary or density current. Airmass boundaries are favored areas of convergence, thus associated forced ascent facilitates CI. Features such as misocyclones often develop along the leading edge of airmass boundaries, favoring updraft formation and prompting alterations to the horizontal and vertical flow near the boundary. Airmass boundary characteristics and CI potential have been found to be sensitive to the environmental vertical wind shear. This affects propagation speed, convergence, and thus forced ascent along the leading edge. Previous studies have focused primarily on …
Supporting Dataset For Chloride Source Delineation In An Urban-Agricultural Watershed, Deicing Agents Versus Agricultural Contributions, Eric Wade Peterson, Andrew Oberhelman
Supporting Dataset For Chloride Source Delineation In An Urban-Agricultural Watershed, Deicing Agents Versus Agricultural Contributions, Eric Wade Peterson, Andrew Oberhelman
Faculty Publications - Geography, Geology, and the Environment
Analyses (n = 535) of chloride (Cl-), bromide (Br-), nitrate as nitrogen (NO3-N), sodium (Na+), calcium (Ca2+), and potassium (K+) in stream water, tile-drain water, and groundwater were conducted in an urban-agricultural watershed (10% urban/impervious, 87% agriculture) to explore potential differences in the signature of Cl- originating from an urban source as compared to an agricultural source. Water samples were collected on a weekly interval from February 2018 to February 2019 at three station along the stream and from tile drains and wells. Nearly all surface water …
Historical Land Use Influence On Fine-Grained Sedimentation In Channel And Floodplain Deposits In A Forested Missouri Ozark Watershed, Katy Nicole Reminga
Historical Land Use Influence On Fine-Grained Sedimentation In Channel And Floodplain Deposits In A Forested Missouri Ozark Watershed, Katy Nicole Reminga
Graduate Theses/Dissertations
Hydrologic disturbances due to land use and climate effects can disrupt river form and increase sediment transport. Ozark streams have been experiencing the effects of accelerated channel erosion on coarse sediment delivery and gravel bar deposition since the onset of early European settlement in the late 1800’s. Little attention has focused on understanding the fate of fine-grained sediment released by upland soil and headwater channel erosion and the potential for storage as legacy deposits on floodplains. Legacy deposits are attributed to human disturbances as the result of land clearing and agriculture that increase runoff, soil erosion, flooding, and sediment supply …
Synthesizing Field And Experimental Techniques To Investigate The Enigmatic Processes Occurring At The Base Of Pyroclastic Currents, Nicholas M. Pollock
Synthesizing Field And Experimental Techniques To Investigate The Enigmatic Processes Occurring At The Base Of Pyroclastic Currents, Nicholas M. Pollock
Boise State University Theses and Dissertations
Pyroclastic currents are the deadliest hazard associated with explosive volcanic eruptions. These gravity-driven currents consist of volcanic gases and solid particles that range in size from fine ash to boulders. The dangers associated with pyroclastic currents stem from their unpredictability and ability to travel extremely long distances, sometimes in excess of 100 km. To mitigate the risk to populations and infrastructure, we must understand the processes that control the runout distance of pyroclastic currents. The runout distance depends on the complex interplay of processes related to sediment transport, erosion, and deposition. Historically, studies focused on understanding sediment transport and deposition, …
Does The Urbanization Of Agricultural Land Lead To More Or Less Evapotranspiration?, Curtis Ryan Crandall
Does The Urbanization Of Agricultural Land Lead To More Or Less Evapotranspiration?, Curtis Ryan Crandall
Boise State University Theses and Dissertations
Agricultural areas within the western U.S. are undergoing rapid urbanization due to population growth. Urban expansion often forces the conversion of adjacent agricultural areas altering the landscape vegetation and associated water consumption through evapotranspiration (ET). The associated difference in ET may alter the landscape water demand complicating water resource management. To investigate these differences, we calculated the agricultural and urban seasonal ET rates in a semiarid watershed currently undergoing large population growth and rapid urbanization. We used high resolution satellite imagery with a GIS computer model to generate basin-wide ET estimates over a 204-day irrigation season. Six land type samples …
Insights Into The Evolution Of The Galápagos Archipelago And Its Mantle Source From Monogenetic Near-Island Seamounts, Darin M. Schwartz
Insights Into The Evolution Of The Galápagos Archipelago And Its Mantle Source From Monogenetic Near-Island Seamounts, Darin M. Schwartz
Boise State University Theses and Dissertations
Lavas erupted at ocean island volcanoes are classically used as probes of the deep Earth, with ultimate goals of discerning the compositional heterogeneity, structure and dynamics of the Earth’s mantle. However, sampling restricted to volcanic islands and large, submarine volcanic constructs alone likely results in limited spatial resolution of the mantle’s composition and structure, owing to homogenization in sub-island magma reservoirs. Further, islands provide poor temporal resolution given that their multigenetic construction can overprint any time progressive chemical variations and they subside with age making detailed sampling difficult. For my dissertation I investigate whether seamounts surrounding islands in the Galápagos …
Response And Recovery Of Horn And Petit Bois Islands, Mississippi, Usa To Tropical Cyclone Impacts: 2004 – 2016, Shara Gremillion
Response And Recovery Of Horn And Petit Bois Islands, Mississippi, Usa To Tropical Cyclone Impacts: 2004 – 2016, Shara Gremillion
Master's Theses
Horn and Petit Bois islands are two of five Mississippi (MS) barrier islands that provide physical protection from tropical cyclones threatening the MS Gulf Coast, in addition to critical habitat for the northern Gulf of Mexico (GOM). In September 2004, Hurricane Ivan removed a large volume of sediment from the eastern ends of Horn and Petit Bois islands with its 1-2 m storm surge and ~194 kph wind speeds. Then, in August 2005 Hurricane Katrina severely impacted the two islands again with its 3.5-5.5 m storm surge on Horn and Petit Bois islands, and up to 204 kph wind speeds …
International Ocean Discovery Program Expedition 382 Preliminary Report: Iceberg Alley And Subantarctic Ice And Ocean Dynamics, Michael E. Weber, Maureen E. Raymo, Trevor Williams, Linda Armbrecht, Ian Bailey, Stefanie Brachfeld, Zhiheng Du, Gerson Fauth, Marga Garcia, Anna Glüder, Michelle Guitard, Marcus Gutjahr, Sidney Hemming, Ivan Hernandez-Almeid, Frida S. Hoem, Ji Hwan Hwang, Mutsumi Iizuka, Yuji Kato, Bridget K. Lee, Yasmina M. Martos, Suzanne O'Connell, Victoria L. Peck, Lara F. Perez, Brendan Reilly, Thomas A. Ronge, Osamu Seki, Lisa Tauxe, Shubham Tripathi, Jonathan Warnock, Xufeng Zheng, Fabricio G. Cardillo, Anthony D. Mello
International Ocean Discovery Program Expedition 382 Preliminary Report: Iceberg Alley And Subantarctic Ice And Ocean Dynamics, Michael E. Weber, Maureen E. Raymo, Trevor Williams, Linda Armbrecht, Ian Bailey, Stefanie Brachfeld, Zhiheng Du, Gerson Fauth, Marga Garcia, Anna Glüder, Michelle Guitard, Marcus Gutjahr, Sidney Hemming, Ivan Hernandez-Almeid, Frida S. Hoem, Ji Hwan Hwang, Mutsumi Iizuka, Yuji Kato, Bridget K. Lee, Yasmina M. Martos, Suzanne O'Connell, Victoria L. Peck, Lara F. Perez, Brendan Reilly, Thomas A. Ronge, Osamu Seki, Lisa Tauxe, Shubham Tripathi, Jonathan Warnock, Xufeng Zheng, Fabricio G. Cardillo, Anthony D. Mello
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
International Ocean Discovery Program (IODP) Expedition 382, Iceberg Alley and Subantarctic Ice and Ocean Dynamics, investigated the long-term climate history of Antarctica, seeking to understand how polar ice sheets responded to changes in insolation and atmospheric CO2in the past and how ice sheet evolution influenced global sea level and vice versa. Five sites (U1534-U1538) were drilled east of the Drake Passage: two sites at 53.2°S at the northern edge of the Scotia Sea and three sites at 57.4°-59.4°S in the southern Scotia Sea. We recovered continuously deposited late Neogene sediment to reconstruct the past history and variability in Antarctic Ice …
A Log And Core Analysis Of The Marmaton Group, Granite Wash Fan Delta In The Anadarko Basin, Washita County, Oklahoma, Cole A. Hatchel
A Log And Core Analysis Of The Marmaton Group, Granite Wash Fan Delta In The Anadarko Basin, Washita County, Oklahoma, Cole A. Hatchel
Electronic Theses and Dissertations
The Pennsylvanian Marmaton Group Granite Wash located in the southern Anadarko Basin is a fan delta system that consists of stacked arkosic sandstones, conglomerates, and shale, and within Washita County, Oklahoma, are known to be a prolific hydrocarbon producer. The Marmaton Group in Washita County, though, has a variable and largely unestablished stratigraphic framework and sudden changes in lithology throughout the region, both horizontally and laterally. This combined with a lack of core or outcrop data has created confusion in the subsurface, and the Marmaton Group has remained largely unstudied in southern Washita County, OK.
This study examined two sets …
Stratigraphic Interpretations Of Eocene Winona And Tallahatta Formations In The Duffee Quadrangle, Ms, Sydney Kennedy
Stratigraphic Interpretations Of Eocene Winona And Tallahatta Formations In The Duffee Quadrangle, Ms, Sydney Kennedy
Honors Theses
Outcrops and exposures of the Winona and Tallahatta formations in the Duffee Quadrangle in Newton and Lauderdale counties were mapped and analyzed. The rock type, composition, structures, and fossils were identified at each site; unit thicknesses were measured, and stratigraphic relationships were analyzed for available exposures. Using GPS coordinates, each site was mapped on Google Earth Pro. The data collected at each site, aerial photographs, and topographic maps were used to identify each formation. The variability between previous works and this study was analyzed. The primary rock type found in the Tallahatta Formation is siliciclastic silty claystone and sandstone; some …
Comparing Structure From Motion Photogrammetry And Computer Vision For Low-Cost 3d Cave Mapping: Tipton-Haynes Cave, Tennessee, Clinton Elmore
Comparing Structure From Motion Photogrammetry And Computer Vision For Low-Cost 3d Cave Mapping: Tipton-Haynes Cave, Tennessee, Clinton Elmore
Electronic Theses and Dissertations
Natural caves represent one of the most difficult environments to map with modern 3D technologies. In this study I tested two relatively new methods for 3D mapping in Tipton-Haynes Cave near Johnson City, Tennessee: Structure from Motion Photogrammetry and Computer Vision using Tango, an RGB-D (Red Green Blue and Depth) technology. Many different aspects of these two methods were analyzed with respect to the needs of average cave explorers. Major considerations were cost, time, accuracy, durability, simplicity, lighting setup, and drift. The 3D maps were compared to a conventional cave map drafted with measurements from a modern digital survey instrument …
Debris-Slide Susceptibility Modelling Using Gis Technology In The Great Smoky Mountains National Park, Raja Das
Electronic Theses and Dissertations
Debris-slides are one of the most frequently occurring geological hazards in metasedimentary rocks of the Anakeesta ridge in Great Smoky Mountains National Park (GRSM), which often depends on the influence of multiple causing factors or geo-factors such as geological structures, slope, topographic elevation, land use, soil type etc. or a combination of these factors. The main objective of the study was to understand the control of geo-factors in initiating debris-slides using different knowledge and data-driven methods in GIS platform. The study was performed in three steps: (1) Evaluation of geometrical relationship between geological discontinuity and topographic orientation in initiation of …
Modeling Extreme Heat Events Using Global Reanalysis Data: An Assessment Of Current Climate Data And The Need For Improved Weather Station Data In Tennessee, John Reasons
Electronic Theses and Dissertations
Wet Bulb Globe Temperature (WBGT) is used to assess categorical heat stress risk factors for individuals working in outdoor environments and to provide guidelines for work/rest ratios and water intake. The variables required to compute WBGT are used by meteorologists for many purposes and are available through the Copernicus Program which was implemented by European Centre for Medium-Range Weather Forecasts (ECMWF) to provide users access to ECMWF Re-Analysis (ERA) historical database. WBGT values for Tennessee during National Weather Service (NWS) issued excessive heat warnings were calculated to determine the need for additional advisories based on WBGT guidelines. Monthly average WBGT …
Evaluating Responses Of Benthic Macrofauna To Artificial Reef Presence In The Gulf Of Mexico, Douglas Faircloth
Evaluating Responses Of Benthic Macrofauna To Artificial Reef Presence In The Gulf Of Mexico, Douglas Faircloth
Theses and Dissertations
Artificial reef research has long concerned itself with the interactions of fishes and has tended to favor commercially valuable species. Because of this, a larger yet less known group that heavily benefits fishes have been overlooked; benthic macrofauna. Benthic macrofauna are marine invertebrates that live below the sediment-water interface and play many roles in the ecosystem. Macrofauna are important prey items, ecosystem engineers, and bioindicators, as well as being ubiquitous in the marine environment. Since macrofauna have been largely ignored in this field, not much is known regarding their interaction with the placement of artificial reefs. To try and fill …
Development Of A Ground-Based Aerial-Tracking Instrument For Open-Path Spectroscopy To Monitor Atmospheric Constituents, Haden Hodges
Development Of A Ground-Based Aerial-Tracking Instrument For Open-Path Spectroscopy To Monitor Atmospheric Constituents, Haden Hodges
Civil Engineering Undergraduate Honors Theses
A ground-based aerial-tracking instrument, known as the Ground Tracker, designed to provide spectral data to quantify greenhouse gases is under development. The Ground Tracker includes an Optical System including a high power rifle scope, video camera, and spectrometer used to locate an active light source from the Emitter, and collect spectral data by utilizing an actuating mirror. The implementation of this instrument could be made low cost by utilizing existing weather balloon infrastructure to allow the Emitter to be placed into the lower stratosphere. The recovery of the emitter will be possible by tracking the GPS coordinates. Weather balloon instrument …
Probabilistic Analysis Of Slide-Rocking Structures Under Earthquake Loads, Taylor J. Knickerbocker
Probabilistic Analysis Of Slide-Rocking Structures Under Earthquake Loads, Taylor J. Knickerbocker
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
Estimates of rare seismic hazard are essential for the resilience of critical infrastructure and facilities. However, these estimates are highly uncertain at long return periods due to the lack of observed earthquake records. Several ground motion prediction equations have been proposed to close this gap and estimate rare seismic demands; however, these models were developed based on more moderate earthquake records and can yield physically unrealizable ground motions when extrapolated to long return periods. For this reason, seismologists have proposed using precariously balanced rocks (PBRs) as a way to constrain rare seismic hazard. PBRs are a type of fragile geologic …
Provenance And Maximum Depositional Age Analysis Of The Moenave Formation Using Detrital Zircon U-Pb Geochronology And Sandstone Petrography, Asher Rea Boudreaux
Provenance And Maximum Depositional Age Analysis Of The Moenave Formation Using Detrital Zircon U-Pb Geochronology And Sandstone Petrography, Asher Rea Boudreaux
Graduate Theses and Dissertations
In southwestern Utah and northeastern Arizona, Moenave Formation (latest Triassic(?)-Jurassic) is bracketed by well-studied Mesozoic units extensively sampled for detrital zircon geochronology and is poorly documented in regard to provenance, representing an important gap in knowledge. The Moenave Formation provides a unique opportunity to employ detrital zircon U-Pb geochronology and sandstone petrography relevant to completing the paleogeographic, evolutionary, and climatic story of the region. This study aims to characterize the sedimentary provenance of the Moenave Formation and to identify, or at least improve constraints on, the stratigraphic position of the Triassic-Jurassic boundary (TJB) and placement of the end-Triassic extinction (ETE), …
Biogeochemical Controls Of Surface Ocean Phosphate, Adam C. Martiny, Michael W. Lomas, Weiwei Fu, Philip W. Boyd, Yuh-Ling L. Chen, Gregory A. Cutter, Michael J. Ellwood, Ken Furuya, Fuminori Hasshihama, Jota Kanda, David M. Karl, Taketoshi Kodama, Qian P. Li, Jian Ma, Thierry Moutin, E. Malcolm S. Woodward, J. Keith Moore
Biogeochemical Controls Of Surface Ocean Phosphate, Adam C. Martiny, Michael W. Lomas, Weiwei Fu, Philip W. Boyd, Yuh-Ling L. Chen, Gregory A. Cutter, Michael J. Ellwood, Ken Furuya, Fuminori Hasshihama, Jota Kanda, David M. Karl, Taketoshi Kodama, Qian P. Li, Jian Ma, Thierry Moutin, E. Malcolm S. Woodward, J. Keith Moore
OES Faculty Publications
Surface ocean phosphate is commonly below the standard analytical detection limits, leading to an incomplete picture of the global variation and biogeochemical role of phosphate. A global compilation of phosphate measured using high-sensitivity methods revealed several previously unrecognized low-phosphate areas and clear regional differences. Both observational climatologies and Earth system models (ESMs) systematically overestimated surface phosphate. Furthermore, ESMs misrepresented the relationships between phosphate, phytoplankton biomass, and primary productivity. Atmospheric iron input and nitrogen fixation are known important controls on surface phosphate, but model simulations showed that differences in the iron-to-macronutrient ratio in the vertical nutrient supply and surface lateral transport …
A Metasomatized Lithospheric Mantle Control On The Metallogenic Signature Of Post-Subduction Magmatism, David A. Holwell, Marco Fiorentini, Iain Mcdonald, Yongjun Lu, Andrea Giuliani, Daniel J. Smith, Manuel Keith, Marek Locmelis
A Metasomatized Lithospheric Mantle Control On The Metallogenic Signature Of Post-Subduction Magmatism, David A. Holwell, Marco Fiorentini, Iain Mcdonald, Yongjun Lu, Andrea Giuliani, Daniel J. Smith, Manuel Keith, Marek Locmelis
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Ore deposits are loci on Earth where energy and mass flux are greatly enhanced and focussed, acting as magnifying lenses into metal transport, fractionation and concentration mechanisms through the lithosphere. Here we show that the metallogenic architecture of the lithosphere is illuminated by the geochemical signatures of metasomatised mantle rocks and post-subduction magmatic-hydrothermal mineral systems. Our data reveal that anomalously gold and tellurium rich magmatic sulfides in mantle-derived magmas emplaced in the lower crust share a common metallogenic signature with upper crustal porphyry-epithermal ore systems. We propose that a trans-lithospheric continuum exists whereby post-subduction magmas transporting metal-rich sulfide cargoes play …
Sand And Pumice Filter Amended With Activated Carbon And Biochar For Phosphorus Retention, James Jihoon Kang, Marissa Davila, Sergio I. Mireles, Jungseok Ho
Sand And Pumice Filter Amended With Activated Carbon And Biochar For Phosphorus Retention, James Jihoon Kang, Marissa Davila, Sergio I. Mireles, Jungseok Ho
School of Earth, Environmental, & Marine Sciences Faculty Publications
Phosphorus (P) loss via stormwater runoff is a water quality concern. The objective of this study was to investigate two commercial biochars relative to an activated carbon as an additive to geomedia (sand and pumice) for P removal. The batch adsorption experiment was conducted to assess P sorption of the geomedia and carbon materials while the leaching experiment was conducted in sand and pumice columns amended with carbon materials (5 % by weight). The batch adsorption test revealed that only activated carbon showed an appreciable P adsorption up to 19 %. Tested biochar materials showed no adsorption capacity for P …
Application Of Semi-Hydrophobic Layers To Decrease Bare Soil Evaporation, Jesse Lee Barnes
Application Of Semi-Hydrophobic Layers To Decrease Bare Soil Evaporation, Jesse Lee Barnes
UNLV Theses, Dissertations, Professional Papers, and Capstones
Evaporative water loss from bare agricultural soils is a primary area of water conservation research. Mulching is the commonly utilized method to decrease evaporative water loss. The most commonly utilized mulch is nonbiodegradable polyethylene sheeting because it tends to decrease evaporative water loss and increase crop yields more than environmentally friendly mulches. This study aimed to test the utility of sand coated with polymerized soybean oil (i.e., hydrophobic sand) as a treatment to reduce bare soil evaporation and an alternative to current practices. Evaporation rates were measured in laboratory soil columns containing both treated and untreated soils. Treatment parameters were …
Developing Multispectral Imaging Techniques To Determine Canopy Coverage And Carbon Storage Of Seagrasses In The Gulf Of Mexico, Ivy Michelle Hinson
Developing Multispectral Imaging Techniques To Determine Canopy Coverage And Carbon Storage Of Seagrasses In The Gulf Of Mexico, Ivy Michelle Hinson
Theses and Dissertations
Although seagrass beds provide global ecosystem services, coverage is in rapid decline, with the capacity of seagrasses to sequester carbon of special concern. Current seagrass monitoring methods are labor intensive and may not offer a complete picture of coverage. Remote sensing offers the ability to oversee landscapes but water in coastal environments presents challenges, as the commonly used near-infrared wavelength dissipates in water.
This project aimed to provide reliable methodology to assess seagrass coverage using multispectral imagery taken from an unmanned aerial vehicle and to provide evidence for the link between seagrass coverage and stored belowground carbon for common seagrasses …
Microbial Community, Functioning, And Its Relationship With Heavy Metals In An Urban Brownfield, Jay Prakash Singh
Microbial Community, Functioning, And Its Relationship With Heavy Metals In An Urban Brownfield, Jay Prakash Singh
Theses, Dissertations and Culminating Projects
The ubiquity of urban brownfields presents a challenge for environmental managers for managing degraded ecosystems that are in close contact with human habitation. Presence of metal contaminants in brownfields further complicate the matters as it cannot be degraded and hence pose a high risk to human and environmental health, and well-being of the local community. However, previous studies indicate that management and restoration of brownfields are possible through the use of low input longer term and sustainable remediation approaches. These sustainable approaches include the use of plants, fungi, and bacteria to increase soil function and mitigate risks from the contaminants. …
Assessment Of Mean Annual Precipitation And Pco₂ Effect On C₃ Land Plant Carbon Isotope Fractionation, Woohee Kim
Assessment Of Mean Annual Precipitation And Pco₂ Effect On C₃ Land Plant Carbon Isotope Fractionation, Woohee Kim
Theses, Dissertations and Culminating Projects
Modern carbon dioxide (CO2) levels are well known from instrumental observation (just exceeded 415 ppmv on May 13th, 2019). CO2 levels (pCO2) in the past, however, are difficult to obtain, especially for geologic time older than 800 thousand years (kyr). Many proxies have been used to infer past CO2 levels in the geologic records, but the results are often incomplete and inconsistent. Here, I assess the uncertainty of a new pCO2 proxy that has great potential to reconstruct continuous pCO2 records across the entire Phanerozoic. This new proxy is based on stable …
Exploring The Role Of Evaporation And Precipitation Rates On Mangrove Island Morphology, Isamar M. CortéS
Exploring The Role Of Evaporation And Precipitation Rates On Mangrove Island Morphology, Isamar M. CortéS
Theses, Dissertations and Culminating Projects
Mangroves are salt tolerant species of trees that grow in tropical and subtropical environments. Mangroves provide ecosystem services to societies along marine environments, including storm protection, coastal biodiversity, and blue carbon storage. However, as the importance of mangrove ecosystems has become clearer over recent years, their coverage has been reduced through mismanagement and climate impacts. For instance, in terms of climate warming, mangroves cannot survive under abnormally high rates of net evaporation when soil stressor concentrations (e.g., sulfate, sulfide) increase above threshold conditions. To study the effects of this climate driver phenomenon on mangrove islands, we are examining mangrove islands, …
The Paleozoic Sedimentary Rocks Of The Ouachita Mountains And Their Genetic Relationship To The Mississippi Valley-Type Mineralization In The Southern Ozark Region: Insights From Radiogenic Pb Isotopes And Trace Elements Studies, Christophe Wakamya Simbo
The Paleozoic Sedimentary Rocks Of The Ouachita Mountains And Their Genetic Relationship To The Mississippi Valley-Type Mineralization In The Southern Ozark Region: Insights From Radiogenic Pb Isotopes And Trace Elements Studies, Christophe Wakamya Simbo
Graduate Theses and Dissertations
Cluster of Pb and/or Zn deposits of the well-known Tri-State and Northern Arkansas Mississippi Valley Type (MVT) districts located north of the Arkoma basin and the Ouachita fold-thrust belt in north America are genetically connected to the Pennsylvanian-Permian Ouachita orogeny which triggered a South-North topographic gradient flow of basinal brines, leaching metal rich sediments en route. The objective of the research is twofold. First, to ascertain whether the organic-rich shales and sandstones from the study area provided metals during the mineralization event, which was coeval with the Ouachita orogeny. Second, to assess the depositional environment of the potential source rocks, …