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Selenium Removal And Pollution Swapping Potentials Of Passive Anaerobic Bioreactors Receiving Coal Slurry Impoundment Wastes, Md Anik Mahmud Jan 2021

Selenium Removal And Pollution Swapping Potentials Of Passive Anaerobic Bioreactors Receiving Coal Slurry Impoundment Wastes, Md Anik Mahmud

Theses and Dissertations--Plant and Soil Sciences

Worldwide, selenium is a major contaminant of concern for coal and metal ore mining industries. In coal mining regions of the eastern USA, for example, billions of liters of wastewaters with elevated Se oxyanion concentrations (primarily SeO42- and SeO32-) are generated during coal washing which is often stored in > 700 man-made impoundments built into remote mountain valleys. Because impoundments are unlined systems, they tend to leak contents into nearby streams, which has detrimental effects on sensitive biota, particularly fish. The primary goal of this project was to evaluate the capacity of passive anaerobic bioreactors (PAB) …

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Late Campanian Larger Benthic Foraminifera From The Zekeriyaköy Formation (İstanbul,Nw Turkey): Taxonomy, Stratigraphy, And Paleogeography, Mert Eren Erdem, Ercan Özcan, Ali̇ Osman Yücel, Aral I. Okay, Sadikcan Erbay, Si̇bel Kayğili, İsak Yilmaz Jan 2021

Late Campanian Larger Benthic Foraminifera From The Zekeriyaköy Formation (İstanbul,Nw Turkey): Taxonomy, Stratigraphy, And Paleogeography, Mert Eren Erdem, Ercan Özcan, Ali̇ Osman Yücel, Aral I. Okay, Sadikcan Erbay, Si̇bel Kayğili, İsak Yilmaz

Turkish Journal of Earth Sciences

North of İstanbul, the thick Upper Cretaceous volcanic and volcanoclastic sequence of the Yemişliçay Group is nonconformably overlain by the neritic clastic and carbonate sequence of the Zekeriyaköy Formation. This unit, either placed within the volcanic sequence or interpreted to overlie it, was studied near Zekeriyaköy for its larger foraminifera, previously recurrently referred to as the Maastrichtian. The basal epiclastic sandstone beds of the Zekeriyaköy Formation immediately above the volcanic sequence contain Praesiderolites dordoniensis and rare rudist shells. The higher sandstone and limestone beds comprise assemblages of Lepidorbitoides campaniensis, Orbitoides megaloformis, Vanderbeekia catalana, Siderolites gr. calcitrapoides, Sirtina orbitoidiformis, Praestorrsella roestae, …

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Investigation Of Defective Trees Using Electric Resistivity Method, Turgay İşseven, Yi̇ği̇t Yilmaz, Nedi̇m Gökhan Aydin Jan 2021

Investigation Of Defective Trees Using Electric Resistivity Method, Turgay İşseven, Yi̇ği̇t Yilmaz, Nedi̇m Gökhan Aydin

Turkish Journal of Earth Sciences

The resistivity method in geophysics is used to solve various geological and engineering problems. Recently, this nondestructive method has been used on trees to investigate possible infections within the trunks by scanning resistivity variations. In this study, the electrical resistivity method has been aimed to be applied on various trees in Istanbul, Turkey to test whether the method applies to trees via regular resistivity measurement devices used in geophysics. Firstly, a multi-channel resistivity device, that is designed to automatically take measurements on the ground, is modified to carry out the measurements on trees. The measured data are processed using two …

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Socioeconomic Challenges Of California Strawberry Production And Disease Resistant Cultivars, Julie Guthman, Estelí Jiménez-Soto Jan 2021

Socioeconomic Challenges Of California Strawberry Production And Disease Resistant Cultivars, Julie Guthman, Estelí Jiménez-Soto

School of Geosciences Faculty and Staff Publications

Strawberries are the 4th highest grossing crop in California and supply 90% of US strawberries. But the industry's long reliance on the use of chemical fumigants to control soil disease, nematodes and weeds is being threatened by increased regulation of these fumigants, leading to urgent efforts to develop and test non-chemical alternatives to fumigation, such as disease resistant cultivars. Many of these technologies are promising ecologically, but making them economically viable for growers is more challenging, especially in light of the socioeconomic context of strawberry production in California that has created a state of lock-in for a sustainability transition. This …

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Soil Response Of Helicopter Liming In The Monongahela National Forest, Jarrett Douglas Fowler Jan 2021

Soil Response Of Helicopter Liming In The Monongahela National Forest, Jarrett Douglas Fowler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Soils in the Monongahela National Forest (MNF) are acidic due to sandstone parent material, acid deposition, uptake of base cations by vegetation, and release of organic acids by organic matter (OM) decomposition. Increases in soil acidity have caused declines in forest health and changed species composition and nutrient status. Liming can neutralize soil acidity, but no large-scale liming projects have been done on acid forest soils in the USA. In anticipation of acquiring funding for a proposed liming project in the MNF, in 2007 and 2009 10 sites were selected to sample and analyze soils before lime was applied. In …

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Sediment Nutrient Dynamics In Fondriest Agricultural Settling Pond, Marie Grace Bezold Jan 2021

Sediment Nutrient Dynamics In Fondriest Agricultural Settling Pond, Marie Grace Bezold

Browse all Theses and Dissertations

Excess loading of nitrogen (N) and phosphorus (P) is a serious global problem and has numerous negative impacts on water quality of aquatic ecosystems including eutrophication, harmful algal blooms, and hypoxia. Anthropogenic activities (such as the Haber-Bosch process, burning of fossil fuels, sewage treatment, and manure reuse) have led to excess N loading to aquatic systems. Sediment N dynamics were examined from Oct 2019 – Oct 2020 in an agricultural settling pond connected to a constructed wetland adjacent to an agricultural field. Intact sediment cores were amended with 15N for continuous-flow incubations to measure denitrification and N fixation rates, as …

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Potential Solar Replacement Of Hydroelectricity To Reopen Rivers: Maine As A Case Example, Shailesh Sharma, John Waldman Jan 2021

Potential Solar Replacement Of Hydroelectricity To Reopen Rivers: Maine As A Case Example, Shailesh Sharma, John Waldman

Publications and Research

Hydroelectricity provides 6% of U.S. electrical power needs, but hydro-dams also cause environmental harm, including the retardation or complete blockage of spawning runs of anadromous fishes. To facilitate fish movements, engineered-fishways have long been used but many have performed poorly. Dam-removal is the most effective way of restoring dwindling migratory fish populations by allowing unrestricted pathways to their spawning areas and for the downstream migrations of post-spawning adults and juveniles. However, removals of hydro-dams result in a loss of electricity production. For the replacement of energy foregone from hydro-dam removals, various alternative energy installations are now feasible. We present one-to-one …

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Internal Loading Of Nitrogen (N) And Phosphorus (P), Reduced N Forms, And Periodic Mixing Support Cyanobacterial Harmful Algal Blooms (Habs) In Shallow, Eutrophic Honeoye Lake (New York, Usa), Justin Adam Myers Jan 2021

Internal Loading Of Nitrogen (N) And Phosphorus (P), Reduced N Forms, And Periodic Mixing Support Cyanobacterial Harmful Algal Blooms (Habs) In Shallow, Eutrophic Honeoye Lake (New York, Usa), Justin Adam Myers

Browse all Theses and Dissertations

Cyanobacteria are important primary producers, but large cyanobacterial harmful algal blooms (HABs) have many negative ecological and health impacts and are becoming increasingly common. Honeoye Lake (New York, USA) is a shallow, eutrophic lake characterized by increasingly frequent HABs. Nitrogen (N) and phosphorus (P) loads often drive HABs in lakes, and sediment processes can contribute to N removal (e.g., denitrification) or loading (e.g., N fixation, remineralization). Sediment cores and lake water were collected during May–October (2016–2018) at two sites and incubated with no amendments (controls) or 15N stable isotopes to measure sediment nutrient fluxes and N cycling dynamics in Honeoye …

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Sediment-Water Fluxes Of Phosphorus And Trace Metals In The Maumee River, Northwest Ohio, Emily L. Holliday Jan 2021

Sediment-Water Fluxes Of Phosphorus And Trace Metals In The Maumee River, Northwest Ohio, Emily L. Holliday

Browse all Theses and Dissertations

Excess phosphorus (P) and nitrogen (N) in the western basin of Lake Erie drive annual cyanobacteria blooms and associated hypoxia events. The Maumee River inputs ~5% of the water load into the western basin and ~50% of annual P loadings. I quantified seasonal variability of net P and metals fluxes from sediments in the Maumee River at four stations from Defiance, Ohio, to Maumee Bay. Upriver sediments were, on average, a total and filtered P sink throughout the year (−19 ± 7 and −6 ± 3, respectively; all fluxes represent `net flux’ reported in µmol m−2 h−1). At the river …

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A Methodology For The Creation Of Volcanic Gas Hazard Maps Using Satellite-Derived Sulfur Dioxide, Sanna J. Mairet Jan 2021

A Methodology For The Creation Of Volcanic Gas Hazard Maps Using Satellite-Derived Sulfur Dioxide, Sanna J. Mairet

Dissertations, Master's Theses and Master's Reports

Sulfur dioxide (SO2) gas has been shown to be detrimental to human and environmental health and is emitted continuously from anthropogenic and volcanic sources. Sulfur dioxide is the main target gas used for the detection of hazardous volcanic plumes due to its ease of detection by satellite sensors. However, quantitative information on potential ground-level exposure to volcanic SO2 (i.e., a volcanic gas ‘hazard map’) is currently unavailable for the vast majority of active volcanoes. Utilizing sulfur dioxide vertical column densities retrieved from the Ozone Monitoring Instrument on NASA’s Aura satellite, Gridded Population of the World v.4, planetary …

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Influence Of Irrigation Drivers Using Boosted Regression Trees: Kansas High Plains, Susan E. Lamb, Erin M.K. Haacker, Samuel J. Smidt Jan 2021

Influence Of Irrigation Drivers Using Boosted Regression Trees: Kansas High Plains, Susan E. Lamb, Erin M.K. Haacker, Samuel J. Smidt

Department of Earth and Atmospheric Sciences: Faculty Publications

Groundwater levels across parts of western Kansas have been declining at unsustainable rates due to pumping for agricultural irrigation despite water-saving efforts. Accelerating this decline is the complex agricultural landscape, consisting of both categorical (e.g., management boundaries) and numerical (e.g., crop prices) factors that drive irrigation decisions, making integrated water budget management a challenge. Furthermore, these factors frequently change through time, rendering management strategies outdated within relatively short time scales. This study uses boosted regression trees to simultaneously analyze categorical and numerical data against annual irrigation pumping to determine the relative influence of each factor on groundwater pumping across both …

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Terrestrial Ecological Risk Analysis Via Dietary Exposure At Uranium Mine Sites In The Grand Canyon Watershed (Arizona, Usa), Jo Ellen Hinck, Danielle Cleveland, Bradley E. Sample Jan 2021

Terrestrial Ecological Risk Analysis Via Dietary Exposure At Uranium Mine Sites In The Grand Canyon Watershed (Arizona, Usa), Jo Ellen Hinck, Danielle Cleveland, Bradley E. Sample

United States Geological Survey: Staff Publications

The U.S. Department of the Interior recently included uranium (U) on a list of mineral commodities that are considered critical to economic and national security. The uses of U for commercial and residential energy production, defense applications, medical device technologies, and energy generation for space vehicles and satellites are known, but the environmental impacts of uranium extraction are not always well quantified. We conducted a screening-level ecological risk analysis based on exposure to miningrelated elements via diets and incidental soil ingestion for terrestrial biota to provide context to chemical characterization and exposures at breccia pipe U mines in northern Arizona. …

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Metabarcoding Assays For The Detection Of Freshwater Mussels (Unionida) With Environmental Dna, Katy E. Klymus, Catherine A. Richter, Nathan Thompson, Jo Ellen Hinck, Jess W. Jones Jan 2021

Metabarcoding Assays For The Detection Of Freshwater Mussels (Unionida) With Environmental Dna, Katy E. Klymus, Catherine A. Richter, Nathan Thompson, Jo Ellen Hinck, Jess W. Jones

United States Geological Survey: Staff Publications

Freshwater mussels of the order Unionida are a widely distributed taxon that are important in maintaining freshwater ecosystems and are also highly imperiled throughout the world. Monitoring of mussel populations with environmental DNA (eDNA) is an attractive alternative to traditional methods because it is noninvasive and requires less labor and taxonomic knowledge from field personnel. We developed eDNA metabarcoding assays specific to freshwater mussels and tested them at six sites in the Clinch River, located in the southeastern United States. Our objective was to determine the utility of eDNA metabarcoding for future monitoring of mussel populations and restoration efforts in …

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How Wetland Plants Deal With Stress, Taylor M. Sloey Jan 2021

How Wetland Plants Deal With Stress, Taylor M. Sloey

Biological Sciences Faculty Publications

We all get stressed. To deal with that stress, some of us may exercise, take a bubble bath, cry, or simply leave the stressful situation. But how can you cope with stress if you are rooted in place? Plants that live in estuaries are exposed to many types of stresses from the environment, including flooding, high salt levels, low soil oxygen, and waves. Fortunately, wetland plants have developed ways to survive within these conditions, from excreting salt, to growing faster, to even breaking down cell walls to maximize air flow. Plants can tolerate different levels of stress depending on their …

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Nanomaterials In The Environment, Human Exposure Pathway, And Health Effects: A Review, Arindam Malakar, Sushil R. Kanel, Chittaranjan Ray, Daniel D. Snow, Mallikarjuna N. Nadagouda Jan 2021

Nanomaterials In The Environment, Human Exposure Pathway, And Health Effects: A Review, Arindam Malakar, Sushil R. Kanel, Chittaranjan Ray, Daniel D. Snow, Mallikarjuna N. Nadagouda

Daugherty Water for Food Global Institute: Faculty Publications

Nanomaterials (NMs), both natural and synthetic, are produced, transformed, and exported into our environment daily. Natural NMs annual flux to the environment is around 97% of the total and is significantly higher than synthetic NMs. However, synthetic NMs are considered to have a detrimental effect on the environment. The extensive usage of synthetic NMs in different fields, including chemical, engineering, electronics, and medicine, makes them susceptible to be discharged into the atmosphere, various water sources, soil, and landfill waste. As ever-larger quantities of NMs end up in our environment and start interacting with the biota, it is crucial to understand …

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Baseflow Nitrate Dynamics Within Nested Watersheds Of An Agricultural Stream In Nebraska, Usa, Galen Richards, Troy E. Gilmore, Aaron R. Mittelstet, Tiffany Messer, Daniel D. Snow Jan 2021

Baseflow Nitrate Dynamics Within Nested Watersheds Of An Agricultural Stream In Nebraska, Usa, Galen Richards, Troy E. Gilmore, Aaron R. Mittelstet, Tiffany Messer, Daniel D. Snow

Daugherty Water for Food Global Institute: Faculty Publications

There is a need to evaluate high surface nitrate concentrations across agricultural watersheds, both spatially and temporally, to increase understanding of source and timing of nitrogen loads in streams and rivers. Bazile Creek is a high-nitrate stream originating in the agriculturally intensive Bazile Groundwater Management Area of Eastern Nebraska, USA. It is a gaining stream that receives groundwater with high nitrate concentrations originating from nonpoint sources. The objective of this study was to determine spatial and temporal variability of baseflow nitrate concentrations in Bazile Creek and its tributaries and to relate this variability to watershed characteristics. Surface-water nitrate samples were …

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Surveillance Of Plasticizers, Bisphenol A, Steroids And Caffeine In Surface Water Of River Ganga And Sundarban Wetland Along The Bay Of Bengal: Occurrence, Sources, Estrogenicity Screening And Ecotoxicological Risk Assessment, Paromita Chakraborty, Nancy W. Shappell, Moitraiyee Mukhopadhyay, Sathaporn Onanong, Daniel D. Snow Jan 2021

Surveillance Of Plasticizers, Bisphenol A, Steroids And Caffeine In Surface Water Of River Ganga And Sundarban Wetland Along The Bay Of Bengal: Occurrence, Sources, Estrogenicity Screening And Ecotoxicological Risk Assessment, Paromita Chakraborty, Nancy W. Shappell, Moitraiyee Mukhopadhyay, Sathaporn Onanong, Daniel D. Snow

Daugherty Water for Food Global Institute: Faculty Publications

The transboundary River Ganga serves as a conduit for meltwater from the Himalayas and is a major freshwater source for two thirds of Indian population before emptying into the Sundarban Delta, the largest estuary in the Bay of Bengal. Endocrine disrupting compounds (EDCs) such as phthalic acid esters (PAEs) and bisphenol A (BPA) used as organic plastic additives can pollute the aquatic environment receiving plastic litter. Hence, we have investigated these EDCs in water samples from Ganga and Sundarban wetland of India. Since these compounds exhibit estrogenic potential, we have further measured steroids and evaluated the estrogenic activity (estradiol equivalents, …

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Transmission Routes Of The Microbiome And Resistome From Manure To Soil And Lettuce, Yuepeng Sun, Daniel D. Snow, Harkamal Walia, Xu Li Jan 2021

Transmission Routes Of The Microbiome And Resistome From Manure To Soil And Lettuce, Yuepeng Sun, Daniel D. Snow, Harkamal Walia, Xu Li

Daugherty Water for Food Global Institute: Faculty Publications

The land application of animal manure can introduce manure microbiome and resistome to croplands where food crops are grown. The objective of this study was to characterize the microbiome and resistome on and in the leaves of lettuce grown in manured soil and identify the main transmission routes of microbes and antibiotic resistance genes (ARGs) from soil to the episphere and endosphere of lettuce. Shotgun metagenomic results show that manure application significantly altered the composition of the microbiome and resistome of surface soil. SourceTracker analyses indicate that manure and original soil were the main source of the microbiome and resistome …

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Topographic Gradients In Bulk Soil Properties In Central Kentucky Karst Sinkholes, Anne Kathryn Mcgraw Jan 2021

Topographic Gradients In Bulk Soil Properties In Central Kentucky Karst Sinkholes, Anne Kathryn Mcgraw

Theses and Dissertations--Plant and Soil Sciences

The Bluegrass physiographic region of Kentucky is underlain by the late Ordovician Lexington Limestone formation. This area has many identifiable karst features, including sinkholes. Karst sinkholes and associated soils coevolve, which may influence the distribution of bulk soil properties and storage of carbon across karst landscapes. Two sinkholes on the University of Kentucky’s C. Oran Little Animal Research Center in Woodford County, central Kentucky, were selected for analysis. We described and sampled nine pedons at the dominant landscape positions (e.g., summit, shoulder, backslope, footslope, and toeslope) within the two sinkholes; we characterized the physical, chemical, and mineralogical soil properties across …

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Diversity And Taxonomy Of Malagasy Pygmy Hippopotamuses, Allison Shackelton Jan 2021

Diversity And Taxonomy Of Malagasy Pygmy Hippopotamuses, Allison Shackelton

Graduate Research Theses & Dissertations

Madagascar has many species of extinct megafauna, including up to three species of extinct hippopotamus. Subfossil hippo specimens have been found at sites across Madagascar, yet the number of species and taxonomic relationships of the extinct Malagasy pygmy hippopotamus are poorly understood. This thesis will analyze cranial and postcranial bones to improve our understanding of the diversity and taxonomy of Malagasy subfossil hippos, focusing on adults from Ampasambazimba and Tsaramody and juveniles from Ampasambazimba and Anjohibe. Measurements of the tibia and femur of adult specimens, which are used as diagnostic features in other studies, may not be accurate diagnostic features, …

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Quantifying Bedrock Recharge In Two Paired Mountainous Watersheds, Kimberly Bolhuis Jan 2021

Quantifying Bedrock Recharge In Two Paired Mountainous Watersheds, Kimberly Bolhuis

Graduate Student Theses, Dissertations, & Professional Papers

This study focuses on 1) estimating the magnitude of bedrock recharge and 2) mean transit time as a function of bedrock permeability in two paired catchments underlain by different lithology. Networks of bedrock wells and stream gauges were installed in two adjacent catchments of approximately the same size in west central Montana. Fracture network properties for both lithologies were characterized from borehole core logging and scan lines on exposed outcrop. Recharge was evaluated using the Water Table Fluctuation (WTF) method on bedrock well hydrographs installed in both catchments. Stable water isotope samples, collected approximately monthly, from precipitation and stream water …

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Connectivity: Insights From The U.S. Long Term Ecological Research Network, David M. Iwaniec, Michael Gooseff, Katharine N. Suding, David Samuel Johnson, Daniel C. Reed, Debra P. C. Peters, Byron Adams, John E. Barrett, Brandon T. Bestelmeyer, Max C. N. Castorani, Elizabeth M. Cook, Melissa J. Davidson, Peter M. Groffman, Niall P. Hanan, Laura F. Huenneke, Pieter T. J. Johnson, Diane M. Mcknight, Robert J. Miller, Gregory S. Okin, Daniel L. Preston, Andrew Rassweiler, Chris Ray, Osvaldo E. Sala, Robert L. Schooley, Timothy Seastedt, Marko J. Spasojevic, Enrique R. Vivoni Jan 2021

Connectivity: Insights From The U.S. Long Term Ecological Research Network, David M. Iwaniec, Michael Gooseff, Katharine N. Suding, David Samuel Johnson, Daniel C. Reed, Debra P. C. Peters, Byron Adams, John E. Barrett, Brandon T. Bestelmeyer, Max C. N. Castorani, Elizabeth M. Cook, Melissa J. Davidson, Peter M. Groffman, Niall P. Hanan, Laura F. Huenneke, Pieter T. J. Johnson, Diane M. Mcknight, Robert J. Miller, Gregory S. Okin, Daniel L. Preston, Andrew Rassweiler, Chris Ray, Osvaldo E. Sala, Robert L. Schooley, Timothy Seastedt, Marko J. Spasojevic, Enrique R. Vivoni

Advanced Science Research Center

Ecosystems across the United States are changing in complex and surprising ways. Ongoing demand for critical ecosystem services requires an understanding of the populations and communities in these ecosystems in the future. This paper represents a synthesis effort of the U.S. National Science Foundation-funded Long-Term Ecological Research (LTER) network addressing the core research area of “populations and communities.” The objective of this effort was to show the importance of long-term data collection and experiments for addressing the hardest questions in scientific ecology that have significant implications for environmental policy and management. Each LTER site developed at least one compelling case …

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Cascading Effects: Insights From The U.S. Long Term Ecological Research Network, Christie A. Bahlai, Clarisse Hart, Maria T. Kavanaugh, Jeffrey D. White, Roger W. Ruess, Todd J. Brinkman, Hugh W. Ducklow, David R. Foster, William R. Fraser, Hélène Genet, Peter M. Groffman, Stephen K. Hamilton, Jill F. Johnstone, Knut Kielland, Douglas A. Landis, Michelle C. Mack, Orlando Sarnelle, Jonathan R. Thompson Jan 2021

Cascading Effects: Insights From The U.S. Long Term Ecological Research Network, Christie A. Bahlai, Clarisse Hart, Maria T. Kavanaugh, Jeffrey D. White, Roger W. Ruess, Todd J. Brinkman, Hugh W. Ducklow, David R. Foster, William R. Fraser, Hélène Genet, Peter M. Groffman, Stephen K. Hamilton, Jill F. Johnstone, Knut Kielland, Douglas A. Landis, Michelle C. Mack, Orlando Sarnelle, Jonathan R. Thompson

Advanced Science Research Center

Ecosystems across the United States are changing in complex and unpredictable ways and analysis of these changes requires coordinated, long-term research. This paper is a product of a synthesis effort of the U.S. National Science Foundation funded Long-Term Ecological Research (LTER) network addressing the LTER core research area of “populations and communities.” This analysis revealed that each LTER site had at least one compelling “story” about what their site would look like in 50–100 yr. As the stories were prepared, themes emerged, and the stories were group into papers along five themes: state change, connectivity, resilience, time lags, and cascading …

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The Development Of A Procedure For The Pxrf Analysis Of Soil Cation Exchange Capacity In Collaboration With Colorado Farmers, Claire E. Wineman Jan 2021

The Development Of A Procedure For The Pxrf Analysis Of Soil Cation Exchange Capacity In Collaboration With Colorado Farmers, Claire E. Wineman

Senior Independent Study Theses

Discrepancies between farmers’ and scientists’ knowledge systems and experiences have long prevented the success and mutual beneficiality of collaborative research efforts between these two groups. The development of agricultural technologies, such as portable X-ray fluorescence (PXRF) for the analysis of soil cation exchange capacity in the field, creates a promising overlap point for farmers and scientists to cooperatively study issues within their sociocultural context and with access to institutional resources. In this study, the generation of an in-field PXRF method in collaboration with Colorado farmers helps to provide a prospective model for scientists and farmers looking to use collaborative research …

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Linking Landscape Attributes To Salmon And Decision-Making In The Southern Kenai Lowlands, Alaska, Usa, Coowe M. Walker, Dennis F. Whigham, I. Syverine Bentz, Jacob M. Argueta, Ryan S. King, Mark C. Rains, Charles A. Simenstad, Chris Guo, Steven J. Baird, Conrad J. Field Jan 2021

Linking Landscape Attributes To Salmon And Decision-Making In The Southern Kenai Lowlands, Alaska, Usa, Coowe M. Walker, Dennis F. Whigham, I. Syverine Bentz, Jacob M. Argueta, Ryan S. King, Mark C. Rains, Charles A. Simenstad, Chris Guo, Steven J. Baird, Conrad J. Field

School of Geosciences Faculty and Staff Publications

While Pacific salmon are economically and culturally important worldwide, Alaska, USA is one of the few remaining places on earth where sustainable management of salmon is possible, even in the face of wide-ranging threats, including overharvesting and the impacts of climate change. A continuing challenge that we face is to understand the ecological processes that result in sustainable salmon populations and report that science to stakeholders in a way that promotes decision-making to avoid the destruction of salmon populations that has occurred in most areas of the lower 48 states. To address this challenge, our studies in the southern Kenai …

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Large-Volume And Shallow Magma Intrusions In The Blackfoot Reservoir Volcanic Field (Idaho, Usa), M. S. Hastings, C. B. Connor, P. Wetmore, R. Malservisi, L. J. Connor, M. Rodgers, P. C. Femina Jan 2021

Large-Volume And Shallow Magma Intrusions In The Blackfoot Reservoir Volcanic Field (Idaho, Usa), M. S. Hastings, C. B. Connor, P. Wetmore, R. Malservisi, L. J. Connor, M. Rodgers, P. C. Femina

School of Geosciences Faculty and Staff Publications

he Blackfoot Reservoir volcanic field (BRVF), Idaho, USA, is a bimodal volcanic field that has hosted silicic eruptions during at least two episodes, as recently as 58 ka. Using newly collected ground and boat-based gravity data, two large negative anomalies (-16 mGal) are modeled as shallow (< 1  km) intrusions beneath a NE-trending alignment of BRVF rhyolite domes and tuff rings. Given the trade-off between density contrast and model volume, best-fit gravity inversion models yield a total intrusion volume of 50-120 km3; a density contrast of -400 kg m-3 results in two intrusions, each ~9 km x 4.5 km and about 0.5 km thick, with cumulative volume of 100 km3. A network of 340°-360° trending faults lies directly above and on the margins of the mapped gravity anomalies. Most of …

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The Potential For Remote Sensing Measurement Of Dissolved Organic Carbon As A Tool For Metal Risk Assessments, Mickey Nielsen Jan 2021

The Potential For Remote Sensing Measurement Of Dissolved Organic Carbon As A Tool For Metal Risk Assessments, Mickey Nielsen

Theses and Dissertations (Comprehensive)

The biotic ligand model (BLM) is a tool used to quantitatively evaluate how receiving water chemistry affects the bioavailability of metals. Sensitivity testing can be used to understand how the model outputs vary in response to systematic changes in water chemistry inputs. This will allow users of such models to understand how accurate their input parameters must be for a specified level of confidence in the output. Our focus was on dissolved organic carbon (DOC), which is often the most limiting data for application of BLM approaches to metals risk management. To potentially address DOC data limitations remote sensing can …

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The Role Of Symbiotic Algae In The Acclimatization Of Oculina Arbuscula To Ocean Acidification, Erin M. Arneson Jan 2021

The Role Of Symbiotic Algae In The Acclimatization Of Oculina Arbuscula To Ocean Acidification, Erin M. Arneson

College of Graduate Studies: Theses & Dissertations

Ocean acidification (OA) caused by CO2 emissions is projected to decrease seawater pH to 7.6 by 2100. Scleractinian corals are at risk because excess H+ in seawater binds to carbonate (CO32-), reducing its availability for CaCO3 skeletons. The energy demand for skeletal growth increases as pH decreases because corals must actively purge excess H+ from their seawater sourced calcifying fluid to maintain high calcification rates. In scleractinian corals it is hypothesized that photosynthesis by symbiotic algae is critical to meet this increased energy demand. To test this hypothesis, I conducted laboratory and field …

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Importance Of Low-Relief Nursery Habitat For Reef Fishes, Michael A. Dance, Ray R. Rooker, Richard Kline, Antonietta Quigg, Gregory R. Stunz, R. J. David Wells, Kirsten Lara, Jessica Lee, Bobbie Suarez Jan 2021

Importance Of Low-Relief Nursery Habitat For Reef Fishes, Michael A. Dance, Ray R. Rooker, Richard Kline, Antonietta Quigg, Gregory R. Stunz, R. J. David Wells, Kirsten Lara, Jessica Lee, Bobbie Suarez

School of Earth, Environmental, & Marine Sciences Faculty Publications

Coastal restoration projects to mitigate environmental impacts have increased global demand for sand resources. Unfortunately, these resources are often extracted from sand/shell banks on the inner continental shelf, resulting in significant alteration or loss of low-relief reefs in coastal oceans. Experimental reefs (oyster shell, limestone rubble, composite) were deployed in the western Gulf of Mexico to assess their potential value as nurseries for newly settled reef fishes. Occurrence, abundance, and species richness of juvenile fishes were significantly higher on all three types of low-relief reefs compared with unconsolidated sediment. Moreover, reefs served as nursery habitat for a range of reef …

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Founding Monsters Tales, Maggie Colangelo, Bernard Means Jan 2021

Founding Monsters Tales, Maggie Colangelo, Bernard Means

Founding Monsters

The creative team behind the Founding Monsters comic book—Maggie Colangelo and Dr. Bernard K. Means—bring you Founding Monsters Tales. Founding Monsters Tales features all-new art by Maggie and explores and expands on themes in Founding Monsters. Meet again Moses Williams, an enslaved servant of the Peale family who not only helped reconstruct the first mastodon skeleton, but was an unheralded artist in his own right. Find out whether mastodons were meat eaters, and how they differed from mammoths. Learn whether Thomas Jefferson was correct in his interpretation of what he called “the great claw.” Discover what Jefferson thought …

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