Digital Commons Network^™

Nutrient Restoration Of A Large, Impounded, Ultra-Oligotrophic Western River To Recover Declining Native Fishes, Ryan S. Hardy, Tyler J. Ross, Kevin N. Mcdonnell, Michael C. Quist, Charlie Holderman, Bryan S. Stevens

United States Geological Survey: Staff Publications

Declines in many fish populations in large, western rivers have been primarily attributed to the anthropogenic reduction of nutrient inputs and subsequent impacts to the food web. The largest known river fertilization program was implemented starting in 2005 on the Kootenai River in northern Idaho to restore resident fisheries. Annual electrofishing surveys were conducted at multiple sites in Idaho and Montana before and during nutrient addition to evaluate assemblage and population-level responses. Although few responses in fish assemblage structure were observed, the addition of liquid ammonium polyphosphate fertilizer (3 μg/L) to the Kootenai River increased fish abundance and biomass over …

Structural And Biological Analysis Of Faults In Basalts In Sheepshead Mountains, Oregon As An Earth Analogue To Mars, Allison Bohanon

Theses and Dissertations

Microbial life on Mars is not visible from orbit or by rover cameras, but the fracture networks and scarp morphologies associated with fractures they could live in are measurable. We conducted a field analogue study of 92 normal fault scarps in the Sheepshead Mountains, Oregon to examine the correlation between scarp morphology and vegetation growth in the Steens Basalt. While vegetation is not expected on Mars, the fracture networks that sustain vegetation offer the same micro-environment that would support and protect endoliths. Structural variables were measured in the field and infrared spectra of fault scarps were measured using a handheld …

Analysis Of Fossil Pollen From A Pleistocene Cypress Forest Preserved On The Northern Gulf Of Mexico Continental Shelf, Kathryn Joyce Garretson

Master's Theses

This study presents the findings of fossil pollen analysis performed on terrestrial sediments preserved on the northern Gulf of Mexico continental shelf (site hereafter known as the Underwater Forest or DF). This research aims to establish vegetation composition on a continental shelf glacial refuge and provide a better understanding of vegetation response to sea-level rise. Two cores (15DF1 and 15DF3B) located at different locations within the forest were recovered and analyzed. Pollen results from both cores were similar, with high percentages of Taxodium and Nyssa pollen in the lowermost sections reflecting an assemblage typical of contemporary baldcypress swamps. Pollen assemblages …

Using Geologic Principles And Data To Create A Symphony For Wind Ensemble, Thomas J. Davis

2022 Symposium

Geology and geologic processes have featured in many pieces of classical music such as Alan Hovhaness’ symphonic works after Mt. St. Helens and Glacier Peak but these pieces are impressionistic and only take general inspiration from the geology of their subjects. This paper describes the creation of Tectonics (2021) a piece which incorporates and describes many geologic principles and processes, such as mantle convection, through the musical form of cannon, the formation of fold and thrust belts whose cross sections are directly visually recreated in the score, and the physical dynamics of earthquake waves demonstrated through variations of pitch and …

Age And Water-Quality Characteristics Of Groundwater Discharge To The South Loup River, Nebraska, 2019, Christopher M. Hobza, John E. Solder

United States Geological Survey: Water Reports and Publications

Streams in the Loup River Basin are sensitive to groundwater withdrawals because of the close hydrologic connection between groundwater and surface water. The U.S. Geological Survey, in cooperation with the Upper Loup and Lower Loup Natural Resources Districts, and the Nebraska Environmental Trust, studied the age and water-quality characteristics of groundwater near the South Loup River to assess the possible effects of a multiyear drought on streamflow.

Groundwater sampled in wells screened in Quaternary-age deposits displayed a wide range of mean ages (27 to 2,100 years), fraction modern, and susceptibility index values. Groundwater with higher concentrations of chloride and higher …

Reconstructing The Ecological Relationships Of Late Cretaceous Antarctic Dinosaurs And How Functional Tooth Morphology Influenced These Relationships, Ian D. Broxson

2022 Symposium

The Sandwich Bluff Formation of the James Ross Basin of Antarctica has recently yielded a group of five late Cretaceous dinosaurs that lived contemporaneously with each other, a first for Antarctica. These five dinosaurs include fragmentary remains of two differently sized elasmarian ornithopods, a possible megaraptor, a hadrosaur, and a nodosaur. In this study we will construct a model of the ecological relationships of late Cretaceous Antarctica. Additionally, we will look at what specific factors allowed this group of four herbivores and a carnivore to coexist in a restricted locality and what niches were filled by each species. Methods to …

Ontogenetic Niche Shift As A Driver Of Community Structure And Diversity In Non-Avian Dinosaurs, Katlin M. Schroeder

Biology ETDs

As some of the most charismatic megafauna to ever walk the earth, the physiology, morphology, growth and evolution of non-avian theropods has been studied exhaustively, yet little is understood about their roles in ecosystems as juveniles. For carnivorous megatheropods, which exceed 1,000kg in mass yet hatched from eggs of limited size, the likelihood of utilizing different prey through ontogeny was high, simply by proxy of the immense difference in size between adults and juveniles. We found these ontogenetic niche shifts, evidenced by significantly different dental microwear in Tyrannosaurids, to have excluded dinosaurian mesocarnivores from Mesozoic communities. The few dinosaurian mesocarnivores …

The Current State Of Community Engagement In Urban Soil Pollution Science, Nicole Fernández-Viña, Yujuan Chen, Kirsten Schwarz

Agricultural and Environmental Sciences Faculty Research

Environmental burdens disproportionately impact the health of communities of color and low-income communities. Contemporary and legacy industry and land development may pollute soils with pesticides, petroleum products, and trace metals that can directly and indirectly impact the health of frontline communities. Past efforts to study environmental injustice have often excluded those most impacted, created distrust of researchers and other experts among frontline communities, and resulted in little to no structural change. Prevailing research methods value formal knowledge systems, while often dismissing the knowledge of those most harmed by environmental hazards. Community science has emerged as a process of doing science …

A Method For Phenotyping Roots Of Large Plants, Brian Rinehart, Hanna J. Poffenbarger, Daniel Lau, David H. Mcnear

Plant and Soil Sciences Faculty Publications

Linking root traits to plant functions can enable crop improvement for yield and ecosystem functions. However, plant breeding efforts targeting belowground traits are limited by appropriate phenotyping methods for large root systems. While advances have been made allowing for imaging large in situ root systems, many of these methods are inaccessible due to expensive technology requirements. The aim of this work was to develop a plant phenotyping platform and analysis method suitable for assessing root traits of large, intact root systems. With the use of a purpose-built imaging table and automated photo capture system, machine learning-based image segmentation, and off-the-shelf …

Tetracapsuloides Bryosalmonae Ecology In Southwest Montana, Paul Helfrich

Graduate Theses & Non-Theses

Tetracapsuloides bryosalmonae is a microscopic myxozoan parasite of freshwater bryozoans and salmonid fish. Infection by T. bryosalmonae under certain environmental conditions causes a deadly immune response in salmonid hosts known as proliferative kidney disease (PKD). Although T. bryosalmonae is present in rivers in western Montana, its distribution, as well as that of its bryozoan hosts, is poorly understood. Environmental chemistry, environmental DNA (eDNA), and bryozoan surveys were conducted at 10 study sites on the Big Hole River and Madison River to assess the presence of the parasite and bryozoans in these areas. T. bryosalmonae DNA was detectable across a wide …

A Social-Ecological-Technological Systems Framework For Urban Ecosystem Services, Timon Mcphearson, Elizabeth M. Cook, Marta Berbés-Blázquez, Chingwen Cheng, Nancy B. Grimm, Erik Andersson, Olga Barbosa, David G. Chandler, Heejun Chang, Mikhail V. Chester, Daniel L. Childers, Stephen R. Elser, Niki Frantzeskaki, Zbigniew Grabowski, Peter M. Groffman, Rebecca L. Hale, David M. Iwaniec, Nadja Kabisch, Christopher Kennedy, Samuel A. Markolf, A. Marissa Matsler, Lauren E. Mcphillips, Thaddeus R. Miller, Tischa A. Muñoz-Erickson, Emma Rosi, Tiffany G. Troxler

Advanced Science Research Center

As rates of urbanization and climatic change soar, decision-makers are increasingly challenged to provide innovative solutions that simultaneously address climate change impacts and risks and inclusively ensure quality of life for urban residents. Cities have turned to nature-based solutions to help address these challenges. Nature-based solutions, through the provision of ecosystem services, can yield numerous benefits for people and address multiple challenges simultaneously. Yet, efforts to mainstream nature-based solutions are impaired by the complexity of the interacting social, ecological, and technological dimensions of urban systems. This complexity must be understood and managed to ensure ecosystem-service provisioning is effective, equitable, and …

The Use Of Time-Lapse And Still Photographs To Document The Effects Of Seasonality On Dune Morphodynamic Evolution In Corolla, Nc., Briar Ownby-Connolly

Honors Theses

With climate change altering established seasonal and weather phenomena, understanding the physical behavior of barrier islands and the processes driving such physical changes, specifically within their dune zones, is crucial in promoting their resiliency. With ecosystem services provided by dunes to coastal economies and wildlife habitat, promoting dune conservation serves to advance the benefits of these systems, within a changing climate. Current findings by the Army Corps of Engineers Field Research Facility in Duck, NC, suggest the significance of local aeolian sediment transport in interplay with storm intensity in effecting dune stability, and that anthropogenic impacts, like the installment of …

Factors Influencing Tree Growth In A Bottomland Hardwood Along The Green River In Kentucky, Caleb Miller

Masters Theses & Specialist Projects

In bottomland hardwood forests, large fluctuations in moisture availability can lead to stress from both flooded and drought conditions. These forests can have a complex species composition with different water use and drought strategies. The bottomlands in which these species co-occur can have a complex spatial distribution of alluvial sediments due to the meandering and migration of river or stream channels, which may impact the hydrology, nutrient dynamics, and productivity. At Western Kentucky University's Green River Preserve, approximately 9 ha of bottomland hardwood forest were planted in 2006. Although these hardwoods have received equal amounts of sunlight, rainfall, and wind, …

Rodent Dental Microwear Texture Analysis As A Proxy For Fine-Scale Paleoenvironment Reconstruction, Jenny H. E. Burgman

Graduate Theses and Dissertations

Dental microwear texture analysis (DMTA) of fossil fauna has become a valuable tool for dietary inference and paleoenvironment reconstruction. Most of this work has utilized larger taxa with larger home ranges. These studies may result in broader-scale habitat inferences that could mask the details of complex mosaic habitats. Rodent DMTA offers an opportunity to work at finer spatial scales because most species have smaller home ranges. Rodents are also keystone species within their ecosystems, abundant, ubiquitous, and found in many fossil deposits. These attributes make them excellent proxies for environmental reconstructions. However, the application of DMTA to rodents remains relatively …

Halodash: The Deep And Shallow History Of Aquatic Life's Passages Between Marine And Freshwater Habitats, Eric T. Schultz, Lisa Park Boush

EEB Articles

This series of papers highlights research into how biological exchanges between salty and freshwater habitats have transformed the biosphere. Life in the ocean and in freshwaters have long been intertwined; multiple major branches of the tree of life originated in the oceans and then adapted to and diversified in freshwaters. Similar exchanges continue to this day, including some species that continually migrate between marine and fresh waters. The series addresses key themes of transitions, transformations, and current threats with a series of questions: When did major colonizations of fresh waters happen? What physiographic changes facilitated transitions? What organismal characteristics facilitate …

Using Thermal Units To Predict Biomass Accumulation And Total Nitrogen Uptake For Cover Crops In Arkansas, Mila Victório Pessotto

Graduate Theses and Dissertations

Including cover crops in agricultural production systems is an important management practice. Cover cropping can improve soil health, increase plant-available nitrogen (N), provide surface residue to prevent erosional soil loss, increase water infiltration, and increase weed suppression. Cover crops growth can be predicted using thermal days or growing degree days [GDD] similar to commodity crops such as corn (Zea mays L.) or rice (Oryza sativa). Growing degree day calculations are a well-known tool to predict crop growth stage or development stage and can be adapted for use in any plant species, including cover crops. Identifying and developing the relationship between …

Feasibility Assessment On Use Of Proximal Geophysical Sensors To Support Precision Management, Sophia M. Becker

School of Natural Resources: Dissertations, Theses, and Student Research

Soil property maps provide information for field management activities such as irrigation, fertilization, and seeding. Many on-the-go proximal geophysical sensors have been developed in recent decades that can help map agricultural fields without dense soil sampling. To utilize these technologies most profitably in precision management, scientists and precision agriculture dealers must better understand sensors’ performances in given field conditions and the economic value of different proximal soil sensing methods. Chapter two reports the study that was conducted at three sites in North Dakota, United States to strengthen understanding of the usefulness of different proximal geophysical data types in agricultural contexts …

Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano

All Theses

Toxoplasma gondii is a pathogenic microorganism that is currently a threat to public health. Understanding the fate and transport of T. gondii through the soil and groundwater is vital in determining the risk it poses to water resources and human health. The physico-chemical interactions between the groundwater and the bio colloid within an aquifer will dictate its mobility and its ability to infect humans. This research examines how various naturally occurring groundwater chemistries containing organic compounds and monovalent and divalent salt solutions will alter the fate and transport of T. gondii. Solutions containing various concentrations of humic acid, fulvic …

Monitoring Sars-Cov-2 Risk With Co2. The Importance Of Ventilation, Masks, And Vaccinations., Preston Betz

Earth Sciences Theses and Dissertations

To assess airborne pathogen infection risk, concentrations of interior carbon dioxide and changes in relative humidity serve as proxies for human respiration products. Yanes and Yapp, 2010, demonstrated that interior air carbon dioxide concentrations and ¹³C/¹²C ratios display a two-component mixing relationship between respiration carbon dioxide which is highly concentrated (>100x atmospheric) in respiration air CO₂ at >40,000 ppm compared with ambient air (~410 ppm). In the absence of combustion carbon dioxide, the concentration of carbon dioxide, in an interior space, depends on the rate of respiration CO₂ addition relative to the amount of …

Dental Morphology In A Juvenile Mammal From The Late Cretaceous Of South America: Tooth Eruption And Development., Kayla E Newton

Electronic Theses and Dissertations

Meridiolestids are a diverse and distinct clade of Cretaceous–Miocene South American dryolestoid mammals ranging in size from small shrew-sized insectivores to large dog- sized omnivores. Cronopio dentiacutus from the Cenomanian La Buitrera locality, Rio Negro Province, Argentina (Candeleros Fm.) is the oldest and best known of them, represented by skull material and associated jaws. A juvenile skull as attributed to Cronopio dentiacutus, based on tooth size and morphology, was collected from the type locality. The specimen includes the skull and both articulated lower jaws. The fossil is poorly ossified and partially flattened; CT scanning reveals most of the dentition …

Community Structure Analysis Of Mammals Found At The Gray Fossil Site, Tn, Sarah Clark

Electronic Theses and Dissertations

The early Pliocene Gray Fossil Site (GFS) is a biodiverse site with a unique faunal assemblage that represents one of few sites of its age in eastern North America. A community structure analysis of the mammals at GFS was done to characterize species and better understand the paleoenvironment. Data and was gathered from twenty modern communities and five late Neogene sites to compare with GFS. Species from these 26 sites were categorized by body size, locomotor mode, cheek tooth crown height, and diet to characterize niches occupied. Descriptive statistics contrasted proportions of species within categories across communities. Discriminant function analyses …

Understanding Biogeochemical And Physical Controls On Methane Air-Sea Exchange Fluxes In The Pacific Ocean, Sarah Raney

Master's Theses

Methane and trace element samples were collected on GEOTRACES GP15 Pacific Meridional Transect (PMT) cruise conducted between the Aleutian Islands (57 °N) and Tahiti (20 °S) from September to November 2018. Uncertainty in methane air-sea exchange fluxes was determined using a propagation of errors approach. Fluxes ranged from -0.88 to 4.9 µmol CH₄ m^-2 d^-1. Average CH₄ flux along the Alaskan margin was 2.2 ± 2.9 µmol CH₄ m^-2 d^-1. Methane fluxes decreased moving southward and increased to their open ocean maximum around 20 °N before declining in equatorial waters. Near …

Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker

All Dissertations

Uranium (U) released from the M-Area at the Department of Energy Savannah River Site into Tims Branch, a seasonal wetland and braided stream system, is estimated to be 43,500 kg between 1965 and 1984. The motivation for this work is the uranium’s persistence in the wetland for decades, where it is estimated that 80% of the U currently remains in the Tims Branch wetland. U has begun to incorporate into wetland iron (Fe) and carbon cycles, associating with local Fe mineralogy and deposits of rich wetland organic matter (OM). The objective of this work is to characterize the chemical phases …

Characterization Of Water Flow And Solute Transport Driven By Preferential Flow In Soil Vadose Zone, Abdullah Al Mamun

All Dissertations

The vadose zone acts as a buffer zone between the ground surface and the aquifers underneath and controls the transmission of infiltrating water and contaminants, for example, pesticides and chemical spills. Therefore, understanding the flow and transport processes that dominate the vadose zone is important. Macropores are ubiquitous and particularly found in abundance in the vadose zone. These macropores facilitate preferential flow, through which water travels rapidly deep into the soil, bypassing most of the porous matrix. Preferential flow and transport have environmental significance as their processes impact hydrology, ecology, agriculture, subsurface contamination, and waste management sectors. Thus, the overall …

Interdisciplinary Studies Masters Degree In Anthropological & Science Based Education, Robert Porter

Electronic Theses, Projects, and Dissertations

The goal of this project is to develop anthropological and science-based curricula that will emphasize a place-based approach while actively engaging students in their education. I developed two curricula for elementary aged students in San Bernardino. The first curriculum was based anthropologically on the local history of indigenous groups and early San Bernardino history. The second was based on paleontology here in California with a focus on dinosaurs and fossils.

To improve and validate the curricula I sent the examples to educational experts and had them critique the lessons and information provided. Then I used their input to improve the …

A Socio-Ecological Model To Assess Tuberculosis In Migrant Farmworkers In The Us-Mexico Border Region, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

The migrant and seasonal farmworker toiling in the fields and orchards of the United States of America surmounts innumerable problems daily. Some of these problems pertain to the overall health of the farmworker in addition to the various occupational hazards that he or she faces. This research paper focuses on Tuberculosis infection—both latent and active—in the migrant farmworkers in the United States with a special focus on the US-Mexico border. Using the Socio-Ecological Model as a theoretical framework, the TB health issues faced by this group are studied. The various determinants of health at every level of the Socio-Ecological Model …

Water Quality Assessment Of Karst Spring Water As A Private Water Supply Source In Northeast Tennessee, Lukman Fashina

Electronic Theses and Dissertations

Karst springs are an essential source of private water supply for about 10% of households in Tennessee. However, these springs, which can be easily polluted, are unregulated. This study, therefore, assesses water quality spatial patterns and water quality rating of roadside springs in northeast Tennessee.

Karst spring water samples collected from 50 springs were assessed using EPA Standard methods for pathogens, nutrients, radon, and physicochemical parameters. Springs generally met federal and state standards for physicochemical parameters, 90% of samples contained E. coli, and all samples contained fecal coliform. High E. coli was spatially clustered causing a fecal contamination hot …

Air, Land, And Water Variables Associated With The First Appearance And Current Spatial Distribution Of Toxic Prymnesium Parvum Blooms In Reservoirs Of The Southern Great Plains, Usa, Shisbeth Tábora-Sarmiento, Reynaldo Patiño, Carlos Portillo-Quintero, Cade Coldren

United States Geological Survey: Staff Publications

This study examined the association of air, land, and water variables with the first historical occurrence and current distribution of toxic Prymnesium parvum blooms in reservoirs of the Brazos River and Colorado River, Texas (USA). One impacted and one reference reservoir were selected per basin. Land cover and use variables were estimated for the whole watershed (WW) and a 0.5-km zone on either side of streams (near field, NF). Variables were expressed in annual values. Principal component and trend analyses were used to determine (1) differences in environmental conditions before and after the 2001 onset of toxic blooms in impacted …

Red Harvester Ant (Pogonomyrmex Barbatus F. Smith; Hymenoptera: Formicidae) Preference For Cover Crop Seeds In South Texas, Lilly Victoria Elliott-Vidaurri, Daniella Rivera, Adrian Noval, Robin A. Choudhury, Hannah J. Penn

School of Earth, Environmental, & Marine Sciences Faculty Publications

Harvester ants often selectively forage seeds, causing these ants to be viewed as pests in agricultural areas where they may forage on crop seeds. While little research has been done on harvester ant preferences for cover crop seeds, grower observations in the Lower Rio Grande Valley (LRGV) suggest that ants may remove these seeds before germination. We examined red harvester ant (Pogonomyrmex barbatus F. Smith) preferences for cover crop seeds (fescue, oat, sunn hemp, radish, vetch, and wheatgrass) and the effects of a commonly used bacterial seed inoculant. We evaluated relative preferences using seed depots presented to colonies with no …

Unveiling The Nature Of A Miniature World: A Horizon Scan Of Fundamental Questions In Bryology, Jairo Patiño, Irene Bisang, Bernard Goffinet, Lars Hedenäs, Stuart Mcdaniel, Silvia Pressel, Michael Stech, Claudine Ah-Peng, Sarah Eppley, Multiple Additional Authors

Center for Life in Extreme Environments Publications

Introduction: Half a century since the creation of the International Association of Bryologists, we carried out a review to identify outstanding challenges and future perspectives in bryology. Specifically, we have identified 50 fundamental questions that are critical in advancing the discipline.

Methods: We have adapted a deep-rooted methodology of horizon scanning to identify key research foci. An initial pool of 258 questions was prepared by a multidisciplinary and international working group of 32 bryologists. A series of online surveys completed by a broader community of researchers in bryology, followed by quality-control steps implemented by the working group, were …