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Community Structure Analysis Of Turtles With Application To The Early Pliocene Gray Fossil Site, Julian Conley

Electronic Theses and Dissertations

Turtles are important components of ecosystems around the world, with diverse ecological niches and adaptations. However, there are few detailed studies of how turtle community structure reflects local environments. This project applied techniques of community structure analysis to sites across the United States to infer past ecosystem and environmental conditions of the early Pliocene Gray Fossil Site (GFS) in northeastern Tennessee based on the ancient turtle community. Results indicate extant turtle community structure closely reflects environmental conditions, and that ancient turtle communities can be used to infer climate and habitat conditions of past ecosystems. Application to the GFS turtle community …

Analysis Of Soil Change Across Nebraska, Trinity Baker

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

The world’s population is growing and an increasing populace requires more resources. These requirements place increasing pressure on the environment and the soil. Soils serve many important functions throughout the world. These functions range from offering a media for food production, providing a sink for organic carbon, nutrient cycling, and improving water quality. It is important to focus on the human impact on soils and their change over time.

For my research I examined how soils across Nebraska have changed over a time period of roughly 65 years. I sampled and analyzed 39 pedons from four Major Land Resource Areas …

Petrochronology And Statistical Analysis To Integrate Different Types Of Data To Solve Complex Earth Systems Problems, Claire Ostwald Harrigan

Boise State University Theses and Dissertations

Complex Earth systems problems, like reconstructing orogens and calibrating the geologic time scale, require investigations that link time to geologic processes. To use time as a means of organizing geologic evidence, geochronometric dates must be contextualized by integrating with different data types. This is the work of petrochronology—linking mineral ages to geochemical, textural, or other geologic information. The U-Pb isotopic system as preserved in the minerals zircon (ZrSiO₄) and titanite (CaTiSiO₅) can be used in a petrochronological context to date geologic events including the age of granitoid pluton emplacement, the age of rock fabric formation in …

From River Channel To Cloud Tops: Evaluation And Applications Of Regional Climate Models In Mountain Watersheds, William J. Rudisill

Boise State University Theses and Dissertations

Mountain ranges are vital ”water towers” of the world and are uniquely threatened by anthropogenic climate change. At the same time, the paucity of observing networks limits our understanding of hydrometeorological processes in water-resource critical regions, including the Western United States. In the past decade, non-hydrostatic, convection permitting ( 1-4km horizontal resolution) regional climate models (RCMs) have emerged as a promising tool for both reconstructing regional scale mountain hydroclimates, and for forecasting the impacts of climate perturbations on watersheds and water-resources. Still, challenges remain. To-date, computational and data storage limitations have generally precluded many RCM studies to a handful of …

A Cross-Scale Nexus: Microbial Functional Genes In Tandem With Molecular-Level Nitrogen Fluxes And Implications For Field-Scale Biogeochemical Processes, Srusti Maddala

Graduate Theses and Dissertations

Nitrogen (N) biogeochemical cycling entails close networking between soil nutrients, plant species and resulting microbial communities, and abiotic factors such as temperature, moisture, and pH. To better understand transformations of N in soil microsites, which are known to be rich in N-cycling behavior, the microdialysis technique was employed to generate in situ data on temporal alterations of N during wetting-drying conditions in both the field and laboratory. The objectives were to 1) determine the lifespan of the microdialysis technique in field conditions, 2) evaluate the ability of the method to yield N fluxes that would be differential between the two …

College Of Natural Sciences Newsletter, July & August 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 5

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Resources for Student Success
Page 4 Welcome to New Faculty & Staff
Page 5 Summer Activities in CNS
Page 9 Celebrating the lives of those who touched the College
Page 10 Media Coverage of CNS
Page 12 Open PRAIRIE Data
Page 13 Snaps from he start of the semester
Page 14 Science as Art Competition

Examining The Expression Patterns Of Desulfotalea Psychrophila Dsrab Operon And Pit At Subfreezing Temperatures And Different Concentrations Of Sulfate Salts As A Model For Mars And Icy Worlds Survival And Colonization, Sergio Luis Mosquera Mora

Graduate Theses and Dissertations

Since ancient times, Humanity has been fascinated with the idea of what lies beyond the borders of our planet. Fortunately, the combined efforts of many nations have made it possible to send unmanned spacecraft to orbit planets located close to Earth. These missions have the principal goal to collect data that could help us understand the basic environmental conditions that persist on those planets, or for evidence of past or present life. Equally important, landers and rovers have been successfully deployed to start the in-situ exploration of many planets of the Solar System. Among them, Mars has been extensively studied …

Growth And Reproduction In Gulf Of Mexico Black Corals (Antipatharians) In Field And Laboratory Studies, Victoria E. Salinas

Theses and Dissertations

Black corals provide an important ecosystem of marine life and are found throughout all the oceans of the world at depths between 2 and 8,600 m. However, little is understood about their life history and the factors that control the distribution of black corals, particularly in the Gulf of Mexico (GoM). Given the impacts of the Deepwater Horizon oil spill on soft corals (e.g., black corals and octocorals) in the GoM, studies of their growth and reproductive biology in both natural and aquaculture environments are crucial for restoration efforts. The objectives of this study were to examine reproductive processes, compare …

Network Analysis Of Scientific Research In The Gulf Of Mexico, Juliet S. Vallejo

Theses and Dissertations

The Gulf of Mexico ecosystem represents a significant management challenge in its 3,423-mile coastline and transnational regulatory setting, along five states from the United States, six states from Mexico, and Cuba which borders the southeastern quadrant. Providing various resources to the regional economies, the continued success of these resources depends on the collaboration among transnational participants in bringing together complementary skills and multidisciplinary approaches to producing, circulating, and utilizing scientific knowledge. Using bibliometric analysis of Gulf of Mexico-related published research over 18 years from 2000 to 2018 allows for identifying organizations, their connections, and trends in the production of scientific …

The Paleoecology Of High-Elevation Bison In The Greater Yellowstone Ecosystem And Implications For Modern Bison Conservation, Darian Bouvier

Electronic Theses and Dissertations

The national mammal of the United States, the American Bison (Bison bison) was once nearly extinct. Populations have recovered to the degree that thousands roam the Great Plains today. Due to their large numbers and body size, this species has an oversized impact on the ecological communities where it lives and is considered a keystone herbivore in modern North American grasslands. This study explores the detailed, seasonally resolved, paleoecology of seven bison from the Greater Yellowstone Ecosystem during the Late Holocene through stable isotope analyses and species niche modeling. Isotopic analyses of δ¹³C, δ¹⁵N, …

Investigation Of Dead Ocean Quahogs (Arctica Islandica) Shells On The Mid-Atlantic Bight Continental Shelf, Alyssa Leclaire

Master's Theses

Ocean quahogs, Arctica islandica, are a long-lived, widely dispersed, biomass dominate in the Mid-Atlantic; therefore, quahog shells are valuable resources for studying climate change over time. Recently, dead ocean quahog shells were discovered south and inshore of the present biogeographic range of this animal. The presence of ocean quahog shells outside the current range is presumably a consequence of past regressions and transgressions of the Cold Pool, the bottom-trapped, cool body of water that allows boreal animals to live at lower latitudes. Dead ocean quahog shells were collected offshore of the DelMarVa Peninsula then radiocarbon-dated, evaluated for taphonomic condition, …

Faunal Comparison And Analysis Of The Blufftown Formation-Cusseta Sand Contact At Hannahatchee Creek, Georgia, Seth Fradella

Honors Theses

The origin of fossil material in the highly fossiliferous bed above the Upper Cretaceous (Campanian) Blufftown Formation-Cusseta Sand contact at Hannahatchee Creek, Georgia, has long been a subject of scientific curiosity; however, no research has yet been conducted to specifically investigate discrepancies between the fossil assemblages of the upper Blufftown Formation and the basal Cusseta Sand, which overlies it unconformably. In the most recent published hypothesis, Case and Schwimmer (1988) propose that the basal Cusseta Sand contains a mixture of original fauna as well as material reworked and redeposited from the underlying Blufftown Formation, resulting in a lag deposit above …

Urban Soil Chemical And Nutrient Management Issues Facing Emerging Small Grower Enterprises In Utah, Frank E. Oliver

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Knowledge of both soil quality and contamination has become increasingly important with the growth of urban agriculture in Utah and the United States as whole. Land is also a common limiting factor in urban agriculture, so it is important to maximize yield and net returns. In order to meet these demands, three studies were conducted across key urban agriculture sites along the Wasatch Front: 1) an urban soil survey to assess soil contamination, 2) an urban soil survey to evaluate macronutrient and salinity levels, and 3) a nitrogen fertilizer management trial for dahlia (Dahlia pinnata), a cut flower …

Holocene Chronostratigraphy Of Dune Fields In Southern Utah: Geomorphic Record Of Past Aridity In The Central Colorado Plateau, Harriet S. Cornachione

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The southwestern United States is characterized by dry climate, and droughts are common. The region is currently in an extreme drought that began in 2000 CE and has lasted longer than any previous drought in at least 500 years. Models predict greater future climate extremes under human-caused climate change. Understanding of the natural range of climate variability is important to put these changes in context. Sedimentary archives of past sand dune activity can help extend the available instrumental observations (last century) and tree-ring records (last millennium).

Sand dunes are landforms that are sensitive to aridity and decreased vegetation cover. They …

A Comparison Of Relict And Active Terrestrial Patterned Ground As An Analog For Mars, John Paul Knightly Jr.

Graduate Theses and Dissertations

Patterned ground is a ubiquitous landform in periglacial regions of Earth and is also present across the mid to high latitudes of Mars. The association of terrestrial patterned ground to the presence of subsurface water ice in the form of permafrost that develops a seasonal ‘wet’ active layer during the summer thaw prompted further investigation of patterned ground on Mars. The Phoenix spacecraft was sent to the surface of the north polar plains of Mars to investigate an area of patterned ground where water ice was predicted to occur. The confirmation of subsurface water ice at the Phoenix landing site …

Optimization Techniques For Soil Organic Carbon Prediction Using Mid-Infrared Spectroscopy, Minerva J. Dorantes

Graduate Theses and Dissertations

Resource-efficient techniques for accurate soil carbon estimation are necessary to satisfy the increasing demand for spatiotemporal data. In the last thirty years, mid-infrared (MIR) soil spectroscopy has developed as an accurate, rapid, cost-effective, and non-destructive technique for soil organic carbon (SOC) analysis. In soil spectroscopy, a calibration model relates spectral data to a corresponding measured soil property and is subsequently used to predict this value from new spectral data. Various optimization techniques have been used to improve the statistical performance of calibrations; however, there is little consensus on the conditions that make these techniques effective. The objectives of this research …

Assessment Of Nitrogen-Based Fertilizer Transport And Microbial Activities In Sandy Soil Profiles In South Texas, Gladys De La Rosa

Theses and Dissertations

Conventional farming is a common practice in Lower Rio Grande Valley (LRGV) and the application of nitrogen fertilizer is essential for plant growth and support. However, managing the rate of nitrogen that is applied can benefit farmers financially and reduce nitrate leaching that can have an adverse effect on the local environment and aquatic systems, e.g., rivers and estuaries. Sandy soils are more vulnerable to water infiltration due to the large proportion of macropores. This study aims to (i) assess how nitrate from a variety of fertilizers (i.e., synthetic and organic) distributes on the top 60 cm layer of a …

Defining The Current Distribution Of The Imperiled Black-Spotted Newt Across South Texas, Usa, Padraic S. Robinson, Drew R. Davis, Sean M. Collins, Richard Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Black-spotted Newt (Notophthalmus meridionalis) is a chronically understudied salamander species, with many aspects of its natural history, ecology, and distribution poorly known. Previous studies using traditional methodologies have had limited success documenting N. meridionalis on the landscape, detecting individuals at 6% (7 of 114) and 1% (2 of 221) of sites surveyed. A novel environmental DNA (eDNA) assay was designed and implemented with the goals of assessing the current distribution of N. meridionalis across south Texas, USA, and better understanding the conditions for positive eDNA detections. We conducted eDNA sampling and traditional surveys at 80 sites throughout …

Latitudinal Variance In The Drivers And Pacing Of Warmth During Mid-Pleistocene Mis 31 In The Antarctic Zone Of The Southern Ocean, Jonathan P. Warnock, Brendan T. Reilly, Maureen E. Raymo, Michael E. Weber, Victoria Peck, Trevor Williams, Linda Armbrecht, Ian Bailey, Stefanie Brachfeld, Zhiheng Du, Gerson Fauth, Marga M. García, Anna Glüder, Michelle Guitard, Marcus Gutjahr, Sidney Hemming, Iván Hernández-Almeida, Freida S. Hoem, Ji Hwan Hwang, Mutsumi Iizuka, Yuji Kato, Bridget Lee, Yasmina M. Martos, Suzanne O’Connell, Lara F. Pérez, Thomas A. Ronge, Osamu Seki, Lisa Tauxe, Shubham Tripathi, Xufeng Zheng, Joseph Stoner, Reed P. Scherer

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Early Pleistocene Marine Isotope Stage (MIS)-31 (1.081–1.062 Ma) is a unique interval of extreme global warming, including evidence of a West Antarctic Ice Sheet (WAIS) collapse. Here we present a new 1,000-year resolution, spanning 1.110–1.030 Ma, diatom-based reconstruction of primary productivity, relative sea surface temperature changes, sea-ice proximity/open ocean conditions and diatom species absolute abundances during MIS-31, from the Scotia Sea (59°S) using deep-sea sediments collected during International Ocean Discovery Program (IODP) Expedition 382. The lower Jaramillo magnetic reversal (base of C1r.1n, 1.071 Ma) provides a robust and independent time-stratigraphic marker to correlate records from other drill cores in the …

Geoenvironmental Implications On Food Sovereignty - Meskwaki Settlement, Tama County, Iowa, Lindsey Hubbell, Chad Heinzel Ph.D., Christina Blackcloud, Luke Kapayou, Avis Bear-Bass

Summer Undergraduate Research Program (SURP) Symposium

Native American culture demonstrates a spiritual relationship to food, land, and Earth. As opposed to European traditions valuing private property and exploiting the Earth for profit, Native American tradition believes the Earth is owned by no one; food and nourishment from it are a gift for all to take only as needed. The Meskwaki Nation originated around the Great Lakes but was removed to Tama County, Iowa. It is derived from the words “Meskwa” meaning “red” and “aki” meaning “Earth”. This Red Earth nation has initiated a Food Sovereignty program to pass along traditional growing and food preparation practices to …

The Diatom Dark Ages: Identification Of Mid-Cretaceous Arctic Platform Diatoms From The Basal Transgression Of The Kanguk Formation, Devon Island, Nunavut, Canada, Megan Heins

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

The lower part of the mid-Cretaceous Kanguk Formation (Lower Turonian interval) contains an important paleontological record crucial to the characterization of a poorly known interval of fossil marine diatoms history. Kanguk Formation mudstones are exposed in a ~200 m-thick section on Devon Island, Nunavut, Canadian High Arctic. Diatoms at this location are well-preserved due to shallow burial on this Arctic Platform site. The rock sequence was protected from glacial erosion that removed much of the Cretaceous record by being down-faulted in a linear graben. Study of these well-preserved fossil diatoms allows for a documentation of the assemblage, identification of potentially …

Coupling Dendrochronology And Remote Sensing Techniques To Assess The Biophysical Traits Of Juniperus Virginiana And Pinus Ponderosa Within Grassland Communities In The Semi-Arid Grasslands Of The Nebraska Sandhills, Reece Allen

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

Woody species encroachment is occurring within the sandhills region in Nebraska, primarily driven by Juniperus virginiana and Pinus ponderosa, altering ecosystems and the services they provide. Effective, low cost, and cross-scale monitoring of woody species growth and performance is necessary for integrated grassland and forest management in the face of climate variability and change. In this study, we sought to establish a relationship between remote sensing-derived vegetation indices (VIs) and dendrochronological (raw and standardized tree ring width) measurements to assess the performance of encroaching woody J. virginiana and P. ponderosa located within the Nebraska National Forest in the sandhills. …

Spatial Stream Modeling Of Louisiana Waterthrush (Parkesia Motacilla) Foraging Substrate And Aquatic Prey In A Watershed Undergoing Shale Gas Development, Mack W. Frantz, Petra B. Wood, Steven C. Latta

United States Geological Survey: Staff Publications

We demonstrate the use of spatial stream network models (SSNMs) to explore relationships between a semiaquatic bioindicator songbird, Louisiana Waterthrush (Parkesia motacilla), and stream monitoring and benthic macroinvertebrate data in an area undergoing shale gas development. SSNMs allowed us to account for spatial autocorrelation inherent to these environmental data types and stream properties that traditional modeling approaches cannot capture to elucidate factors that affect waterthrush foraging locations. We monitored waterthrush along 58.1 km of 1st- and 2nd-order headwater stream tributaries (n = 14) in northwestern West Virginia over a two year period (2013–2014), sampled benthic macroinvertebrates in waterthrush …

Ecological Restoration Strategies For Coal Mines In China Based On Vegetation Zones And Ecological Sensitivity, Zhou Hongxuan, Wang Zhaoqing, Pu Hongtong, Tao Guixin, Sun Jing

Coal Geology & Exploration

Coal is the main source of energy in China and the most important driver of our development for a long time. It is predicted that coal is going to be the main energy source for our social and economic development in the future. However, the long-term coal mining activities in China have caused serious damage to the ecological environment and comprehensive ecological restoration is urgently needed. At present, most coal mine ecological restoration is limited within a small scale in China, such as one or several mine areas, lacking of ecological restoration planning at the national spatial level, and corresponding …

Hybrid Conferences: Opportunities, Challenges And Ways Forward, Eleonora Puccinelli, Daniela Zeppilli, Paris V. Stefanoudis, Annaig Wittische-Helou, Marjorie Kermorgant, Sandra Fuchs, Lenaick Menot, Erin E. Easton, Alexandra A-T. Weber

School of Earth, Environmental, & Marine Sciences Faculty Publications

Hybrid conferences are in-person events that have an online component. This type of meeting format was rare before the COVID-19 pandemic, but started to become more common recently given the asynchronous global progression of the pandemic, the uneven access to vaccines and different travel regulations among countries that led to a large proportion of participants being unable to attend conferences in person. Here we report the organization of a middle-sized (581 participants: 159 onsite, 422 online) international hybrid conference that took place in France in September 2021. We highlight particular organizational challenges inherent to this relatively new type of meeting …

Iron And Magnesium Impregnation Of Avocado Seed Biochar For Aqueous Phosphate Removal, James Jihoon Kang, Jason Parsons, Sampath Gunukula, Dat T. Tran

School of Earth, Environmental, & Marine Sciences Faculty Publications

There has been increasing interest in using biochar for nutrient removal from water, and its application for anionic nutrient removal such as in phosphate (PO₄³⁻) necessitates surface modifications of raw biochar. This study produced avocado seed biochar (AB), impregnated Fe- or Mg-(hydr)oxide onto biochar (post-pyrolysis), and tested their performance for aqueous phosphate removal. The Fe- or Mg-loaded biochar was prepared in either high (1:8 of biochar to metal salt in terms of mass ratio) or low (1:2) loading rates via the co-precipitation method. A total of 5 biochar materials (unmodified AB, AB + High Fe, AB …

Effect Of Ultraviolet Light Treatment On Microbiological Safety And Quality Of Fresh Produce: An Overview, Veerachandra K. Yemmireddy, Achyut Adhikari, Juan Moreira

School of Earth, Environmental, & Marine Sciences Faculty Publications

Fresh and fresh-cut fruits and vegetables have been associated in several foodborne illness outbreaks. Although investigations from those outbreaks reported that the contamination with pathogenic microorganisms may occur at any point in the farm to fork continuum, effective control strategies are still being widely investigated. In that direction, the concept of hurdle technology involving a sequence of different interventions have been widely explored. Among those interventions, ultraviolet (UV) light alone or in combination with other treatments such as use of organic acids or sanitizer solutions, has found to be a promising approach to maintain the microbiological safety and quality of …

Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot

LSU Master's Theses

Coastal wetlands provide an abundance of ecosystem services that benefit society, such as essential habitat for commercial species, storm protection, nutrient cycling, and carbon storage. Louisiana faces rapid rates of relative sea level rise (natural subsidence and eustatic sea levels) that threaten wetland survival, which are amplified by a reduction of riverine sediment input. An important determining factor of marsh survival is the formation of wetland platform elevation, known as vertical accretion, which is determined by several processes including sediment deposition & erosion, below ground biomass (BGB) productivity, decomposition of organic matter, shallow & deep subsidence, and soil compaction. Feldspar …

Synchronous Retreat Of Southeast Greenland's Peripheral Glaciers, Julia Liu, Ellyn Enderlin, Hans-Peter Marshall, Andre Khalil

Geosciences Faculty Publications and Presentations

Recently, scientific attention has focused on estimating Greenland's dynamic mass loss through changes to flow speeds, thickness, and length on its marine outlet glaciers. For the ice sheet outlet glaciers, dynamic mass loss has been found to be highly sensitive to changes in climate and individual glacier geometry. For the ice-sheet-independent marine glaciers around Greenland's periphery, dynamic mass loss is presently overlooked. Here, we apply an open-source, automated method of measuring glacier length changes using satellite imagery, to produce highly detailed records of length changes for 135 peripheral marine glaciers in southeast Greenland. We find evidence for anomalous retreat across …

Functional Morphology And Taphonomy Of Ordovician–Silurian Diploporan Echinoderms, Stephen Ashley Hill

USF Tampa Graduate Theses and Dissertations

Diploporan echinoderms were one of the most speciose groups of stemmed echinoderms during the Ordovician. Despite this widespread abundance, the fossil record of diploporan fauna consists primarily of incomplete specimens, with complete specimens being rare. While the theca, or body, is more commonly preserved, the feeding appendages and the attachment structures (i.e. stems or holdfasts) are seldomly preserved. Insight into these features is highly valuable to the understanding the paleoecology, like the feeding and respiratory strategies, of these enigmatic creatures.

One group of diploporan echinoderms which does have an extensive fossil record, is the Holocystites Fauna, primarily known from the …