Digital Commons Network^™

Nanoscale Studies Of Magnesium Carbonate Precipitation At Ambient Conditions, Ian Shortt

Material Science and Engineering Dissertations - Archive

Currently approximately 8% of global greenhouse gas emissions can be attributed to the construction industry; of these emissions, a little over half of these emissions are due to the production of traditional calcium-based cements. Magnesium carbonate cements present a promising alternative to traditional calcium-based cements, both in terms of emission reductions and in terms of strength. The primary drawback to magnesium carbonate cements is that ambient curing is not yet viable. The objective of this dissertation is to therefore develop greater understanding of the precipitation pathways undertaken by hydrated magnesium carbonates under near-ambient conditions. In the first section of this …

Critical Convergence: Mapping The Boundaries Of How Faculty Interrogate Whiteness In The Geoscience Educational Landscape, James E. Hobbs

Educational Leadership & Policy Studies Dissertations - Archive

This study examined the role of faculty members in interrogating whiteness within geoscience education. The dominant reliance on whiteness as the primary way of knowing in geoscience education has long perpetuated a singular perspective that serves as a mechanism for reinforcing existing power structures rooted in white supremacy. Drawing on tenets from Critical whiteness Studies, Curriculum Theory, and Transformative Learning Theory, this research investigated U.S. higher education faculty members' strategies and challenges in disrupting whiteness within the geoscience curriculum.

Through critical qualitative narrative inquiry, data were collected through semi-structured interviews with geoscience faculty members across multiple institutions across the United …

Plant Water Uptake Strategies In An Urban Green Landscape, Erica G. Almance

Earth & Environmental Sciences Theses - Archive

Urban green landscapes have been widely recognized for potentially reducing surface water pollution and flood impacts. However, the understanding of the role that plants play in partitioning the urban water cycle is still limited. We present a study in the Fort Worth Botanic Garden to understand water uptake strategies from three common urban tree species (Elderberry, Sambucus canadensis; Cherry laurel, Prunus caroliniana; and Boxelder maple, Acer negundo) from February 2023 through January 2024. Stem (N=110) isotope ratios (δ18O and δ2H) are compared to multiple endmembers, including precipitation (N=509), throughfall (N=37), and soil water (N=135) at different depths (0- 38 cm). …

A Field-Based Study Of Dust Emissivity In The Northern Chihuahuan Desert, U.S.: Testing The Preferential Dust Source Scheme, Gwenn L Harsha

Dissertations and Theses

We characterized spatiotemporal dust emissivity in the Northern Chihuahuan Desert (New Mexico, Texas, and Arizona, U.S.) using the Portable In-Situ Wind Erosion Lab (PI-SWERL) and measurements of soil crust strength, soil texture and soil moisture. Field-based measurements of emissivity were compared to the results of the Preferential Dust Source (PDS) scheme (Bullard et al., 2011) in the Chihuahuan Desert (Baddock et al., 2011) where 48% of satellite-observed plumes were sourced from ephemeral and dry lakes. Six landforms were tested: 1) ephemeral and 2) dry lake, 3) high and 4) low relief alluvial, and aeolian 5) sand sheet and 6) dunes. …

250, Scott Brande

All 3D Rock Models

Model 250 - anthracite - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/250-a7f41cbcebd449eda33f60c19c9d33f9

149, Scott Brande

All 3D Rock Models

Model 149 - pegmatite - igneous rock

SketchFab link: https://sketchfab.com/3d-models/149-eea34817eff94fd49ba8117d0de7a7ad

Can Phytoremediation-Induced Changes In The Microbiome Improve Saline/Sodic Soil And Plant Health?, Achal Neupane, Duncan Jukubowski, Douglas Fiedler, Liping Gu, Sharon A. Clay, David E. Clay, Shin-Yi Marzano

Agronomy, Horticulture and Plant Science Faculty Publications

Increasing soil salinity and/or sodicity is an expanding problem in the Northern Great Plains (NGP) of North America. This study investigated the impact of phytoremediation on the soil microbiome and if changes, in turn, had positive or negative effects on plant establishment. Amplicon sequencing and gas chromatograph/mass spectrometer analysis compared root metabolites and microbial composition of bulk vs. rhizosphere soils between two soil types (productive and saline/sodic). Beta-diversity analysis indicated that bacterial and fungal communities from both the bulk and rhizosphere soils from each soil type clustered separately, indicating dissimilar microbial composition. Plant species also influenced both root-associated bacterial and …

153, Scott Brande

All 3D Rock Models

Model 153 - peridotite - igneous rock

SketchFab link: https://sketchfab.com/3d-models/153-352bbb86b3bf42239154c9b226f18881

161, Scott Brande

All 3D Rock Models

Model 161 - bituminous coal - sedimentary rock

SketchFab link: https://sketchfab.com/3d-models/161-2393ea8889df42b186b9dcd19afeebb6

170, Scott Brande

All 3D Rock Models

Model 170 - chalk - sedimentary rock

SketchFab link: https://sketchfab.com/3d-models/170-df8b420304fd4e6fb879981978811f74

Uqsees-P8, Scott Brande

All 3D Rock Models

Model UQSEES-P8 - obsidian - igneous rock

SketchFab link: https://sketchfab.com/3d-models/uqsees-p8-427b9a83af65469c9124945cf1d648ef

195, Scott Brande

All 3D Rock Models

Model 195 - travertine - sedimentary rock

SketchFab link: https://sketchfab.com/3d-models/195-8012a646b8d4422396efe1d939f9f947

255, Scott Brande

All 3D Rock Models

Model 255 - hornfels - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/255-92eb561fa0234e15b68b1bef86bd3ca7

Probable Extirpation Of The Jackrabbit (Lepus Californicus) From Arkansas, D.B. Sasse

Journal of the Arkansas Academy of Science

The black-tailed jackrabbit (Lepus californicus) was first documented in Arkansas during the modern era in Franklin County in 1927. Over the next few decades records were reported from multiple counties in northwest Arkansas and the species was locally common in Benton, Crawford, and Washington counties in the 1950s. The last Arkansas record documented in the scientific literature was from 1968 and since then there have only been three credible reports, with the last being from the late 1980s. The Arkansas Game and Fish Commission solicited reports of jackrabbits from the public and failed to find evidence of them from a …

Ultrastructure Of The Biflagellated Spermatozoon In The Western Siren, Siren Nettingi (Caudata: Sirenidae), Using Scanning Electron Microscopy, S.E. Trauth

Journal of the Arkansas Academy of Science

I investigated the ultrastructure of the biflagellated spermatozoon of the Western Siren, Siren nettingi, using scanning electron microscopy from salamanders collected in northeastern Arkansas. My primary goal in this study was to reveal the general morphology of the distinctive sperm cell components (two axonemes, two undulating membranes, and two axial fibers), which run nearly the entire length of the spermatozoon. These remarkable gamete structures are found in members of the salamander family Sirenidae and do not conform to spermatozoal ultrastructure of any other salamander species. Moreover, the biflagellated sperm are the end product of an extraordinary assemblage of complex maturation …

History And Distribution Of The Wood Stork (Mycteria Americana) In Arkansas, R. Tumlison, L. Serviss

Journal of the Arkansas Academy of Science

Wood Storks (Mycteria americana) were thought to be common visitors to Arkansas in the early 1900s, but observations declined mid-century. Surveys of citizen science data and other online sources indicate that numbers of unique observations and total counts of birds have increased since 2000. Storks do not breed here, but have been reported in 34 of 75 counties, and appear mostly in August and September. Birds apparently originate from Mexico. Number of observations have increased since 2016, but many of those observations include only a few birds rather than larger flocks.

An Annotated Checklist Of The Camel Crickets (Insecta: Orthoptera: Rhaphidophoridae) Of Arkansas, H.W. Robison, C.T. Mcallister

Journal of the Arkansas Academy of Science

A total of 14 native species of camel crickets and one introduced taxon representing three genera (Ceuthophilus, Phrixocnemis, and Diestrammena) of the orthopteran family Rhaphidophoridae, are herein reported from Arkansas. The most diverse genus was Ceuthophilus, with 13 native species, while Phrixocnemis had one native species, and Diestrammena, formerly Tachycines, was represented by one introduced species. This updated checklist is intended to be of use to entomologists, naturalists, professional biologists, and resource managers in evaluating the biodiversity of Arkansas. State distributional maps are provided for each species listed by county, and habitats are discussed in which each species was taken …

Fish Leeches Of Arkansas, D.J. Richardson, W.E. Moser, C.T. Mcallister, S.P. Lawson, H.W. Robison

Journal of the Arkansas Academy of Science

Recent collection within Arkansas greatly enlarges the knowledge concerning hosts and distributions of fish leeches within the state. The natural history of the 6 species of fish leeches known from Arkansas (Placobdella montifera, Placobdella pediculata, Cystobranchus klemmi, Cystobranchus verrilli, Myzobdella lugubris, and Myzobdella reducta) is reviewed and updated and molecular data are provided.

Petrophysics Characterization With Multiple Sample Scales Of Cuttings, Cores And Well Logs For Different Rock Types, Ogochukwu Azike

Earth & Environmental Sciences Dissertations - Archive

Petrophysics Characterization with Multiple Sample Scales of Cuttings, Cores and Well Logs for Different Rock Types

Laboratory-based experimental evaluations and nuclear magnetic resonance log data interpretation of carbonates, sandstones and shale rocks enable multi-scale petrophysical parameters characterization for integrated studies that can be applied in both the industry and academia. Numerous studies have been published on pore geometry and connectivity, as well as the diffusivity, migration, and containment of a fluid (oil/gas/water) in different reservoir types. However, despite the importance of diffusion and imbibition as a transport mechanism especially in unconventional resources, the direct measurements of these parameters have been …

Thermochronology And Exhumation Dynamics Of Metamorphic Units In The Salmon River Suture Zone, Jonathan J. Cone

Graduate Theses/Dissertations

The Salmon River suture zone in western Idaho records the Jurassic-Cretaceous (160-90 Ma) accretion of amalgamated volcanic arc terranes onto the North American continent. Rocks exposed at the surface record burial to depths of more than 20 kilometers, with unclear drivers for uplift and exhumation. Two competing hypotheses have been proposed to explain the transport of deep crustal rocks to the surface: (1) delamination of a dense lithospheric root resulted in rapid isostatic uplift of the crust and (2) exhumation of crustal blocks along thrust faults. To test these models, I present temperature-time (T-t) paths for mid-crustal metamorphic rocks constructed …

Geology Of The Bishop 7.5-Minute Quadrangle And Geophysical Modeling To Constrain Syndepositional Deformation Of The Black Warrior Foreland Basin, Joseph Edward Lane

Graduate Theses/Dissertations

The Black Warrior basin is a foreland basin formed by the Ouachita–Appalachian orogeny during the late Paleozoic Era. Mississippian strata record the transition from the carbonate platform within the Tuscumbia Limestone to the clastic-rich units within the overlying Pride Mountain Formation and Hartselle Sandstone. The western and southern-most fringes of the Black Warrior basin are covered by thin, post orogenic Cretaceous sediments of the East Gulf Coastal Plain. Geological mapping of the Bishop 7.5-Minute quadrangle revealed subtle deformation in Mississippian strata in the form of gentle folds (

Bank Erosion Dynamics In Response To Anthropogenic Disturbances In The Cuivre River Watershed Of Missouri, Usa, Nathan Douglas Sines

Graduate Theses/Dissertations

Riverbank erosion is increasingly recognized as a pressing issue exacerbated by human activities. The Cuivre River, a tributary of the Mississippi River, located in northeast Missouri, has limited documentation on bank erosion, with the most recent study conducted in the early 1990s. This research aims to fill this gap by exploring the stream bank erosion dynamics from 1816 to 2015. The objectives are to: (i) understand the channel width dynamics for 1816 to 1994 ii) determine the sediment erosion and deposition volume along the riverbank in the period of 1994 to 2015. iii) identify the anthropogenic disturbances particularly land use …

Origin Of Carbonate Mud Mounds In Southwestern Missouri, Jared Mcavoy

Graduate Theses/Dissertations

Small carbonate mud mounds are found in Lower Mississippian strata of southwestern Missouri. These compare favorably with larger mounds, known as Waulsortian mounds, located in the Meuse River valley of southern Belgium. The origin of Waulsortian and similar mounds is unknown, but they commonly are interpreted as accumulations of mud, where the presence of biological organisms responsible for supposed bio-construction remains uncertain. Alternative hypotheses are that these may have been non-cohesive slump or cohesive slide masses. Multiple techniques, including δ13C and δ18O isotopic analyses and unmanned aerial vehicle photography, were used to determine the most feasible working hypothesis. Determining the …

Hydrogeomorphic Response Of Fluvial Systems To Climate Change - An Example From James River, Missouri, Afrida Aranya

Graduate Theses/Dissertations

Climate change has led to unpredictable hydrological patterns, significantly altering the fluvial environment and their flow regime. Despite extensive research, our knowledge about the impacts of climate change on flow regimes in the US Midwest is limited, particularly in karst-dominated fluvial landscapes. This research addresses this gap by investigating the effects of climatic change on the hydrogeomorphology of the James River, located in the karst-dominated Ozark Highlands in southwest Missouri, USA. The study focuses on two ~1.5 km stream segments—one relatively active and one stable in the context of geomorphology—near Springfield, Missouri. The research aims to (i) understand the changing …

Million-Year Melt-Presence In Mogollon-Datil Volcanic Field Rhyolites: Constraining The Histories Of The Bursum Caldera Resurgent Domes, Ethan Wagner

Graduate Theses/Dissertations

The Mogollon-Datil volcanic field which is located in southwestern New Mexico, is the result of punctuated volcanism and the transition between arc and rift magmatism. The resurgent domes within the 28 Ma Bursum caldera records the transition from rhyolitic to basaltic andesite volcanism that occurred between 27-26 Ma. Using a combination of new zircon U-Pb ages using chemical abrasion isotope dilution thermal ionization mass spectrometry (CA-ID-TIMS) with zircon U-Pb geochronology and trace element contents by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and whole rock and mineral trace element contents and isotope geochemistry this study investigates the temporal and …

Water Quality Of A Karstic Shallow Aquifer In Greene And Lawrence Counties, Missouri, Claudia Patricia Colmenero Chacon

Graduate Theses/Dissertations

A water quality investigation in the Springfield Plateau aquifer of Greene and Lawrence counties, Missouri, was conducted. Water samples from eleven springs were collected at regular intervals during 2023 to determine major water quality parameters: total dissolved solids (TDS), alkalinity, calcium (Ca), magnesium (Mg), sodium (Na), sulfate (SO₄), chloride (Cl) and nitrate-nitrogen (NO₃-N), along with per- and poly-fluorinated alkali substances (PFAS) from spring sediments. Nitrate-nitrogen was analyzed because of the importance for environmental health (e.g. to avoid eutrophication). Springs samples were separated by land use into urban and rural samples. In addition, Springfield Plateau water quality …

Geodatabase And Automation Code Used For Past And Real-Time Dynamic Landslide Hazard Maps In Eastern Kentucky, Nathaniel O'Leary, L. Sebastian Bryson, Jason M. Dortch

Earth and Environmental Sciences Research Data

We developed spatiotemporal landslide hazard maps (LHMs) using soil, hydrologic, and geomorphic parameters from the subaerial infinite slope factor of safety (FS) equation under unsaturated conditions. Soil properties were sourced from the NRCS WSS, while geomorphic variables were derived from a 1.5 m LiDAR-based DEM and ArcGIS Online. Soil moisture from Hydrus-1D, driven by precipitation and evapotranspiration (ET) data from Irrigation Manager, introduced temporal variability. Validation against known landslide sites demonstrated FS accuracy both spatially and temporally, despite some false positives. To reduce false positives and enhance slope stability representation, novel depth-to-bedrock (DTB) and soil root cohesion maps were incorporated …

Crowdsourced Geospatial Data Is Reshaping Urban Sciences, Xiao Huang, Siqin Wang, Tianjun Lu, Yisi Liu, Leticia Serrano-Estrada

Earth and Environmental Sciences Faculty Publications

For many years, urban sciences relied heavily on traditional, authoritative data sources. However, a paradigm shift has occurred recently with the advent of citizen-driven data contribution. This evolution in data acquisition for urban science is attributable to advancements in positioning and navigation technologies, widespread use of digital devices, the rise of Web 2.0, enhanced broadband communications, and refined data management techniques. The significance of crowdsourced geospatial data in the realm of urban sciences is now widely acknowledged. A diverse array of novel data sources has been increasingly gaining prominence. These include, but are not limited to, social media platforms, street …

Crowdsourcing Geospatial Data For Earth And Human Observations: A Review, Xiao Huang, Siqin Wang, Di Yang, Tao Hu, Meixu Chen, Mengxi Zhang, Guiming Zhang, Filip Biljecki, Tianjun Lu, Lei Zou, Connor Y. H. Wu, Yoo Min Park, Xiao Li, Yunzhe Liu, Hongchao Fan, Jessica Mitchell, Zhenlong Li, Alexander Hohl

Earth and Environmental Sciences Faculty Publications

The transformation from authoritative to user-generated data landscapes has garnered considerable attention, notably with the proliferation of crowdsourced geospatial data. Facilitated by advancements in digital technology and high-speed communication, this paradigm shift has democratized data collection, obliterating traditional barriers between data producers and users. While previous literature has compartmentalized this subject into distinct platforms and application domains, this review offers a holistic examination of crowdsourced geospatial data. Employing a narrative review approach due to the interdisciplinary nature of the topic, we investigate both human and Earth observations through crowdsourced initiatives. This review categorizes the diverse applications of these data and …

Impacts Of Anthropogenic Sedimentation On Shell-Bed Habitats In Lake Tanganyika, Africa, Michael Soreghan, Andrew Cohen, Michael M. Mcglue, Kevin M. Yeager, Emily Ryan, Alison Johns, Ishmael Kimirei

Earth and Environmental Sciences Faculty Publications

Lake Tanganyika, in central Africa, contains a diverse and endemic fauna under threat from global climate change, overfishing, and nearshore sediment pollution. Previous studies of sediment pollution focused justifiably on impacts along rocky shorelines where diversity is high, but Lake Tanganyika also contains widespread shelly accumulations (shell beds) unprecedented in the modern East African lakes, but where impacts are less con- strained. Here we integrate multiple datasets from three sites along the Tanzanian shoreline to explore how variation in sedimentation rates and sediment quality impacts shell-bed substrate and diversity and abundance of ostracodes and sponges across sites that exhibit varying …