Digital Commons Network^™

Machine Learning Predicts Aperiodic Laboratory Earthquakes, Olha Tanyuk, Daniel Davieau, Charles South, Daniel W. Engels

SMU Data Science Review

In this paper we find a pattern of aperiodic seismic signals that precede earthquakes at any time in a laboratory earthquake’s cycle using a small window of time. We use a data set that comes from a classic laboratory experiment having several stick-slip displacements (earthquakes), a type of experiment which has been studied as a simulation of seismologic faults for decades. This data exhibits similar behavior to natural earthquakes, so the same approach may work in predicting the timing of them. Here we show that by applying random forest machine learning technique to the acoustic signal emitted by a laboratory …

Water Productivity In Meat And Milk Production In The Us From 1960 To 2016, Mesfin Mekonnen, C.M.U. Neale, Chittaranjan Ray, Galen E. Erickson, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Global demand for livestock products is rising, resulting in a growing demand for feed and potentially burdening freshwater resources to produce this feed. To offset this increased pressure on water resources, the environmental performance of livestock sector should continue to improve. Over the last few decades, product output per animal and feedstuff yields in the US have improved, but before now it was unclear to what extent these improvements influenced the water productivity (WP) of the livestock products. In this research, we estimate changes in WP of animal products from 1960 to 2016. We consider feed conversion ratios (dry matter …

Geomorphic And Land Use Controls On Headwater Channel Morphology In Mark Twain National Forest, Grace F. Roman

Graduate Theses/Dissertations

Prescribed burning has been used over the past two decades to manage forests and restore shortleaf pine-oak woodlands in Mark Twain National Forest (MTNF). While soil studies have been completed, no assessments of burning practices on small drainage channel systems have yet been done. Headwater streams may account for more than two-thirds of total stream length and are important to the maintenance of hydrologic connectivity in watersheds. This study’s focus is on understanding the relationship between frequency of forest burning and channel morphology (size, shape, and substrate) of headwater streams (km²). A combination of field measurements, geo-processing methods, …

The Archaeology Of Mississippian Vulnerability And Resilience In The New Madrid Seismic Zone, Michelle Megan Rathgaber

Graduate Theses and Dissertations

This work examines the vulnerability and resilience of Mississippian people in the Central Mississippi Valley to the large-scale New Madrid seismic zone earthquakes of the late15th to early 16th century. This is done using the theory of eventful archaeology/anthropology to look at cultural materials both before and after an event (such as an earthquake and sand blows) to look for evidence of changes to the schema and resources on which a society relies. If changes are present, the event can be labeled as such, if there are no changes, it means that the society affected did not see the event …

Microbial Community, Functioning, And Its Relationship With Heavy Metals In An Urban Brownfield, Jay Prakash Singh

Theses, Dissertations and Culminating Projects

The ubiquity of urban brownfields presents a challenge for environmental managers for managing degraded ecosystems that are in close contact with human habitation. Presence of metal contaminants in brownfields further complicate the matters as it cannot be degraded and hence pose a high risk to human and environmental health, and well-being of the local community. However, previous studies indicate that management and restoration of brownfields are possible through the use of low input longer term and sustainable remediation approaches. These sustainable approaches include the use of plants, fungi, and bacteria to increase soil function and mitigate risks from the contaminants. …

Stable Isotope And Geochemical Characterization Of Nutrient Sources In The Big Creek Watershed Of Northwest Arkansas, Kelly Robin Sokolosky

Graduate Theses and Dissertations

The establishment of a concentrated animal-feeding operation (CAFO) in Newton County, Arkansas near Big Creek, a tributary of the Buffalo National River, has raised concern over potential degradation of water-quality in the watershed. In this study, isotopic tools were combined with standard geochemical approaches to characterize nutrient sources and dynamics in Big Creek. An isotopic and geochemical reference library of potential nutrient sources in the Big Creek watershed was established by direct sampling of representative potential sources, including septic-system effluent, poultry litter, swine and cattle manure, and CAFO waste lagoons. Representative nutrient sources and Big Creek stream samples were analyzed …

Assessing Bioavailability, Metal Fractionation, Magnetic Susceptibility, And Organic Matter Interactivity In Mine-Waste Contaminated Sediments In Turkey Creek, Joplin, Missouri, Zachary Joseph Collette

Graduate Theses/Dissertations

Joplin, Missouri, part of the Tri-State Mining District (TSMD), has a long history of mining that resulted in mine waste piles proximal to the mines throughout the area. A local lead smelter also resulted in smelter fallout in Joplin. Mine waste pile runoff and local smelter fallout resulted in contamination of sediments, soils, and waterways. In the 1990s, remediation of residential soils and play areas began after blood lead levels in children were much higher than the national average. Soon afterwards, the chat piles were removed and used for beneficial reuse purposes. In May of 2011, an EF5 tornado devastated …

Insights Into The Evolution Of The Galápagos Archipelago And Its Mantle Source From Monogenetic Near-Island Seamounts, Darin M. Schwartz

Boise State University Theses and Dissertations

Lavas erupted at ocean island volcanoes are classically used as probes of the deep Earth, with ultimate goals of discerning the compositional heterogeneity, structure and dynamics of the Earth’s mantle. However, sampling restricted to volcanic islands and large, submarine volcanic constructs alone likely results in limited spatial resolution of the mantle’s composition and structure, owing to homogenization in sub-island magma reservoirs. Further, islands provide poor temporal resolution given that their multigenetic construction can overprint any time progressive chemical variations and they subside with age making detailed sampling difficult. For my dissertation I investigate whether seamounts surrounding islands in the Galápagos …

Application Of Semi-Hydrophobic Layers To Decrease Bare Soil Evaporation, Jesse Lee Barnes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evaporative water loss from bare agricultural soils is a primary area of water conservation research. Mulching is the commonly utilized method to decrease evaporative water loss. The most commonly utilized mulch is nonbiodegradable polyethylene sheeting because it tends to decrease evaporative water loss and increase crop yields more than environmentally friendly mulches. This study aimed to test the utility of sand coated with polymerized soybean oil (i.e., hydrophobic sand) as a treatment to reduce bare soil evaporation and an alternative to current practices. Evaporation rates were measured in laboratory soil columns containing both treated and untreated soils. Treatment parameters were …

Comparing Structure From Motion Photogrammetry And Computer Vision For Low-Cost 3d Cave Mapping: Tipton-Haynes Cave, Tennessee, Clinton Elmore

Electronic Theses and Dissertations

Natural caves represent one of the most difficult environments to map with modern 3D technologies. In this study I tested two relatively new methods for 3D mapping in Tipton-Haynes Cave near Johnson City, Tennessee: Structure from Motion Photogrammetry and Computer Vision using Tango, an RGB-D (Red Green Blue and Depth) technology. Many different aspects of these two methods were analyzed with respect to the needs of average cave explorers. Major considerations were cost, time, accuracy, durability, simplicity, lighting setup, and drift. The 3D maps were compared to a conventional cave map drafted with measurements from a modern digital survey instrument …

Evaluating Responses Of Benthic Macrofauna To Artificial Reef Presence In The Gulf Of Mexico, Douglas Faircloth

Theses and Dissertations

Artificial reef research has long concerned itself with the interactions of fishes and has tended to favor commercially valuable species. Because of this, a larger yet less known group that heavily benefits fishes have been overlooked; benthic macrofauna. Benthic macrofauna are marine invertebrates that live below the sediment-water interface and play many roles in the ecosystem. Macrofauna are important prey items, ecosystem engineers, and bioindicators, as well as being ubiquitous in the marine environment. Since macrofauna have been largely ignored in this field, not much is known regarding their interaction with the placement of artificial reefs. To try and fill …

Sand And Pumice Filter Amended With Activated Carbon And Biochar For Phosphorus Retention, James Jihoon Kang, Marissa Davila, Sergio I. Mireles, Jungseok Ho

School of Earth, Environmental, & Marine Sciences Faculty Publications

Phosphorus (P) loss via stormwater runoff is a water quality concern. The objective of this study was to investigate two commercial biochars relative to an activated carbon as an additive to geomedia (sand and pumice) for P removal. The batch adsorption experiment was conducted to assess P sorption of the geomedia and carbon materials while the leaching experiment was conducted in sand and pumice columns amended with carbon materials (5 % by weight). The batch adsorption test revealed that only activated carbon showed an appreciable P adsorption up to 19 %. Tested biochar materials showed no adsorption capacity for P …

Changes In Mammalian Abundance Through The Eocene–Oligocene Climate Transition In The White River Group Of Nebraska, Usa, Robert Gillham

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

Marine records show major cooling during the Eocene-Oligocene Climate Transition (EOCT). Most proxy studies in the White River Group suggest drying across the EOCT, and some suggest cooling. The lower resolution continental record has hindered a direct correlation of the marine climate record to Nebraska. I explore various correlation schemes and what they imply for faunal changes. This study compiles and analyzes data from 4,875 specimens in the University of Nebraska State Museum (UNSM) collection to test the hypothesis that climate change across the Eocene-Oligocene (E-O) boundary caused significant abundance changes in mammals. A series of binning schemes was created. …

Drought Analyses Of The Horn´E PoˇZitavie Region (Slovakia) In The Period 1966–2013, Jaroslav Vido, Paulina Nalevankova, Jan Valach, Zbysek Sustek, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

+is study focuses on the characterization of historical drought occurrences in the Horn´e Poˇzitavie region of Slovakia over the period 1966–2013 using Standardized Precipitation-Evapotranspiration Index (SPEI). Trend analyses were evaluated by the Mann–Kendall (MK) test as well as cumulative sum of rank difference (CRD) test. +e results showed that drought occurs in the region regularly (recurrent climate feature), while the trend analysis indicated the trend toward more arid climatic conditions. However, CRD trend analyses showed that the subtrend changed direction toward less drier conditions in the late 1980s and early 1990s. Analyses of SPEI trends in individual months showed a …

Early Mississippian Ocean Anoxia Triggering Organic Carbon Burial And Enhancing Late Paleozoic Ice Age Onset: Evidence From Uranium Isotopes Of Marine Limestones, Keyi Cheng

Earth and Planetary Sciences ETDs

The Early Mississippian (Tournaisian) positive δ¹³C excursion (or TICE) is one of the largest recorded in the Phanerozoic and the organic carbon (OC) burial associated with its development is hypothesized to have driven global cooling and increased glaciation. We are testing the hypothesis that expanded ocean euxinia/anoxia drove widespread OC burial and the TICE and we are testing this hypothesis using uranium isotopes (δ²³⁸U) of Lower Mississippian marine limestones from southern Nevada as a global seawater redox proxy.

δ²³⁸U trends record a prominent mid-Tournaisian negative excursion (~0.30‰ magnitude) lasting ~1 My. The lack of …

Evaluating Fluid Fluxes From Deep-Sea Seepage Habitats, Leigha E. Peterson

Electronic Theses and Dissertations

The permanently dark deep-sea, located at oceanic water depths greater than 200 m, represents the largest potential habitat space on Earth. The physicochemical conditions of the planet’s largest biome are tightly coupled to the exchange of matter and energy from terrestrial and sea-floor end-members. In fact, global ocean and climate systems are significantly impacted by deep-sea processes. Seafloor vents and seeps appear to act as geologic exchange conduits, returning recycled materials to the hydrosphere to sustain another generation of life. Despite submarine seepage having control on global elemental cycling, it is estimated that less than 1% of the deep-sea has …

Crop And Climate Suitability For Irrigated Agriculture In The Midlands Area Of Western Australia, 2nd Edition, Leon Van Wyk

Resource management technical reports

The Midlands groundwater and land assessment is a $4.7 million Water for Food project. Its aim is to confirm groundwater availability at one or more focus areas that may form precincts of 2000–3000 hectares suitable for intensive irrigated horticulture. This report forms part of this project.

Firstly, this report describes the climate of the Midlands study area and highlights the subtle differences between the two selected focus areas, Irwin and Dinner Hill. It discusses the importance of climate in determining crop suitability. We also investigated the following additional factors that determine crop suitability: water quality, water quantity, land capability (soils) …

Lithological Character And Sequence Stratigraphy Of The Ste. Genevieve Limestone In Western Kentucky, Zachary Dalton Creech

Masters Theses & Specialist Projects

The Ste. Genevieve Limestone is a Mississippian-aged, carbonate-dominated stratigraphic unit that is a prominent hydrocarbon producer in the Illinois Basin, and is widely distributed in states such as Missouri, Kentucky, Indiana, and Illinois. There has been relatively limited study focused on characterizing the Ste. Genevieve Limestone in terms of lithofacies, stacking patterns, and sequence stratigraphic context via analysis of roadcut exposures of the unit in western Kentucky.

The focus of this study is to use lithologic data collected from roadcuts and draft these data into cross sections for presentation of detailed stratigraphic columns that are locally correlative. Seven roadcuts were …

The Effectiveness Of Mobile Eye-Tracking To Enhance Guided Show Cave Experiences, Jenna Michele Hammond

Masters Theses & Specialist Projects

Karst terrains are landscapes with a distinctive hydrology and set of landforms that arise from a combination of high bedrock solubility and well-developed secondary (fracture) porosity. Karst areas are easily polluted due to the rapid transport of unfiltered percolating water through the systems. While many individuals are able to identify karst landforms such as sinkholes and caves, an understanding of the interconnectedness of the surface and subsurface in karst landscapes, as well as the vulnerability of karst areas to degradation, is often limited. Show caves, which are caves made accessible to visitation by humans through built infrastructure, can serve as …

Droughtscape, Fall 2019, Cory Matteson

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the Director

Quarterly drought summary

Quarterly drought impacts

Ranchers delayed response to drought

Drought Monitor celebrates 20 years

Drought Monitor state impact tables

Directorcontributesto U.N.droughtproject

Updated Drought Risk Atlas

New fact sheet lists recovery resources

Droughtscape, Summer 2019, Cory Matteson

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the Director

Quarterly drought summary

Quarterly drought impacts

NDMC welcomes African visitors

Ready for Drought game debuts

U.S. Virgin Islands added to USDM

Australian programmer visits NDMC

Upcoming events

Partnerships with NDMC extended

Earth News, V42, Summer 2019, University Of Northern Iowa. Department Of Earth And Environmental Sciences.

Earth News

Inside this issue:
--From the Department Head
--Faculty Updates
--SGE Chapter News
--Student Recognition
--Sunday at the Quarry
--Student Spotlight
--Student Research
--Hydrology News
--Faculty and AIPG Awards
--A Trip to New Mexico
--Big Bend 2018
--The Importance of Geology
--Field Work
--Alumni Updates
--Gifts from Alumni & Friends
--Contribution Form

Persistence Of Depositional Features In A Strongly Seasonal, Tide-Dominated Delta, Kallie Flaxington Brown

OES Theses and Dissertations

The Ganges-Brahmaputra-Meghna (GBM) Delta is one of the largest deltas in the world, covering more than 100,000 km². The GBM River system transports over one billion tons of sediment annually and delivers ~750 million tons to the Bay of Bengal, ~25% of which is advected by tides into the fluvially abandoned western delta plain. The Sundarbans National Forest (SNF) is located within the GBM Delta and, covering more than 10,000 km², is the world’s largest continuous mangrove stand. The present rate of sediment delivery allows the SNF platform elevation to keep pace with regional sea level …

Lipid Biomarkers Of Bering And Chukchi Sea Euphausiids And Their Application To Diet History, Rachel L. Pleuthner

OES Theses and Dissertations

In the eastern Bering Sea, Thysanoessa raschii are the most abundant krill species and a keystone trophic member that serve as both an important grazer and link to upper level consumers. In this system krill experience large annual variation in food resources, especially during ice advance and retreat; multiple lipid classes are used to temper the effects of those fluctuations, as well as to fuel reproduction and growth. Two shipboard feeding experiments that occurred during late spring and early summer of 2010, respectively, monitored the lipid retention in adult T. raschii and examined the fluctuation of specific lipid biomarkers under …

Determining The Impacts Of The Anthropocene Through Time-Calibrated Taphonomic Grading, Nicole Seiden, Gregory S. Herbert

School of Geosciences Faculty and Staff Publications

Global biodiversity loss threatens ecosystem integrity and related services for humans, but most communities lack baseline data to assess the magnitude of change. In marine conservation, molluscan death assemblages are increasingly being used as a proxy for baseline communities, and divergence between the live and the dead is assumed to reflect human impact. A drawback to partitioning an assemblage into live and dead is that inclusion of recently dead specimens in the baseline assemblage artificially reduces differences between before and after. In this study, we address this problem by using a radiocarbon- and amino acid-calibrated taphonomic grading scale to partition …

Climate Change Impacts On Winter Wheat Yield In Northern China, Xiu Geng, Fang Wang, Wei Ren, Zhixin Hao

Plant and Soil Sciences Faculty Publications

Exploring the impacts of climate change on agriculture is one of important topics with respect to climate change. We quantitatively examined the impacts of climate change on winter wheat yield in Northern China using the Cobb–Douglas production function. Utilizing time-series data of agricultural production and meteorological observations from 1981 to 2016, the impacts of climatic factors on wheat production were assessed. It was found that the contribution of climatic factors to winter wheat yield per unit area (WYPA) was 0.762–1.921% in absolute terms. Growing season average temperature (GSAT) had a negative impact on WYPA for the period of 1981–2016. A …

Unexplored Diversity Of The Mesophotic Echinoderm Fauna Of The Easter Island Ecoregion, Ariadna Mecho, Erin E. Easton, Javier Sellanes, Matthias Gorny, Christopher Mah

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Easter Island ecoregion (EIE) is one of the most remote marine areas of the world and encompasses a vast and fragile ecosystem including oceanic islands and seamounts. In January 2014 and March 2016, a remotely operated vehicle was used to explore a subsurface peak off Easter Island (27.23°S, 109.48°W) and a seamount (26.92°S, 110.26°W), respectively located 10 km southwest and 98 km west of the island. More than 950 echinoderms were observed in the 5 h of video recorded during the seven dives conducted at depths between ~ 160 and 280 m. The communities of echinoderms observed at these …

The Cation Exchange Behavior Of Tylosin In Loess-Derived Soil, Jaime J. Call, Michael E. Essington, Sudipta Rakshit

Agricultural and Environmental Sciences Faculty Research

Tylosin (Tyl) is a veterinary antibiotic commonly used in swine and poultry production. Due to metabolic inefficiencies, it enters the environment through manure applications. Ion exchange is an important retention mechanism for Tyl, particularly for smectite clay. The objectives of this study are to characterize the exchange interactions of Tyl with common soil cations in subsoil horizons that contain smectite and to investigate the interactions using in situ Fourier transform infrared (FTIR) spectroscopy. Adsorbed Tyl in pH neutral, smectitic subsoil horizons is divided into exchangeable and nonexchangeable forms. The percentage of adsorbed Tyl that is exchangeable varies from 36% to …

Development Of An Rfid Tracking System For Coarse Sediment Transport In A Flume Setting, Peter Mahoney Jr.

ENGS 88 Honors Thesis (AB Students)

Development of an RFID Tracking System for Coarse Sediment Transport in a Flume Setting

Peter E. Mahoney

Professor Carl Renshaw

Understanding how sediment moves through a fluvial system has important implications for the study of river systems, sediment flux, and flood events. Over the past decade, RFID (radio frequency identification) technology has emerged as a useful method for tracking the movement and transport of coarse sediment clasts. This approach has been used to measure the transport of large clasts in mid-sized streams, ephemeral channels, and laboratory flume settings. However, this research utilized finite transport of sediment and focused on accurately …

Characterization Of Cross-Bed Depositional Processes In The Coconino Sandstone, Sarah A. Maithel

Loma Linda University Electronic Theses, Dissertations & Projects

The Permian Coconino Sandstone of northern and central Arizona is widely recognized as a classic eolian dune deposit, with conspicuous large-scale cross-beds that are interpreted as preserved dune foresets. On modern bedforms, fine-scale processes – which include grainflow, grainfall, and ripple migration – transport and deposit sediment, and these may provide useful analogs for interpreting ancient deposits. Even though the Coconino Sandstone is well known, such fine-scale process models have not been adequately developed to explain its cross-bed deposition. Furthermore, observed discrepancies between the sandstone and some eolian criteria suggest that additional study is needed to explore and refine these …