Earth Sciences Commons^™

Water Relations In Native Trees, Northeastern Mexico, Humberto González, I. A. Molina, I. C. Silva, M. V. Gómez, R. G. Ramírez

IGC Proceedings (1977-2023)

No abstract provided.

Effects Of Different Utilization Levels On Species Richness Changes In Saral Grassland, Kurdistan Province, S. Gholinejad, M. Vafakhah, S. A. R. Mousavi

IGC Proceedings (1977-2023)

No abstract provided.

Behavior Of Medicinal Species Of Cichorium Intybus Against Salinity On Different Developmental Stages, M. Ghavam Arabani, Hossein Azarnivand, A. Tavili

IGC Proceedings (1977-2023)

No abstract provided.

Modeling Fluoride Contamination In Groundwater And Its Spatial Association: An Indian Perspective, Arundhati Mohanty

Manipal Institute of Technology, Manipal Theses and Dissertations

The effects of fluoride on groundwater have been studied earlier, but all those studies have been area specific. This study expanded its boundaries, and covered the entire Indian sub-continent with over eight lakh ground water samples(gws) using random-sampling for pre- and post-monsoon data, rainfall data, lithology of India, and various other statistics as its data. The main objective of this study was to model fluoride contamination in groundwater along with its spatial association using different spatial analyst tools, interpolation tools etc in ArcGIS 10.6.1, in order to understand the trend of fluoride contamination in various parts of India and to …

Carbon And Nitrogen Isotope Ratios Of Chemosynthetic Biota From The Active Cold Seep Site Of, K-G Basin, Bay Of Bengal, Tanojit Paul

Manipal Institute of Technology, Manipal Theses and Dissertations

The study area in the K-G basin is a cold seep ecosystem and contains shallow methane gas hydrates (2-3 mbsf), discovered for the first time in the Indian Exclusive Economic Zone (EEZ) which is associated with methane gas flares in the water column. This methane rich gas is released into the surrounding environment which supports an extensive range of endemic organisms and plants, and it continues to be one of the most extravagant ecological system of the seabed. The methane released from the seep site reacts with the overlying seawater and over time they form carbonate rocks which is an …

Understanding The Geodynamic Evolution Of Central And Eastern Indian Ocean By Geophysical Interpretation, Brandis Dominic Carlier

Manipal Institute of Technology, Manipal Theses and Dissertations

The aim of this study is to understand the complex geodynamics of the Central and Eastern Indian Ocean using different geophysical methods. The methods used are, magnetism, gravity and surface heat flow. Understanding water column depth is an important factor and hence, bathymetry data was also used. This report encompasses a brief understanding of the study area with respect to the morphological features present and its tectonic evolution. In the methodology section, the explanation to how and from where the raw data was procured for all the geophysical parameters mentioned above is discussed. The various data processing procedures involved and …

Hydrogeochemical Characterization And Speleogenesis Of Sistema Huautla In Oaxaca, Mexico, Fernando Hernandez

Masters Theses & Specialist Projects

Sierra Mazateca, Mexico is home to Sistema Huautla, the deepest cave in the Western hemisphere with 1,560 meters of depth and 90 kilometers of passage, including 26 entrances distributed in a high-relief, karstified terrain, within the Sistema Huautla Karst Groundwater Basin. Exploration of the cave has generated research questions about its evolution and geomorphology given the different vadose and phreatic zones impacted by tectonic and incision processes. Dye traces during this study of Cueva de La Peña Colorada confirmed it is a fossil resurgence of the cave system. An additional cave, Cueva Elysium, was connected hydrologically in 2019, expanding the …

Using The Electromagnetic Induction Survey Method To Examine The Depth To Clay Soil Layer (Bt Horizon) In Playa Wetlands, Yuan Xue, Zhenghong Tang, Qiao Hu, Jeff Drahota

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

Purpose Sediment accumulation has been and continues to be a significant threat to the integrity of the playa wetland ecosystem. The purpose of this study was to determine the vertical depth to the clay soil layer (Bt horizon) and thus to calculate the thickness of sediments accumulated in playa wetlands.

Materials and methods This study used the electromagnetic induction (EMI) survey method, specifically EM38-MK2 equipment, to measure the vertical depth to the clay soil layer at the publicly managed wetlands in the Rainwater Basin, Nebraska, USA.

Results and discussion The results indicated that the depth to the clay soil layer …

Monitoring The 2018 Eruption Of Kīlauea Volcano Using Various Remote Sensing Techniques, Ninad Bhagwat

Graduate Theses & Non-Theses

Monitoring the regions that are prone to natural hazards is essential in disaster management to provide early warnings. Airborne and space-borne remote sensing techniques are cost-effective in accomplishing this task. Interferometric Synthetic Aperture Radar (InSAR) is an advanced remote sensing technique used to detect and measure the changes in the Earth’s topography over time. Spaceborne InSAR is a precise (~mm accuracy) way to measure the land surface altitudinal changes. Persistent Scatterer Interferometry (PSI) is a powerful method of differential SAR interferometry that processes the InSAR data by automatically selecting the persistent scatterers in the region. In this thesis, I developed …

Soil Labile Organic Carbon Fractions And Soil Enzyme Activities After 10 Years Of Continuous Fertilization And Wheat Residue Incorporation, Ligan Zhang, Xi Chen, Yujun Xu, Mengcan Jin, Xinxin Ye, Hongjian Gao, Wenying Chu, Jingdong Mao, Michael L. Thompson

Chemistry & Biochemistry Faculty Publications

Labile organic carbon (LOC) fractions and related enzyme activities in soils are considered to be early and sensitive indicators of soil quality changes. We investigated the influences of fertilization and residue incorporation on LOC fractions, enzyme activities, and the carbon pool management index (CPMI) in a 10-year field experiment. The experiment was composed of three treatments: (1) no fertilization (control), (2) chemical fertilizer application alone (F), and (3) chemical fertilizer application combined with incorporation of wheat straw residues (F + R). Generally, the F + R treatment led to the highest concentrations of the LOC fractions. Compared to the control …

Droughtscape, Summer 2020, National Drought Mitigation Center

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

DroughtScape, Summer 2020

Digital Mapping Of Togo’S Soil Fertility: Savannah Region, Aminou Saibou

International Programs

A soil assessment was carried out in the savannah region of Togo in 2018, aiming at drawing the digital map of Togo’s soil fertility and making fertilizer recommendations. Soil samples were taken from geo-referenced GPS points and were analyzed for parameters such as water pH, Organic matter, available phosphorus and exchangeable potassium. Thematic maps have been drawn using an ArcGIS package. The results showed that the soils of the Savannah region in Togo are mainly (84%) not very acidic (pH = 5.5 to 6.5), overall poor to very poor (84%) in organic matter (<2% OM), essentially poor to very poor (86%) in available phosphorus (<15 mg/kg of soil) and mostly very poor (87%) in exchangeable potassium (<90 mg / kg of soil). These results allowed the agricultural research institute of Togo to make fertilizer use recommendations and to develop, in partnership with Morocco, a digital platform (fertitogo.tg ) for decision making in crop fertilization.

Groundwater Storage Loss Associated With Land Subsidence In Western United States Mapped Using Machine Learning, Ryan G. Smith, Sayantan Majumdar

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Land subsidence caused by groundwater extraction has numerous negative consequences, such as loss of groundwater storage and damage to infrastructure. Understanding the magnitude, timing, and locations of land subsidence, as well as the mechanisms driving it, is crucial to implementing mitigation strategies, yet the complex, nonlinear processes causing subsidence are difficult to quantify. Physical models relating groundwater flux to aquifer compaction exist but require substantial hydrological data sets and are time consuming to calibrate. Land deformation can be measured using interferometric synthetic aperture radar (InSAR) and GPS, but the former is computationally expensive to estimate at scale and is subject …

Pystprism: Tools For Voxel-Based Space–Time Prisms, Rebecca Loraamm, Joni A. Downs, James Anderson, David S. Lamb

School of Geosciences Faculty and Staff Publications

The observed movements of humans and animals are realizations of complex spatiotemporal processes. Recent advances in location-aware technologies have rendered trajectory data ubiquitous. Examining the sequenced, instantaneous locations found in movement trajectory data for information reconstructing the location or state of the mover between observed points comprises a primary focus in Time Geography and related disciplines. The PySTPrism toolbox introduced in this paper provides a straightforward and open-source implementation of the Probabilistic Space Time Prism, in addition to related tools from Time Geography. PySTPrism is implemented in Python using the ArcPy module in ArcGIS Pro Desktop.

Dynamics And Impacts Of The May 8th, 1902 Pyroclastic Current At Mount Pelée (Martinique): New Insights From Numerical Modeling, Valentin Gueugneau, Karim Kelfoun, Sylvain J. Charbonnier, Aurelie Germa, Guillaume Carazzo

School of Geosciences Faculty and Staff Publications

The Mount Pelée May 8th, 1902 eruption is responsible for the deaths of more than 29,000 people, as well as the nearly-complete destruction of the city of Saint Pierre by a single pyroclastic current, and is, sadly, the deadliest eruption of the 20th century. Despite intensive field studies on the associated deposit, two conflicting interpretations of the pyroclastic current dynamics (either a blast or a simple ash-cloud surge) emerged in the 90’s and have been paralyzing research ever since, leaving numerous unknowns (i.e., source conditions, volume). This study is the first to investigate numerically the May 8th, 1902 pyroclastic …

Characterizing Peridotite Xenoliths From Southern Vietnam: Insight Into The Underlying Lithospheric Mantle, Kirby Hobbs

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

Extrusion tectonics has been invoked to explain the extensive basaltic magmatism that has erupted over Indochina within the last 17 Ma. The basalts display two-stage eruptive cycles consisting of tholeiites followed by alkaline basalts. Lithospheric mantle xenoliths recently sampled from the alkaline basalts of two volcanic centers, Pleiku and Xuan Loc, primarily consist of fertile spinel lherzolites, and Xuan Loc also contains refractory spinel harzburgites. We measured major elements in xenolith mineral separates, trace elements in clinopyroxenes and orthopyroxenes, and Pb-Sr-Nd isotopic compositions in clinopyroxenes to determine the origin and history of the subcontinental lithospheric mantle (SCLM) beneath Vietnam. Most …

Geophysical Survey Near Center, North Dakota, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about an intended geophysical survey near Center, North Dakota. Data gathering is part of Project Tundra and North Dakota CarbonSAFE. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Geophysical Survey Near Milton R. Young Station, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about an intended geophysical survey near Milton R. Young Station. Data gathering is part of Project Tundra and North Dakota CarbonSAFE. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

The Influence Of Human Disturbance On Wildlife Use Of A Highway In South Texas, Thomas J. Yamashita

Theses and Dissertations

Roads can greatly impact wildlife. Wildlife vehicle collisions contribute to population declines while disturbance from human activity may prevent wildlife from using areas around roads. The construction of mitigation structures may lessen these effects through fine scale modification of animal use of roadside areas. In this thesis, how the construction of wildlife mitigation structures impacted the fine scale distribution of wildlife on State Highway 100 in Cameron County, Texas was examined. Spatial and temporal scale may also influence these relationships. The relationship between human activity and wildlife activity around the highway was explored and how the distribution of wildlife road …

Probability Distributions Of Particle Hop Distance And Travel Time Over Equilibrium Mobile Bedforms, Robert C. Mahon, Ashley C. Thomas, Suleyman Naqshband, Kate C. P. Leary, Brandon Mcelroy

Earth and Environmental Sciences Faculty Publications

The joint probability distribution of streamwise particle hop distance, lateral particle hop distance, and travel time constrains the relationships between topographic change and sediment transport at the granular scale. Previous studies have investigated the ensemble characteristics of particle motions over plane bed topography; however, it is unclear whether reported distributions remain valid when bedforms are present. Here, we present measurements of particle motion over bedform topography obtained in a laboratory flume and compare these to particle motions over plane bed topography with otherwise similar conditions. We find substantial differences in particle motion in the presence of bedforms that …

Analysis Of The Facilitative Interaction Between Batis Maritima And Avicennia Germinans As A Mangrove Restoration Strategy, Javier R. Navarro

Theses and Dissertations

The multiple experiments conducted in an Avicennia germinans forest in Laguna Vista, TX was focused on determining if facilitation theory could explain the behavior observed between the herbaceous halophyte Batis maritima and A. germinans. I hypnotized that a positive interaction exists but through which mechanisms of facilitation I did not know. The overarching theme of the study is the presence or absence of B. maritima. Facilitation theory tells us that positive interactions are most often found under stressful conditions such as those on the coastal tidal flat of the Laguna Madre. Locally B. maritima has been found to …

Overexpression Of Strigolactone-Associated Genes Exerts Fine-Tuning Selection On Soybean Rhizosphere Bacterial And Fungal Microbiome, Fang Liu, John Hollis Rice, Valeria Lopes, Parwinder Grewal, Sarah L. Lebeis, Tarek Hewezi, Margaret E. Staton

School of Earth, Environmental, & Marine Sciences Faculty Publications

Strigolactones are a recently discovered class of carotenoid-derived plant hormones with a wide variety of functions, including acting as signaling molecules in the rhizosphere to promote arbuscular mycorrhizal fungi colonization and parasitic seed germination. To determine whether strigolactones influence the recruitment of microbes to the rhizosphere, we characterized both bacterial and fungal communities in response to the overexpression of genes involved in strigolactone biosynthesis (MAX1d) and signaling perception (D14 and MAX2a) in soybean (Glycine max). The amplicon sequencing-based results suggest that strigolactone overexpression lines had altered soybean rhizosphere bacteria composition at both the community …

A Bayesian Framework To Unravel Food, Groundwater, And Climate Linkages: A Case Study From Louisiana, Nitin K. Singh, Ruchi Bhattacharya, David M. Borrok

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Advancing our understanding of the connections among groundwater, food, and climate is critical to meet global food demands while optimizing water resources usage. However, our understanding of the linkages among groundwater, food, and climate is still limited. Here, we offer a Bayesian framework to simulate crop yield at a regional scale and quantify its relationships and associated uncertainty with climate, groundwater, agricultural, and energy-related variables. We implemented the framework in the rice-producing regions of Louisiana from 1960-2015. To build a parsimonious model, we used a probability-based variable selection approach to detect the key drivers of rice yield. Rice yield increased, …

An Experimental Investigation Of Liquid Hydrocarbons In A Simulated Titan Environment, Kendra Farnsworth

Graduate Theses and Dissertations

Saturn’s moon, Titan, has surface conditions (89–94 K, 1.5-bar atmosphere) that permit lakes of methane, ethane, and dissolved atmospheric nitrogen. The effects of atmospheric nitrogen on methane-ethane liquid properties is poorly understood, leading to uncertainty in Titan modeling. I address this question by experimentally investigating the physical properties of methane-ethane liquids under a 1.5-bar nitrogen atmosphere in a simulated Titan environmental chamber.

Chapter 1 addresses nitrogen dissolution kinetics in Titan’s liquid hydrocarbons. I found an exponential increase in nitrogen quantity and diffusion coefficients with increasing methane mol%. I find that Titan’s liquids are likely not saturated in nitrogen, with dissolution …

Novel Quantification Of Shallow Sediment Compaction By Gps Interferometric Reflectometry And Implications For Flood Susceptibility, Makan A. Karegar, Kristine M. Larson, Jurgen Kusche, Timothy H. Dixon

School of Geosciences Faculty and Staff Publications

Estimates of flood susceptibility and land loss in the world's coastal regions depend on our knowledge of sea level rise (SLR) from increases in ocean mass and volume, as well as knowledge of vertical land motion. Conventional approaches to the latter include tide‐gauge and Global Positioning System (GPS) measurements relative to well‐anchored monuments few meters below the surface. However, in regions of rapid Holocene sedimentation, compaction of this material can add a significant component to the surface lowering. Unfortunately, this process has been difficult to quantify, especially for the shallowest material above the monument. Here we use a new technique, …

Earthworm Dynamics In Tallgrass Prairies In The Ozark Highlands Region Of Northwest Arkansas, Carlee Hensley

Graduate Theses and Dissertations

Tallgrass prairie was a historic and is presently a unique and endangered natural ecosystem throughout the Ozark Highlands region in the mid-southern United States. Tallgrass prairies have been disturbed for agricultural production and/or urban expansion; thus, as a result, efforts have been undertaken to reclaim areas previously used for agricultural production to mitigate the loss of tallgrass prairies. Limited research exists on earthworm dynamics in mounded tallgrass prairies or prairie restorations, particularly in the Ozark Highlands region of northwest Arkansas. The objectives of this study were to i) evaluate the effects of soil moisture regime (SMR; aquic and udic), landscape …

Geospatial Analyses Of Seismic Hazards And Risk Perception In Libya, Somaia Suwihli

Graduate Theses and Dissertations

Libya is not considered a highly active seismic region. However, several earthquakes of magnitude >5.0 have occurred there. This dissertation analyzes the seismicity of Libya in order to better understand earthquake hazards, related geomorphic features, and the current evolution of Libyan perceptions of seismic risk. The first article developed a baseline of past and current seismic inventory in Libya, which represented an assessment of Libya seismic hazard by translating, analyzing, and compiling historical sources and archaeological data. This study shows that Libya has experienced earthquakes in varying degrees since ancient times. Through the spatial and temporal distribution of earthquakes from …

Using Soil Geospatial Properties And Environments To Explore Microbial Diversity, Sharon Faye Smith

Graduate Theses and Dissertations

Soil microorganisms help maintain nutrient cycling, control carbon sequestration, impact plant productivity, and influence several soil chemical and physical properties; yet, the processes that control the microbial composition of soil and how environmental changes may affect the composition and activity of these organisms at different scales remains a difficult and intriguing puzzle for soil scientists, ecologists, and modelers. Wetlands are endangered and important ecosystems that provide several services, which are directly linked to soil function. However, few wetland assessments consider the soil environment and microbial ecology. Linking soil microbial community composition and distribution patterns to soil physio-chemical properties would provide …

Environmental Influences On Tree-Driven Karst Bedrock Physical Weathering, Cole Robert Jimerson

Graduate Theses and Dissertations

The role of tree roots as stressors that contribute to physical weathering processes and thus soil generation remains an open question in critical zone science. While evidence suggests roots may be able to damage rock by accessing pre-existing fractures, where they can expand due to water uptake or generate forces on rock in response to wind gusts, these processes have not been investigated in temperate karst regions until now. I monitored forces at the root-rock interface for an American elm and Hackberry tree between September 2019 and May 2020. I used piezoelectric force sensors to determine if differences in species, …

Effects Of Terrestrial Weathering On Rare Earth Element Concentrations And Sulfur Isotopic Signatures Of Carbonaceous And Ordinary Chondrites, Ruby Virginia Patterson

Graduate Theses and Dissertations

Understanding the effects of weathering of chondrites is essential to gaining accurate and useful information about the formation of our solar system, as well as a more detailed account of the mobilization of chondritic compounds when they encounter terrestrial conditions. Elemental concentrations and stable isotope analyses of chondrites, considered to be the most primordial material in the solar system, are two tools which help unlock the weathering patterns of these specimens when they enter the earth system. However, it is not currently known exactly how time spent in the field alters rare earth element (REE) concentration or δ34S signatures within …