Earth Sciences Commons^™

Seasonal Transport Of Dissolved Inorganic Carbon And Total Alkalinity Across The Louisiana Shelf, Michelle M. Anderson

LSU Master's Theses

Rivers and wetlands are a major source of terrestrial derived carbon for coastal ocean margins. Unfortunately, Louisiana’s wetlands are threatened by ongoing high rates of erosion, deterioration, and unprecedented rates of river water discharge that changes seasonally, leading to a net loss of terrestrial carbon into the northern Gulf of Mexico (nGOM). There exists a current lack of understanding about the distribution of dissolved inorganic carbon (DIC) and total alkalinity (TAlk) within the shallowest regions of the Louisiana shelf. Even less is known about how the transport of DIC alters seasonally with changes in river outflow and shelf currents. Quantifying …

Speleothems In Quartz-Sandstone Caves Of Ponta Grossa Municipality, Campos Gerais Region, Paraná State, Southern Brazil, Henrique S. Pontes, Luiz A. Fernandes, Mário S. De Melo, Gilson B. Guimarães, Laís L. Massuqueto

International Journal of Speleology

The present communication characterizes and discusses the genesis of cave speleothems developed in Furnas Formation (Silurian-Devonian) and Vila Velha sub-unit (Campo Mourão Formation, Upper Carboniferous) quartz-sandstones, in southern Brazil. The research, which involved stratigraphic and petrographic studies, was conducted to identify the faciological context of occurrence of these features, and to determine, through different analytical methods, their mineralogical composition and porosity, and also the action of microbial markers on the genesis of these secondary mineral deposits. The speleothems were classified into six types based on form, composition and genesis: (1) arborescent (coral), (2) mushroom-shaped, (3) stalactitic, (4) stalagmitic, (5) columnar …

Grazing Summer‐Active Tall Fescue In South‐Eastern Australia, Margaret Raeside, Michael A. Friend, Alister Lawson

IGC Proceedings (1977-2023)

No abstract provided.

Seasonal Dynamics Of The Rangeland's Vegetations Of Arid Zone Of Uzbekistan, Bakhtiyor K. Mardonov, Wolfgang Pittroff, Toshpulot F. Rajabov, F. N. Bobodjanov

IGC Proceedings (1977-2023)

No abstract provided.

Preliminary Investigations On Columbus Grass (Sorghum Almum Parodi) For Fodder In Semi‐Arid Nigeria: Effects Of Sowing Methods On Growth Components And Herbage Yield, B. S. Malami, H. M. Tukur, H. Dahiru

IGC Proceedings (1977-2023)

No abstract provided.

Forage Potential Of Alfalfa (Medicago Sativa L.) For Wildlife, D. Maćešić, S. Sikora, Z. Svečnjak, D. Uher

IGC Proceedings (1977-2023)

No abstract provided.

Developing And Implementing A 100% Renewable Electricity Resolution: A Research-Based Framework, Emily E. Skill, Roslynn Brain Mccann, Sarah C. Klain

All Current Publications

While it may seem that the efforts of local governments have only a marginal impact on the global issue of climate change, local action can spread to generate large-scale change. Local action can inspire other communities to adopt policies, creating the potential to expand and form regional action on climate change. Furthermore, local policies can influence state and federal policies. This guide will walk you through a five-step framework that was developed from the results of a qualitative research study that explored how three Utah cities, Salt Lake City, Park City, and Moab, successfully adopted 100% renewable electricity resolutions.

Nanomineralogy Of Evaporative Precipitation Of Efflorescent Compounds From Coal Mine Drainage, Luis F. O. Silva, Diana Pinto, Guilherme L. Dotto, James C. Hower

Earth and Environmental Sciences Faculty Publications

Efflorescent nanophases (NPs) are found as a transitory accumulation of potentially hazardous elements (PHEs), particularly in tropical climates. The central objective of this study was to investigate the distribution of PHEs with NPs through the evaporative formation structures (EFS) of enormously PHEs-rich coal-mine drainages (CMD). The EFS were studied in natural coal mine drainage for five months in order to determine their geochemical and ecological structures and to assess their position in the reduction of PHEs in nature. The largest coal-fired power plant in South America, located in south Brazil, is used as an example of such a problem. In …

Sediment Transport And Geomorphological Evolution In The Transgressive Ship Shoal, Louisiana: Insights From Geophysical Observation, Modeling, And Machine Learning Studies, Haoran Liu

LSU Doctoral Dissertations

Ship Shoal has been a high-priority target sand resource for dredging activities to restore the eroding barrier islands in Louisiana, USA. Many studies have been performed in Ship Shoal in recent decades, but our knowledge of temporal and spatial variations of sediment transport and post-dredge morphology is still limited. The objectives of this dissertation are to explore the sediment infilling process, the spatial and temporal evolution of the morphology of dredge pits near and on Ship Shoal by using multiple methods. Scientific methods used in this study include (a) geophysical observation using bathymetry, side-scan and subbottom technique, (b) sediment transport …

Combined Use Of Sentinel‐1 Sar And Landsat Sensors Products For Residual Soil Moisture Retrieval Over Agricultural Fields In The Upper Blue Nile Basin, Ethiopia, Getachew Ayehu, Tsegaye Tadesse, Berhan Gessesse, Yibeltal Yigrem, Assefa M. Melesse

National Drought Mitigation Center: Faculty Publications

The objective of this paper is to investigate the potential of sentinel‐1 SAR sensor products and the contribution of soil roughness parameters to estimate volumetric residual soil moisture (RSM) in the Upper Blue Nile (UBN) basin, Ethiopia. The backscatter contribution of crop residue water content was estimated using Landsat sensor product and the water cloud model (WCM). The surface roughness parameters were estimated from the Oh and Baghdadi models. A feed‐forward artificial neural network (ANN) method was tested for its potential to translate SAR backscattering and surface roughness input variables to RSM values. The model was trained for three inversion …

Noise Characteristics Of Operational Real‐Time High‐Rate Gnss Positions In A Large Aperture Network, Diego Melgar, Brendan W. Crowell, Timothy I. Melbourne, Walter Szeliga, Marcelo Santillan, Craig Scivner

Geological Sciences Faculty Scholarship

Large earthquakes are difficult to model in real‐time with traditional inertial seismic measurements. Several algorithms that leverage high‐rate real‐time Global Navigation Satellite Systems (HR‐GNSS) positions have been proposed, and it has been shown that they can supplement the earthquake monitoring effort. However, analyses of the long‐term noise behavior of high‐rate real‐time GNSS positions, which are important to understand how the data can be used operationally by monitoring agencies, have been limited to just a few sites and to short time spans. Here, we show results from an analysis of the noise characteristics of 1 year of positions at 213 GNSS …

Cosmogenic Nuclide Dating Of Cave Sediments In The Eastern Alps And Implications For Erosion Rates, Philipp Häuselmann, Lukas Plan, Peter Pointner, Markus Fiebig

International Journal of Speleology

Karstic caves are created by water eroding and corroding rocks that can be dissolved. Since both the spring areas of caves (normally at the valley bottom) as well as the recharge is controlled by superficial processes, the morphology of the cave bears strong links to these influences. Lowering of local base levels promotes the development of horizontal phreatic cave passages at progressively lower elevations, resulting in the formation of multi-level karst systems. Upon the next lowering of base level, these upper systems become fossilized, and sediment trapped within them may remain preserved for millions of years. Dating these sediments gives …

Recent Shrinkage And Fragmentation Of Bluegrass Landscape In Kentucky, Bo Tao, Yanjun Yang, Jia Yang, S. Ray Smith, James F. Fox, Alex C. Ruane, Jinze Liu, Wei Ren

Plant and Soil Sciences Faculty Publications

The Bluegrass Region is an area in north-central Kentucky with unique natural and cultural significance, which possesses some of the most fertile soils in the world. Over recent decades, land use and land cover changes have threatened the protection of the unique natural, scenic, and historic resources in this region. In this study, we applied a fragmentation model and a set of landscape metrics together with the satellite-derived USDA Cropland Data Layer to examine the shrinkage and fragmentation of grassland in the Bluegrass Region, Kentucky during 2008–2018. Our results showed that recent land use change across the Bluegrass Region is …

Wrack & Ruin: A Tale Of Tortured Trees, John T. Van Stan Ii, Albertus Tyasseta, Siloy, Graphic Artist

Earth, Environment & Sustainability: Faculty Bookshelf

Here, we visit a community of trees living along the Georgia coast, just above the high tide line, on a little lump of sand called a "hammock." This hammock plant community is battered by a hurricane. The plants that survive soon realize that they have fallen prey to a hydrological torture wrack - one composed of the salty corpses of their neighboring marsh plants (Spartina alterniflora). This sci comic is based on the publication, "Wrack and ruin: Legacy hydrologic effects of hurricane-deposited wrack..." (https://doi.org/10.1088/2515-7620/ab9527).

Investigating Geochemical Processes Of Fluid-Rock Interactions On Materials Related To Energy And Environment, Zelong Zhang

LSU Doctoral Dissertations

Understanding the potential processes of radionuclides released from nuclear waste forms is essential to the safe disposal and containment of nuclear waste. Iodoapatite, a potential waste form for radioiodine, was chosen as a model system to examine the impact by common aqueous anions on iodine release processes. Four semi-dynamic leaching tests were performed using 0.1 mol/L NaCl, Na₂CO₃, Na₃PO₄, and Na₂SO₄ solutions respectively under 90 °C, 1 bar, fixed S/V ratio 5/m (sample surface area to solution volume), and with 24-hour replacement of the leaching solutions. Solution analysis and …

Heavy Metals In The Arctic: Distribution And Enrichment Of Five Metals In Alaskan Soils, Clarice R. Perryman, Jochen Wirsing, Kathryn A. Bennett, Owen Brennick, Apryl L. Perry, Nicole Williamson, Jessica G. Ernakovich

Faculty Publications

Metal contamination of food and water resources is a known public health issue in Arctic and sub-Arctic communities due to the proximity of many communities to mining and drilling sites. In addition, permafrost thaw may release heavy metals sequestered in previously frozen soils, potentially contaminating food and water resources by increasing the concentration of metals in freshwater, plants, and wildlife. Here we assess the enrichment of selected heavy metals in Alaskan soils by synthesizing publicly available data of soil metal concentrations. We analyzed data of soil concentrations of arsenic, chromium, mercury, nickel, and lead from over 1,000 samples available through …

Wrack And Ruin: Legacy Hydrologic Effects Of Hurricane-Deposited Wrack On Hardwood-Hammock Coastal Islands, John T. Van Stan Ii, Scott T. Allen, Travis Swanson

Earth, Environment & Sustainability: Faculty Publications

Hurricanes can cause immediate catastrophic destruction of marsh vegetation and erosion of soils; however, they also have long-lasting ecological impacts. Those impacts include the deposition of tremendous amounts of saltmarsh litter ('wrack') onto upland ecosystems, the hydrologic effects of which have not previously been investigated. When Hurricane Irma battered the southeastern US coastline, widespread wrack deposition was reported (often exceeding 0.5 m depth), especially in vulnerable coastal hammock ecosystems: locally-elevated forests within the saltmarshes that rely on freshwater inputs from rain. We report the impacts of this deposited wrack, which has persisted for 2 years, on effective precipitation inputs to …

The Effect Of Soil Ph On Phosphorus Content Of Clover Pasture, David Weaver, Robert Summers, David Rogers, Peta Richards

Resource management technical reports

Testing of pasture soils from 2009 to 2018, as part of DPIRD’s Whole Farm Nutrient Mapping (WFNM) project in the coastal catchments of south-west Western Australia (WA), indicated that soil pH was so low it could be limiting plant access to nutrients. Observations by some farmers who had been involved in the soil testing were that lime application had not increased pasture production, even when pH_Ca (pH measured in calcium chloride) tests indicated that phosphorus (P) should become more available by increasing soil pH. Farmers also wanted to know if they needed to apply more P than soil testing …

Integrating Detailed Petrography, Geochemistry, And Mineralogy To Elucidate Extensive Early Diagenesis In The Eocene Carbonates Of Qatar, Brooks H. Ryan

Dissertations

Eocene carbonates comprising the Umm er Radhuma (UER), Rus, and Dammam Formations, cover 80% of the surface and extend >300 m into the subsurface of Qatar. These rocks record marine sedimentation in shallow sub-tidal to restricted settings. Despite undergoing only shallow burial (<1000 m), extensive diagenetic alteration has occurred. Given that little work on this topic has been published previously, the objectives of this work are to document diagenesis in the Eocene, and to integrate petrography, mineralogy, and geochemistry to delineate the timing and environments of diagenesis of these Eocene carbonates. Detailed petrographic data show that dolomitization occurred early in the UER, before the formation of diagenetic chert, palygorskite, pyrite, calcite, and gypsum cements. Bulk dolomite δ¹⁸O values, coupled with clumped isotope-derived (Δ47) temperatures and dolomitizing fluid δ¹⁸O values, suggest dolomitization took place in near-normal marine fluids, perhaps during shallow burial. These data challenge the current paradigm of large-scale, top-down hypersaline reflux dolomitization in the UER. Associated depth trends of increasing crystal size and with increasing stoichiometry and cation ordering …

A Hydrometeorological Assessment Of The Historic 2019 Flood Of Nebraska, Iowa, And South Dakota, Paul Xavier Flanagan, Rezaul Mahmood, Natalie Umphlett, Erin M.K. Haacker, Chittaranjan Ray, Bill Sorensen, Martha Shulski, Crystal J. Stiles, David Pearson, Paul Fajman

High Plains Regional Climate Center: Staff Publications

During early 2019, a series of events set the stage for devastating floods in eastern Nebraska, western Iowa, and southeastern South Dakota. When the floodwaters hit, dams and levees failed, cutting off towns, while destroying roads, bridges, and rail lines, further exacerbating the crisis. Lives were lost and thousands of cattle were stranded. Estimates indicate that the cost of the flooding has topped $3 billion as of August 2019, with this number expected to rise.

After a warm and wet start to winter, eastern Nebraska, western Iowa, and southeastern South Dakota endured anomalously low temperatures and record-breaking snowfall. By March …

Evaluation Of Iceberg Calving Models Against Observations From Greenland Outlet Glaciers, Tristan Amaral, Timothy C. Bartholomaus, Ellyn M. Enderlin

Geosciences Faculty Publications and Presentations

Frontal ablation processes at marine‐terminating glaciers are challenging to observe and difficult to represent in numerical ice flow models, yet play critical roles in modulating ice sheet mass balance. Current ice sheet models typically rely on simple iceberg calving models to prescribe either terminus positions or iceberg calving rates, but the relative accuracies and uncertainties of these calving models remain largely unconstrained at the ice sheet scale. Here, we evaluate six published iceberg calving models against spatially and temporally diverse observations from 50 marine‐terminating outlet glaciers in Greenland. We seek the single model that best reproduces observed conditions across all …

Estimating Evapotranspiration Of A Riparian Forest Using Sap Flow Measurements, James R. Solum

Master's Theses

To close the water use budget of irrigated agricultural fields in floodplains with substantial riparian corridors, it is necessary to understand groundwater usage by dominant phreatophytic vegetation, particularly when the primary source of water for irrigation comes from groundwater abstraction. We report here results of estimated evapotranspiration (ET) of a riparian forest, which were based on measurements of sap flow in phreatophytic vegetation within a riparian corridor. The riparian corridor was within a study area 75 to 140 meters wide in the lower portion of the Scotts Creek watershed, which is bounded to the west by the Pacific Ocean in …

Host Plant Resistance In Strawberries To Anthracnose And Colonization Of Crown And Root Tissue By Verticillium Dahliae And Macrophomina Phaseolina, Omar A. Gonzalez-Benitez

Master's Theses

Strawberries are considered an important crop in California where in 2018 it was in the top 5 valued fruit and vegetable commodities valued at $2.84 billion accounting for 88% of the total U.S. production. Strawberry production can be severely impacted by soilborne pathogens that can affect strawberry roots, crowns and leaves which can result in plant mortality. As much as 50 to 60% mortality can occur in one field. Pathogens responsible for such losses include Colletotrichum acutatum (syn.C. nymphaeae), Macrophomina phaseolina and Verticillium dahliae. With the phaseout of methyl bromide, host resistance and an understanding of host-pathogen interactions …

The Strawberry Rhizosphere Microbiome: Role On Plant Health And Nutrition, Eric Michael Boyd

Master's Theses

Microbial-root associations are important to help plants cope with abiotic and biotic stressors. Managing these interactions offers an opportunity for improving the efficiency and sustainability of agricultural production. By characterizing the bacterial and archaeal community (via 16S rRNA sequencing) associated with the bulk and rhizosphere soil of sixteen strawberry cultivars in two controlled field studies, we explored the relationships between the soil microbiome and plant resistance to two soilborne fungal pathogens of strawberry (Verticillium dahliae and Macrophomina phaseolina). Overall, the plants had a distinctive rhizosphere microbiome relative to the bulk soil, with higher abundances of known beneficial bacteria …

Does Updating Natural Hazard Maps To Reflect Best Practices Increase Viewer Comprehension Of Risk?, Carson C. Macpherson-Krutsky, Brittany D. Brand, Michael K. Lindell

Geosciences Faculty Publications and Presentations

In this study, we examine whether updating an interactive hazard map using recommendations from the literature improves user map comprehension. Analyses of experimental data collected from 75 university students revealed that map comprehension scores were not significantly better for those who viewed a “best practices” map compared to those who viewed an existing version. This may be because the existing map was itself better than most other interactive maps. Additionally, we found map comprehension levels to have significant positive relationships with objective tests, but not self-reported measures of spatial ability. Moreover, self-reported spatial ability had statistically significant, but only moderately …

Analysis Of Antarctic Peninsula Glacier Frontal Ablation Rates With Respect To Iceberg Melt-Inferred Variability In Ocean Conditions, M. C. Dryak, E. M. Enderlin

Geosciences Faculty Publications and Presentations

Marine-terminating glaciers on the Antarctic Peninsula (AP) have retreated, accelerated and thinned in response to climate change in recent decades. Ocean warming has been implicated as a trigger for these changes in glacier dynamics, yet little data exist near glacier termini to assess the role of ocean warming here. We use remotely-sensed iceberg melt rates seaward of two glaciers on the eastern and six glaciers on the western AP from 2013 to 2019 to explore connections between variations in ocean conditions and glacier frontal ablation. We find iceberg melt rates follow regional ocean temperature variations, with the highest melt rates …

An Integrated Approach (Remote Sensing, Hydrogeology, Gis, And Statistical Modeling) To Identify The Distribution Of Shallow Groundwater Occurrences Over Southwest Saudi Arabia, Fahad Khudier Alshehri

Dissertations

Identifying shallow (near-surface) groundwater in arid and hyper-arid areas has significant societal benefits, yet it is a costly operation when traditional methods (geophysics and drilling) are applied over large domains. In this study, we developed and successfully applied methodologies that rely heavily on readily available temporal, visible and near-infrared, radar, and thermal remote sensing data sets and field data, as well as statistical approaches to map the distribution of shallow (1–5 m deep) groundwater occurrences in Al Qunfudah Province, Saudi Arabia and to identify the factors controlling their development. A four-fold approach was adopted: (1) constructing a digital database to …

Controls On Microbial And Oolitic Carbonate Sedimentation And Stratigraphic Cyclicity Within A Mixed Carbonate-Siliciclastic System: Upper Cambrian Wilberns Formation, Llano Uplift, Mason County, Texas, Usa, Daniel J. Lehrmann, A. W. Droxler, P. Harris, M. Minzoni, Dylan A. Droxler, H. H. Hopson, Caroline Kelleher, P. Khanna, Asmara A. Lehrmann, Adrien Lhemann, Grace Mabry, Lauren Mercado, J. M. Proctor, Pulkit Singh, Lindesy D. Yazbek

Earth and Environmental Geosciences Faculty Research

The upper Cambrian Wilberns Formation in central Texas records deposition on a low-gradient shelf within a mixed carbonate–siliciclastic tidal-flat system that changes offshore to subtidal shelf and open-marine oolitic skeletal shoals with large microbial mounds. Siliciclastic sediment is interpreted to have been delivered to the tidal flat by aeolian processes because of the narrow range in grain size and paucity of clay. Tidal influence is dominant as evidenced by reversing currents and desiccation on the tidal flat, and megaripples with reversing current indicators in offshore shoals. Intraclastic conglomerates were deposited in broad channels on the tidal flats during storm surges. …

Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson

Electronic Theses and Dissertations

Sediment gravity flows into deep-water environments are important stratigraphic traps in lithologically diverse reservoirs generating multiple plays for hydrocarbon exploration. These highly heterogeneous deposits can be studied by utilizing chemostratigraphy and higher-order sequence stratigraphy; being an accurate method for reservoir characterization. Studying these gravity flows along a carbonate platform’s slope can further expand an understanding of the stratigraphy that is filling adjacent basins. The application of elemental analyses can support in identifying mineralogy that impact reservoir quality, especially when conventional testing cannot be applied.

This study utilizes five cores containing the Wolfcamp Formation from the southeastern slope of the Central …

Non-Toxic Soil Thickeners For Reducing Mudslide Intensity, Mitchell William Jensen

Materials Engineering

This project was intended to be a continuation of senior project work done last year by a group consisting of two Materials Engineering students and a Soil Science student. Their report was crucial in identifying a range of food thickeners that could be capable of performing in the mud thickening application. All thickeners that were chosen both this year and last year are biocompatible, to alleviate some toxicity concerns. The food thickeners all belong to a class of compounds known as colloids. Since water is the fluid being thickened, these compounds are more accurately referred to as hydrocolloids. Hydrocolloids are …