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The Influence Of Intensity Of Tree Thinning On The Redistribution Of Soil Water In Southern African Mopani Veld, G N. Smit, N F.G. Rethman, A Moore, A Le Roux, J S. Swart

IGC Proceedings (1977-2023)

The investigation was conducted on a densely wooded area in the Mopani veld of South Africa. Six plots were subjected to different intensities of tree thinning, ranging from a totally cleared plot (0 %) to plots thinned to the equivalent of 10%, 20%, 35%, 50% and 75% of the leaf biomass of a control plot (100%). Soil water measurements were taken at six different depths to a depth of 825 mm. The infiltration of rain water and redistribution within the soil profile exhibited marked differences between experimental plots. The soil water was predominantly held at a very shallow depth ( …

Relationship Of Visual And Quantitative Methods Of Grass Sward Development, R B. Mitchell, L E. Moser, K J. Moore

IGC Proceedings (1977-2023)

The objective of this study was to determine the relationship between visual and quantitative estimates of the morphological development of perennial grass swards. Pure stands of intermediate wheatgrass [Thinopyrum intermedium (Host) Barkw. & D.R. Dewey] and switchgrass (Panicum virgatum L.) were hand-clipped to ground level at 2-wk intervals in 1991 at Mead, NE, morphologically classified as mean stage count (MSC), and visually estimated for sward development. Visual estimations of sward development for both species were representative of quantitative measurements during vegetative growth. However, as sward development advanced to the elongation and heading stages, visual methods over-estimated the population …

Morphological Development Rates Of Perennial Forage Grasses, R B. Mitchell, L E. Moser, K J. Moore, D D. Redfearn

IGC Proceedings (1977-2023)

The objective of this study was to determine the rate of change in the morphological development of switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerardii Vitman). Pure stands of each species were sampled at weekly intervals in 1990 and 1991 at Mead, NE, and morphologically classified as mean stage count (MSC) and mean stage weight (MSW). Linear day of the year equations accounted for 94% of the variation in switchgrass MSC and MSW. Switchgrass MSC and MSW increased at an average rate of 0.0204 and 0.0234 units per day, respectively. Linear day of the year equations accounted …

Fertilizer Nitrogen And Morphogenetic Response In Avena Sativa And Lolium Multiflorum, F Lattanzi, M A. Marino, A Mazzanti

IGC Proceedings (1977-2023)

A field experiment was carried out at the EEA Balcarce, INTA, Argentina (37° 45’LS, 58° 18’LW) to determine whether Leaf Appearance Rate (LAR) was affected by N fertilization in Italian ryegrass (Lolium multiflorum Lam.) and forage oats (Avena sativa). N treatments (0, 50, 100, 150, 200 and 250 kg N ha-1) were applied in winter 1995, after a defoliation. Subsequently, number of leaves per tiller was determined on 45 labelled tillers in each treatment twice a week. LAR was calculated as the slope of the linear regression of number of leaves on thermal time (air temperature, base …

Allocation Of Carbon-14 To Roots Of Different Ages In Perennial Ryegrass (Lolium Perenne L.), C Matthew, W D. Kemball

IGC Proceedings (1977-2023)

The objective of this study was to provide information on how current photosynthate allocated to the root system in perennial ryegrass (Lolium perenne L.) is distributed among individual roots at differing nodal positions. Mature single ryegrass tillers were transplanted in September 1993 to glass house pots and three months later four of the plants were supplied with 14CO2. Individual roots from these radioactively-labeled plants were identified according to their nodal position on the tiller axis and amount of radiocarbon in each root quantified for root tip segments and for the remainder of the root axis. Similar plants were destructively …

The Analysis Of Dynamic Interaction In Legume Binary Mixture Under Controlled Conditions Of Irrigation And Clipping, M S. Vrahnakis, B Noitsakis, Z Koukoura

IGC Proceedings (1977-2023)

The objective of this study was to analyse the type of interference that occurred between the annual legume species, purple clover (Trifolium purpureum L.) and narrow leaved crimson clover (Trifolium angustifolium Loisel. ), growing in mixed conditions under two different watering regimes and two different clipping treatments. A replacement series experiment was conducted in pots placed in the field. The above ground biomass (gr/plant) were measured. The recently proposed Inverse Linear Model was implied in order to analyse the competitive interaction between the above species. The results suggest that Tr. purpureum was the superior competitor to Tr. angustifolium …

Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel

LSU Master's Theses

I aim to constrain the crustal thickness of the Sabine Block in the Sabine Uplift region of northwest Louisiana, using the frequency domain receiver function deconvolution technique followed by H-κ stacking. The passive margin on the southern edge of the North American continent experienced an active tectonic history, including the spreading events that led to the formation of the Gulf of Mexico. A previous study proposed the Sabine Block is a residual fragment of Proterozoic orogenic origin; however, its full extent and geometry are up for debate. It is now overlain by thick sedimentary sequences ranging from ~4-6 km deposited …

Assessing The Spatial Variability Of Soil Physical Properties Under A Corn Field In Kentucky, Usa, Sai Neela Kesumala

Scholars Week

Analyzing soil physical properties is crucial for advancing sustainable and precision agricultural practices in today's world. Sustainable agriculture emphasizes responsible resource utilization and preservation. Precision agriculture utilizes technology, data, and targeted decision-making to optimize resource usage and minimize environmental impacts. Assessing soil property variability aids in efficient input application, irrigation adjustment, nutrient runoff reduction, and fertilizer management. This approach prioritizes soil conservation, boosts sustainability, and supports long-term agricultural productivity. This study aimed to evaluate the spatial distribution of specific soil physical properties across the four border rows, central corn field area, and sod area. Seventy-two soil samples were collected from …

Quantification Of Belowground Biomass And Sediment Accretion In Mangroves Of Different Coastal Environmental Settings Of The Costa Rican Pacific Coast, Denise M. Poveda

LSU Master's Theses

The adaptation of intertidal ecosystems such as mangroves to anticipated accelerated relative sea level rise is dependent on net increase of sediment surface elevations and forest migration inland. Ecosystem models developed to simulate trajectories of ecosystem adaptations have determined that rates of soil formation are most sensitive to surface sediment (organic and inorganic) deposition and subsurface organic production by mangrove roots. Mangrove belowground biomass contributes to soil organic matter accumulation, while mangrove litter has minor contribution due to export and annual decay. In addition to belowground biomass production, inorganic sediment loading is also key contribution to soil formation and accretion. …

Applied Depositional Geosystems Of The Coos Bay Basin, Oregon: Organic Geochemistry, Maturation, Paleoenvironmental Reconstruction And Biostratigraphy Of The Coaledo Delta During The Middle Eocene Climatic Optimum (Meco), Allison K. Barbato

LSU Doctoral Dissertations

The Coos Bay Basin on the southwestern coast of Oregon is a forearc basin that contains exceptionally preserved Eocene to Miocene, tidal to wave-dominated, shallow deltaic to deep marine sediments of the Coaledo Delta. Coastal depositional environments are known to host source, reservoir, and seal rocks. Climate, topographic relief, and geographical position all play an important role in regional vegetation development and oceanic setting. This study assesses 84 outcrop and 12 core samples from Coos Bay for their organic geochemical characteristics and microfossil assemblage to provide source rock characterization information, organofacies descriptions, environmental reconstructions, and age control.

Results indicate the …

Beach Processes Controlling Erosional Hotspots And Their Influences On Beach Nourishment Performances: A Case Study Along West-Central Florida Barrier Island Beaches, Sophia Gutierrez

USF Tampa Graduate Theses and Dissertations

This study examines the long-term performance of repeated beach nourishment over an approximately 35-year period at two barrier islands, Sand Key and Treasure Island along the west-central Florida coast, USA. Five cycles of beach nourishment on Sand Key and six on Treasure Island were conducted during the study period. Three erosional hotspots were identified along a combined 14-km stretch of the nourished beach. The processes that cause the erosional hotspot were examined through numerical modeling of nearshore wave and current fields.

The most recent three nourishments since 2006 were monitored systematically by this study. Beach profiles were surveyed bimonthly to …

A Petrological Characterization Of The Iutzi Member Of Lucas Formation, Michigan Basin, Moira Burns

Honors Theses

It is thought that most Phanerozoic dolomites form via the replacement of precursor calcium carbonate [CaCO₃] with dolomite [CaMg(CO₃)₂] through a dissolution-precipitation reaction with a Mg-bearing fluid. Although this may be widely accepted, the timing, conditions, settings, and mechanisms associated with the dolomitization process are still strongly debated, resulting in the proposal of various dolomitization models. The association between evaporite minerals and dolomite in the rock record is common and has led many to propose a model genetically associating evaporative fluids and dolomitization. The evaporative model posits as marine fluids evaporate and become more …

Estimation Of Useful-Stage Energy Returns On Investment For Fossil Fuels And Implications For Renewable Energy Systems, Emmanuel Aramendia, Paul E. Brockway, Peter G. Taylor, Jonathan B. Norman, Matthew Kuperus Heun, Zeke Marshall

University Faculty Publications and Creative Works

The net energy implications of the energy transition have so far been analysed at best at the final energy stage. Here we argue that expanding the analysis to the useful stage is crucial. We estimate fossil fuelsʼ useful-stage energy returns on investment (EROIs) over the period 1971–2020, globally and nationally, and disaggregate EROIs by end use. We find that fossil fuelsʼ useful-stage EROIs (~3.5:1) are considerably lower than at the final stage (~8.5:1), due to low final-to-useful efficiencies. Further, we estimate the final-stage EROI for which electricity-yielding renewable energy would deliver the same net useful energy as fossil fuels (EROI …

Festival Of Research Abstracts, Spring 2024, College Of Science And Mathematics, Wright State University

Festival of Research

The collection of abstracts accepted for the Spring 2024 Festival of Research hosted by the Wright State University College of Science and Mathematics.

Paradox Lost: Wide Gape In The Ordovician Brachiopod Rafinesquina Explains How Unattached Filter-Feeding Strophomenoids Thrived On Muddy Substrates, Benjamin F. Dattilo, Rebecca L. Freeman, Kyle Hartshorn, David Peterman, Aaron Morse, David L. Meyer, Lindsay G. Dougan, James W. Hagadorn

Earth and Environmental Sciences Faculty Publications

Strophomenoid brachiopods had thin, concavo-convex shells, were ubiquitous colonizers of Palaeozoic muddy seafloors, and are hypothesized to have filter-fed in a concave-upward orientation. This orientation would elevate their line of commissure out of potentially lethal lophophore-clogging mud. The paradox is that epi- biont distributions on strophomenoids support a convex-upward life position, as do studies of strophome- noid stability and trace fossils formed by strophomenoid sediment-clearing. A premise of the concave-upward orientation hypothesis is a narrow gape, which causes narrow, high velocity inhalant currents, leaving strophomenoids vul- nerable to sediment entrainment. Herein we investigate the gape angle of Rafinesquina using serial …

Consumer Preferences For Wood-Pellet-Based Green Pricing Programs In The Eastern United States, Sydney Oluoch, Pankaj Lal, Andres Susaeta, Meghann Smith, Bernabas Wolde

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Co-firing wood pellets with coal is an attractive alternative energy generation method with economic, social, and environmental benefits for the US energy generation sector. One way to sustainably use wood pellets for co-firing is to create consumer-supported green pricing programs (GPPs). Our study surveyed residents of five states (Alabama, New Jersey, New York, Pennsylvania, and Virginia) to investigate preferences for the attributes of a hypothetical GPP. The study applied the Best Worst Choice method, which employs the Best Worst Scaling (BWS) and binary choice (BC) task. The BWS analysis showed that residents of all five states most value the flexibility …

Evaluating The Role Of Titanomagnetite In Bubble Nucleation: Rock Magnetic Detection And Characterization Of Nanolites And Ultra-Nanolites In Rhyolite Pumice And Obsidian From Glass Mountain, California, Stefanie Brachfeld, Kelly N. Mccartney, Julia E. Hammer, Thomas Shea, Thomas Giachetti

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

We document the presence, composition, and number density (TND) of titanomagnetite nanolites and ultra-nanolites in aphyric rhyolitic pumice, obsidian, and vesicular obsidian from the 1060 CE Glass Mountain volcanic eruption of Medicine Lake Volcano, California, using magnetic methods. Curie temperatures indicate compositions of Fe2.40Ti0.60O4 to Fe3O4. Rock-magnetic parameters sensitive to domain state, which is dependent on grain volume, indicate a range of particle sizes spanning superparamagnetic (< 50–80 nm) to multidomain (>10 μm) particles. Cylindrical cores drilled from the centers of individual pumice clasts display anisotropy of magnetic susceptibility with prolate fabrics, with the highest degree of anisotropy coinciding with the highest vesicularity. Fabrics …

Evaluating The Role Of Titanomagnetite In Bubble Nucleation: Novel Applications Of Low Temperature Magnetic Analysis And Textural Characterization Of Rhyolite Pumice And Obsidian From Glass Mountain, California, Kelly N. Mccartney, Julia E. Hammer, Thomas Shea, Stefanie Brachfeld, Thomas Giachetti

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Nucleation of H2O vapor bubbles in magma requires surpassing a chemical supersaturation threshold via decompression. The threshold is minimized in the presence of a nucleation substrate (heterogeneous nucleation, < 50 MPa), and maximized when no nucleation substrate is present (homogeneous nucleation, >100 MPa). The existence of explosively erupted aphyric rhyolite magma staged from shallow (< 100 MPa) depths represents an apparent paradox that hints at the presence of a cryptic nucleation substrate. In a pair of studies focusing on Glass Mountain eruptive units from Medicine Lake, California, we characterize titanomagnetite nanolites and ultrananolites in pumice, obsidian, and vesicular obsidian (Brachfeld et al., 2024, https://doi.org/10.1029/2023GC011336), calculate titanomagnetite crystal number densities, and compare titanomagnetite abundance with the physical properties of pumice to evaluate hypotheses on the timing of titanomagnetite crystallization. Titanomagnetite crystals with grain sizes of approximately 3–33 nm are identified in pumice samples from the thermal unblocking of low-temperature thermoremanent magnetization. The titanomagnetite number densities for pumice are 10¹⁸ to 10²⁰ m⁻³, comparable to number densities in pumice and obsidian obtained from room temperature methods (Brachfeld et al., 2024, https://doi.org/10.1029/2023GC011336). This range exceeds reported bubble number densities (BND) within the pumice from the same eruptive units (average BND ∼4 × 10¹⁴ m⁻³). The similar abundances of nm-scale titanomagnetite crystals in …

Hydroclimatic Trends And Streamflow Response To Recent Climate Change: An Application Of Discrete Wavelet Transform And Hydrological Modeling In The Passaic River Basin, New Jersey, Usa, Felix Oteng Mensah, Clement Aga Alo, Duke Ophori

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The exigency of the current climate crisis demands a more comprehensive approach to addressing location-specific climate impacts. In the Passaic River Basin (PRB), two bodies of research—hydroclimatic trend detection and hydrological modeling—have been conducted with the aim of revealing the basin’s hydroclimate patterns as well as the hydrologic response to recent climate change. In a rather novel application of the wavelet transform tool, we sidelined the frequently used Mann–Kendal (MK) trend test, to identify the hidden monotonic trends in the inherently noisy hydroclimatic data. By this approach, the use of MK trend test directly on the raw data, whose results …

Joint Environmental And Social Benefits From Diversified Agriculture, Laura Vang Rasmussen, Ingo Grass

Earth and Environmental Sciences Faculty Publications

Agricultural simplification continues to expand at the expense of more diverse forms of agriculture. This simplification, for example, in the form of intensively managed monocultures, poses a risk to keeping the world within safe and just Earth system boundaries. Here, we estimated how agricultural diversification simultaneously affects social and environmental outcomes. Drawing from 24 studies in 11 countries across 2655 farms, we show how five diversification strategies focusing on livestock, crops, soils, noncrop plantings, and water conservation benefit social (e.g., human well-being, yields, and food security) and environmental (e.g., biodiversity, ecosystem services, and reduced environmental externalities) outcomes. We found that …

Unearthing The Past: A Comprehensive Study Of Natural And Anthropogenic Changes At An Archaeological Site Through Hydrogeologic Connectivity Utilizing Gis, Mehlich Ii Phosphorus Extractant, And Ph, Dana L. F. Herren

Theses

This thesis aims to thoroughly analyze the Mehlich II Phosphorus Extractant and pH levels at the Bains Gap Village Site in Anniston, AL., while examining the impact of various environmental factors and human activities on them. Phosphorus is often used in archaeology as an indicator of human activity. Soil core samples were collected to analyze anomalies in phosphorus levels.

To establish any relationships, phosphorus and pH levels from soil cores were correlated with findings from past excavation units and features. The potential effects of hydrogeologic connectivity on soil phosphorus and pH levels were investigated. Geospatial technologies were used to manage …

Tungsten Stable Isotope Composition Of The Upper Continental Crust, Sarah E. Mazza, Richard M. Gaschnig, Roberta L. Rudnick, Thorsten Kleine

Geosciences: Faculty Publications

Tungsten (W) stable isotope data for twenty-four composites made from the fine-grained matrix of glacial diamictites, deposited between the Mesoarchean and the Paleozoic, as well as two Archean tonalite-trondhjemite-granodiorites (TTG) are used to refine the W isotope compositions (expressed as δ186W deviations from the NIST 3163 W standard) of the upper continental crust (UCC). To do this we evaluate W isotope fractionation in the diamictites as the result of both magmatic and low-temperature processes. The δ186W values of the diamictites are heterogeneous (0.017 ± 0.011 ‰, 2SE to 0.182 ± 0.007 ‰, 2SE), encompassing the range of previously published values …

Paleozoic Evolution Of The Yukon-Tanana Terrane Of The North American Cordillera, Nw British Columbia, R. Soucy La Roche, A. Zagorevski, N. L. Joyce, J. L. Crowley

Geosciences Faculty Publications and Presentations

The origins and primary relationships between tectono-stratigraphic units are fundamental to the terrane concept in accretionary orogens, but they are challenging to assess in metamorphic terranes. In NW British Columbia, three tectonically bounded metamorphic suites of the Yukon-Tanana terrane formed in distinct tectonic settings, based on high-spatial-resolution geochronology and immobile trace-element geochemistry. The Florence Range suite comprises late Neoproterozoic or younger to pre–latest Devonian metasedimentary rocks derived from continental crust, 360 ± 4 Ma calc-alkaline intermediate orthogneiss, and 357 ± 4 Ma amphibolite with oceanic-island basalt composition, consistent with rifting of a continental margin. The detrital signature is dominated by …

What Soil Is Worth: A Cost-Benefit Framework Analysis Of Syntropic Farming, Aubrey Kettley

Independent Study Project (ISP) Collection

Syntropic farming, a type of regenerative agriculture, models its farming system after a forest. This type of farming prioritizes soil health while also providing a varied yield of crops. Because it is a fairly new system globally, little research has been done on the economic impacts of syntropic farming, and therefore the feasibility of scaling up regenerative systems like this. This study aims to analyze the economic feasibility of this system through a literature review and a cost-benefit analysis framework. The results highlight the applicability, environmental advantage and economic feasibility of the system. Based on the presented framework, the short …

How Can Morocco’S Crisis Management And Disaster Response Be Optimized? Lessons From The Al Haouz Earthquake Response, Clara Normand

Independent Study Project (ISP) Collection

Morocco’s disaster management strategy has evolved in reaction to historical crises. On September 8th, 2023, the Al Haouz region of Morocco was struck by a 7.2 magnitude earthquake. The area was especially vulnerable to such a disaster due to its underdeveloped infrastructure, remote location, and lack of services. As the last phase of the disaster management cycle is unfolding, seven months after the earthquake, this research assesses the successes and challenges of the response and establishes areas of improvement to implement in national policies to optimize future crisis management across all four stages of the disaster management cycle.

Impacts Of Gas Flaring On Soil Quality In The Ecuadorian Amazon: Measuring Gas Flare Effects On Soils At Comparative Distances In Loma Del Tigre, Orellana, Francesca Lopresti

Independent Study Project (ISP) Collection

Gas flaring, the process of burning off the natural gas excreted during petroleum extraction, has recently been the source of public outcry, citing degraded public and environmental health caused by constant flaring near populated centers. While extensive research has been done on the environmental and health impacts of gas flaring, regionally specific research to the Ecuadorian Amazon is lacking. It is crucial that updated research in this region is produced to inform regulations that have the potential to minimize the physical, environmental, and economic impact of the petroleum industry on nearby, under-resourced, and marginalized communities. While air quality surrounding gas …

Uncovering Chimborazo’S Catchments: Insights Into The Fluvial Network, Stream Characteristics, And Hydrological Patterns In Reserva De Producción De Fauna Chimborazo, Ecuador, Julia L. Schwartz

Independent Study Project (ISP) Collection

Andean headwater streams play a crucial role in the provisioning of ecosystem services and supplying water to downstream communities. This study sought to analyze trends in hydrological patterns in the páramo of the southwestern aspect of Volcán Chimborazo in central Ecuador, as well as to provide a more complete survey of the fluvial network given the lack of existing data and its importance in water resource management. Measurements of stream elevation, grade of slope, water temperature, pH, width, depth, turbidity, velocity, and discharge, as well as geomorphological characteristics of catchments such as slope and permeability, were taken at 19 sites …

Subsurface Mapping Of Intra-Arbuckle Shale In North-West Kansas Using Well Log Data, Cole M. Denny

SACAD: Scholarly Activities

The aim of this research was to enhance knowledge of Intra-Arbuckle Shale (IAS) distribution and structure through new maps, cross sections, and well log correlations. Understanding the shale(s) ultimately advances the discernment of complex Arbuckle reservoirs that are critical to the Kansas petroleum industry. IAS has been intercepted by oil wells throughout Kansas, but this study focuses on their presence in portions of Ellis, Rooks, Graham, and Trego counties. To study the distribution and structure of IAS, data from micro-resistivity and gamma ray well logs were collected from more than three hundred Arbuckle oil and gas wells. On each well …

Transport Of Multi-Phase Multi-Component Fluids In The Shallow Subsurface Influenced By Soil And Surface Boundary Conditions: Experimental And Numerical Study With Application To Natural Gas Leakage, Navodi Jayarathne

Civil and Environmental Engineering Theses and Dissertations

With the increased use of Natural Gas (NG) as a source of fuel, underground leak-related events are increasingly reported, and some are fatal. Subsurface migration and development up to flammable limits are highly dependent on leak characteristics, soil, atmospheric variables, and other surface and subsurface structural complexities. Although few studies have characterized the transient behavior of leaked NG in the shallow subsurface, the underlying mechanisms and their interactions are not well understood, which prevents prediction of the impact of environmental and operating conditions on gas migration. The study conducted a series of field scale-controlled release experiments and numerical simulations to …

Beavers, Hydrology, And Wapato: A Baseline For Monitoring Franz Lake National Wildlife Refuge, Justine Casebolt

Environmental Science and Management Professional Master's Project Reports

Located in the lower Columbia River floodplain, Franz Lake National Wildlife Refuge is a unique landscape with a complex land use history. For thousands of years, Indigenous tribes lived on this land. In the early 1990s, U.S. Fish and Wildlife Service acquired the land, after it was identified as a mitigation site following the construction of the Bonneville Lock and Dam. Franz Lake Refuge was once known for its prevalent Wapato (Sagittaria latifolia) population, an emergent plant with edible tubers and an important food source for Indigenous people. With specific growth requirements and hydrologic conditions for germination and …