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Satellite-Based Estimation Of Seasonal Surface Water Change And Its Relationship To Climate Variability In A Tropical Open Basin Lake, Osnar Mondragon Grios

Graduate Theses and Dissertations

This study explores the spatiotemporal dynamics of climate variability and water surface area in Lake Nicaragua, one of the largest tropical lakes on Earth. The significance of this study lies in its potential to provide valuable insights into the hydroclimatic patterns and water availability, vital for Nicaragua’s water supply. Monthly and seasonal time series of precipitation, land surface temperature, and evapotranspiration (ET), acquired from the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) and Moderate Resolution Imaging Spectroradiometer (MODIS), were analyzed in Google Earth Engine using a non-parametric Mann-Kendall trend test and Sen's slope. The second aim of this …

The Tidal Prism, Viable Eelgrass Habitat, And The Effects Of Sea Level Rise In Morro Bay, Kaden A. Caliendo

Master's Theses

The tidal prism, or the volume of water exchanged from the sea to an estuary from mean low to mean high tide, influences system hydrodynamics and ecological functioning. Since 1884, the tidal prism in Morro Bay, California has been estimated to be decreasing over time due to sedimentation from upstream practices. What is the current tidal prism in Morro Bay and how will that change with sea level rise? How will eelgrass respond to rising sea levels?

For this study, inexpensive tidal gauges were deployed at four locations in Morro Bay from March to August 2023 to measure spatially varying …

Co2 Storage Capacity And Injectivity Of Stacked Carbonates Of The Pennsylvanian And Permian In Western Nebraska, Lateef Lawal

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Geological carbon storage (GCS) is a critical aspect of carbon capture and storage (CCS) in which captured CO₂ from power plants and industrial processes is injected and stored securely underground. Potential subsurface rock formations include saline aquifers, depleted oil and gas reservoirs, unmineable coal seams and volcanic rocks. GCS technology has been proven in the United States and many other parts of the world as a net-zero carbon emission strategy to mitigate the current climate crisis of our planet. Unlike other states such as Wyoming, GCS projects are still in the early phases in Nebraska. The goal of this …

Ecological Impacts Of Restoring Fire-Grazing Interaction In Sandhills Prairie Through Patch-Burn Grazing, Nolan P. Sipe

School of Natural Resources: Dissertations, Theses, and Student Research

A Collaborative Adaptive Management (CAM) Project was started at the University of Nebraska in 2020 to address some of the key uncertainties related to the management of grasslands in the Nebraska Sandhills through stakeholder driven experiments and the adaptive management cycle. Patch-burn grazing was selected by CAM as a management tool to generate heterogeneity across the landscape and promote biodiversity while balancing economic and ecological trade-offs. The patch-burn grazing system was implemented with controlled burns in May of 2022 and March of 2023. Other parties in CAM will be examining the impact that patch-burn grazing has on forage and livestock …

Human Dimensions Of Woody Encroachment Management In Nebraska, Emily Rowen

School of Natural Resources: Dissertations, Theses, and Student Research

Woody plant encroachment (WPE) is a social-ecological problem that will challenge conservation professionals and agricultural producers to adapt their management strategies. This research first examined WPE from the perspective of individual conservation professionals through an online survey. Conservation professionals’ attitudes about adaptation to vegetation transitions, such as WPE, were of interest because these attitudes are one measure of how prepared this group is to respond to WPE. Hypothesized predictors of adaptation attitude were tested through linear regression modeling. These predictors included ecological change, observation of WPE, or risk perception. It was found that risk perception was the strongest predictor of …

The Influence Of Invasive Species On Fishers’ Satisfactions, Caroline M. Laplante

School of Natural Resources: Dissertations, Theses, and Student Research

Invasives species are prevalent and widespread in North America. Outdoor recreational activities, such as fishing, introduce a point in which humans may interact with invasive species and have to adapt their own behaviors. Bigheaded carp in the Missouri River below Gavin’s Point Dam are a group of invasive fish species that were thought to be negatively relating to recreational fishers’ satisfactions. Using a content analysis and an importance-grid, we conclude that invasive species do not strongly relate to recreational paddlefish fishers’ satisfactions. Paddlefish fishers represent a small sub-set of recreational fishers in Nebraska and South Dakota. The content analysis revealed …

In Situ Water Sensing Systems: Research On Advancements In Environmental Monitoring, Abigail Seibel

Honors Program: Senior Projects (Public)

In this work, two sensing systems were researched in order to improve in situ environmental monitoring. The first is a pH and Total Alkalinity sensor used to determine these characteristics of sea water. I explored the facets of this sensor over a 7-week internship with Dr. Ellen Briggs in her lab in summer of 2023. The second is a more holistic sensing system that reads temperature, turbidity, and pressure used for studying environmental characteristics of Alaskan bever ponds. Both systems were developed in close collaboration with scientists who are collecting data to better understand the impacts of climate change. Better …

Estimating Financial And Environmental Risk: Some New Developments And Comparison Study., Fnu Kamronnaher

All Dissertations

This dissertation delves into the concept of risk, specifically focusing on two prominent categories: financial risk and environmental risk.

Financial risk is the probability of unfavorable outcomes of an investment while environmental risk refers to the possible harm to the environment resulting from extreme weather events. More specifically, risk is the high (low) quantiles of the distribution of variables of interest. \\ To quantify and assess uncertainties in financial and environmental risk, robust and reliable methodologies are needed. The aim of this dissertation is to develop some risk assessment methods and compare them with the widely used methodologies in both …

Wavelet Compression As An Observational Operator In Data Assimilation Systems For Sea Surface Temperature, Bradley J. Sciacca

LSU New Orleans Theses and Dissertations

The ocean remains severely under-observed, in part due to its sheer size. Containing nearly billion of water with most of the subsurface being invisible because water is extremely difficult to penetrate using electromagnetic radiation, as is typically used by satellite measuring instruments. For this reason, most observations of the ocean have very low spatial-temporal coverage to get a broad capture of the ocean’s features. However, recent “dense but patchy” data have increased the availability of high-resolution – low spatial coverage observations. These novel data sets have motivated research into multi-scale data assimilation methods. Here, we demonstrate a new assimilation approach …

Coastal Wetland Restoration Through The Lens Of Odum's Theory Of Ecosystem Development, Friedrich W. Keppeler, Annette S. Engel, Linda M. Hooper-Bùi, Paola C. López-Duarte, Charles W. Martin, Jill A. Olin, Katelyn J. Lamb, Michael J. Polito, Nancy N. Rabalais, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Advancing ecological restoration assessments requires a more detailed consideration of species interactions and ecosystem processes. Most restoration projects rely on a few metrics not always directly linked with ecological theory. Here, we used Odum's theory of ecosystem development to assess and compare the ecosystem structure and services of created marshes (4–6 years old) with preexisting, reference marshes in a brackish water region of the Mississippi River Delta. We built ecosystem models for created and reference marshes that integrated large datasets of stomach contents, stable isotopes, and taxa abundances. Despite strong resemblance in community structure, created marshes were at an earlier …

Enhancing Urban Water Quality Through Biological-Chemical Treatment: Aquatic Macroinvertebrate Community And Temporal Chlorophyll-A Response, Matthew Chaffee

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

With a growing human population, urbanization is impeding a plethora of natural waterways. Of these, urban ponds play a vital role in nutrient sequestration, flood prevention, and habitat sanctuaries. However, nutrient loading can reduce habitat effectiveness and promote harmful algae blooms. To reduce internal nutrient loads, a biological-chemical treatment strategy consisting of floating treatment wetlands (FTWs) and lanthanum were applied to two urban retention ponds, Densmore and Wilderness Ridge Ponds. To measure effectiveness, chlorophyll-a samples were collected and correlated with Sentinel-2. A novel band algorithm termed 3BR1 produced a strong correlation (R² = 0.72) to physical chlorophyll-a …

Electrolysis Degradation Of Cyanuric Acid In Wastewater At Cu/Go Cathodes, Chioma Chinwe Nwakanobi

Theses and Dissertations

This work evaluates the development of electrochemical processes for the oxidative degradation of persistent organic chemicals in waste waters, specifically the oxidation of cyanuric acid in the presence of NaCl at Cu/GO cathodes and Ti anodes. The experiment used a graphene oxide doped copper mesh cathode to examine different concentrations of cyanuric acid (30 mg/L, 40 mg/L, and 50 mg/L) and various concentrations of NaCl electrolyte (0.007mol/L, 0.03mol/L, 0.07mol/L, 0.1mol/L, and 0.2mol/L). In addition, the effect of pH (2, 4, 6, and 8), and applied current (0.200A, 0.150A and 0.100A) were studied. The Cu/GO electrode played a central role in …

Accelerated Evolution Of Sars-Cov-2 In Free-Ranging White-Tailed Deer, Dillon S. Mcbride, Sofya K. Garushyants, John Franks, Andrew F. Magee, Steven H. Overend, Devra Huey, Amanda M. Williams, Seth A. Faith, Ahmed Kandeil, Sanja Trifkovic, Lance Miller, Trushar Jeevan, Anami Patel, Jacqueline M. Nolting, Michael J. Tonkovich, J. Tyler Genders, Andrew J. Montoney, Kevin Kasnyik, Timothy J. Linder, Sarah N. Bevins, Julianna B. Lenoch, Jeffrey C. Chandler, Thomas J. Deliberto, Eugene V. Koonin, Marc A. Suchard, Philippe Lemey, Richard J. Webby, Martha I. Nelson, Andrew S. Bowman

United States Department of Agriculture Wildlife Services: Staff Publications

The zoonotic origin of the COVID-19 pandemic virus highlights the need to fill the vast gaps in our knowledge of SARS-CoV-2 ecology and evolution in non-human hosts. Here, we detected that SARS-CoV-2 was introduced from humans into white-tailed deer more than 30 times in Ohio, USA during November 2021-March 2022. Subsequently, deer-to-deer transmission persisted for 2–8 months, disseminating across hundreds of kilometers. Newly developed Bayesian phylogenetic methods quantified how SARS-CoV-2 evolution is not only three-times faster in white-tailed deer compared to the rate observed in humans but also driven by different mutational biases and selection pressures. The long-term effect of …

Analysis Of Mitochondrial Dna Sequence Data Demonstrates That Monophyly Of Myotis Occultus Is Complicated By Greater Sampling Of Myotis Lucifugus, Jeffrey M. Lorch, Daniel R. Taylor, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Abstract

The validity of Myotis occultus as a species unique from Myotis lucifugus has been a source of debate. Most recently, many authorities treat M. occultus as a distinct species, at least in part because a previous study showed that M. occultus and M. l. carissima (the subspecies that occurs in closest geographic proximity to M. occultus) form separate monophyletic clades based on sequences of two mitochondrial genes (cytochrome-b [cytb] and cytochrome oxidase subunit II [COII]). We re-evaluated the phylogenetic relationship between M. occultus and M. lucifugus based on mitochondrial sequences …

Through The Lens Of A Naturalist: How Learning About Nature Promotes Nature Connectedness Via Awe, Shu Tian Ng, Angela K. Y. Leung, Sarah Hian May Chan

Research Collection School of Social Sciences

Environmental educators stress the importance of engaging with the wonders of the Earth in promoting nature connectedness. However, it remains unclear if learning about nature has an incremental effect beyond mere exposure to nature and what psychological mechanism can explain such a learning effect if it exists. To fill this gap, we propose a mediation model in which learning about nature promotes a sense of awe—a self-transcendent emotion associated with the recognition of vastness in nature. A sense of awe, in turn, promotes nature connectedness. Study 1 employed a cross-sectional survey and offered preliminary support for the proposed model, with …

Niobate Nanosheet Catalysts For Cationic Dye Intercalation And Solar-Driven Water Photolysis, Cassandra Idona Monárrez-Grendahl

Open Access Theses & Dissertations

With the goal of creating efficient visible light photocatalysts for water photolysis, in this work we are exploring the synthesis of new porous oxide materials derived from potassium triniobate (KNb3O8) and titanium niobium oxide (KTiNbO5), which are layered wide band gap semiconductors. Generating hydrogen via direct water photolysis holds promise as a way to lower the cost of hydrogen gas production so it can be used as a renewable and clean alternative fuel. My group has demonstrated that layered semiconductor materials have the potential to enable the synthesis of new types of photocatalyst composites with customizable characteristics. In this work, …

Evaluation Of Evapotranspiration Estimates Using An Existing Hybrid Machine Learning Model In A Natural And A Managed Dryland Site, Katya Esquivel Herrera

Open Access Theses & Dissertations

Evapotranspiration (ET) is a critical component of the hydrologic cycle, encompassing both evaporative water loss from surfaces and transpiration through plant stomata. The environmental factors influencing ET include water and energy availability, atmospheric capacity for water uptake, and various meteorological variables. ET serves as a unique climate variable linking water, energy, and carbon cycles. In agroecosystems, accurate ET quantification is vital for optimizing water use efficiency, irrigation management, and crop yield. Traditional methods for ET estimation involve direct measurements and indirect models, with both presenting limitations.

Recent years have witnessed the integration of remote sensing and machine learning (ML) algorithms …

The Evaluation Of Feed Additives On Reducing Enteric Methane Production From Cattle, Reba L. Colin

Department of Animal Science: Dissertations, Theses, and Student Research

Environmental sustainability can be positively impacted by the inclusion of feed additives to reduce enteric methane production from cattle. Methane production can be affected by feed additives that either alter the rumen environment or act as methanogenesis inhibitors. A reduction in methane from cattle can contribute to meeting carbon neutrality.

A metabolism study was conducted to evaluate Alga 1.0, a product containing bromoform, fed to cattle to evaluate the effects on gas emissions. Treatments were (0, 69, or 103 g/d Alga 1.0) fed in a corn-based diet. Headbox-style indirect calorimeters were used to measure gas emissions. Feeding Alga 1.0 linearly …

Beyond Corporate Greenwashing: Discourse Of A 'Just' Electric Energy Transition Materialized At The Thacker Pass Lithium Mine, Laekyn Kelley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Thacker Pass in Northern Nevada is a rich desert ecosystem with spiritual significance to local Indigenous peoples, and it is also the site for what will be, for now, the United States’ largest open-pit lithium mine. Lithium is one mineral constituent of electric batteries which are essential to current U.S. electric energy transition policy, a transition which policymakers and other public groups have called on to be done in a way which is just. However, what exactly a just electric energy transition looks like in places like Thacker Pass is under continued negotiation in theoretical and practical senses. Existing research …

Measuring The Lengths Of Sperm Whales Of The Northern Gulf Of Mexico By Wavelet Analysis Of Their Usual Clicks, George Drouant

LSU New Orleans Theses and Dissertations

Abstract

Acoustic recordings of underwater sounds produced by marine mammals present an attractive alternative to costly and logistically complex ship based visual surveys for collecting population data for various species.

The first reported use of underwater acoustic recordings in the long-term monitoring of sperm whale populations was by Ackleh et al. (Ackleh et al., 2012). The paper describes counting sperm whale clicks at different locations to track population changes over time.

Analysis of sperm whale clicks offers additional insight into sperm whale populations. The echo location clicks (usual clicks) of sperm whales can be used to give an estimate of …

Globally-Distributed Microbial Eukaryotes Exhibit Endemism At Deep-Sea Hydrothermal Vents, Sarah K. Hu, Amy R. Smith, Rika E. Anderson, Sean P. Sylva, Michael Setzer, Maria Steadmon, Kiana L. Frank, Eric W. Chan, Darlene S. S. Lim, John A. Breier

School of Earth, Environmental, & Marine Sciences Faculty Publications

Single-celled microbial eukaryotes inhabit deep-sea hydrothermal vent environments and play critical ecological roles in the vent-associated microbial food web. 18S rRNA amplicon sequencing of diffuse venting fluids from four geographically- and geochemically-distinct hydrothermal vent fields was applied to investigate community diversity patterns among protistan assemblages. The four vent fields include Axial Seamount at the Juan de Fuca Ridge, Sea Cliff and Apollo at the Gorda Ridge, all in the NE Pacific Ocean, and Piccard and Von Damm at the Mid-Cayman Rise in the Caribbean Sea. We describe species diversity patterns with respect to hydrothermal vent field and sample type, identify …

Draft Final Bpsou 2023 Uncontrolled Surface Flow Area Soil Characterization Quality Assurance Project Plan (Qapp), Woodard & Curran

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Butte Priority Soils Operable Unit Uncontrolled Surface Flow Areas Draft Remedial Design Work Plan (Rdwp), Woodard & Curran

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Uncertainty In Streamflow Measurements Significantly Impacts Estimates Of Downstream Nitrate Export, Shannon L. Speir, C. Nathan Jones, Arial J. Shogren, Carla L. Atkinson

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Across watershed science, two key variables emerge–streamflow and solute concentration–which serve as the basis for efforts ranging from basic watershed biogeochemistry research to policy decisions surrounding watershed management. However, we rarely account for how error in discharge (Q) impacts estimates of downstream nutrient loading. Here, we examined the impact of uncertainty in streamflow measurements on estimates of downstream nitrate export using publicly available data from the U.S. Geological Survey (USGS). We characterized how uncertainty in stage-discharge relationships impacts annual flux estimates across 70 USGS gages. Our results indicate the interquartile range of relative error in Q was 33% across these …

A Control Study Analysis Application Of Unoccupied Aerial Systems (Drones) To Monitor Eutrophication, Chrystal Mata

Water Resources Science and Technology Theses and Graduate Research Reports (Archived)

Unmanned Aircraft systems (UAS) can offer a valuable perspective for detecting and monitoring for eutrophication in bodies of water by providing high-resolution images and data assignments for algal blooms and nutrient levels. Eutrophication, the process by which water bodies become enriched with nutrients, has emerged as a critical factor in evaluating and maintaining water quality. In this study, we use DJI Inspire Pro 1 equipped with a Zenmuse X3 camera, attached with a Parrot Sequoia multispectral sensor was used to in conjunction with algorithms to retrieve Chlorophyll parameters for monitoring eutrophication. Although water quality parameters such as pH, nitrate, phosphate, …

Multi-Objective Water Management In Idaho's Henrys Fork Watershed: Leveraging Reservoir Operation And Groundwater Pathways To Benefit Aquatic Habitat, Christina N. Morrisett

All Graduate Theses and Dissertations, Fall 2023 to Present

Multi-user water management is a challenging arena further complicated by climate change. This research is based in the Henrys Fork, Snake River, Idaho—an agricultural watershed that exemplifies those throughout the semi-arid American West. This dissertation uses an integrated approach that considers groundwater-river relationships, farm-scale decisions and basin-scale outcomes, upstream reservoir operation for downstream aquatic habitat, water rights, and collaborative stakeholder management to identify drought adaptation strategies accordingly.

Chapter 2 uses an interdisciplinary approach to quantify how improvements to irrigation efficiency at the farm-scale (i.e., converting from flood to sprinkler irrigation) can add up to affect hydrology at the landscape-scale and …

A Comprehensive Assessment Of Anthropogenic And Natural Sources And Sinks Of Australasia's Carbon Budget, Yohanna Villalobos, Josep G. Canadell, Elizabeth D. Keller, Peter R. Briggs, Beata Bukosa, Donna L. Giltrap, Ian Harman, Timothy W. Hilton, Miko U. F. Kirschbaum, Ronny Lauerwald, Liyin L. Liang, Taylor Maavara, Sara E. Mikaloff-Fletcher, Peter J. Rayner, Laure Resplandy, Judith Rosentreter, Eva M. Metz, Oscar Serrano, Benjamin Smith

Research outputs 2022 to 2026

Regional carbon budget assessments attribute and track changes in carbon sources and sinks and support the development and monitoring the efficacy of climate policies. We present a comprehensive assessment of the natural and anthropogenic carbon (C-CO2) fluxes for Australasia as a whole, as well as for Australia and New Zealand individually, for the period from 2010 to 2019, using two approaches: bottom-up methods that integrate flux estimates from land-surface models, data-driven models, and inventory estimates; and top-down atmospheric inversions based on satellite and in situ measurements. Our bottom-up decadal assessment suggests that Australasia's net carbon balance was close to carbon …

Vegetated Coastal Ecosystems In The Southwestern Atlantic Ocean Are An Unexploited Opportunity For Climate Change Mitigation, Vanessa Hatje, Margareth Copertino, Vinicius F. Patire, Ximena Ovando, Josiah Ogbuka, Beverly J. Johnson, Hilary Kennedy, Pere Masque, Joel C. Creed

Research outputs 2022 to 2026

Vegetated coastal ecosystems (mangroves, seagrasses, and saltmarshes, often called Blue Carbon ecosystems) store large carbon stocks. However, their regional carbon inventories, sequestration rates, and potential as natural climate change mitigation strategies are poorly constrained. Here, we systematically review organic carbon storage and accumulation rates in vegetated coastal ecosystems across the Central and Southwestern Atlantic, extending from Guyana (08.28°N) to Argentina (55.14°S). We estimate that 0.4 Pg organic carbon is stored in the region, which is approximately 2-5% of global carbon stores in coastal vegetated systems, and that they accumulate 0.5 to 3.9 Tg carbon annually. By ecosystem type, mangroves have …

Inundated Vegetation Response To Ongoing Restoration And Its Impacts On Fish Community Structure, Emmanuel J. May

All Graduate Theses and Dissertations, Fall 2023 to Present

Shallow lake ecosystems and their associated wetland habitats globally are subject to non-native species introductions, nutrient loading, and water level fluctuations, each of which can decrease vegetated habitat availability, exposing vulnerable native aquatic species to predation. Managers are frequently tasked with mitigating native species declines by restoring vegetation considered crucial for their survival. However, restoring vegetation can be challenging in the presence of multiple stressors, requiring managers to assess the relative importance of the different stressors limiting vegetation recovery.

Utah Lake is a large shallow lake subject to multiple stressors and has shifted from a mesotrophic lake with abundant aquatic …

Ecology And Management Of Dyer's Woad (Isatis Tinctoria) In Northern Utah, Erin Marie Hettinger

All Graduate Theses and Dissertations, Fall 2023 to Present

Dyer’s woad (Isatis tinctoria L.) is a non-native forb that continues to threaten natural areas throughout Northern Utah and much of the Intermountain West. Once introduced, dyer’s woad can become extremely invasive, decreasing forage quality, and displacing native species. While dyer’s woad is found throughout much of Northern Utah, its range in other states remains limited. If promptly managed, control success in these areas will be much higher and populations may be kept at bay before ecological damage becomes severe.

This project tested the ability of dyer’s woad seedlings to compete with common rangeland grasslands at varied densities as …