Digital Commons Network^™

Major Axes Of Variation In Tree Demography Across Global Forests, Melina De Souza Leite, Sean M. Mcmahon, Paulo Inácio Prado, Stuart J. Davies, Alexandre Adalardo De Oliveira, Hannes P. De Deurwaerder, Salomón Aguilar, Kristina J. Anderson-Teixeira, Nurfarah Aqilah, Norman A. Bourg, Warren Y. Brockelman, Nicolas Castaño, Chia-Hao Chang-Yang, Yu-Yun Chen, George Chuyong, Keith Clay, Álvaro Duque, Sisira Ediriweera, Corneille E. N. Ewango, Gregory Gilbert, I. A. U. N. Gunatilleke, C. V. S. Gunatilleke, Robert Howe, Walter Huaraca Huasco, Akira Itoh, Daniel J. Johnson, David Kenfack, Kamil Král, Yao Tze Leong, James A. Lutz, Jean-Remy Makana, Yadvinder Malhi, William J. Mcshea, Mohizah Mohamad, Musalmah Nasardin, Anuttara Nathalang, Geoffrey Parker, Renan Parmigiani, Rolando Pérez, Richard P. Phillips, Pavel Šamonil, I-Fang Sun, Sylvester Tan, Duncan Thomas, Jill Thompson, María Uriarte, Amy Wolf, Jess Zimmerman, Daniel Zuleta, Marco D. Visser, Lisa Hülsmann

Wildland Resources Faculty Publications

The future trajectory of global forests is closely intertwined with tree demography, and a major fundamental goal in ecology is to understand the key mechanisms governing spatio-temporal patterns in tree population dynamics. While previous research has made substantial progress in identifying the mechanisms individually, their relative importance among forests remains unclear mainly due to practical limitations. One approach to overcome these limitations is to group mechanisms according to their shared effects on the variability of tree vital rates and quantify patterns therein. We developed a conceptual and statistical framework (variance partitioning of Bayesian multilevel models) that attributes the variability in …

Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) 2024 Draft Final Insufficiently Reclaimed Areas Quality Assurance Project Plan (Qapp) (Dated March 8, 2024), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Identifying High-Value Tactical Livestock Decisions On A Mixed Enterprise Farm In A Variable Environment, Michael Young, John Young, Ross S. Kingwell, Philip E. Vercoe

Animal production and livestock research articles

Context

Australia is renowned for its climate variation, featuring years with drought and years with floods, which result in significant production and profit variability. Accordingly, to maximise profitability, dryland farming systems need to be dynamically managed in response to unfolding weather conditions.

Aims

The aim of this study is to identify and quantify optimal tactical livestock management for different weather-years.

Methods

This study employed a whole-farm optimisation model to analyse a representative mixed enterprise farm located in the Great Southern region of Western Australia. Using this model, we investigated the economic significance of five key livestock management tactics. These included …

Glacier Lake Inventory And Lake Outburst Flood Hazard Assessment In Kanchenjunga Conservation Area, Nepal, Prabish Khadka Chhetri

Theses

This study presents a comprehensive assessment of glacial lakes and land surface temperature (LST) dynamics within the Kanchenjunga Conservation Area (KCA) from 2010 to 2023. The KCA holds significant ecological importance, serving as a critical habitat for diverse flora and fauna, while also playing a vital role in regional hydrological systems. Additionally, its stunning landscapes attract tourists and mountaineers from around the world, further emphasizing the need for understanding environmental changes within the area. Utilizing medium to high-resolution satellite imagery from PlanetScope for glacial mapping and Landsat for LST analysis, the research aimed to achieve two primary objectives: creating an …

Including Methane Emissions From Agricultural Ponds In National Greenhouse Gas Inventories, Martino E. Malerba, Tertius De Kluyver, Nicholas J. Wright, Odebiri Omosalewa, Peter I. Macreadie

Climate Science Research Articles

Agricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the …

Sustainable Service Trends In Restaurants, Suruchi Bhatt

School of Business

Being Sustainable is an essential milestone in the food industry. Companies form and fall because of consumers' reactions to the industry. The food industry and restaurants account for some of the highest Food Waste and Pollution, approximately 34% of the Global anthropogenic greenhouse gas emissions, including food production, processing, distribution, and consumption. (Crippa et al., 2021) In a sector like this, ensuring a complete understanding of sustainability in the industry is of utmost importance. However, the sheer relationship between the sustainable image, the prospect of sustainability, and the reality of implementing it may be far from reality. (Yuying-Huang, 2022)

Predicting The Effects Of Precipitation On Groundwater Contamination Near Capped And Uncapped Coal Ash Storage Facilities In Louisville, Kentucky., Daryl Jialiang Chen

Electronic Theses and Dissertations

This study examines the impact of rainfall event characteristics and water table elevations on arsenic and boron contamination in groundwater near two coal ash ponds in Louisville, Kentucky. Utilizing data from 2011 to 2019, the research focuses on both capped and uncapped ponds at Mill Creek and Cane Run sites, employing Threshold Analysis, Regularized Discriminant Analysis (RDA) and Random Forest (RF) to assess contamination levels in groundwater. Analysis shows that capped ponds generally exhibit reduced arsenic levels, though variations exist depending on the contaminant and site. Key predictors such as maximum precipitation and river height were identified, highlighting their significant …

Educational Influences On Environmental Perception: A Semester Analysis Of The New Ecological Paradigm Scale In Undergraduates, Zoe Zingler

Department of Environmental Studies: Undergraduate Student Theses

This study evaluated the impact of a geography course, GEOG 181: Global Environmental Issues, at the University of Nebraska-Lincoln on students’ endorsement of the New Ecological Paradigm (NEP) using a pre-course and post-course NEP scale survey. Analyzing paired responses (n = 40) through t-tests and z-scores, only four of 15 statements had statistically significant shifts observed for the entire sample. However, a targeted analysis of students initially possessing lower endorsement of the NEP—early deniers—revealed significant paradigm shifts post-course. While women initially showed stronger NEP endorsement, men demonstrated notable changes following the course towards endorsement of the NEP. Academic majors, whether …

Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Wastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4⋅6H2O), may provide a sustainable alternative to rapidly decreasing rock phosphate reserves. Struvite can be generated via chemical and/or electrochemical precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice cultivar (Gemini 214, RiceTec) grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)] in a P-deficient silt …

Barrier Removal Prioritization To Increase Climate Resiliency And Aquatic Connectivity For Communities In The Upper Susquehanna Basin, Cassandra Mae Davis

Legacy Theses & Dissertations (2009 - 2024)

The streams and rivers of the Upper Susquehanna Basin have been heavily modified over centuries through deforestation of nearshore areas and creation of physical barriers, such as dams and culverts. Dams and undersized culverts negatively affect aquatic organisms by modifying habitat conditions and restricting movement of these organisms. In addition, improperly maintained dams and undersized culverts can intensify flooding impacts and negatively affect water quality. A standardized method is needed to determine which barriers should be prioritized for assessment and potential replacement or removal based on multiple ecosystem and societal factors. The goal of this analysis was to have a …

Towards Sustainable Development: Civic Architecture As Material Banks, Kathleen O'Gara

Masters in Architecture Program: Theses

This thesis posed the question, “How can buildings be designed to be disassembled and reused to reduce construction and demolition waste and reduce our unsustainable reliance on raw materials?” Designing for disassembly and reuse has the potential to dramatically increase the life of building materials, thus decreasing construction and demolition waste relating to architecture. When designing with deconstruction and reuse in mind, designers must consider the next life of these materials. The thesis was further narrowed to push the adaptability of these materials by designing a structural kit of parts. The structure system is often seen as a stable and …

Effect Of Biomass Water Dynamics In Cosmic-Ray Neutron Sensor Observations: A Long-Term Analysis Of Maize–Soybean Rotation In Nebraska, Tanessa Morris

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

The precise measurement of soil water content (SWC) is crucial for effective water resource management. This study utilizes the Cosmic Ray Neutron Sensor (CRNS) for area-averaged SWC measurements, emphasizing the need to consider all hydrogen sources, including the time-variable ones like plant biomass and water content. Chapter 1 presents a background on soil moisture estimation, CRNS technology, and an overview of the study. It discusses various soil moisture measurement techniques, highlights the gap in knowledge addressed by CRNS technology, explains CRNS functionality and advancements, and outlines the study's motivations and methods.

Chapter 2 reports a study conducted near Mead, Nebraska, …

Landslide Susceptibility And Tree Ring Eccentricity Analysis Along Unstable Slopes Of The New River Watershed, Anderson And Morgan Counties, Tn, Megan Palmer

Electronic Theses and Dissertations

Landslides are mass movements that affect infrastructure across East Tennessee, causing problems for the Tennessee Department of Transportation (TDOT). An assessment of conditions and locations of unstable slopes can aid TDOT in infrastructure management. Landslide susceptibility was evaluated for Anderson and Morgan counties, TN, off State Route 116 in the New River watershed. Susceptibility maps used a landslide inventory and six factors: elevation, slope, geology, distance from stream, rainfall, and curvature, input in forest-based classification and logistic regression models. Additionally, affected trees along these unstable slopes in Anderson and Morgan counties were cored to analyze mass movement impacts on tree …

Examining The Relationship Between Manning's Roughness Coefficient And Stage, Henry Holtkamp

Biological and Agricultural Engineering Undergraduate Honors Theses

This paper uses LOESS regression to predict Manning's roughness coefficient to calculate flows in natural stream channels. Manning's roughness coefficient can introduce variability into Manning's equation, potentially destabilizing results. Utilizing LOESS to find n based on backcalculated n from collected discharge vs. stage information is the best way to acquire accurate Manning's roughness coefficient values at a variety of flows. Book values tend to drastically overestimate which can have wide-ranging implications for water allocation, flood management, maintaining environmental flows, and maintaining water quality.

Modification, Transport, And Sources Of Hydrocarbon Oxidation Products From Groundwater At Crude Oil And Diesel Spill Sites In Minnesota: Unveiling Common “Theems” Via Spectroscopy & Chromatography, Eduardo E. Turcios Valle

LSU New Orleans Theses and Dissertations

In this thesis, petroleum-contaminated groundwater from three spill-affected Minnesota sites—two contaminated with crude oil; one with diesel—is investigated to elucidate whether differences in degradation products from different parent oils exist. After spill events, parent molecules from the leaked oil seep underground and undergo microbial degradation over time, transforming into hydrocarbon oxidation products (HOPs), water-soluble contaminants that infiltrate groundwater aquifers, flowing into nearby environments and towns while exhibiting environmental persistence, toxicity to aquatic biota, and potential risks to humans that become exposed. Spectroscopic and chromatographic study of the structural themes and spatial distributions of HOPs reveals preferential degradation of aliphatic (biolabile) …

How Does Hummock Creation In Submerging Salt Marshes Alter Nitrous Oxide Fluxes?, Juliette Doyle

Honors Scholar Theses

Climate change is altering ecosystems and the services they provide. Salt marsh ecosystems typically protect coastal areas and filter nitrogen out of water, but are rapidly submerging due to rising sea levels and human development that prevents landward migration. Recent restoration efforts to preserve salt marshes attempt to build elevation capital and promote vegetation and animal habitat, but it is unclear how such efforts affect salt marsh biogeochemistry and dynamics of nitrous oxide, a potent greenhouse gas. To better understand how adding sediment to submerging salt marshes may alter nitrous oxide fluxes, I leveraged a salt marsh hummock creation experiment …

Environmental Factors Associated With Triploid Aspen Occurrence In Intermountain West Landscapes, James A. Walton

All Graduate Theses and Dissertations, Fall 2023 to Present

Polyploidy is common among plants and can contribute to physiological and morphological differences, altering how plants respond to environmental changes, promoting genetic diversification and even species radiation. Quaking aspen (Populus tremuloides), a keystone species associated with high plant and animal diversity is frequently found in mixed diploid/triploid populations in the Intermountain West. Triploid aspen carries an extra chromosomal copy, whereas the diploid type contains two chromosomal copies. High mortality rates and widespread population declines in aspen are of increasing concern in the Intermountain West, and often ascribed to changing climates and drought stress events. The goal of this …

Assessing Nordihydroguaiaretic Acid Properties And Its Potential Therapeutic Effect For Glioblastoma, Jose Arturo Guerrero

Open Access Theses & Dissertations

This study employs a combination of theoretical and experimental analysis to spectroscopically investigate the biomechanistic structure relationship and therapeutic effects of the Nordihydroguaiaretic Acid (NDGA) chemical derived from the Larrea Tridentata plant. These relationships are crucial for understanding NDGA's efficacy in disease prevention, treatment, and potential toxicological effects. While the medicinal and antiviral properties of the NDGA have been studied extensively, there remains a gap in optically identifying and reporting its structural changes. The current research successfully reveals evident trends in NDGA's vibrational signatures, particularly highlighting the absence of the Raman feature at 780 〖cm〗^(-1) as indicative of a fully …

Assessing Urban Tree Coverage Along The U.S.-Mexico Border: A Gis Analysis Of Paso Del Norte, Melanie Escobar

Open Access Theses & Dissertations

In recent years, researchers have extensively studied the spatial distribution of social demographics and urban tree canopy (UTC) in urban cities, but very few, to this date, address U.S.-Mexico border cities. To date, there is no research that assesses the distribution of urban tree canopy (UTC) in the city of El Paso, Texas, and Ciudad Juarez, Chihuahua, along the U.S.- Mexico border. Leveraging advanced mapping techniques and GIS tools, the study performs comparisons between countries (Juárez vs. El Paso urbanized areas and intra-country (within each country). It compares land cover classifications, assesses variations in UTC distribution across census tracts and …

Water Sufficiency For Organismal Function In Dryland Critical Zones, Lindsey Dacey

Open Access Theses & Dissertations

Water availability is crucial for organismal survival and growth in dryland environments, affecting both ecological interactions and carbon dynamics. The goal of this thesis is to develop soil water release curves (SWRCs) that link soil water potentials (Ψ) to soil water content (θ). Using the SWRCs, temporal soil water sufficiency curves are developed, which quantify the amount of time that dryland critical zones have enough water to sustain the physiology of organisms. These curves allow for effectively indicating water availability across different species, coverage types, and soil conditions, enhancing our understanding of water dynamics in drylands and contributing important parameters …

Evaluation Of The Extent Of Floods In 2022 In Different Land Cover And Land Use Classes In Sindh Province, Pakistan Using Sentinel-1 And Sentinel-2 Imageries, Alina Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Floods are one of the most frequent and most devastating natural disasters, which cause widespread destruction and pose significant risks to human life, infrastructure, and the environment. Advancement in remote sensing technologies and methodologies have demonstrated their efficacy in disaster-related applications, such as the detection, monitoring, and analysis of floods. This study explores the utilization of Synthetic Aperture Radar (SAR) and optical imagery for flood extent mapping and studying the extent of flood over various land cover and land use classes in Pakistan's Sindh province, utilizing the cloud computing power of Google Earth Engine. The change detection method identified extensive …

Grading Climate Action Plans In The Midwest, Megan Baker

Department of Environmental Studies: Undergraduate Student Theses

As agreed upon by international climate scientists, decarbonization in the American Midwest is critical to keeping the planet below the 1.5C increase in global temperature from pre-industrial levels. However, most previous research that evaluates climate action plans (CAPs) to find their weaknesses and provide policy recommendations neglects this crucial region of the United States. To fill this gap, this paper replicates Deetjen et al.’s (2018) review of CAPs in 29 US cities by applying their CAP rubric to 11 Midwestern cities. The results of both quantitative analysis were used to analyze the differences in plans in the Midwest versus the …

The Influence Of Methyl Orange On The Co2-Brine Wettability Of Organic-Acid-Aged Calcite Samples: Implications For Co2 Geo-Storage, Fatemah Alhammad, Mujahid Ali, Nurudeen Yekeen, Muhammad Ali, Mohammadreza Kamali, Stefan Iglauer, Alireza Keshavarz

Research outputs 2022 to 2026

The underground storage of CO2 in a depleted carbonate formation is a suitable method for limiting its anthropogenic release and minimize global warming. The rock wettability is an essential factor controlling the mechanisms of CO2 trapping and its containment safety in the geo-storage formation. The geo-storage rock contains innate organic acids which alters the wettability of the rock surface from the hydrophilic condition to the hydrophobic state, thus reduce the CO2 storage capacity. In this study, methyl orange which is a toxic dye that is generally released into environment was used as wettability modifier to change the wettability of stearic …

Skimming Genomes For Systematics And Dna Barcodes Of Corals, Andrea M. Quattrini, Luke J. Mccartin, Erin E. Easton, Jeremy Horowitz, Herman H. Wirshing, Hailey Bowers, Kenneth Mitchell, María Del P. González-García, Makiri Sei, Catherine S. Mcfadden

School of Earth, Environmental, & Marine Sciences Faculty Publications

Numerous genomic methods developed over the past two decades have enabled the discovery and extraction of orthologous loci to help resolve phylogenetic relationships across various taxa and scales. Genome skimming (or low-coverage genome sequencing) is a promising method to not only extract high-copy loci but also 100s to 1000s of phylogenetically informative nuclear loci (e.g., ultraconserved elements [UCEs] and exons) from contemporary and museum samples. The subphylum Anthozoa, including important ecosystem engineers (e.g., stony corals, black corals, anemones, and octocorals) in the marine environment, is in critical need of phylogenetic resolution and thus might benefit from a genome-skimming approach. We …

Conversion Of Microcrystalline Cellulose To Hexane Using Hydrogenated Metal Oxides At Low Temperature And Pressure, Mubarak Osman

Electronic Theses and Dissertations

Increasing global energy demand and environmental concerns have fueled the exploration of sustainable and efficient methods for renewable fuel production. The conversion of cellulosic waste to hydrocarbon fuels using hydrogenated metal oxides presents a novel and eco-friendly approach to sustainably address energy demand. In this study, hydrogenated metal oxides were used as catalysts in a relatively low-temperature and atmospheric-pressure environment to facilitate the conversion of cellulosic waste into hydrocarbon fuels. Hydrogenated metal oxides have been introduced as potential hydrogen transfer catalysts. The expected result is the selective conversion of cellulose to hexane at relatively low temperatures, which significantly reduces energy …

Use Of Modelling Tools To Assess Climate Change Impacts On Smallholder Oil Seed Yields In South Africa, Priscilla Ntuchu Kephe, Siyabusa Mkuhlani, Farirai Rusere, Abel Chemura

All Peer-Reviewed Publications

Oil seed crops are the second most important field crops after cereals in the agricultural economy globally. The use and demand for oilseed crops such as groundnut, soybean and sunflower have grown significantly, but climate change is expected to alter the agroecological conditions required for oilseed crop production. This study aims to present an approach that utilizes decision-making tools to assess the potential climate change impacts on groundnut, soybean and sunflower yields and the greenhouse gas emissions from the management of the crops. The Decision Support Tool for Agrotechnology Transfer (DSSAT v4.7), a dynamic crop model and the Cool Farm …

Chemical Composition, Fate, And Toxicity Of Dissolved Hydrocarbon Oxidation Products In High Latitude Aquatic Environments, Maxwell Louis Harsha

LSU New Orleans Theses and Dissertations

Oil spilled in aquatic environments undergoes abiotic and biotic oxidation processes that produce hydrocarbon oxidation products (HOPs). HOPs rapidly diffuse in the water column, persisting and readily bioavailable to aquatic organisms. Characterizing HOPs is challenging because most of the mixture resides in the unresolved complex mixture (UCM). Understanding of the formation, fate, and toxicity of HOPs in high latitude environments remains limited. This research addresses these gaps through a comprehensive experimental approach, utilizing various analytical techniques including nonvolatile dissolved organic carbon (NVDOC) analysis, ultrahigh-resolution mass spectrometry, tandem mass spectrometry, inductively coupled plasma mass spectrometry, and fluorescence excitation-emission matrix spectroscopy. Additionally, …

Catchment-Scale Thawing And Greening Decreases Long-Term Nitrogen Export In Ne Greenland, Shannon L. Speir, Jennifer L. Tank, Ada Pastor, Marc F. Muller, Mikhail Mastepanov, Tenna Riis

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Climate change is expected to alter nitrogen (N) export from Arctic rivers, with potential implications for fragile coastal ecosystems and fisheries. Yet, the directionality of change is poorly understood, as increased mobilization of N in a 'thawing' Arctic is countered by higher rates of vegetative uptake in a 'greening' Arctic, particularly in the understudied region of Greenland. We use an unprecedented dataset of long-term (n = 18 years) river chemistry, streamflow, and catchment-scale changes in snow and vegetation to document changing riverine N loss in Greenland. We documented decreasing inorganic and organic N loads, linked to decreasing snow stores, …

High Intraspecific Diversity Of Pocillopora Damicornis In Southeast Asia Reflects Adaptive Potential To Climate Change, Maria Lucille Carr

Theses and Dissertations

Marine heatwaves are increasing in intensity and frequency because of increased emissions of greenhouse gases. On coral reefs, warmer temperatures cause coral bleaching, mortality, and shifts in benthic composition. However, coral bleaching responses and survival vary geographically. Several hypotheses may explain such geographical differences in thermal tolerance, including the possibility that some localities may support higher intraspecific diversity than other localities, increasing the likelihood of survival of some individuals through heatwaves. Here we assessed geographic patterns of intraspecific genetic diversity in the ubiquitous coral Pocillopora damicornis. Intraspecific genetic diversity was assessed for 428 sequences across 44 sites in the Pacific …

Channel Response To Flow Augmentation: Diamond Fork River, Ut, Diane E. Wagner

All Graduate Theses and Dissertations, Fall 2023 to Present

A river’s physical features and channel dimensions are determined by the water and sediment supplied to it. The Diamond Fork River, located in central Utah—received large trans-basin diversion flows from 1915-2003, providing an exceptional opportunity to explore the response of a river to a large increase in flow.

Our project goals were to describe 1) channel response to this large and long artificial flow augmentation and 2) how the channel recovered after the removal of the diversion flows. The objective of this thesis is to document the channel condition throughout the 20^th century to present day as a basis …