Digital Commons Network^™

Forecasting Natural Regeneration Of Sagebrush After Wildfires Using Population Models And Spatial Matching, Andrii Zaiats, Megan E. Cattau, David S. Pilliod, Rongsong Liu, Juan Miguel Requena-Mullor, Trevor Caughlin

Human-Environment Systems Research Center Faculty Publications and Presentations

Context Addressing ecosystem degradation in the Anthropocene will require ecological restoration across large spatial extents. Identifying areas where natural regeneration will occur without direct resource investment will improve scalability of restoration actions.

Objectives An ecoregion in need of large scale restoration is the Great Basin of the Western US, where increasingly large and frequent wildfires threaten ecosystem integrity and its foundational shrub species. We develop a framework to forecast where postwildfire regeneration of sagebrush cover (Artemisia spp.) is likely to occur within the burnt areas across the region (>900,000 km²).

Methods First, we parameterized population models …

Practical Improvements For Pivot And Surface Irrigation, Jonathan A. Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Irrigation is critical to meeting global food and fiber demands. Optimizing agricultural irrigation may help sustain production levels, while reducing its demand for water. This research evaluated precision sprinklers and drip irrigation for pivots, five pivot track mitigation tools, three scientific irrigation scheduling (SIS) methods, sensors for surface irrigation cutoff, and automating surface systems to implement surge irrigation. With pivots and surface irrigation being the most common methods for irrigation in the West, small improvements from these tools could result in significant water savings.

Low energy precision application (LEPA) sprinklers and mobile drip irrigation (MDI) were tested on two pivots. …

Cross-Boundary Stewardship In Protected Area Centered Ecosystems: Perceptions Of Success And Characteristics Of Cooperative Engagement, Ryan D. Tarver

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The legal boundaries of protected areas, such as national parks are established and enforced by humans. Therefore, jurisdictional boundaries are ultimately have human meaning but not necessarily ecological relevance as natural phenomena such as watersheds and wildlife habitat often extend beyond a jurisdictional boundary. When considering the extent of natural system, we find that protected areas only make up part of a given ecosystem. The result is a large expanse of lands that fall under a various ownership types that include both publicly and privately designated tracts of land. This presents a management challenge when attempting to manage at the …

Partitioning And Microdosimetry Of Plutonium-239 And 55-Iron In Environmental Bacteria Grown In Liquid Cultures, Lisa Manglass

All Dissertations

The work presented herein provides quantitative data related to bacteria exposed in situ to two radionuclides relevant to nuclear sensing: plutonium-239 (²³⁹Pu) and iron-55 (⁵⁵Fe). Originally motivated by the fundamental science underlying biosensing, liquid cultures of Pseudomonas putida and Escherichia coli were exposed to radionuclides over the course of 15-day experimental periods with the intent of gaining insight into the response of these bacteria. An essential component of characterizing or utilizing this response in a meaningful way is an understanding of the dose leading to that response. This dissertation narrows the knowledge gap associated with dose-response …

Investigating The Difference Between Members In The High-Resolution Rapid Refresh Ensemble (Hrrre) During The February 23rd, 2022 Winter Storm, Michael Barletta

Atmospheric & Environmental Sciences

Probabilistic forecasting is one tool that is being used to help create more accurate and understandable forecasts. Using percentages and probabilities allows for more depth to a forecast and allows forecasters to be able to convey a clearer message of what exactly they are expecting. Ensembles are a set of forecast models that have either different starting conditions, boundary conditions or parameter settings. They are one way of creating probabilistic forecasts and can help in the understanding of the likelihood of a specific outcome. Forecasters use ensembles to attempt to analyze the range of possible outcomes and the likelihood of …

State Of Utah Et Al. V Walsh Et Al., Ethan Halman Gonzalez

Department of Environmental Studies: Undergraduate Student Theses

To expand upon that, the State of Utah et al. wants to show the Department of Labor’s “Prudence and Loyalty in Selecting Plan Investments and Exercising Shareholder Rights” Rule proposed in December 2022, is arbitrary and capricious under the Administrative Procedure Act (APA) and Employment Retirement Income Security Act of 1974 (ERISA). The suit argues that the Department of Labor (DOL) oversteps the APA—as under the APA, the Court “shall… hold unlawful and set aside agency action, findings, and conclusions” that are “in excess of statutory jurisdiction, authority, or limitations,” or “arbitrary capricious, an abuse of discretion, or otherwise not …

The Decline Of Upland Birds In Nebraska: Maximizing Limited Habitat, Hunter Tesarek

Department of Environmental Studies: Undergraduate Student Theses

Ring-necked Pheasants were introduced into the United States around 150 years ago and since then have become an important species both culturally and economically. There population health is of growing concern as upland bird populations in much of the United States have been declining rapidly throughout the latter half of the last century. In Nebraska millions of acres have been transformed from habitat that benefits upland birds into row crop agriculture, mostly in the form of corn and soybeans. Rural Mail Carrier Surveys conducted for pheasants from 1960 through 2020 in comparison to change in acres harvested depict the relationship …

Consumer Valuation And Preferences For Sustainably Produced Rice In Ghana, Vera Adabrah-Danquah

Graduate Theses and Dissertations

Sustainable agricultural production is a systematic concept that integrates environmental health, economic profitability, and social/economic equity goals. Improving the sustainability of food production is of utmost importance to the human race, given the growing population and the increased depletion of natural resources. Improving sustainability is particularly important for rice, a global food staple with a significant environmental footprint. Rice accounts for 10% of global methane emissions. The Sustainable Rice Platform (SRP) standard is the first globally recognized certified sustainable production standard for rice. This study focuses on consumers' preferences for sustainable rice in Ghana, including consumers’ perceptions of different SRP's …

Greenhouse Gas Emission Reduction Plan, Lauren Bruhl, Guinter Vogg, Gabe Hamburg, Shanu Sankara, Rohan Kansagra, Colin Page, Colette Vynerib

Sustainability Exchange Projects

Our team aimed to compile a greenhouse gas inventory for the St. Louis region. Partnered with OneSTL, Ameren, and the USGBC, we determined that St. Louis has a goal to reduce emissions 50% by 2030 from 2005 levels, and become carbon neutral in 2050. After analyzing the Ameren’s Integrated Resource Plan and factors such as the cost and scope of emissions, we researched funding sources to improve energy efficiency and increase renewables in the region. Our top funding sources are the Inflation Reduction Act (IRA) and the Bipartisan Infrastructure Law (BIL). From the IRA, we found the following credits most …

Can Renewable Portfolio Standards Explain The U.S. States’ Advancement Of Wind Energy?, Elise Monson

Political Science Theses and Capstones

No abstract provided.

Hydrologic Implications Of Snow-Vegetation Interactions In A Semiarid Mountain Climate, Maggi Kraft

Boise State University Theses and Dissertations

Knowledge of the complex interaction between snow, vegetation, and streamflow in semiarid mountain climates is necessary for predicting water resources. The effects of warming temperatures on snow distribution will cascade into vegetation water use and streamflow. Due to our reliance on snow water resources, it is necessary to understand how vegetation affects snow distribution, how vegetation uses snow water inputs and the subsequent effects on streamflow in the current and warming climate. The overall objective of this research is to improve our understanding of snow-vegetation interactions in a semiarid climate. In this dissertation, I use field data to evaluate how …

Understanding The Operations And Decision-Making Of Cow-Calf Farmers In Northwest Arkansas, Clayton Weyl

Agricultural Economics and Agribusiness Undergraduate Honors Theses

Societal pressure on farmers has become a more central part of the rhetoric surrounding livestock production. This study includes farmers in the discourse on the rhetoric surrounding climate change via interviews and simulations tailored to their operation. Previous research has addressed regenerative agricultural practices and conditions that influence farmer decision-making, but little research has analyzed decision-making in tandem with environmental practices. The literature reveals that cow-calf producer decision-making is influenced by their reliance on cattle as an income source, and farmers overall choose climate-friendly practices based on their perceptions about climate change. The goal of this research was to gather …

A Consumer's Guide To Greenwashing, Katie Fowler

Marketing Undergraduate Honors Theses

Over the past 37 years since the term greenwashing was coined, there have been sparse attempts to regulate this deceptive environmental marketing. The Federal Trade Commission (FTC) created its Guides for the Use of Environmental Marketing Claims, also known as the Green Guides, in 1992. The Guides have been revised on three separate occasions – 1996, 1998, and 2012 – in an attempt to remain relevant with the proliferation of environmental marketing claims and trends. However, the Guides were created as interpretive rules that do not give the FTC the authority to enforce the regulations unless they can prove that …

Remote Sensing To Advance Understanding Of Snow-Vegetation Relationships And Quantify Snow Depth And Snow Water Equivalent, Ahmad Hojatimalekshah

Boise State University Theses and Dissertations

Snowpack is an important source of freshwater in mountainous regions. Understanding the role of different controls on snow properties (depth, distribution, and snow water equivalent (SWE)) and processes (accumulation and ablation) is important to predict available freshwater. Snow processes vary with respect to the predominant local controls in different landscapes. In many mountainous landscapes, controls on snow properties and processes are highly correlated with vegetation properties. In this dissertation, to elucidate the relationships between snow and vegetation, I use terrestrial laser scanning to explore how forest canopy structure affects snow depth distribution. In addition, I examine different vegetation metrics to …

Evaluating Snow And Ice Cover In Tierra Del Fuego, Argentina, Zoe Pitman

Geosciences Undergraduate Honors Theses

Evaluating changes in snow and ice cover is an important field for studying climate change and its impacts. This evaluation is commonly done using remote sensing because of its ability to evaluate large areas. The purpose of this study is to determine the reliability of one remote sensing technology, the Moderate Resolution Imaging Spectroradiometer (MODIS), by comparing it to in-situ snow and climate data from the weather station at the Austral Center for Scientific Research (CADIC). Data was converted from daily to monthly averages and was sorted into a series of graphs to compare the two data sets. Correlations were …

Effect Of Elevated Temperature And Roundup Exposure On Oxidative Stress And Antioxidant Status In The American Oyster, Afsana Chowdhury

Theses and Dissertations

Aquatic organisms are frequently exposed to various environmental stressors. In this study, we observed the short-term (1-week) combined dose-dependent effect of Roundup, a glyphosate-based herbicide, and high temperature (30°C) on the morphology of gills and digestive glands, expression of heat shock protein-70 (HSP70), dinitrophenyl protein (DNP), nitrotyrosine protein (NTP), antioxidant enzymes such as catalase (CAT) and superoxidase dismutase (SOD) in tissues of American oyster (Crassostrea virginica). Histological analyses showed an increase in mucous production in the gills and digestive glands, hemocyte aggregation in the connective tissues as well as structural change of the lumen in the digestive glands …

Flow Monitoring And Tidal Exchange Ratio Estimation For The Bahia Grande After Widening Of The Carl Joe Gayman Pilot Channel: Bahia Grande, Cameron County, Tx, Sabas Lopez Iii

Theses and Dissertations

The Bahia Grande (BG) is an 8,500-acre set of coastal bays and wetlands located between Brownsville and Port Isabel, Tx, near the Gulf of Mexico (GOM) coastline. In 2005, the Carl Joe Gayman Pilot Channel was constructed to address hypersalinity concerns that resulted from natural and anthropogenically-caused tidal isolation since the early 1940’s. In 2022, the Texas General Land Office (GLO) increased the channel’s width and depth in anticipation of increasing tidal exchange ratios by a factor of two to three. Once the channel widening was complete, two SL-1500-3G side-looking acoustic doppler current profilers (ADCPs) were periodically deployed beneath the …

Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder

Theses and Dissertations

Air pollution is a substantial environmental challenge all over the world. This study investigated the long-term air pollution levels in the Lower Rio Grande Valley region, by utilizing data collected from five continuous ambient monitoring stations in two counties over 23 years, from January 2000 to December 2022, to analyze daily, monthly, and seasonal variations of different pollutants, including ground-level ozone, particulate matter, and carbon monoxide. This study also identified distinct daily and seasonal patterns for O3, PM2.5, PM10, and CO at each monitoring site, influenced by factors such as traffic emissions, temperature, solar radiation, indoor heating, and weather conditions. …

Predictive Ecology And Management Of Phyllosphere Microbial Communities Through Cross-Scale Synthesis, David W. Armitage, Morgan E. Carter, Robin A. Choudhury, Mitja Remus-Emsermann, Cindy E. Morris, Johan H. Leveau, Linda L. Kinkel, José Pablo Dundore-Arias

School of Earth, Environmental, & Marine Sciences Faculty Publications

Here we summarize the main takeaways from a symposium and hybrid virtual and in-person participatory discussion focused on the challenges of scale in understanding the ecology and management of phyllosphere microbial communities. We provide an overview of the confounding effects of spatial scale on inference in microbial ecology, the spatial organization of microbial interactions in the phyllosphere, advances and remaining gaps in measuring phyllosphere colonization across scales, and the epidemiology in the phyllosphere. We hope to motivate further discussion and the development and adoption of creative approaches to solving the challenges of scale to enhance fundamental understanding and practical management …

Catalytic Water Photolysis For Generating Renewable Hydrogen Fuel, Dr. Niveditha Nanda

Open Access Theses & Dissertations

Modern advances have enabled rapid industrialization and urbanization. However, the consequences of global modernization have included significant pollution to the air and water resources. Consequently, many changes to energy use must come to address and mitigate damages to our future. Solar energy derived hydrogen gas is a clean, renewable fuel that does not produce carbon dioxide or other pollutants. My research investigates the use of heterogeneous photocatalysis, by focusing on solar photochemical energy conversion, which is the making of hydrogen from water using sunlight. The production of clean, renewable hydrogen fuel will enable the utilization of low-cost, pollution-free energy resources …

Characterizing Spatial Variability In Soil Co2 Fluxes In The Chihuahuan Desert Using Geostatistical Techniques, Viridiana Orona

Open Access Theses & Dissertations

Spatial variability in soil CO2 efflux across landscapes is an important feature of the â??Critical Zoneâ?? within dryland ecosystems. In dryland critical zones, resources are often distributed in patches or resource islands. Although this is particularly true in natural settings, the significance of spatial variability in CO2 efflux and its patterns also extends to dryland agriculture. In both irrigated and unirrigated systems, human management practices can significantly impact both organic and inorganic carbon cycling processes, highlighting the importance of studying CO2 efflux in these systems. We examined the spatial patterns of soil CO2 efflux and quantified the magnitude and scale …

Potential Control Of Invasive Mesquite Through Improving The Consumer’S Understanding Of Liquid Smoke Applications., Seth W. Ellsworth

Graduate Theses and Dissertations

Mesquite trees continue to invade forests and range lands in many countries across the world. The cost to remove these trees is staggering. In Texas, landowners spent $25 million over a 10- year period to clear 300,000 ha of mesquite trees, a fraction of the 22 million ha of Texas land affected by this invasion. Estimates are that the mesquite continues to negatively impact one to two percent of additional land in selected counties each year in Texas. However, the problem is not unique to Texas, but rather to the 44 species of mesquite trees, belonging to the genus Prosopis …

The Transaction Costs Of Federal Environmental Policy Changes: The Effects Of The Temporary Covid-19 Cwa Rollback On Local Water Systems, Jesse Lee Barnes

UNLV Theses, Dissertations, Professional Papers, and Capstones

An institutional dilemma exists between the Clean Water Act (CWA) and the Safe Drinking Water Act (SDWA). US surface waters are protected from point-source pollution by the CWA. Community Water Systems (CWSs) that draw from these surface waters for potable purposes are required to treat that water to a level that meets SDWA health standards. Therefore, decreases in CWA regulations could lead to surface water quality declines and, thus, higher SDWA compliance costs for CWSs. This area of inquiry has become increasingly relevant due to Trump-era executive actions to try to decrease the federal government's role in multiple environmental policies, …

Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Desert springs are aquatic oases, being considered among the most diverse and imperiled ecosystems on Earth. Despite the ecological significance and threatened status of desert springs, few studies have surveyed the microorganisms in these systems or their interactions with other community members. The primary goal of this dissertation was to describe the major controls influencing the community ecology of prokaryotic and BMI communities in cold- and moderate-temperature desert springs of the southern hydrographic Great Basin. Chapter 1 provides a broad overview of spring ecosystems and of each chapter included in this dissertation. Chapter 2 documents the first-ever, regional-scale survey of …

Morphologic Comparisons Of Recrystallized And Neocrystallized Fibrous Amphibole Asbestos: Implications For Corresponding Health Risk Potential, Natalie G. Renkes

UNLV Theses, Dissertations, Professional Papers, and Capstones

The presence of naturally-occurring asbestos (NOA) is increasingly concerning for scientists, health and regulatory agencies, and citizens living in impacted areas. It is commonly believed that fibrous amphibole asbestos can only form through neocrystallization. In southern Nevada, NOA occurs as a result of hydrothermal alteration of granitic rock producing fibrous amphibole both as cross-cutting neocrystallized veins and via recrystallization of original magmatic hornblende crystals. Fibers with a greater aspect ratio are known to have increased toxicity. This study measured the maximum length and average width of both neocrystallized and recrystallized fibers to see if the morphologies were similar. Neocrystallized and …

The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Assessing the role geographic isolation and ecological specialization have on phylogeographic patterns contributes to our understanding of the evolutionary history of a species and the processes that erode genetic diversity. I used mitochondrial and nuclear genomic sequences to assess whether habitat isolation has shaped the fine-scale patterns of present-day genetic structure and diversity in two threatened insect species endemic to southern Nevada. Pseudocotalpa giulianii (Coleoptera; Scarabaeidae) is a dune obligate scarab beetle endemic to only two small, isolated sand dunes in Nye County, Nevada, with a usable habitat of less than 4.2 km sq that is impacted by on-going degradation. …

Storm Surge Risk Assessment In Coastal Communities In The Rio Grande Valley: An Application Of Gis-Based Spatial Multicriteria Decision Analysis With Analytical Hierarchy Process, Dean Kyne

Sociology Faculty Publications

Cameron County, which is located in the Rio Grande Valley, maintains records of storm surges associated with noticeable property damage, fatalities, and injuries. This study investigates storm surge inundation risk in Cameron County using storm surge hazard datasets from the National Oceanic and Atmospheric Administration, along with American Community Survey 2019 block group datasets. Using a GIS-based spatial multicriteria decision analysis with an analytical hierarchy process method, the study estimates that storm surge water levels could be above 6.1 m (20 ft) in category 4 and 5 hurricane events, whereas about 37% of the county’s population (159,659 people) could be …

Monte-Carlo Modeling Of Bidirectional Reflectance In Shallow Turbid Water, Tyler Anthony Rotkiske

Theses and Dissertations

The ability to model surface and bottom boundary layers using water column information in shallow waters is mathematically approached using a Monte-Carlo model. The hyperspectral Monte-Carlo model used in this research was previously developed and analytically validated. This mathematical model tracks photons in 3-dimensional space and includes the effects of small gravity waves on the water surface, the bottom reflectance, and constituents within the water column. This type of modeling uses a probabilistic approach and is the only method used to calculate shape factors and mean cosines in a water column and then verified using hyperspectral remote sensing reflectance measurements. …

Correlation Between Fire And Preservation In The Pacific Northwest And Most Cost-Efficient Mitigation Tactics, Liam Doherty-Herwitz

Department of Environmental Studies: Undergraduate Student Theses

This study was conducted entirely online with occasional help from advisors and editors on zoom meetings. I completed the research in Lincoln, Nebraska. A meta analysis of online data has been conducted to form the answers to my hypotheses and research questions. I used specific keywords and phrases in research databases, and search engines such as google scholar to point me towards the answers I was looking for. The keywords and phrases were split up into four different categories which are mitigation techniques, ecosystems, fire severity: PNW, and fire season: PNW. The reason the topics land preservation and fire science …

Identifying A Consumer–Producer Agricultural Knowledge Gap, Aspen Rittgarn

Department of Environmental Studies: Undergraduate Student Theses

The purpose of this paper and online survey was to see if an agricultural knowledge gap between consumers and producers be found. Low agricultural literacy rates can lead to misconceptions of the agriculture industry, unhealthy food choices, environmentally unfriendly product choices, food waste, etc. The hypothesis for this thesis is that those born in the mid1960s to early 1980s (Generation X) will be the start of an increased knowledge gap. The survey was compiled of both qualitative and quantitative questions and questions were inspired by American Farm Bureau’s AITC Benchmarks. Responses were analyzed and the results revealed that my participants …