Other Environmental Sciences Commons^™

Population Demography Of A Glacial-Relict Stream Fish Mediated Via Anthropogenic Alteration, Joseph M. Spooner

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

Northern Pearl Dace Margariscus nachtriebi are a small-bodied glacial-relict fish species of greatest conservation need (SGCN) found throughout Canada and the northern United Sates. Their distribution within the Nebraska Sandhills Ecoregion is isolated from the northern core distribution of the species following the last glaciation period approximately 18,000 years ago. Headwater streams within the Nebraska Sandhills Ecoregion are predominately groundwater fed and provide the cool water temperatures needed to support Northern Pearl Dace and other glacial-relict SGCN. Headwater streams within the Nebraska Sandhills Ecoregion have been geomorphically altered through anthropogenic processes such as channelization whereby habitat homogenization has occurred. Evidence …

Habitat Heterogeneity In Nebraska Streams And Distribution Prediction For Tier-1 Cyprinids Using Multi-Scale Modeling Of Fluvial And Landscape Features, Connor P. Hart

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

Multiscale environmental processes determine in-stream habitat conditions which drive species distributions. Habitat constitutes the physical template upon which ecological processes occur and species conduct life stage activities. Habitat heterogeneity promotes biodiversity of aquatic systems. Stream classification informs freshwater conservation by providing a useful framework to account for habitat heterogeneity, often based on landscape regions of similar environmental processes. A greater understanding of landscape-based classification frameworks as means to classify stream systems may improve understanding of drivers of biodiversity. Using Nebraska as a case study, on a statewide scale, objectives were 1) to characterize habitat availability for several at-risk fish species, …

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 …

Precipitation And Greenness In Pastoral Lands Of East Turkana, Kenya, Paul Akpejeluh

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

Pastoralism has long supported livelihoods and provided essential ecosystem services in landscapes of East Africa. Vegetation productivity is central to the functioning of pastoral systems but may be affected by changes in climate and landuse. Vegetation monitoring is important for understanding the effects of global change in pastoral lands; however, it can be time and resource intensive. Remote sensing provides opportunities for efficient multi-scale monitoring of vegetation and climatic drivers. In this thesis, I explore the utility of satellite and UAV remote sensing for monitoring vegetation and precipitation trends and relationships in the East of Lake Turkana Region of northern …

Understanding The Factors Affecting Nebraskan Farmers’ And Landowners' Decision To Adopt Precision Agricultural Technologies And Programs, Corrin C. Winter

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

Advisors: Andrew Little, Christopher Chizinski

To gain insights into the challenges faced by Nebraska farmers and landowners when adopting precision agriculture technologies, I analyzed data collected from a 2022 survey involving 7,503 participants, consisting of producers and farmland owners from across the state of Nebraska. The primary objective was to provide valuable insights for agencies seeking to improve their precision agriculture and conservation outreach efforts for the benefit of conservation and Nebraskan farmers and landowners. This study aimed to understand key factors influencing adoption behaviors by evaluating the constraints to precision agriculture adoption, assessing the impact of producer and landowner …

Pronghorn Survival And Resource Selection In Western Nebraska's Agriculturally Dominated Landscape, Katie Piecora

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

Nebraska’s pronghorn population has been stable over the last decade, yet their presence on the landscape remains a contentious subject amongst private landowners. Conversion of grassland for crop production and increased anthropogenic activity has drastically altered pronghorn behavior throughout their current range, however basic ecology and resource use by pronghorn in Nebraska remains poorly understood. Establishing baseline population metrics and seasonal patterns of resource use for this population at the eastern periphery of the species range is critical to guide management actions. We deployed GPS collars on 110 adult pronghorn to quantify survival, mortality risk, and seasonal resource selection in …

Critical Factors And Individual Decision Making In Earthquake And Tsunami Preparedness Among Coastal Communities Inoregon U.S.A., Shelley Olds

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

Earthquakes and tsunamis are natural hazards that cause considerable loss of life, destruction of property and infrastructure, and economic damage. Preparedness is critical in regions of significant earthquake and tsunami risk. A key challenge for organizations that manage hazard preparedness and response is mobilizing earthquake preparedness among individuals and families. This dissertation provides an examination of individual earthquake and tsunami preparedness from both a global and regional perspective. It comprises two publications that explore various aspects of disaster preparedness.

Chapter One provides an overview of global seismic and tsunami hazards, along with potential impacts, and addresses the challenges in promoting …

Mentoring Experiences Of Undergraduate Students And Faculty Members In Science, Technology, Engineering, And Mathematics, Pamela Martínez Oquendo

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

I present a comprehensive view of mentoring experiences of undergraduate students and faculty members in science, technology, engineering, and mathematics (STEM). In CHAPTER 1, I describe a brief outline of this dissertation. In CHAPTER 2, I present an interpretative phenomenological analysis of the lived experiences of former STEM undergraduate mentors of the Nebraska STEM For You (NE STEM 4U) afterschool mentoring program. In CHAPTER 3, I describe how the ramifications of faculty mentorship influence the science pipeline using a qualitative synthesis. In CHAPTER 4, I describe how the STEM faculty-student mentoring engagement involves a strong psychological support component using a …

Bat Use Of Afforested And Encroached Patches And Their Role In Extending Bat Habitat Into The Nebraska Sandhills, Jacob L. Wagner

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

The Nebraska Sandhills are currently undergoing a state shift to a redcedar dominated woodland due to anthropologic planting of eastern redcedar (Juniperus virginiana) and woody encroachment from the periphery of the Sandhills. To better understand this novel ecosystem and how bats are utilizing it I collected data at Barta Brothers Ranch with acoustic sensor grids consisting of 24 100m spaced acoustic sensors placed adjacent to planted windbreaks. Supplemental data from the Nebraska North American Bat Monitoring Program was used for data analysis at larger spatial scales. I used linear regressions and kriging interpolation maps to see how bats used windbreaks …

The Role Of Gender And Curiosity On Transformational Leadership: A Mixed-Methods Study, Brooke Colleen Mott

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

Environmental leaders are tasked with finding innovative solutions to dynamic environmental challenges. Leaders must gain and use new knowledge and experiences that motivate resolving gaps in one’s knowledge (i.e., curiosity) and thereby find forward-thinking solutions. Although curiosity is an integral part of human existence, it may be experienced in various ways. Studies have shown that men and women may possess different leadership styles. Nevertheless, the influence of curiosity on leadership between genders has not been as readily explored. Women exhibit unique characteristics for successful leadership in many contexts, but they are often underrepresented in natural resource management overall. Characteristics of …

Sturgeon Chub Distributional Patterns And Habitat Use And Benthic Fish Assemblage Structure In Missouri River Tributaries Of South Dakota, Mitchell R. Magruder

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

Native species of the Missouri River drainage inhabiting benthic habitats dominate state and federal lists of species at risk. Sicklefin Chub Macrhybopsis meeki and Sturgeon Chub Macrhybopsis gelida are two native Missouri River benthic minnows that are currently under review for federal listing under the Endangered Species Act (ESA) due to extensive population declines and local extirpations within their native range. Substantial alterations to the Missouri River threaten Macrhybopsis spp. and other benthic fishes; however, large, less impacted tributaries in South Dakota may act as refugia for native species. The extent of Sicklefin Chub and Sturgeon Chub populations is largely …

The North Platte River Valley: The Intersectionality Between Water Quality And People, Anni Poetzl

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

The North Platte River (NPR) Valley of western Nebraska is a semi-arid watershed with row crop production, livestock production, and urban land use activity and has a population of diverse stakeholders. These land use activities contribute to the enrichment of surface waters, such as streams, which can affect human and ecosystem health, as well as economic development and recreational activities. The project objectives are to: (1) quantify the movement of dissolved inorganic nutrients from the land within the NPR Valley to the NPR via tributaries and canals, (2) identify spatiotemporal variability of nutrient limitation of periphyton growth within the NPR, …

Landscape Change, Scale, And Human Response To Change In The Great Plains, Kate Bird

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

Great Plains landscapes are undergoing changes at multiple spatial and temporal scales due to processes ranging from woody encroachment to climate change. These changes may fundamentally alter the agroecosystems of the Great Plains such that the provisioning of ecosystem services including biodiversity and livestock production is affected. Improving our understanding of the effects of landscape change at multiple scales and how humans perceive and respond to these changes is important for facilitating research and management that enhances the resilience of these agroecosystems. As such, I first applied discontinuity theory and graph theory to evaluate the functional connectivity of the Central …

Understanding Conservation Specialists’ Role In The Adoption Of Precision Agriculture In Nebraska, Morgan L. Register

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

There is a complex issue by the need for strategic development of agricultural lands to ensure we can feed a growing world, while simultaneously reducing impacts on our natural resources such as water pollution from runoff, soil degradation, and habitat fragmentation. To address these growing concerns, researchers are looking for ways to optimize both agricultural production and natural resource conservation. Precision conservation was developed to ensure sustainable ecosystems for future generations. Our research evaluates conservation specialists’ ability to clearly articulate how precision conservation can help agricultural producers feed a growing world while simultaneously reducing impacts on our natural resources, I …

Analysis Of Soil Change Across Nebraska, Trinity Baker

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

The world’s population is growing and an increasing populace requires more resources. These requirements place increasing pressure on the environment and the soil. Soils serve many important functions throughout the world. These functions range from offering a media for food production, providing a sink for organic carbon, nutrient cycling, and improving water quality. It is important to focus on the human impact on soils and their change over time.

For my research I examined how soils across Nebraska have changed over a time period of roughly 65 years. I sampled and analyzed 39 pedons from four Major Land Resource Areas …

Towards Usable Environmental Information: A Case Study With The Santee Sioux Nation, Alexis Chavez

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

Across the United States (U.S.), Indigenous peoples have developed and implemented adaptation plans to improve their resilience to climate and weather disturbances. An essential component of these plans is to use environmental information effectively. Institutions like universities and government agencies usually provide this information, and its usability depends on the information’s quality and the relationships that establish its accessibility and validity. However, many studies have shown that much of this information is not usable for its intended users. Additionally, there has been little research into the issues that can affect Indigenous peoples’ usage of environmental information in the U.S. Therefore, …

Secondary Science Teachers Use Of Models In Teaching And Learning About Earth’S Climate, Kimberly Carroll Steward

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

Global climate change (GCC) presents unprecedented global concerns, notably food supply limitations, unsustainable use of natural resources, and widespread environmental degradation. The International Panel on Climate Change (IPCC) reports a 0.85 °C increase in global average temperatures between 1880 and 2018 and a 50% increase in global carbon dioxide emissions since 1990 (Stocker et al., 2018). As a result of the urgency of the situation, there is a strong emphasis on empowering citizens through outreach and education. There is a need to adequately prepare the next generation of scientists, politicians, business leaders, and other people; it is crucial to foster …

Coupling Dendrochronology And Remote Sensing Techniques To Assess The Biophysical Traits Of Juniperus Virginiana And Pinus Ponderosa Within Grassland Communities In The Semi-Arid Grasslands Of The Nebraska Sandhills, Reece Allen

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

Woody species encroachment is occurring within the sandhills region in Nebraska, primarily driven by Juniperus virginiana and Pinus ponderosa, altering ecosystems and the services they provide. Effective, low cost, and cross-scale monitoring of woody species growth and performance is necessary for integrated grassland and forest management in the face of climate variability and change. In this study, we sought to establish a relationship between remote sensing-derived vegetation indices (VIs) and dendrochronological (raw and standardized tree ring width) measurements to assess the performance of encroaching woody J. virginiana and P. ponderosa located within the Nebraska National Forest in the sandhills. …

Multi-Criteria Evaluation Model For Classifying Marginal Cropland In Nebraska Using Historical Crop Yield And Biophysical Characteristics, Andrew Laws

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

Marginal cropland is suboptimal due to historically low and variable productivity and limiting biophysical characteristics. To support future agricultural management and policy decisions in Nebraska, U.S.A, it is important to understand where cropland is marginal for its two most economically important crops: corn (Zea mays) and soybean (Glycine max). As corn and soybean are frequently planted in a crop rotation, it is important to consider if there is a relationship with cropland marginality. Based on the current literature, there exists a need for a flexible yet robust methodology for identifying marginal land at different scales, which …

An Investigation Of The Attitudes And Behavioral Outcomes Of Nebraskan Hunters Toward Tick-Borne Disease, Dominic J. Cristiano

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

As changes in climate, land-use, and vegetation alter the landscape of the Great Plains, new threats to public health are emerging. Incidences of tick-borne disease in Nebraska have increased nearly 250% over the past two decades – newly established species like Ixodes scapularis may introduce challenges for health practitioners, including more cases of Lyme disease. Strategies for tick-borne disease prevention must incorporate effective health messaging. Audience segmentation may be a useful technique to provide health communication, as it allows for targeted messaging that speaks to specific attitudes and beliefs of a given population. One tool for usefully segmenting populations is …

Outdoor Play In Preschool Children: Parent Attitudes And Loose Part Play In Urban Settings, Ann Spilker

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

Outdoor play is an important aspect of young children’s health social-cognitive development. However, play in natural environments is declining due to urbanization and various safety concerns. Many urban preschools have outdoor play spaces that lack natural elements that stimulate children’s autonomy, creativity, and imaginative play. Furthermore, parents who find outdoor environments intimidating and fraught with danger limit young children’s outdoor experiences that inhibit their motor fitness, socialization with peers, and ecological awareness. Two qualitative case studies examined preschool children’s outdoor play. Study one focused on preschool children’s loose parts play in urban settings while study two examined parent’s attitudes towards …

A Mixed Methods Case Study: Effects Of Instructors’ Beliefs On Incorporation Of Sustainability Curriculum At A Midwestern University, Anna Oetting

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

The degree to which sustainability is taught is often varied and inconsistent across colleges, departments, and higher education institutions. However, educating students and future generations regarding the different pillars of sustainability, including economic, social, and environmental topics, is increasing in importance and urgency. A mixed methods case study utilized surveys and interviews to investigate why instructors incorporate sustainability, what impacts course incorporation of sustainability, and barriers that instructors face. This study found that instructors’ beliefs regarding the importance of sustainability relate to the extent to which sustainability is incorporated into their curriculum. Topics of sustainability incorporated into a class are …

Irrigation’S Impact On A Precipitation Event During Grainex In Nebraska, Usa, Daniel Whitesel

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

Numerous precipitation events were observed during the Great Plains Irrigation Experiment (GRAINEX). However, the precipitation event that was observed the morning of 23 July 2018 is the focus of this thesis. Six experiments were conducted which involved increasing or decreasing soil moisture by 5% increments over the irrigated cropland. An additional experiment, which changed the irrigated land use to grassland, showed precipitation increases. It was found that regardless of strength of irrigation, average precipitation decreased. Average precipitation decreased by up to 72% when irrigation increased compared to the control simulation and decreased by up to 85% when irrigation decreased compared …

Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler

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

In Nebraska and other regions of the Great Plains, the conifer Juniperus virginiana (eastern redcedar) is converting grasslands to dense woodlands. This is driven by the interacting drivers of fire suppression, altered grazing regimes, climate change and other anthropogenic factors, impacting the provisioning of ecosystem services. This vegetation state transition modifies water resource regulation and biogeochemical cycles leading to altered edaphic properties including soil microbial community composition. To restore these grasslands and control J. virginiana spread, prescribed extreme burns are implemented as a management tool through local prescribed burn associations. We hypothesized that the alternative state transition to dense J. …

Spatiotemporal Trends In Bacterial Diversity Across Three Watersheds Within The Platte River Basin, Nebraska, Esther Perisho

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

River bacteria are understudied despite being critical components of river ecosystems. There are even fewer studies considering bacteria communities at large spatiotemporal scales, which may provide insight into drivers of community assembly. We investigated differences in bacterial diversity across environmental gradients within three sub-basins nested in the Platte River Basin, Nebraska. Surface water samples were collected weekly at 36 sites from May to September by the Nebraska Department of Environment and Energy (NDEE) in 2019. Bacterial communities were sequenced using the Illumina MiSeq platform. Sub-basins had similar counts of unique amplicon sequence variants (ASVs) but different community structures. These structural …

Right Side Up: Payment For Ecosystem Services On Privately Owned Grasslands In Nebraska, Kyle Martens

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

Grasslands are an important ecological and economic resource in the United States. As part of a natural system, these landscapes can provide income for ranching operations and employment in rural communities; habitat for grassland plants, animals, and migratory species; and offer other services not always readily observed such as improved soil health, clean water, and carbon sequestration. Despite the overarching benefits, the conversion of grasslands to other uses remains widespread throughout much of the remaining Great Plains ecosystem.

Shifting from livestock ranching to another land use often reflects a tipping point. This occurs when the alternative land use is perceived …

Understanding And Contextualizing Foraging Among Recreational Opportunities In The North Central United States, Iris I. Mcfarlin

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

Over the past few decades, there has been a resurgence in popularity and recognition of foraging for wild products and foods. Despite the cultural importance and ubiquity of foraging, there have been relatively few scientific investigations (as compared to other consumptive outdoor activities such as hunting and fishing) of the social factors influencing foraging behavior, landscape preferences, and the types of materials foraged in the United States. As such, there is a fundamental need to understand more about the practice and about those who participate. We conducted two surveys to gather information on foragers’ motivations and demographic characteristics and to …

Soil Morphology And Carbon Stocks Of Deflation Basin Wetlands In Eastern Nebraska, Usa, Aubrey Grace Kemper

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

Wetlands contribute important ecosystem services such as water filtration and storage, wildlife habitat, and carbon sequestration. The objective of this study is to compare the soil morphology and the carbon and nitrogen stocks between the upland, basin edge, and basin floor in playa wetlands of eastern Nebraska. This work was conducted in three deflation basin wetlands in the Todd Valley, a loess-mantled, former course of the Platte River, in eastern Nebraska. Soil morphological descriptions were evaluated to two meters’ depth using cores collected along three transects from the upland to the basin floor in three basins, carbon and nitrogen stocks …

Bioaccumulation And Partitioning Of Heavy Metals In Cicindelidia Haemorrhagica In Yellowstone National Park, Monica Gotschall

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

The tiger beetle Cicindelidia haemorrhagica (Coleoptera: Cicindelidae) are widely distributed in Yellowstone National Park (YNP) and exclusively living on thermal areas. Heavy metals including arsenic, copper, lead, and selenium are present in these thermal springs, presenting an unique environment for C. haemorrhagica. Therefore, from 2018 – 2020 I sampled adult C. haemorrhagica from YNP and adult C. haemorrhagica from a known population in a salt flat in Idaho not associated with a hot spring and measured heavy metal concentrations. All populations of C. haemorrhagica bioaccumulated heavy metals. Cuticular waxes showed small concentrations of metals indicating that those metals are …