Physical Sciences and Mathematics Commons^™

A Conceptual Model Evaluation Framework For Adaptive Governance And Adaptive Management In Large-Scale Restoration Programs, Chadwin Smith

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

Adaptive management (AM) has become a kind of plastic phrase applied as a formulaic panacea for most major species recovery and ecosystem restoration efforts now underway across the United States. AM emerged as an application of the scientific method to resource management, closely tying management to science learning through experimental actions. The phrase “learning by doing” best captures the premise behind developing an experimental management approach that could be applied on the larger scale of a river system or ecosystem. In nearly five decades of application, however, examples of successful AM implementation at large scales are few and conflict remains …

Food System Resilience In Nigeria: Farmers Perspective, Azariah Lawal

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

Disturbances are inherent in every socio-ecological system (SES). However, the spate and scope of upheavals in contemporary SES has increased dramatically in recent years. Agricultural systems are perhaps the most impacted when disasters occur because different aspects of agricultural production are directly affected. The burgeoning farmers-Fulani herdsmen conflict in West Africa is a manifestation of these challenges. When faced with events like these, contemporary food systems are faced with two options: collapse or transform. It is essential to have resilient agricultural systems because these systems lie at the nexus of resolving emerging global issues.

Nigeria is an important country in …

Impacts Of Irrigated Agriculture On The Near Surface And Planetary Boundary Layer Atmosphere: Results From The Great Plains Irrigation Experiment (Grainex), Emilee Lachenmeier

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

Modification of natural prairie grasslands into irrigated and rainfed agriculture in the Great Plains produced significant impacts on regional weather and climate including temperatures, precipitation, energy fluxes, and the planetary boundary layer (PBL) atmosphere. The Great Plains Irrigation Experiment (GRAINEX) during the 2018 growing season collected data over irrigated and non-irrigated crop fields to further understand these impacts. The data were collected during two intensive observation periods (IOPs) in early June (IOP 1: 30 May – 13 June of 2018) and late July (IOP 2: 16 July – 30 July of 2018). The data analyzed include latent (LE) and sensible …

Population Demographics, Distribution, And Environmental History Of Asian Carp In A Great Plains River, Jake Werner

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

Silver Carp Hypophthalmichthys molitrix, Bighead Carp H. nobilis, and Black Carp Mylopharyngodon piceus, collectively known as Asian carp, are a group of invasive fishes in the U.S.A. that have garnered much attention over the last couple decades. Most research devoted to this group of fishes has been focused in the Mississippi River basin with little investigation in the Missouri River drainage, particularly in tributary systems. The Kansas River is a major tributary to the Missouri River that has multiple anthropogenic barriers creating varying levels of connectivity within the Kansas River itself, and with the Missouri River. Information …

Use Of Citizen Science In Monitoring Groundwater Quality: A Case Study From Nebraska, Christopher Olson

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

Citizen science has a key role in modernizing effective communication between professional scientists and the general public. However, citizen science differs to that of professional science due to equipment and experience and is a topic argued against citizen science. However, technology in water quality testing has developed in simplicity and affordability to a point where high school students, with hands-on training, can collect groundwater samples and test for quality themselves. Nebraska groundwater quality is a critical part of the state and can utilize high school students as citizen scientists for their communities. High school students from rural communities across Nebraska …

Nitrate Dynamics And Source Within Nested Watersheds Of An Agricultural Stream, Nebraska, Usa, Galen Richards

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

Nitrate concentrations have been increasing throughout the globe, primarily due to heightened agricultural activity. Nitrate concentrations in Bazile Creek, located in Northeastern Nebraska, have been steadily rising since the early 2000s. Groundwater nitrate concentrations within the Bazile Creek watershed are high (> 10 mg/L nitrate-N), and there is strong connectivity between groundwater and surface water systems. This study aimed to better understand temporal nitrate concentration variability within the watershed through sampling tributaries and the main channel during baseflow conditions. Nitrate source was also investigated though the use of dual δ¹⁵N and δ¹⁸O nitrate isotopes, with samples …

Spatial Ecology And Resource Selection Of Bighorn Sheep (Ovis Canadensis) Ewes In A Prairie Badlands Population, Erin Wood

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

The basic spatial ecology and habitat relationships of female bighorn sheep in Nebraska are poorly understood. Establishing seasonal patterns of space use and resource selection for this population at the margin of their historical and current range addresses a key knowledge gap and provides important baseline information for ongoing conservation efforts in Nebraska. We deployed GPS radio-collars on 56 adult ewes in western Nebraska to quantify seasonal space use, movements, and resource selection of ewes. To investigate spatial ecology, we quantified movements of ewes and the factors that influence home range size, seasonal use, and spatial stability across seasons. Home …

Using Return Intervals And Nutrient Spiraling To Examine The 2019 Nebraska Flood, Alexa Davis

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

In March of 2019, flooding levels in many parts of Nebraska was the worst that streams and rivers had in decades, and in some locations, on record. Theses historic floods present an optimal case study to examine how current technological resources can be used to enhance our understanding of floods and how these floods impact in situ stream ecosystem processes like nitrogen and phosphorus cycling. Currently, there are only a few resources available to quantify the extent of floods; for my thesis, I will focus on satellite imagery and in situ water level gages. Unfortunately, due to technical issues with …

Using The Elaboration Likelihood Model As A Method To Teach Science Communication, Ann Briggs

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

For most scientists, researchers, and resource professionals, the act of communicating their science is not the focus of their training or practice. While the importance of sharing information with the general public is widely accepted, many professionals have not been taught how to communicate with the public. They rely on trial and error and other methods that often lead to misunderstanding and miscommunication. Science communication is a necessary step to keep society engaged and informed about science and the scientific process, and a lack of science communication to the public leads to misinformation, and ultimately a lack of trust in …

Recreational Activity Dynamics At Valentine National Wildlife Refuge, Olivia A. Darugna

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

Many parks and protected areas are managed for a dual purpose to conserve ecological systems and to provide wildlife-compatible recreational opportunities for visitors. Managing parks and protected areas to meet this dual goal entails progressive management approaches that incorporate information about social and ecological components of these systems. Current management regimes focus heavily on the ecological component with little or no information concerning the social component of parks and protected areas. Incorporating social information is essential for understanding and accounting for social conflicts and ecological impacts that result from a diversity of recreational activities. We examined recreational activities at Valentine …

Charismatic Predators In Modern Africa: Spotted Hyena (Crocuta Crocuta) And Human Coexistence In The Northern Tuli Game Reserve, Botswana, Jazmin Castillo

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

Increasing human populations has led researchers to investigate the impacts of high human population density and its impact on carnivore populations. Spotted hyenas (Crocuta crocuta) hold a unique place in African ecosystems due to being a very successful top predator with an adaptable diet whereas other top predators, like the African lion, are rapidly decreasing in abundance. We investigated past and current spotted hyena abundance within the Northern Tuli Game Reserve to better aid in wildlife management. Spotted hyenas showed no significant difference in the change in population abundance throughout the different years of the study (2008-2016). Spotted …

The Effects Of Temperature On Evacuation Rates And Absorption Efficiency Of Flathead Catfish, Zach Horstman

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

Knowledge of fish gastric evacuation rates are a necessary component for both field and laboratory studies when trying to understand feeding rates, modeling energy budgets, and understanding trophic dynamics of aquatic ecosystems. Many freshwater fish encounter a broad range of environmental temperatures across life history stages, but the mechanistic link between temperature and physiological processes often remains poorly understood. We designed three recirculating aquatic systems capable of rearing Flathead Catfish Plyodictis olivaris in order to quantify gastric evacuation rates and gross energy absorption at three temperatures (17º C, 22º C and 25º C). We examined the relationship between temperature and …

In Hot Water: Influence Of Multiple Stressors On Thermal Tolerance Of Fathead Minnows Pimephales Promelas, Alexander Engel

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

Freshwater aquatic systems around the globe are often subjected to physical, biological, and chemical alterations to support societal needs. The Great Plains contains one of the largest agricultural industries in North America, but its productivity has ecological repercussions for adjacent freshwater ecosystems. Specifically, the dependency on surface water irrigation and application of chemical treatments has altered the thermal and chemical composition of freshwater ecosystems throughout the region. Stressors such as elevated temperatures, altered flow regimes, increased contaminant loads affect the physiology and behavior of fishes and can lead to long-term population effects. We examined thermal tolerance of Fathead minnows Pimephales …

Comprehensive And Agricultural Greenhouse Gas Emissions Inventories For Nebraska And The Midwest As Baselines For Climate Change Mitigation, Eric R. Holley

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

Climate change is the paramount challenge of today for a sustainable future. Mitigation of greenhouse gas (GHG) emissions is necessary to reduce the associated risks and impacts on society. Using the EPA’s SIT and literature review, comprehensive GHG-emissions inventories were developed for the state of Nebraska over 25 years (1990-2015) and agricultural GHG emissions inventories were developed for the Midwest U.S for one year (2016). Nebraska’s net emissions increased from 56.2 million metric tons of carbon dioxide equivalent (MMtCO₂e) in 1990 to 87.4 MMtCO₂e in 2016. Agriculture was found to be the sector with the most …

Impact Of Streambank Stabilization On Sediment Deposition And Erosion In Central Nebraska Streams, Matthew Russell

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

Stabilization projects are increasingly used to mitigate the effects of anthropogenic streambank erosion, yet the effectiveness of these practices has been insufficiently monitored and assessed to date. Sound monitoring practices promote engineered effectiveness, in addition to allowing adjustments in implementation and maintenance to improve practices over time. However, current methods to quickly and efficiently quantify deposition and erosion within a stream continue to be costly and inefficient. Therefore, the objectives of this project were to 1) Measure streambank migration of three reaches at Cedar River in Nebraska, from 1993 to 2006 (pre-stabilization) and from 2006 to 2018 (post-stabilization) using aerial …

Exploring How Graduates Of The Nebraska Water Leaders Academy Influence Community Capitals: Two Case Studies, Dakota Staggs

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

Natural resources are foundational to any community and so leadership regarding those resources is a key factor to consider in order to understand communities. The vitality and strength of a community, however, is not solely dependent upon the natural resources available to it but depends on the collection of assets and individuals within it. This study sought to understand how individual leaders, graduates of the Nebraska Water Leaders Academy, influence each of the seven community capitals outlined by Flora, Flora, and Gasteyer (2016), and how their individual civic capacity, as defined by Sun and Anderson (2012), contribute to community capacity. …

Prairie Grouse Population Trends And Their Historical Drivers In The Nebraska Sandhills, Danielle Berger

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

The Nebraska Game and Parks Commission (NGPC) has monitored greater prairie-chickens (Tympanuchus cupido pinnatus) and plains sharp-tailed grouse populations (Tympanuchus phasianellus jamesi), collectively known as prairie grouse, since the 1950s using spring breeding ground counts. My research modeled long-term, species-specific spatial and temporal trends of prairie grouse abundance and potential environmental drivers in the Sandhills of Nebraska using NGPC’s historical monitoring data. Prairie-chicken populations have increased since the 1950s while sharp-tailed grouse populations have remained stable or slightly declined. These population trends arise in the context of a dynamic landscape. I created indices representing raptor predation …