Hydrology Commons^™

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, …

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 …

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 …

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 …

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 …

Groundwater Education: An Investigation Of Students' Use Of A Groundwater Modeling Tool, Holly White

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

Groundwater is a critical resource for life on Earth. However, our groundwater resources are at risk due to human activities, making this a topic of importance within K-12 and undergraduate environmental education. Yet, students hold alternative conceptions and may have limited awareness about groundwater systems. One way to support students’ learning is by incorporating computer-based modeling tools into classrooms. Here, we explore the use a groundwater modeling tool, the Hydrogeology Challenge (HGC), among two age groups of students: seventh grade students and undergraduate students. In the seventh-grade population, we investigated how students relate or map model components to their real-world …

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 …

Occurrence And Potential Transformation Pathways Of Nitrogen Species In The Intermediate Vadose Zone, Jordan Shields

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

Nebraska is a large agricultural producing state with a heavy reliance on groundwater resources and nitrogen fertilizer application to maintain output. Poor management, such as excessive fertilizer application, improper timing, and over irrigation can lead to contamination of groundwater. Nitrate is the leading groundwater contaminant in Nebraska and chronic consumption at medium to high concentrations leads to adverse health effects. Nitrate, a highly soluble anion, is present in the root zone in numerous forms and undergoes biogeochemical transformations before being leached through the profile. In order to predict the timing and quantity of nitrate contamination in groundwater, researchers study the …

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 …

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 …

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 …

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 …

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 …

Geoscience Education Research: Trends And Applications In Undergraduate Courses, Diane Lally

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

Water resources are progressively under pressure from anthropogenic uses. Students need to learn about water systems as they are the future decision-makers and problem solvers who will be faced with unknown challenges in the future. The overarching goals of this dissertation were: 1) to identify ways in which geoscience instructors are incorporating systems thinking and science modeling in their teaching along with the accompanying methods for improving systems thinking and modeling implementation and 2) explore how the implementation of science modeling and systems thinking increase student evaluation of models and the understanding of hydrologic content. Data for these studies came …

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 …

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. …

Improving Aquifer Characterization Through Integration Of Airborne Electromagnetics (Aem) And Well Hydrographs, Jacqueline Polashek

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

The objective of this study is to evaluate methods of hydrostratigraphic modeling using geophysics and well hydrographs at the eastern edge of the High Plains aquifer (HPA) in Platte and Colfax counties within Nebraska, USA. The HPA is very heterogeneous in the study area, being hosted by architecturally complex glacial sediments and having many irregular hydraulic boundaries. Further, the HPA exhibits local variations between unconfined and confined conditions. Pumping in such bounded aquifers can be unsustainable because of cost increases and lost agricultural productivity. Moreover, the large drawdowns typical of confined aquifers can contribute to well interference during heavy pumping. …

Drought Impacts Assessment In Brazil: A Remote Sensing Approach, Denis Mariano

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

Climate extremes are becoming more frequent in Brazil; studies project an increase in drought occurrences in many regions of the country. In the south, drought events lead to crop yield losses affecting the value chain and, therefore, the local economy. In the northeast, extended periods of drought lead to potential land degradation, affecting the livelihood and hindering local development. In the southern Amazon, an area that experienced intense land use change (LUC) in the last, the impacts are even more complex, ranging from crop yield loss and forest resilience loss, affecting ecosystem health and putting a threat on the native …

Regime Detection Measures For The Practical Ecologist, Jessica L. Burnett

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

Forecasting undesirable change is, arguably, the holy grail of ecology. Paired with an understanding of system interactions, a forecast is ideal if it provides reliable predictions in sufficient time to prevent or mitigate unwanted systemic change. Early warning systems (or early warning signals, early warning indicators) have been developed and tested for some ecological systems data, but have been mostly applied to marine fisheries time series and nutrient loadings in shallow lakes. Despite the numerous quantitative methods proposed for identifying or forecasting regime shifts in ecological data, few are used in practice. This dissertation contributes to our understanding of the …

Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest, Mary G. Keilhauer

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

The Midwestern United States is vulnerable to eutrophic conditions from high nutrient concentrations. Recommendations for nonpoint source pollution management include runoff treatment (i.e., filter strips, riparian buffers) and in-situ lake treatment practices (i.e., aluminum sulfate (alum) treatments, aeration, up/downdraft pumping, floating treatment wetlands). Floating treatment wetlands (FTWs) are an innovative wetland design for nutrient removal from nonpoint sources and provide a unique in-situ treatment. Best management practice studies have commonly focused on adjacent to water practices, which have resulted in a gap for guidance for in-situ treatment placement and design. Therefore, the objectives of this project were to (1) Quantify …

Evaluation Of The Metric Model For Mapping Energy Balance Components And Actual Evapotranspiration For A Super-Intensive Drip-Irrigated Olive Orchard, Samuel Ortega

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

A field experiment was carried out to evaluate the METRIC (Mapping EvapoTranspiration at high Resolution Internalized with Calibration) model for mapping net radiation (Rni), soil heat flux (Gi), sensible heat flux (Hi), latent heat flux (LEi), actual evapotranspiration (ETa) and crop coefficient (Kc) of a superintensive drip-irrigated olive (Olea europeae L. cv Arbequina) orchard located in Pencahue Valley, Region del Maule, Chile (35 23’ LS; 71 44’ LW; 96 m above sea level). The study was conducted in an experimental plot of 21.1 hectares using 9 satellite images (Landsat 7 ETM+) acquired on clear sky days during 2011/2012 and 2012/2013 …

Developing A Framework To Link Multi-Sector Drought Impacts To Drought Severity At The State Level, Mary Noel

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

The United States Drought Monitor, a weekly map depicting severity and spatial extent of drought, is a key indicator for federal and state policy decisions including the annual distribution of hundreds of millions of dollars for agricultural financial relief in the United States. However, the current table describing potential drought impacts for the map’s severity levels fails to adequately represent a state’s unique environmental, economic, and social values affected by drought. One approach to improve this broad, national-scale assessment is to transition from the former platform to a more detailed characterization of drought impacts at the state level. To accomplish …

Investigation Of Grace-Derived Information On Forest Drought Stress Across The Contiguous Us, Beichen Zhang

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

This research derives z-score monthly groundwater storage (GWS) anomalies and z-score monthly root zone soil moisture (RZSM) anomalies from products of Gravity Recovery and Climate Experiment Data Assimilation (GRACE-DA). Z-score monthly GWS and RZSM anomalies are compared to two drought indicators: Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration Index (SPEI) to investigate the usefulness of GRACE-DA information to detect drought conditions at tree-ring sites. This study also compares z-score monthly GWS and RZSM anomalies with the Tree Ring Standardized Growth Index (TRSGI) that is resampled by bootstrapping to investigate the capability of monitoring forest drought stress. Finally, this research uses …

The Niobrara National Scenic River: Exploring Co-Management Through A Case Study Of The Niobrara Council, Melissa M. Mosier

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

In recent decades, government staff and local citizens have increasingly employed cooperative schemes of natural resource management, in lieu of more conventional, top-down approaches of addressing user conflicts as they relate to water resources. The focus of this project was on the Niobrara Council, a partnership of local, state, and federal representatives charged with cooperatively managing the reach of the Niobrara River that was federally designated under the Wild and Scenic Rivers Act in 1991. The project's purpose was to explore the cooperative framework of the Council, using the methodology outlined by Carlsson and Berkes (2005). This methodology involved investigating …

Population Dynamics Of The Freshwater Mussel Lampsilis Cardium Reintroduced In Nebraska, Lindsay M. Ohlman

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

The global decline of native freshwater mussels has accelerated conservation projects that preserve and restore populations, but the complex life histories among species challenges biologists in determining the most effective management strategies. This study details the conservation of plain pocketbook, a Tier I threatened mussel species in Nebraska that was artificially propagated and reintroduced into 13 sites from autumn 2016 to summer 2017. The objectives of this study were: 1) determine how handling influences mussels, and 2) evaluate mussel growth and survival following introductions.

We conducted a laboratory experiment with age-2 plain pocketbook to assess the effects of handling on …

Hunter And Angler Motivations, Preferences, And Barriers To Waterfowl Hunting In The Central United States, Matthew P. Hinrichs

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

Since the mid-1980s, there has been a decrease in individuals participating in waterfowl hunting in the United States. The decline in participation has over-arching consequences for state and federal wildlife agencies in their ability to fund and manage habitat and waterfowl populations. There is a fundamental need to understand why individuals participate in waterfowl hunting and what barriers there are to participating in waterfowl hunting. An online survey was conducted in the summer and fall of 2018 asking waterfowl hunters, anglers, big game hunters, combination users (i.e., hunters that have multiple hunting and fishing permits), and small game hunters about …