Digital Commons Network^™

Leaf Optical And Indirect Lai Measurements In Wheat And Alfalfa At Maciv: Agmet Progress Report 89-4, E. A. Walter-Shea, B. L. Blad

School of Natural Resources: Documents and Reviews

No abstract provided.

Occurrence, Inputs, And Ecological Significance Of Antibiotics And Pharmaceuticals In Western Nebraska Streams, Katelyn F. Glause

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

Few emerging environmental contaminants are as concerning as antibiotics. Human and animal health benefits greatly from the prudent use of antibiotics, yet we give little thought to environmental release of these biologically active compounds. Environmental occurrence of these and other pharmaceutical compounds must be measured in different environmental compartments such as municipal wastewater and in the vicinity of large animal feeding operations to understand potential effects. This study reports the results of a monitoring study in western Nebraska, with a large population of livestock and smaller but more concentrated population of humans, comparing the relative environmental concentrations and loading from …

Applying Circuit Theory To Describe Changes In Structural Landscape Connectivity In Response To Wildfire, Christian Ross Nielsen

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

Understanding and conserving ecological connectivity is critical to the preservation of vulnerable landscapes. Circuit theory, in which landscapes are imagined as circuit boards with varying resistances to the flow of current, is being increasingly used to model spatially explicit connectivity of landscapes and to inform land management and conservation decision-making. Utilizing continuous, quantitative estimates of percent cover by five land cover functional groups to create a conductance surface, this study expanded upon an established application of circuit theory that used the open-source software Circuitscape to model species-agnostic, omnidirectional connectivity. This model was automated using Python to create time-series connectivity maps …

Assessing, Restoring, And Centering Social-Ecological Relationships For Advancing Social-Ecological Resilience In The Northern Great Plains Grasslands, Katia Pilar Carranza Bernal

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

The Northern Great Plains grasslands are social-ecological systems that were shaped by evolutionary and Indigenous social-ecological relationships. European colonization disrupted many of these interactions, including the coupling of fire and grazing, and degraded social-ecological resilience, shifting these grasslands to a new state. For those reasons, my research focused on assessing, restoring, and centering evolutionary and Indigenous social-ecological relationships for advancing social-ecological resilience in the Northern Great Plains grasslands. I first performed a study in the Nebraska Sandhillls assessing the potential of patch-burn grazing to support grassland resilience by comparing its effects to those of rotational grazing. Through vegetation and bird …

Analysis Of Drought-Flood Abrupt Alternation Events And Their Impacts In Kenya, Betty Makena

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

Drought-Flood Abrupt Alternation (DFAA) is a compound disaster event that refers to the abrupt shift of extreme drought events to extreme floods resulting in exacerbated impacts on already vulnerable communities and hindering their coping abilities. This study aimed to analyze drought-flood abrupt alternation events and their impacts in Kenya. The first chapter aimed to understand historical drought events in the Greater Horn of Africa and their impacts, while drawing comparisons with the recent 2020-2022 drought period, referred to as the ‘triple dip La Niña’. Datasets used in this study include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), Normalized …

Impacts Of Invasive Carp And Their Population Dynamics On Fish Communities In The Missouri River, Joshua F. Kocik

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

Invasive Carp species: Silver Carp Hypophthalmichthys molitrix, Bighead Carp Hypophthalmichthys nobilis, Grass Carp Ctenopharyngodon idella, and Black Carp Mylopharyngodon piceus have both potential and realized abilities to negatively impact native species. Specifically, Bighead Carp and Silver Carp as filter feeders have been theorized to be detrimental not only to adult filter-feeding species, but to many fish which rely on plankton and algae in their early-life stages. The impact of Invasive Carp on the overall fish community remains underexplored. The fish communities below Gavins Point Dam (Invasive Carp present) and Fort Randall Dam (Invasive Carp absent) afford the …

Remotely Sensed Early Warning Of Algal Blooms In An Eastern Nebraska Reservoir: A Comparison Of Temporal And Spatial Indicators, Mercy Kipenda

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

Cyanobacterial harmful algal blooms (CyanoHABs) detrimentally affect human, animal, and ecosystem health. Remotely sensed early warning systems for cyanoHABs in inland lakes could contribute to more proactive water quality monitoring and help mitigate negative impacts. Advances in freely available remote sensing imagery, with finer spatial, temporal, and spectral resolutions, present new opportunities for the development and comparative analysis of methods to detect sudden deterioration in lake water quality. In this thesis, I compared and tested for temporal and spatial early warning signals of cyanoHABs in field-based and remotely sensed datasets from 2019 to 2023 in Pawnee Lake in southeast Nebraska, …

Population Demography, Occupancy, And Connectivity Of Invasive Bigheaded Carp In The Platte River, Nebraska And Its Tributaries, Blake W. Logan

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

Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis, collectively referred to as bigheaded carp, are invasive species in the United States of America that have expanded their range throughout the Missouri River basin in the last three decades. It may be desirable to develop management plans directed at the monitoring, control, or removal of bigheaded carp within the Missouri River basin. However, a knowledge gap exists regarding bigheaded carp ecology in Missouri River tributaries, which may be important for the development of management plans. As such, this study characterized bigheaded carp population demographics, occupancy, and connectivity in …

Virtual Fencing In Livestock Management: Effects On Beef Cattle Stress And Enhancing Wildlife Conservation, Kaitlyn E. Dozler

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

I examined the effects of virtual fencing on beef cattle stress and how implementing the technology can aid wildlife habitat conservation at the University of Nebraska Gudmundsen Sandhills laboratory (GSL) near Whitman, NE. First, I examined how virtual fencing influences acute heart rate changes in beef cattle fitted with the virtual fencing collars. No significant difference in the average heart rate of a cow (P > 0.05) was observed between the 30 min control and virtual fenced periods for both trial dates. Second, I examined the influence of topography on wildlife species richness and presence at GSL using wildlife camera …

What Climate Change Means For Nebraska

United States Environmental Protection Agency: Publications

Nebraska’s climate is changing. In the past century, most of the state has warmed by at least one degree (F). The soil is becoming drier, and rainstorms are becoming more intense. In the coming decades, flooding is likely to increase, yet summers are likely to become increasingly hot and dry, which would reduce yields of some crops, require farmers to use more water, and amplify some risks to human health.

Our climate is changing because the earth is warming. People have increased the amount of carbon dioxide in the air by 40 percent since the late 1700s. Other heat-trapping greenhouse …

Seeing Is Believing: Religious Views, Perceptions Of Pollution, And Environmental Attitudes, Katelynn (Sage) Shadoan

Department of Sociology: Dissertations, Theses, and Student Research

This study explores the intersection of religious beliefs, perceptions of pollution, and environmental attitudes among Americans. Drawing upon Lynn White's seminal argument regarding Christian theology and its implications for environmental stewardship, this research investigates the role of biblical literalism in shaping environmental attitudes, particularly among conservative Christians. Using nationally representative survey data and logistic regression models, the study examines how the perceptions of pollution moderate the effects of views of the Bible on environmental concern. The findings reveal that while perceived pollution exposure is strongly associated with environmental attitudes, it does not moderate the association between biblical literalism and environmental …

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

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

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

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

Stress Phenotyping Analysis Leveraging Autofluorescence Image Sequences With Machine Learning, Sruti Das Choudhury, Carmela Rosaria Guadagno, Srinidhi Bashyam, Anastasios Mazis, Brent E. Ewers, Ashok Samal, Tala Awada

School of Natural Resources: Faculty Publications

Background: Autofluorescence-based imaging has the potential to nondestructively characterize the biochemical and physiological properties of plants regulated by genotypes using optical properties of the tissue. A comparative study of stress tolerant and stress susceptible genotypes of Brassica rapa with respect to newly introduced stress-based phenotypes using machine learning techniques will contribute to the significant advancement of autofluorescence-based plant phenotyping research.

Methods: Autofluorescence spectral images have been used to design a stress detection classifier with two classes, stressed and non-stressed, using machine learning algorithms. The benchmark dataset consisted of time-series image sequences from three Brassica rapa genotypes (CC …

Globe-Lfmc 2.0, An Enhanced And Updated Dataset For Live Fuel Moisture Content Research, Marta Yebra, Gianluca Scortechini, Karine Adeline, Nursema Aktepe, Turkia Almoustafa, Avi Bar-Massada, María Eugenia Beget, Matthias Boer, Ross Bradstock, Tegan Brown, Francesc Xavier Castro, Rui Chen, Emilio Chuvieco, Mark Danson, Cihan Ünal Değirmenci, Ruth Delgado-Dávila, Philip Dennison, Carlos Di Bella, Oriol Domenech, Jean-Baptiste Féret, Greg Forsyth, Eva Gabriel, Zisis Gagkas, Fatma Gharbi, Elena Granda, Anne Griebel, Binbin He, Matt Jolly, Ivan Kotzur, Tineke Kraaij, Agnes Kristina, Pınar Kütküt, Jean-Marc Limousin, M. Pilar Martín, Antonio T. Monteiro, Marco Morais, Bruno Moreira, Florent Mouillot, Samukelisiwe Msweli, Rachael H. Nolan, Grazia Pellizzaro, Yi Qi, Xingwen Quan, Victor Esco De Dios, Dar Roberts, Çağatay Tavşanoğlu, Andy F. S. Taylor, Jackson Taylor, İrem Tüfekcioğlu, Andrea Ventura, Nicolas Younes Cardenas

School of Natural Resources: Faculty Publications

Globe-LFMC 2.0, an updated version of Globe-LFMC, is a comprehensive dataset of over 280,000 Live Fuel Moisture Content (LFMC) measurements. These measurements were gathered through field campaigns conducted in 15 countries spanning 47 years. In contrast to its prior version, Globe-LFMC 2.0 incorporates over 120,000 additional data entries, introduces more than 800 new sampling sites, and comprises LFMC values obtained from samples collected until the calendar year 2023. Each entry within the dataset provides essential information, including date, geographical coordinates, plant species, functional type, and, where available, topographical details. Moreover, the dataset encompasses insights into the sampling and weighing procedures, …

Demographic Consequences Of Off-River Nesting For Piping Plover (Charadrius Melodus) And Interior Least Tern (Sternula Antillarum Athalassos) In The Lower Platte River System, Nebraska, Elsa M. Forsberg

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

Piping plovers (Charadrius melodus; hereafter, plovers) and interior least terns (Sternula antillarum athalassos; hereafter, terns) are two avian species that nest along the Lower Platte River system (LPRS) in Nebraska. In the LPRS, river sandbars provide natural nesting habitat, but off-river sites provide substantial nesting habitat especially when sandbar habitat is scarce. Although presumed to be important for the persistence of plovers and terns, off-river habitat is not self-sustaining and predicted to decline. Understanding the vital rates of plovers and terns in the LPRS will inform the role of off- river sites in the future conservation …

Field Testing Of Gamma-Spectroscopy Method For Soil Water Content Estimation In An Agricultural Field, Sophia Becker, Trenton E. Franz, Tanessa Morris, Bailey Mullins

School of Natural Resources: Faculty Publications

Gamma-ray spectroscopy (GRS) enables continuous estimation of soil water content (SWC) at the subfield scale with a noninvasive sensor. Hydrological applications, including hyper-resolution land surface models and precision agricultural decision making, could benefit greatly from such SWC information, but a gap exists between established theory and accurate estimation of SWC from GRS in the field. In response, we conducted a robust three-year field validation study at a wellinstrumented agricultural site in Nebraska, United States. The study involved 27 gravimetric water content sampling campaigns in maize and soybean and ⁴⁰K specific activity (Bq kg⁻¹) measurements from a stationary …

Where East Meets West: Phylogeography Of The High Arctic North American Brant Goose, Robert E. Wilson, W. Sean Boyd, Sarah A. Sonsthagen, David H. Ward, Preben Clausen, Kathryn M. Dickson, Barwolt S. Ebbinge, Gudmundur A. Gudmundsson, George K. Sage, Jolene R. Rearick, Dirk V. Derksen, Sandra L. Talbot

School of Natural Resources: Faculty Publications

Genetic variation in Arctic species is often influenced by vicariance during the Pleistocene, as ice sheets fragmented the landscape and displaced populations to low-and high-latitude refugia. The formation of secondary contact or suture zones during periods of ice sheet retraction has important consequences on genetic diversity by facilitating genetic connectivity between formerly isolated populations. Brant geese (Branta bernicla) are a maritime migratory waterfowl (Anseriformes) species that almost exclusively uses coastal habitats. Within North America, brant geese are characterized by two phenotypically distinct subspecies that utilize disjunct breeding and wintering areas in the northern Pacific and Atlantic. In the …

Development Of A Composite Drought Indicator For Operational Drought Monitoring In The Mena Region, Karim Bergaoui, Makram Belhaj Fraj, Stephen Fragaszy, Ali Ghanim, Omar Hamadin, Emad Al‑Karablieh, Jawad Al‑Bakri, Mona Fakih, Abbas Fayad, Fadi Comair, Mohamed Yessef, Hayat Ben Mansour, Haythem Belgrissi, Kristi Arsenault, Christa Peters‑Lidard, Sujay Kumar, Abheera Hazra, Wanshu Nie, Michael Hayes, Mark D. Svoboda, Rachael Mcdonnell

School of Natural Resources: Faculty Publications

This paper presents the composite drought indicator (CDI) that Jordanian, Lebanese, Moroccan, and Tunisian government agencies now produce monthly to support operational drought management decision making, and it describes their iterative co-development processes. The CDI is primarily intended to monitor agricultural and ecological drought on a seasonal time scale. It uses remote sensing and modelled data inputs, and it reflects anomalies in precipitation, vegetation, soil moisture, and evapotranspiration. Following quantitative and qualitative validation assessments, engagements with policymakers, and consideration of agencies’ technical and institutional capabilities and constraints, we made changes to CDI input data, modelling procedures, and integration to tailor …

Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Articles
Chapters in Books
Books
Field Guides
Geologic Maps
Other Maps
Cover Photographs
Other Photographs
Newspaper and Other Articles
Test-Hole Logs
Television Programs
Geonotes
Abstracts
Reviews
Manuscripts Accepted (A), Submitted (S), or in Preparation (P)
Geologic Maps in Press
Geologic Maps-Nebraska
Public Documents
Miscellaneous Publications
Editing

Updated March 2024

Heavy Metal Movement Through Insect Food Chains In Pristine Thermal Springs Of Yellowstone National Park, Braymond Adams, John Bowley, Monica Rohwer, Erik Oberg, Kelly Willemssens, Wendy Wintersteen, Robert K.D. Peterson, Leon G. Higley

School of Natural Resources: Faculty Publications

Yellowstone National Park thermal features regularly discharge various heavy metals and metalloids. These metals are taken up by microorganisms that often form mats in thermal springs. These microbial mats also serve as food sources for invertebrate assemblages. To examine how heavy metals move through insect food webs associated with hot springs, two sites were selected for this study. Dragon-Beowulf Hot Springs, acid-sulfate chloride springs, have a pH of 2.9, water temperatures above 70 ^oC, and populations of thermophilic bacterial, archaeal, and algal mats. Rabbit Creek Hot Springs, alkaline springs, have a pH of up to 9, some water temperatures …

Parallels Of Quantum Superposition In Ecological Models: From Counterintuitive Patterns To Eco-Evolutionary Interpretations Of Cryptic Species, David G. Angeler, Hannah B. Fried-Petersen

School of Natural Resources: Faculty Publications

Background Superposition, i.e. the ability of a particle (electron, photon) to occur in different states or positions simultaneously, is a hallmark in the subatomic world of quantum mechanics. Although counterintuitive at first sight, the quantum world has potential to inform macro-systems of people and nature. Using time series and spatial analysis of bird, phytoplankton and benthic invertebrate communities, this paper shows that superposition can occur analogously in redundancy analysis (RDA) frequently used by ecologists.

Results We show that within individual ecosystems single species can be associated simultaneously with different orthogonal axes in RDA models, which suggests that they operate in …

Current Challenges And Future Of Agricultural Genomes To Phenomes In The Usa, C. K. Tuggle, J. L. Clarke, B. M. Murdoch, E. Lyons, N. M. Scott, B. Benes, J. D. Campbell, H. Ching, C. L. Daigle, S. D. Choudhury, J.C. M. Dekkers, J.R.R. Dorea, D. S. Erti, B. O. Fragomeni, J. E. Fulton, C. R. Guadagno, D. E. Hagen, A. S. Hess, L. M. Kramer, C. J. Lawrence-Dill, A. E. Lipka, T. Lubberstedt, F. M. Mccarthy, P. S. Schnable

School of Natural Resources: Faculty Publications

No abstract provided.

Identifying Untapped Legal Capacity To Promote Multi‑Level And Cross‑Sectoral Coordination Of Natural Resource Governance, Nicola Harvey, Ahjond Garmestani, Craig R. Allen, Anoeska Buijze, Marleen Van Rijswick

School of Natural Resources: Faculty Publications

Natural resource governance in the face of climate change represents one of the seminal challenges of the Anthropocene. A number of innovative approaches have been developed in, among others, the fields of ecology, governance, and sustainability sciences for managing uncertainty and scarcity through a coordinated approach to natural resource governance. However, the absence of an enabling legal and regulatory framework has been identified in the literature as one of the primary barriers constraining the formal operationalization of these governance approaches. In this paper, we show how these approaches provide tools for analyzing procedural mandates across governmental levels and sectors in …

High-Altitude Adaptation Is Accompanied By Strong Signatures Of Purifying Selection In The Mitochondrial Genomes Of Three Andean Waterfowl, A. M. Graham, P. Lavretsky, R. E. Wilson, K. G. Mccracken

School of Natural Resources: Faculty Publications

No abstract provided.

Implementing Interdisciplinary Sustainability Education With The Food-Energy-Water (Few) Nexus, C. B. Romulo, S. Venkataraman, S. Caplow, S. Ajgaonkar, C. R. Allen, A. Anandhi, S. W. Anderson, C. B. Azzarello, K. Brundiers, E. Blavascunas, J. M. Dauer, D. L. Druckenbrod, E. Fairchild, L. R. Horne, K. Lee, M. Mwale, J. Mischler, E. Pappo, N. S. Patel, N. D. Sintov, C. S. Ramsdell, S. G. Vincent

School of Natural Resources: Faculty Publications

No abstract provided.

Habitat Characteristics, Distribution, And Abundance Of Cicindelidia Haemorrhagica (Leconte) (Coleoptera: Cicindelidae) In Yellowstone National Park, K. A. Willemssens, J. L. Bowley, L. Cavallini, E. Oberg, R.K.D. Peterson, Leon G. Higley

School of Natural Resources: Faculty Publications

No abstract provided.

Long-Term Croplands Water Productivity In Response To Management And Climate In The Western Us Corn Belt, M. Khorchani, Tala Awada, M. Schmer, V. Jin, G. Birru, S.R.S. Dangal, Andrew E. Suyker, A. Freidenreich

School of Natural Resources: Faculty Publications

No abstract provided.

15-Yr Biomass Production In Semiarid Nebraska Sandhills Grasslands: Part 1—Plant Functional Group Analysis, B. Zhao, B. M. Stephenson, T. Awada, J. Volesky, B. Wardlow

School of Natural Resources: Faculty Publications

No abstract provided.

Dynamic Rates Of Freshwater Drum Near The Northern Extent Of Their Range: Evidence Of Environment-Recruitment Relationships, M. Stuart, N. Kludt, M. A. Pegg, F. Montesanto, C. Lyon, C. J. Chance-Ossowski

School of Natural Resources: Faculty Publications

No abstract provided.

Recent Beak Evolution In North American Starlings After Invasion, Julia M. Zichello, Shelagh T. Deliberto, Paul Shrewsbury, Agnieszka A. Pierwola, Scott J. Werner

United States Department of Agriculture Wildlife Services: Staff Publications

European starlings are one of the most abundant and problematic avian invaders in the world. From their native range across Eurasia and North Africa, they have been introduced to every continent except Antarctica. In 160 years, starlings have expanded into different environments throughout the world, making them a powerful model for understanding rapid evolutionary change and adaptive plasticity. Here, we investigate their spatiotemporal morphological variation in North America and the native range. Our dataset includes 1,217 specimens; a combination of historical museum skins and modern birds. Beak length in the native range has remained unchanged during the past 206 years, …