Earth Sciences Commons^™

Characterizing Paleoenvironmental/Paleoclimatic Change Across The Permian-Triassic Boundary In The Terrestrial, High Southern Paleolatitudes: A Multiproxy Approach From The Bowen Basin, Queensland, Australia, Katarina N. Savatic

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Research shows that severe climatic perturbations, especially in the case of the worst ecosystem collapse of the Phanerozoic, the end-Permian extinction (EPE), have different spatial expressions across the globe. Using an integrated sedimentological and geochemical approach, this study from the Bowen Basin in Queensland, Australia provides a southern, high paleolatitude, stratigraphically-complete, terrestrial perspective across the Permian-Triassic boundary (PTB) that challenges previous interpretations. Analysis from this investigation allow for paleoclimatic and paleoenvironmental assessments to be made to (1) better understand the depositional environments at this time through drillcore analysis, (2) characterize the elemental signatures of mudrocks, and (3) identify the globally …

Agate Fossil Beds National Monument, Paleontological Resources Management Plan (Public Version), Scott Kottkamp, Vincent L. Santucci, Justin S. Tweet, Jessica De Smet, Ellen Stark

United States National Park Service: Publications

Executive Summary

Since Agate Springs Ranch was founded by James H. Cook in 1887, exquisite examples of transitional Miocene mammalian fauna have been found along this stretch of the Niobrara River valley. Collectively these paleontological discoveries, along with the existing archeological and historical Native American collection, were the basis for establishing Agate Fossil Beds National Monument (AGFO) as a unit of the National Park System (NPS). The fossil remains from the Harrison and Anderson Ranch formations span a short, but important, time period within the Miocene Epoch. AGFO has provided science with an intimate look into North American mammalian evolution …

Evaluating Airsoft Electric Guns For Control Of Invasive Brown Treesnakes, Adam J. Knox, Björn Lardner, Amy Yackel Adams, Robert N. Reed

United States Geological Survey: Staff Publications

Firearms are often used in lethal control of invasive vertebrates, but safety and regulatory aspects limit the circumstances under which they can be used. During August 2016 at the Brown Treesnake Project laboratory on Guam, we evaluated hobby‐grade Airsoft Electric Guns (AEGs; a lower powered, less‐hazardous, and less‐regulated alternative to firearms) for capture and control of small animals, with specific emphasis on invasive brown treesnakes (Boiga irregularis). Tests of AEGs differing in power with ammunition (plastic pellets) masses ranging from 0.20 to 0.39 g, fired at gelatin blocks from distances of 4, 8, and 12 m, showed that …

Development And Performance Assessment Of An Integrated Vermifiltration Based Treatment System For The Treatment Of Feedlot Runoff, Rajneesh Singh, Matteo D'Alessio, Yulie Meneses, Shannon L. Bartelt-Hunt, Brian Woodbury, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

The objective of this study was to treat feedlot runoff by developing an ecologically sustainable, affordable, and resilient treatment system having a relatively long life span. Three horizontal flow soil biofilters were utilized in this study: 1) without earthworms and plants (Biofilter (BF)), 2) with earthworms only (Vermifilter (VF)), and 3) with earthworms and plants (Macrophyte Assisted Vermifilter (MAVF)). The experiments were conducted with a hydraulic retention time of four days using Lumbricus terestrris earthworms and Carex frankii wetland plants. The average COD removal from the BF, VF, and MAVF were 23.2–30.4%, 61.4–69.1%, and 68.3–78.1%, respectively. Average TN removal efficiencies …

Using Climate To Explain And Predict West Nile Virus Risk In Nebraska, Kelly Helm Smith, Andrew J. Tyre, Jeff Hamik, Michael J. Hayes, Yuzhen Zhou, Li Dai

National Drought Mitigation Center: Faculty Publications

We used monthly precipitation and temperature data to give early warning of years with higher West Nile Virus (WNV) risk in Nebraska. We used generalized additive models with a negative binomial distribution and smoothing curves to identify combinations of extremes and timing that had the most influence, experimenting with all combinations of temperature and drought data, lagged by 12, 18, 24, 30, and 36 months. We fit models on data from 2002 through 2011, used Akaike's Information Criterion (AIC) to select the best‐fitting model, and used 2012 as out‐of‐sample data for prediction, and repeated this process for each successive year, …

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 …

Climate Change And Market-Based Insurance Feedbacks, Eric R. Holley, Adam Liska, Cory Walters, Geoffrey C. Friesen, Michael Hayes, Max J. Rudolph, Donald A. Wilhite

Adam Liska Papers

Climatic events have accounted for 91% of $1.05 trillion in insured costs for global catastrophic events from 1980 to 2016. Costs are driven by socio-economic development and increased frequency and severity of climatic disasters driven by climate change. Government policies to reduce systemic risk (e.g., cap-and-trade, carbon tax) have been a predominant approach for mitigation and adaptation. Alternatively, market-based incentives for climate change adaptation and mitigation already operate via the insurance industry to lessen impacts on society. Insurance feedbacks include changes in 1) premiums and insurance policies, 2) non-coverage, and 3) policy making and litigation. Alongside government policies, insurance feedbacks …

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 …

Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas

United States Fish and Wildlife Service: Publications

Dear Colleague Letter from the American Fisheries Society to fellow scientific societies, July 25, 2020, about the urgent need for responsive collective action to mitigate impending radical climate change. Includes the Statement of World Aquatic Scientific Societies on the Need to Take Urgent Action Against Human-Caused Climate Change, Based on Scientific Evidence, emphasizing the importance of aquatic ecosystems. Includes extensive citations and notes.

"Water is the most important natural resource on Earth as it is vital for life. Aquatic ecosystems, freshwater or marine, provide multiple benefits to human society, such as provisioning of oxygen, food, drinking water, genetic resources; regulation …

Early Paleogene Biosiliceous Sedimentation In The Atlantic Ocean: Testing The Inorganic Origin Hypothesis For Paleocene And Eocene Chert And Porcellanite, Jakub Witkowski, Donald E. Penman, Karolina Bryłka, Bridget S. Wade, Sabine Matting, David M. Harwood, Steven M. Bohaty

Department of Earth and Atmospheric Sciences: Faculty Publications

The widespread occurrence of lower Eocene chert and porcellanite has been viewed as a major paleoceanographic issue since the advent of ocean drilling, and both biotic and abiotic forcings have been proposed to explain it. We present a reconstruction of indurated siliceous sediment (ISS) and preserved biosiliceous sediment (PBS) occurrences in the Atlantic Ocean through the Paleocene and Eocene (~66 through 34 Ma). ISS and PBS distributions reveal dissimilar temporal trends, with the peak of ISS occurrences coinciding with the Early Eocene Climatic Optimum, in line with previous studies. PBS occurrences show a generally increasing trend culminating between 44 and …

Legacy And Current Pesticide Residues In Syr Darya, Kazakhstan: Contamination Status, Seasonal Variation And Preliminary Ecological Risk Assessment, Daniel D. Snow, P. Chakraborty, B. Uralbekov, B. Satybaldiev, J. Brett Sallach, L. M. Thornton Hampton, M. Jeffries, A. S. Kolok, Shannon L. Bartelt-Hunt

Nebraska Water Center: Faculty Publications

The Syr Darya is one of two major rivers in Central Asia supplying critical fresh water to the Aral Sea. In spite of the river’s importance and agriculturally-intensive history, few studies have provided a modern evaluation of and the occurrence of pesticide residues potential effects to aquatic life. The primary goal of this investigation was to determine seasonal variations in ambient concentrations of modern and legacy pesticides in bottom sediment and water of the Syr Darya in Kazakhstan (KZ) downstream from an agriculturally-intensive watershed in Uzbekistan. Grab samples and passive samplers were used at five remote sampling stations during June …

Monitoring Residual Soil Moisture And Its Association To The Long-Term Variability Of Rainfall Over The Upper Blue Nile Basin In Ethiopia, Getachew Ayehu, Tsegaye Tadesse, Berhan Gessesse

National Drought Mitigation Center: Faculty Publications

Monitoring soil moisture and its association with rainfall variability is important to comprehend the hydrological processes and to set proper agricultural water use management to maximize crop growth and productivity. In this study, the European Space Agency’s Climate Change Initiative (ESA CCI) soil moisture product was applied to assess the dynamics of residual soil moisture in autumn (September to November) and its response to the long-term variability of rainfall in the Upper Blue Nile Basin (UBNB) of Ethiopia from 1992 to 2017. The basin was found to have autumn soil moisture (ASM) ranging from 0.09–0.38 m³/m³, …

Using The Electromagnetic Induction Survey Method To Examine The Depth To Clay Soil Layer (Bt Horizon) In Playa Wetlands, Yuan Xue, Zhenghong Tang, Qiao Hu, Jeff Drahota

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

Purpose Sediment accumulation has been and continues to be a significant threat to the integrity of the playa wetland ecosystem. The purpose of this study was to determine the vertical depth to the clay soil layer (Bt horizon) and thus to calculate the thickness of sediments accumulated in playa wetlands.

Materials and methods This study used the electromagnetic induction (EMI) survey method, specifically EM38-MK2 equipment, to measure the vertical depth to the clay soil layer at the publicly managed wetlands in the Rainwater Basin, Nebraska, USA.

Results and discussion The results indicated that the depth to the clay soil layer …

Droughtscape, Summer 2020, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

DroughtScape, Summer 2020

Characterizing Peridotite Xenoliths From Southern Vietnam: Insight Into The Underlying Lithospheric Mantle, Kirby Hobbs

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Extrusion tectonics has been invoked to explain the extensive basaltic magmatism that has erupted over Indochina within the last 17 Ma. The basalts display two-stage eruptive cycles consisting of tholeiites followed by alkaline basalts. Lithospheric mantle xenoliths recently sampled from the alkaline basalts of two volcanic centers, Pleiku and Xuan Loc, primarily consist of fertile spinel lherzolites, and Xuan Loc also contains refractory spinel harzburgites. We measured major elements in xenolith mineral separates, trace elements in clinopyroxenes and orthopyroxenes, and Pb-Sr-Nd isotopic compositions in clinopyroxenes to determine the origin and history of the subcontinental lithospheric mantle (SCLM) beneath Vietnam. Most …

Soil Chemical Properties After 12 Years Of Tillage And Crop Rotation, Maysoon M. Mikha, Gary Hergert, Xin Qiao, Bijesh Maharjan

Panhandle Research and Extension Center

Crop rotation in combinationwith tillage can improve productivity, enhance economical return, and reduce soil erosion. The objective of this study was to evaluate the impact of moldboard plow (MP), strip tillage (ST), no-tillage (NT), and crop rotations on: (1) crop yield; (2) soil chemical properties; and (3) particulate organic matter (POM). The study was initiated in 2007 at the University of Nebraska-Lincoln Panhandle Research and Extension Center near Scottsbluff, NE. Crops in rotation were corn (C; Zea mays L.) and dry bean (DB; Phaseolus vulgaris L.) organized in a 3-yr rotation (C–DB–C) and a 4-yr rotation with the addition of …

Climate Change Impacts The Subsurface Transport Of Atrazine And Estrone Originating From Agricultural Production Activities, Renys Enrique Barrios, Simin Akbariyeh, Chuyang Liu, Khalid Muzamil Gani, Margarita T. Kovalchuk, Xu Li, Yusong Li, Daniel D. Snow, Zhenghong Tang, John Gates, Shannon L. Bartelt-Hunt

Nebraska Water Center: Faculty Publications

Climate change will impact soil properties such as soil moisture, organic carbon and temperature and changes in these properties will influence the sorption, biodegradation and leaching of trace organic contaminants to groundwater. In this study, we conducted a modeling case study to evaluate atrazine and estrone transport in the subsurface under current and future climate conditions at a field site in central Nebraska. According to the modeling results, in the future, enhanced evapotranspiration and increased average air temperature may cause drier soil conditions, which consequently reduces the biodegradation of atrazine and estrone in the water phase. On the other hand, …

Combined Use Of Sentinel‐1 Sar And Landsat Sensors Products For Residual Soil Moisture Retrieval Over Agricultural Fields In The Upper Blue Nile Basin, Ethiopia, Getachew Ayehu, Tsegaye Tadesse, Berhan Gessesse, Yibeltal Yigrem, Assefa M. Melesse

National Drought Mitigation Center: Faculty Publications

The objective of this paper is to investigate the potential of sentinel‐1 SAR sensor products and the contribution of soil roughness parameters to estimate volumetric residual soil moisture (RSM) in the Upper Blue Nile (UBN) basin, Ethiopia. The backscatter contribution of crop residue water content was estimated using Landsat sensor product and the water cloud model (WCM). The surface roughness parameters were estimated from the Oh and Baghdadi models. A feed‐forward artificial neural network (ANN) method was tested for its potential to translate SAR backscattering and surface roughness input variables to RSM values. The model was trained for three inversion …

A Hydrometeorological Assessment Of The Historic 2019 Flood Of Nebraska, Iowa, And South Dakota, Paul Xavier Flanagan, Rezaul Mahmood, Natalie Umphlett, Erin M.K. Haacker, Chittaranjan Ray, Bill Sorensen, Martha Shulski, Crystal J. Stiles, David Pearson, Paul Fajman

High Plains Regional Climate Center: Staff Publications

During early 2019, a series of events set the stage for devastating floods in eastern Nebraska, western Iowa, and southeastern South Dakota. When the floodwaters hit, dams and levees failed, cutting off towns, while destroying roads, bridges, and rail lines, further exacerbating the crisis. Lives were lost and thousands of cattle were stranded. Estimates indicate that the cost of the flooding has topped $3 billion as of August 2019, with this number expected to rise.

After a warm and wet start to winter, eastern Nebraska, western Iowa, and southeastern South Dakota endured anomalously low temperatures and record-breaking snowfall. By March …

What Is The Limiting Nutrient In Winter In Urban Reservoirs? A Case Study, Precious Nyabami

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The importance of reservoirs in widely acknowledged by urban population, yet little is understood scientifically about their ability to process nutrients deposited into them in winter. Nutrients in waste water, lawns and construction runoff are deposited into reservoirs and several ecosystem services are lost which leads to what several researchers call “the urban syndrome”. Some studies have been done on the winter limnology of lakes, yet little is understood about the same process in reservoirs. To fill this missing knowledge gap, a study on one of Nebraska’s lakes (Holmes’ lake) was done. In this study, we simulated how phosphorus, nitrogen …

Building Adaptive Capacity In Tribal Communities Of The Missouri River Basin To Manage Drought And Climate Extremes: A Case Study From The Wind River Indian Reservation, Crystal J. Stiles, Natalie Umphlett, Mitch Cottenoir

High Plains Regional Climate Center: Staff Publications

Native American peoples of the Northern and Central Plains have long endured harsh climate conditions, such as floods and droughts, and they possess valuable traditional knowledges that have enhanced their resilience to these extreme events. However, in recent times, limited capacity to adapt to a rapidly changing climate combined with a lack of resources have increased tribes’ vulnerability to climate extremes and their associated impacts. In response, a number of projects have been developed to assist tribes with their self-identified climate- and drought-related needs, particularly in the context of on-reservation decision-making. In this case study, we present an engagement strategy …

Impact Of Agricultural Land Use On Stream Nitrate, Phosphorus, And Sediment Concentrations At The Watershed And Field Scale, Brittany A. Kirsch

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Water quality is directly impacted by the landscape through which it travels. As such, land use, including summer annual and winter annual/perennial agriculture, has dramatic influence on the water quality of downstream aquatic and terrestrial ecosystems. I examined the impact of agricultural land use on water quality through two projects, one at a watershed scale and one at a field scale. In my first project, I investigated the impact of agricultural land use and climate on water quality in 13 HUC10 watersheds across Nebraska using public data from US Geological Survey (USGS), US Department of Agriculture National Agricultural Statistics Service …

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 …

Adjusting The Lens Of Invasion Biology To Focus On The Impacts Of Climate-Driven Range Shifts, Piper D. Wallingford, Toni Lyn Morelli, Jenica M. Allen, Evelyn M. Beaury, Dana M. Blumenthal, Bethany A. Bradley, Jeffrey S. Dukes, Regan Early, Emily J. Fusco, Deborah E. Goldberg, Inés Ibáñez, Brittany B. Laginhas, Montserrat Vilà, Cascade J.B. Sorte

United States Geological Survey: Staff Publications

As Earth’s climate rapidly changes, species range shifts are considered key to species persistence. However, some range-shifting species will alter community structure and ecosystem processes. By adapting existing invasion risk assessment frameworks, we can identify characteristics shared with high-impact introductions and thus predict potential impacts. There are fundamental differences between introduced and range-shifting species, primarily shared evolutionary histories between range shifters and their new community. Nevertheless, impacts can occur via analogous mechanisms, such as wide dispersal, community disturbance and low biotic resistance. As ranges shift in response to climate change, we have an opportunity to develop plans to facilitate advantageous …

Remediation Strategies To Reduce Heavy Metal Uptake In Lettuce Grown In Contaminated Urban Soil, Ryley Thomas

UCARE: Research Products

Urban soils are increasingly used to produce food for local consumption, which requires at the same time management strategies that prevent the plant uptake of potentially present contaminants. This study was conducted to test different soil amendments for their ability to retain lead (Pb) and arsenic (As) within the soil matrix. The analyzed soil was taken from a potential community garden lot near a railroad in Lincoln, NE where elevated concentrations in Pb and As had been detected. Ponderosa pine biochar and spent coffee grounds were used as soil additives because of their documented chemical reactivity towards soil cations or …

Sediment Outflow Under Simulated Rainfall Conditions With Varying Geotechnical Properties, Pranjay Joshi, Akhilesh Kumar, P. V. Singh, Jahangeer Jahangeer

Daugherty Water for Food Global Institute: Faculty Publications

The vulnerability of soil toward erosion might be reduced by having a good vegetative cover over the soil surface, slope improvement, and improving soil properties so that it is not easily detached and transported. However, the establishment of proper vegetative cover is a long process because it takes time for seeds to germinate and attain maturity. As an alternative approach, if soil resistance was increased by increasing the shear strength of soil against erosive forces offered by eroding agents, the soil system would become capable of withstanding the detachment of its particles on the application of shear stress. To achieve …

Increased Drought Severity Tracks Warming In The United States’ Largest River Basin, Justin T. Martin, Gregory T. Pederson, Connie A. Woodhouse, Edward R. Cook, Gregory J. Mccabe, Kevin J. Anchukaitis, Erika K. Wise, Patrick J. Erger, Larry Dolan, Marketa Mcguire, Subhrendu Gangopadhyay, Katherine J. Chase, Jeremy S. Litell, Stephen T. Gray, Scott St. George, Jonathan M. Friedman, David J. Sauchyn, Jeannine-Marie St-Jacques, John King

United States Geological Survey: Staff Publications

Across the Upper Missouri River Basin, the recent drought of 2000 to 2010, known as the “turn-of-the-century drought,” was likely more severe than any in the instrumental record including the Dust Bowl drought. However, until now, adequate proxy records needed to better understand this event with regard to long-term variability have been lacking. Here we examine 1,200 y of streamflow from a network of 17 new tree-ring–based reconstructions for gages across the upper Missouri basin and an independent reconstruction of warm-season regional temperature in order to place the recent drought in a long-term climate context. We find that temperature has …

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 …