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Spatio-Temporal Analysis Of Human-Carnivore Conflict In The Tarangire-Manyara Ecosystem, Tanzania, Sophie Carpenter

Environmental Studies Honors Projects

Livestock depredation by large carnivores significantly threatens human livelihoods across the globe, with severe ecological and socioeconomic implications. Economic costs of livestock depredation impact the tolerance for carnivores among communities living alongside wildlife, often straining human-carnivore coexistence. Using geographic and temporal attributes from livestock depredation records (n=406) collected between 2004 and 2023, we identified spatiotemporal patterns of depredation by African lions, leopards, and spotted hyenas in the Tarangire-Manyara Ecosystem in northern Tanzania. We found significant interactive relationships between the number of attacks reported and the season, time, and site of attack; with these interactions differing between the carnivores. To better …

Large Mammal Herbivores As Gardeners Of Tropical Forest Ecosystems, Kathryn Garner

Student Scholarship

Ecosystems worldwide are experiencing changes in structure and function as populations of fauna decline and experience local extinctions (Torres-Romero et al. 2020). Due primarily to their body size, large mammal herbivores (LMHs) are disproportionately prone to extinction from human activities such as agricultural expansion, deforestation, and anthropogenic climate change (Pringle et al. 2023). Additionally, as the number of domesticated LMHs (i.e. cattle, pigs, etc.) continue to increase in both density and distribution, their wild counterparts are continually displaced, resulting in increased competition for resources and an increased risk of disease transmission between domestic to wild species (Pringle et al. 2023; …

Examining Sustainable And Regenerative Viticultural Practices In The Rheinhessen Wine Region Of Germany, Claire Hoffmann

CISLA Senior Integrative Projects

No abstract provided.

Environmental And Societal Impacts Of Agricultural Land Abandonment In Indonesia: A Bibliometric Review, Jane A. Landrum

Geosciences Undergraduate Honors Theses

In the past decades, Southeast Asia has faced one of the highest urbanization rates globally, with land conversion, agricultural land abandonment, and deforestation occurring simultaneously. High population growth rates and migration away from rural areas have also led to increased food insecurity, which has increased the need for agricultural production. In Indonesia, high rates of urbanization on the island of Java have historically prompted governmental policy solutions aimed at population redistribution and agricultural extensification (rather than intensification). The cost of this conversion of lands to agriculture often falls on the environment, with peatlands and forested lands being converted to large-scale …

Assessing Biochar And Industrial Hemp To Remediate Heavy-Metal-Contaminated Soil, Sophie W. Sward

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Environmental degradation is becoming increasingly prevalent as global industrialization runs rampant. Anthropogenic activity, such as mining, deposits inorganic pollutants into the environment, leading to potential soil and water contamination. Traditional, engineering-based remediation and containment procedures alter soil structure and aggregate stability and affect the biological function of the area impacted by mining activities. Phytoremediation is a more energy-efficient, and therefore cost-effective, method of environmental restoration. Phytoremediation, on its own, works in soils that are less contaminated so that the selected plant can actually grow. Soil amendments, such as biochar, can be added to improve remediation potential in more contaminated soils. …

Toxicity And Biodegradability Of Novel Boronium Vs Conventional Ammonium Based Anti Microbial Compounds In Wastewater Treatment Systems, Noor Shalan

Poster Presentations

Quaternary ammonium compounds (QACs) are highly effective as disinfectants, herbicides, and pesticides; thus, overuse causes elevated levels of residual toxicity in domestic and industrial wastewater. QACs can be toxic to essential bacteria breaking down pollutants in wastewater treatment plants (WWTPs) and can remain untreated in effluent, harming the environment, and contributing to antibiotic resistance, posing risks to human health. Novel boronium-based antimicrobial compounds have demonstrated efficacy in eliminating bacteria, fungi, and viruses. If the boronium compounds exhibit lower residual toxicity, they could offer a promising alternative to QACs. Because these compounds are still in development, their potential toxicity to the …

Ghosts In Glass: Ghost Crabs (Ocypode Quadrata) As Judges Of Glass Sand For Coastal Restoration, Emily Parrish

Poster Presentations

Coastal erosion is heavily impacting coastal ecosystems across the Gulf. For instance, the state of Louisiana loses a football field worth of land every 100 minutes (Couvillion, 2017). The drastic loss of coastline highlights the dire need for restoration in the Northern Gulf Coast. An unexpected solution to this sediment loss may solve two major environmental issues at once by diverting millions of tons of glass waste from entering America’s landfills each year. By crushing glass to create sand and gravel for coastal restoration, we may generate a consistent and sustainable source of substrate. Our goal is to determine the …

Monitoring The Qosh Tepa Canal Project: A Geospatial Timeline Of Taliban Water Diversion, Enerel L. Crosslin

Honors Thesis

The World Food Program states that “acute malnutrition in Afghanistan is above emergency thresholds in 25 out of 34 provinces and is expected to worsen”. Aiming to support agriculture, the Taliban began to build the 285 km “Qosh Tepa Canal” to divert 17% of the Amu Darya, which supports the livelihoods of millions of people in downstream Uzbekistan and Turkmenistan. The World Bank estimated that roughly 2.4 million Central Asians could become climate refugees by 2050. Our objectives are to create a timeline of satellite imagery of the canal’s construction. Our research questions are (1) Can we characterize water diversion …

Biodegradable Active Packaging: Exploring The Antimicrobial Efficacy And Compostability Of Chitosan-Based Films, Rachel Mchugh

All Theses

The overarching purpose of this experiment is to create an active packaging component that has both antimicrobial and biodegradable properties specifically designed for poultry food products. For the scope of this study, the packaging component created would theoretically be used in conjunction with another material, such as a poultry tray which are commonly used for fresh poultry products. Based on the scope and purpose of this experiment, biopolymer films and coatings were considered after the initial literature review. Due to the goals of the packaging component, chitosan, a polysaccharide shown to have antimicrobial properties and an inherent ability to biodegrade, …

Electrochemically Precipitated Struvite Effects On Extractable Soil Nutrients, Owen Collins

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Struvite recovery from wastewater streams may provide an alternative to traditional fertilizer-phosphorus (P) sources, while also providing the benefit of reducing nitrogen and P loads in wastewater effluent and reducing effects of eutrophication in surface waters. Limited research has been conducted to assess the effects of struvite fertilization on concentrations of soil micronutrients and potassium (K) compared to other traditional fertilizer-P sources in historically agricultural soils. The objective of this study was to assess the effects of fertilizer-P source (i.e., synthetically produced electrochemically precipitated struvite [ECST], chemically precipitated struvite [CPST], monoammonium phosphate [MAP], diammonium phosphate [DAP], triple superphosphate [TSP], rock …

Reevaluating The Role Of Ruppia Maritima: Recruitment Dynamics And Habitat Use By Blue Crabs (Callinectes Sapidus) And Associated Benthic Fauna In A Mid-Atlantic Seagrass Community, Delaney St. Pierre

Theses, Dissertations and Culminating Projects

The value of seagrasses as essential fish habitat is well recognized, but limited data exist on the value of one particular species, Ruppia maritima (widgeon grass), as habitat for fish and invertebrates. During the summer of 2024, I evaluated R. maritima, Zostera marina (eelgrass) and mixed beds to assess their relative value as habitat in Barnegat Bay, New Jersey. Results from throw traps indicated significant monthly differences for pipefish, gobies, blue crabs, grass shrimp, and sand shrimp, driven by active recruitment events. When evaluating habitat type, we found no taxa that were significantly more abundant in Z. marina habitat as …

Thermal Biology Of The Eastern Treehole Mosquito Aedes Triseriatus (Diptera: Culcidae) And Other Vertivorous Dipterans, Kelly I. Zimmerman

Theses, Dissertations and Culminating Projects

Temperature plays a critical role in mosquito life cycle, behavior, and other ecological interactions. My dissertation analyzed how temperature affects egg hatch rates of the eastern treehole mosquito (Aedes triseriatus) and how amino acid substitutions in TRPA1 correlated with host finding through thermotaxis and the convergent evolution of vertebrate feeding/utilizing in Dipterans. As ectotherms, embryonic development and egg hatch rates are directly influenced by the water temperature mosquito eggs are oviposited into. Ae. triseriatus eggs do not hatch all at once, to avoid potentially high larval mortality rates due to their non-static oviposition sites. They engage in staggered egg hatching, …

Mitigating Nitrogen Losses: The Role Of Enhanced Efficiency Fertilizers In Sustainable Corn Production, Dipesh Giri

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

Nitrogen (N) is essential for crop production, but its inefficient use often leads to environmental losses through nitrate leaching, ammonia volatilization, and nitrous oxide (N₂O) emissions. Enhanced efficiency fertilizers (EEFs), such as nitrification inhibitors (NIs) and urease inhibitors (UIs), have been developed to minimize these losses and improve nitrogen use efficiency (NUE). This research combined a multi-year field experiment and a controlled laboratory study to evaluate how dual-inhibitor fertilizers compare to conventional urea and single-inhibitor formulations in Nebraska cropping systems. The main objective was to understand how nitrogen inhibitors influence N availability, crop performance, and nitrogen losses across different environmental …

Extending Cover Crop Growing Window To Improve The Health Of Environmentally Sensitive Soils, Noshin Ara Tunazzina

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

Sloping and sandy soils are highly susceptible to degradation. The health of these soils could be improved with cover crops (CCs). However, CC effectiveness in improving soil health mainly depends on CC biomass production, which is often low in temperate regions. The question is: how can we increase CC biomass production? Lengthening the CC growing window can be a potential strategy. This study assessed how 1) interseeded and terminated early (2-3 weeks before crop planting) CC, 2) interseeded and terminated late (at crop planting) CC, 3) drilled (after harvest) and terminated early CC, 4) drilled and terminated late CC, and …

Assessment Of Lake Salvador Shoreline Dynamics To Support Restoration Of Submerged Aquatic Vegetation In Jean Lafitte National Historical Park And Preserve, Louisiana, Lydia V. Dipaola

LSU New Orleans Theses and Dissertations

High wave energy degrades shoreline habitat between Lake Salvador and Jean Lafitte National Historical Park and Preserve (JELA), Louisiana. JELA constructed a northern breakwater in 2004, and a southern breakwater in 2024 to protect the shoreline and promote restoration of submerged aquatic vegetation (SAV). This study analyzes Sentinel-2 imagery to quantify coastal loss along the JELA-Lake Salvador using the Change Polygon Approach, assessing annual, cumulative and major storm event-associated shoreline changes for January 2017-2025. SAV cover, nekton diversity, wave energy, and turbidity were measured before-and-after southern breakwater construction to monitor ecological and environmental outcomes. The JELA-Lake Salvador shoreline has lost …

Toxicity And Biodegradability Of Novel Boronium Vs Conventional Ammonium-Based Antimicrobial Compounds In Wastewater Treatment Systems, Noor Shalan

Honors Theses

Quaternary ammonium compounds (QACs) are highly effective as disinfectants, herbicides, and pesticides; thus, overuse causes elevated levels of residual toxicity in domestic and industrial wastewater. QACs can be toxic to essential bacteria breaking down pollutants in wastewater treatment plants (WWTPs) and can remain untreated in effluent, harming the environment, and contributing to antibiotic resistance, posing risks to human health. Novel boronium-based antimicrobial compounds have demonstrated efficacy in eliminating bacteria, fungi, and viruses. If the boronium compounds exhibit lower residual toxicity, they could offer a promising alternative to QACs. Because these compounds are still in development, their potential toxicity to the …

Ghosts In Glass: Ghost Crabs As Judges Of Glass Sand For Coastal Restoration, Emily Parrish

Honors Theses

Over 60% of the Gulf of Mexico coastline is actively eroding, which has resulted in thousands of miles of lost coastline over the last 100 years. This drastic loss of coastal land highlights the dire need for coastal restoration across the entirety of the Gulf Coast. A vital aspect of restoring these eroded areas is replenishing eroded substrate, traditionally conducted through offshore dredging of substrates which comes with high economic and ecological costs. Recycled glass sand may be able to fill this role and reduce our reliance on dredging while lowering the amount of glass waste entering landfills each year. …

A Herpetofaunal Inventory Study Of Two National Wildlife Refuges In The Mississippi Delta And Associated Evaluation Of Trapping Efficacy, Andrew Holzinger

Master's Theses

The objectives of this project were to record the diversity and distribution of amphibian and reptile species present at Panther Swamp and Hillside National Wildlife Refuges (NWR) and to quantify trapping efficacy as a result of various methodologies under different habitat variables. The primary methods employed were two varieties of drift fence trap arrays consisting of 100-foot sections of silt fencing with buried 2.5-gallon buckets as pitfall traps and box traps placed at the end of each fence to capture larger organisms. When conditions permitted, aquatic trapping was also employed across the Refuges. A total of 55 species were documented, …

Comparison Of Rt-Qpcr And Rt-Ddpcr On Assessing Model Virus In Wastewater, Wafa Youssfi

Graduate Theses and Dissertations

There is an increasing demand for quantifying viral loads in diverse wastewater systems using polymerase chain reaction (PCR). This study evaluates the performance of two commonly used workflows: reverse transcription quantitative PCR (RT-qPCR) and reverse transcription droplet digital PCR (RT-ddPCR) in wastewater. We compared the two methods by measuring the viral ribonucleic acid (RNA) of a model virus Phi6 in samples collected from various treatment stages at the Westside Wastewater Treatment Facility in Fayetteville, AR. RNA was extracted from real and synthetic wastewater samples and analyzed in parallel using both RT-qPCR and RT-ddPCR. Findings reveal that both methods demonstrated similar …

Finer Resolution Paleoclimatological Network Analysis Of Hydrological Extremes And Tree-Growth Response For Kentucky, U.S.A., Jordan Sharp

Electronic Theses and Dissertations

As climate change accelerates, southeastern states like Kentucky face increasing environmental and economic challenges. To improve future climate predictions, this study enhances paleoclimate reconstructions with a high-resolution tree-ring network for Kentucky, combining data from both living trees and dendroarchaeological sources. I evaluated the climate sensitivity of tree growth using superposed epoch analysis, static correlations, and spatial field correlations in KNMI Climate Explorer, along with moving correlations against seasonal temperature and moisture variables. Findings reveal that white oak and tulip poplar exhibit significant drought sensitivity across both live and archeological sites. However, I observed a weakening relationship between tree-ring growth and …

Pastoral Land Condition: Kimberley Land Condition Standards, Robert Sudmeyer, Rick Fletcher, Kathryn Ryan, Matthew Fletcher, Charles Martin, Philip Thomas, Karen Holmes, Karyn Reeves, Wayne Fletcher

Natural resources published reports

This report outlines the conceptual basis and quantitative land condition standards that define acceptable pastoral land condition for the Kimberley, Western Australia (WA), to meet the regulatory requirements of the Land Administration Act 1997 and the Soil and Land Conservation Act 1945.

The Department of Primary Industries and Regional Development (DPIRD) develops regional-level pastoral land condition standards for WA to implement the Framework for sustainable pastoral management – Revised edition, which is designed to address the Office of the Auditor General’s recommendations to improve the management of pastoral lands in WA. The application of these standards is expected to …

Walleye And Sauger Movement And Entrainment In Lewis And Clark Lake, William Joseph Radigan

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Walleye Sander vitreus and Sauger Sander canadensis are both socioeconomically important sportfish species in Lewis and Clark Lake, an interjurisdictionally managed mainstem Missouri River reservoir fishery. Since 2011, adult catch per unit effort (CPUE) of both Walleye and Sauger has remained at approximately 50% of pre-2011 levels. A presumed reason for the suppressed CPUE of adult Walleye and Sauger is substantial entrainment of larval and adult fish resulting from the reservoir’s high turnover rate (7.2 d). Acoustic telemetry was used to quantify adult movement and entrainment and ichthyoplankton trawls were used to assess larval entrainment. Relative importance of factors driving …

Landscape Effects On The Beneficial Arthropod Community In Agriculturally Dominated Environments, Hannah E. Stowe

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Ecosystem services in agriculturally dominated regions rely, at least in part, on arthropods. Environment and biodiversity influence beneficial arthropods in population size, community structure, diversity, and ecosystem service provisioning. Predation is among the most important services provided by arthropods in agroecosystems. Understanding what alters predation and predator activity can support the successful application of biological control and, more broadly, integrated pest management. Land use and edge adjacency, field characteristics, landscape, seasonality, and diel period all alter predatory behavior. Crop fields dominate Nebraska agroecosystems, although interspersed perennial grasslands persist through the Conservation Reserve Program (CRP). Such grasslands supply crucial resources and …

Optimizing Nitrogen Management: Assessing Nitrate Transport In The Deep Vadose Zone And Its Impact On Groundwater Quality In East-Central Nebraska, Muili O. Lawal

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Groundwater contamination by nitrate (NO₃-N) is a growing environmental and public health concern driven largely by intensive agricultural fertilizer applications. The vadose zone plays an important role in NO₃-N transport, influencing groundwater quality and agricultural sustainability. This study investigated NO₃-N leaching dynamics in the deep vadose zone of Water Quality Sub-Area 30 (WQA30) within the Lower Loup Natural Resources District (LLNRD), northeast of Columbus, Nebraska (mean groundwater NO₃-N: 20.3 mg/L), using soil cores from 16 shallow (to 6.1 m) and four deep (down to 25.9 m) across four zones, two with inorganic fertilizer (Zones 1 and 4) and two with …

Constructing An Attractive Targeted Sugar Bait For Reducing Mosquito Populations, Xi Xian Ng

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Mosquito-borne pathogen transmission continues to pose a significant burden to global public health, well-being, and economic productivity. In the absence of universally available vaccines and amidst rising insecticide resistance that leads to product failures, there is an urgent need to develop new tools to mitigate mosquito-borne disease risk. Two general strategies exist to reduce transmission risk: personal protective measures and area-wide chemical interventions. Attractive Targeted Sugar Bait (ATSB) systems leverage the sugar-feeding behavior of mosquitoes—critical for sustaining their flight, metabolism, development, and fecundity—by delivering oral toxicants through attractively formulated sugar baits. This study aimed to develop an optimized ATSB formulation …

Spatial Ecology And Predator–Prey Interactions Of Mountain Lions In California's San Francisco North Bay, Jacob A. Harvey

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

Understanding spatial ecology and predator-prey interactions are central to wildlife ecology and conservation. We tracked mountain lions with GPS telemetry to evaluate space use, predator-prey interactions, and resource selection in California’s San Francisco North Bay, USA. In Chapter 1, we evaluated the influence of human disturbance on home range size, prey composition, and kill rates on black-tailed deer (Odocoileus hemionus columbianus) across an urban-rural gradient. Both males and females increased home range size with increasing development at low to moderate levels of development, but female home range size stabilized across greater proportions of development while male home range …

Maggot Mass Effect On The Development And Survival Of Forensic Blow Flies, Akomavo Fabrice Gbenonsi

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

Forensic entomology scientists use blow flies' developing patterns to estimate the postmortem interval (PMI). However, larval aggregations produce metabolic heat, resulting in complex microclimates that may change growth timetables. This study investigates how larval density and associated temperature changes affect the development and survival of two forensically essential blow fly species, Lucilia sericata and Calliphora vicina.

This study examined how larval density and associated thermal profiles affect the development of both blow fly species. Using a split-plot design, we tested four larval densities at 25°C and 30°C, with temperature gradients measured via thermocouple at four mass positions three times …

Assessment Of Sampling Gears For Bigheaded Carp In Mid-Order Prairie Rivers In Nebraska, Brett M. Anderson

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

Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis (collectively bigheaded carp) have invaded tributaries to the Missouri River and Platte River in Nebraska, USA. Information pertaining to efficient sampling protocols for assessing bigheaded carp populations as well as benefiting removal efforts is needed. Herding is a method used to increase the capture efficiency and detection probability of adult bigheaded carp by simultaneously using active and passive sampling gears. During June-July 2023, four herding techniques were assessed regarding their ability to elicit directional movement past an enclosure gate. The combination of sound and electrofishing resulted in the highest mean …

Latitudinal Gradients In Arctic Willows And Their Effects On Stream-Riparian Systems, Donal Heaney

Honors Scholar Theses

Extreme warming in the Arctic due to climate change presents the opportunity to study rapid changes to ecosystems and their potential resilience. Willow (Salix) shrubs form the base of many Arctic riparian ecosystems, and they have increased in height and range as temperatures have warmed. The effects of warming on willows could alter riparian ecosystems and neighboring streams, so understanding how climate change will affect willows is integral to understanding how the stream-riparian meta-ecosystem might change. I used data from the EvoME Institute to compare willow canopy cover above Arctic streams along a latitudinal transect and investigate how …

Cover Crop-Induced Improvements To Soil Hydraulic Properties And The Role Of Termination Time In Mitigating Negative Soil Moisture Impacts, Fabrizio Javier Pilco

Theses and Dissertations

In the Lower Rio Grande Valley of South Texas, water scarcity and drought pose ongoing challenges for farmers. Although cover crops are promoted for improving soil health and moisture, their effects on soil hydraulic properties in this region remain understudied. This thesis addresses both long-term (Chapter 2) and short-term (Chapter 3) impacts of cover crops on soil hydraulic properties and soil moisture. Long-term effects were evaluated through a three-year participatory field trial across four farms using a BACI design, while short terms were evaluated using a complete randomized block design. Soil hydraulic properties (residual water content θr, saturated water content …