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Controlling Lonicera Maackii (Amur Honeysuckle): Basal Bark And Prescribed Fire Efficacy And Impacts, Kaleb Baker

Graduate Research Theses & Dissertations

Lonicera maackii is a non-native shrub that has invaded eastern and midwestern North American deciduous forests, altering the ecosystem functions and reducing biodiversity. Managers tasked with controlling L. maackii, being resource limited, require effective methods that are quick and easy to use without inflicting extensive nontarget damage. This study explores prescribed fire and seasonal basal applications of triclopyr as control methods and examines their extent of off-target damage. Paired-split plots were established to implement seasonal basal bark treatments within burned/unburned units where individual L. maackii were tracked to determine mortality and the hyperlocal impacts of management. Basal bark treatments were …

Preservation Protocols For Maintaining Species Stability Of Arsenic, Chromium, And Selenium In Water Samples, Contessa Lowery

Water Resources Professional Project Reports

Water quality has become an increasing concern in recent years. The environmental challenges surrounding water quality include the presence of dissolved metals and their potential impact on human health and the environment. The challenge is exacerbated because many important metals have multiple oxidation states, which affect the health and environmental behavior of the metal. Many metals are known carcinogens and increased anthropogenic effects have inexorably made metals’ accumulation an imposing threat. Analytical instrumentation has advanced in many areas, making it now possible to measure very low concentrations of multiple elements in water. Current interest is determining the chemical speciation of …

Assessment Of Two Behavioural Models (Hbm And Ranas) For Predicting Health Behaviours In Response To Environmental Threats: Surface Water Flooding As A Source Of Groundwater Contamination And Subsequent Waterborne Infection In The Republic Of Ireland, L. Andrade, K. O'Malley, Paul Hynds, E. O'Neill, J. O'Dwyer

Articles

Extreme weather events (EWEs) are increasing in frequency, posing a greater risk of adverse human health effects. As such, developing sociological and psychological based interventions is paramount to empowering individuals and communities to actively protect their own health. Accordingly, this study compared the efficacy of two established social-cognitive models, namely the Health Beliefs Model (HBM) and Risks-Attitudes-Norms-Abilities-Self-regulation (RANAS) framework, in predicting health behaviours following EWEs. Surface water flooding was used as the exemplar EWE in the current study, due to the increasing incidence of these events in the Republic of Ireland over the past decade. Levels of prior experience with …

Supply Chain Managers' Reverse Logistics Strategies To Control Cost Through Risk Mitigation, Lawrence A. Reeves

Walden Dissertations and Doctoral Studies

Supply chain managers in the food and beverage industry face significant challenges regarding the use of effective reverse logistics strategies to reduce supply chain disruptions, control risk, and reduce costs. Through the lens of resource dependence theory, the purpose of this multiple case study was to explore reverse logistics strategies used by supply chain managers in the United States to control cost through risk mitigation. Participants in this study included 5 supply chain managers in the food and beverage distribution industry in the state of Georgia who implemented successful reverse logistics strategies to control cost through risk mitigation. Data were …

Difference In Physical Traits Of Rocky Mountain Tailed Frogs In Burned And Unburned Streams, Daniel M. Franz

Undergraduate Theses, Professional Papers, and Capstone Artifacts

No abstract provided.

Butterflies As Charismatic Indicators : Can Study Of Impact Of On-Farm Habitat Enrichment On Butterfly Populations Provide Insight About Habitat Quality For Other Insects?, Erin Allen

Legacy Theses & Dissertations (2009 - 2024)

Populations of insect pollinators have been declining precipitously across the Northern Hemisphere, due to disease, insecticide application, and habitat degradation and loss. As a result, crop pollination services are at risk, and the ecological insurance provided by biodiversity is in jeopardy. Regional efforts to combat the decline of pollinator diversity and abundance include the New York State Pollinator Protection Plan to assess regional pollinator health, strategies to enhance wild pollinator habitat, as well as on-farm habitat enhancement strategies to augment pollinator populations in and around crops. One such habitat enhancement strategy involves improving native floral resource availability, which is often …

Legislation To Reduce Microplastic Pollution : Understanding The Factors That Facilitated Passage Of The Federal Microbead-Free Waters Act Of 2015, Alyson Kelly Northrup

Legacy Theses & Dissertations (2009 - 2024)

The full environmental impacts of microplastic pollution in aquatic environments remain uncertain, but several detrimental effects have been documented, including adverse health effects in multiple species and the susceptibility of microplastics to adsorb toxins and leach plastic additives. Plastic microbeads from rinse-off personal care products are a source of microplastic pollution that is introduced directly into the environment through runoff, including wastewater treatment plant effluent. In December 2015, the federal Microbead-free Waters Act of 2015 banned the manufacture and sale of all rinse-off personal care products containing plastic microbeads in the United States.

Tribute From The Underworld : The Historical Ecology Of The Maya Postclassic Fish Trade With Isotopic Analysis Of Otoliths From MayapáN And Caye Coco, Jeffrey Michael Bryant

Legacy Theses & Dissertations (2009 - 2024)

This dissertation investigates the Maya fish trade through the extensive analysis of fish otoliths (ear stones), from the Postclassic sites of Mayapán, and Caye Coco, and provides an initial foundation for the development of a historical ecology program. Through osteometry, thin-section microscopy of growth rings, and microscale stable isotope analysis (δC13 and δO18), a spectrum of data is produced to characterize the Postclassic fish trade. These data are used to illuminate themes of the seasonality of the fish harvest, diet, biodiversity, fish population demography, environmental change, sustainability, and resilience. The timing of a seasonal intensification of the harvest is viewed …

Assessing The Spatial And Temporal Variability Of The Detroit River And Harmful Algal Blooms In Western Lake Erie, Angela W. Yu

Dissertations, Master's Theses and Master's Reports

Despite efforts to reduce the occurrence of harmful algal blooms (HABs) in western Lake Erie, blooms recur annually due to agricultural runoff, storms with high winds and heavy rains, and weak lake circulation patterns. The influence from river inputs on the spatial and temporal characteristics of HABs remains relatively unknown. The Detroit River, which contributes about 80% of the basin's total inflow can have a large influence on the spatial and temporal distribution of the bloom. To understand this, optically classified imagery, in situ water measurements, and meteorological and river discharge observations were compiled and synthesized to examine the spatiotemporal …

Gateways-Nd: Building The Institutional Infrastructure Towards Viable Postsecondary Stem Education Reform, J.M.D. Motschenbacher, M. Vosen Callens, J. Nyachwaya, E. Berg, J. Ladbury, R. Reichenbach, P. Kelter

School of Natural Resources: Documents and Reviews

No abstract provided.

Age-0 Walleye Sander Vitreus Display Length-Dependent Diet Shift To Piscivory, Christopher S. Uphoff, Casey W. Schoenebeck, Keith D. Koupal, Kevin L. Pope, W. Wyatt Hoback

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The ontogenetic diet shift to piscivory can be energetically beneficial for fish growth and allows larger, more energetically profitable prey to be consumed. A shift to piscivory may be easier for longer individuals within a cohort due to larger gape size, and an early shift is likely advantageous, potentially leading to increased growth rates and survival. Such length-dependent ontogenetic diet shifts may explain the intracohort variability in length that is common for age-0 walleye (Sander vitreus). The objectives of this study were to describe seasonal intracohort variability in length, identify the timing of the shift to piscivory and …

Ecosystem Size Predicts Social-Ecological Dynamics, Mark A. Kaemingk, Christopher J. Chizinski, Craig R. Allen, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recreational fisheries are complex adaptive systems that are inherently difficult to manage because of heterogeneous user groups (consumptive vs. nonconsumptive) that use patchily distributed resources on the landscape (lakes, rivers, coastlines). There is a need to identify which system components can effectively predict and be used to manage nonlinear and cross-scale dynamics within these systems. We examine how ecosystem size or water body size can be used to explain complicated and elusive angler-resource dynamics in recreational fisheries. Water body size determined angler behavior among 48 Nebraska, U.S.A. water bodies during an 11- year study. Angler behavior was often unique and …

Coastal Wetlands: A Synthesis, Charles S. Hopkinson, Eric Wolanski, Mark M. Brinson, Donald R. Cahoon, Gerardo M.E. Perillo

United States Geological Survey: Staff Publications

What are coastal wetland ecosystems, what are their limits of distribution, and where do they exist in the overall coastal landscape? There are several general definitions for wetlands, but the Ramsar definition is likely the most broadly encompassing (http://www.ramsar. org/), whereas others are more focused definitions tailored to country-specific protection and management policies (Mitsch and Gosselink, 2006). We offer a very general approach rather than a precise definition: coastal wetlands are ecosystems that are found within an elevation gradient that ranges between subtidal depths where light penetrates to support photosynthesis of benthic plants to the landward edge where the sea …

Effects Of Grazing And Fire On Soil Microbial Communities And Hydrological Processes In The Northern Great Plains Grassland, Jacob Comer

Electronic Theses and Dissertations

Historic grazing and fire regimes have been altered with the development of the livestock industry in the Northern Great Plains and have resulted in a reduction of diversity across all scales. As alternative land surface disturbances are developed to combat the loss of diversity, their potential to serve as a sustainable land surface disturbance should be evaluated. To determine the ability of an alternative grazing strategy to serve as a sustainable land surface disturbance, the reaction of the soil microbial community and soil hydrological processes should be evaluated. Objectives of this study were to: 1) evaluate the impact of alternative …

The Tortoise (Wildfire) And The Hare (Heavy Winter Grazing) For Promoting Heterogeneity And Improving Ecosystem Services, Lucas W. Zilverberg

Electronic Theses and Dissertations

The Northern Great Plains (NGP) mixed-grass prairie developed under fire, grazing, and periodic droughts, which created a heterogeneous landscape. Since European settlement, heterogeneous landscapes have declined due to fire suppression and the maximization of livestock production, leading to the need for an alternative management practice. Our overall project objective was to determine if heavy winter grazing could be used as an alternative to patch-burn grazing for promoting heterogeneity and improving ecosystem services in the NGP. Fire has been used very effectively in patch-burn grazing management to create heterogeneity in pastures in some areas, however burning is not readily adopted in …

The Effect Of Edge-Of-Field Nutrient Management Practices On Microbial Concentrations In Subsurface Drainage Water And The Associated Risk Of Antibiotic Resistance Dissemination, Sara Mardani

Electronic Theses and Dissertations

Many in-field and edge-of-field management practices have been used to reduce nutrient loads from agricultural fields. The denitrification woodchip bioreactor (WB) is one edgeof- field management practice that has proven to be effective in removing nitrate from subsurface drainage water. The success in nitrate removal achieved with WBs has raised interest in expanding their capabilities for removing other agricultural pollutants, including phosphorus, by using other types of media like phosphorus-sorbing filters or combining these filters with woodchips to remove both nitrate and phosphorus as dual-nutrient removal systems. Despite the extensive research done on WBs and nutrient filter materials, little consideration …

Characterization Of Chromosomal Translocations In A Group Of Killifish Species By Using Genome-Wide High-Density Snp Mapping Approach, Naznin Sultana Remex

Masters Theses

"The role of chromosomal rearrangements in reproductive isolation and introgression between species is poorly understood. In heterozygous form, rearrangements may directly interrupt meiotic progression leading to partial sterility/subfertility (underdominance) or may suppress local meiotic segregation (recombination suppression). Such unbalanced meiotic segregation may also result in reproductive isolation and play roles as a driving force of speciation. The objective of this study was to gain insight into the pattern of chromosomal rearrangements in two closely related killifish species in the genus Fundulus (F. notatus, and F. olivaceus) by constructing genetic linkage maps using high-resolution single nucleotide polymorphism (SNP) …

Evaluation Of Ufp Number Concentrations Near A Natural Gas Transmissions Station, John M. Thornsbury

Graduate Theses, Dissertations, and Problem Reports (ETD)

Identifying UFP number concentrations near a natural gas compressor station is key to understanding ambient exposures associated with the transmission station. Developing an atmospheric survey to characterize these concentrations was key in understanding ambient exposures. The aims of this study are to compare and contrast number concentrations taken in a hollow, near the transmission station to those of the background. From this, it would be possible to identify whether or not the compressor station was a contributing factor to peaks and spikes in number concentrations.

This study begins with a review of what UFPs are, how they react in different …

Stream Salamander And Benthic Macroinvertebrate Community Responses To Imidacloprid Exposure, Sara M. Crayton

Graduate Theses, Dissertations, and Problem Reports (ETD)

The insecticide imidacloprid is widely used to mitigate hemlock (Tsuga spp.) mortality resulting from the invasive hemlock woolly adelgid (HWA), but evidence suggests that

imidacloprid can have negative effects on adjacent stream systems. Imidacloprid exposure causes physiological changes, bioaccumulation, and reduced survival in anurans, and induces physiological impairment and reduced survival in benthic macroinvertebrates. In this thesis, we assessed whether HWA treatments using imidacloprid affect stream salamander abundances and benthic macroinvertebrate community composition. We also investigated whether imidacloprid or its metabolites bioaccumulate in benthic macroinvertebrates or salamanders and cause sublethal effects. We conducted this study in two National Park …

Soil Health Assessment In Reclaimed Mine Soils, Katie Danielle Stutler

Graduate Theses, Dissertations, and Problem Reports (ETD)

West Virginia is one of the top coal-producing states in the nation, which has resulted in over 500,000 acres of highly disturbed, anthropogenic mine soils caused by surface mining. Mine soils are often rocky and contain low organic matter content, low plant-available nutrients, and toxic metals, which could result in poor soil health and low productivity. Soil health has been defined as the continued capacity of soil to function as a living ecosystem that sustains plants, animals, and humans. It is assumed that with time since reclamation, mine soil properties and related functions may change, and soil health will improve …

Isotopic Composition Of Groundwater And Precipitation In Nebraska, Usa, Mikaela L. Cherry, Troy E. Gilmore, Aaron R. Mittelstet, Didier Gastmans, John Gates

School of Natural Resources: Faculty Publications

Groundwater is vital worldwide for water supply, agriculture and industry. Nearly 60% of all water use in Nebraska is from groundwater. Over 90% of groundwater is used for irrigation in Nebraska, which has the largest area of irrigated land in the United States. Many Nebraskans depend on groundwater for drinking water, both from private wells and municipal wells. The sustainability of groundwater resources is dependent on groundwater recharge. The recharge processes, as well as climatic patterns, influence the stable isotope signatures.

Based on weekly samples collected at two monitoring stations managed by the National Atmospheric Deposition Program (NADP), Harvey (2001) …

Variation In Reproductive Timing For The Northern Long-Eared Myotis (Myotis Septentrionalis) Across Nebraska, Keith Geluso, Cliff Lemen, Patricia Freeman, Brett R. Andersen, Jeremy A. White, Heather M. Johnson

School of Natural Resources: Faculty Publications

The northern long-eared myotis (Myotis septentrionalis), a federally threatened species, occurs in extreme northern, eastern, and southern Nebraska. These regions vary in climate due to geographic location, topography, and elevation. During a 1-week period in early July 2015, we surveyed bats across the state and observed striking variation in the reproductive status for M. septentrionalis. We examined whether or not growing degree days, an abiotic climatic factor used mainly for agricultural practices, was associated with this reproductive variation in a mammalian species. In early July, we captured only pregnant females in the Pine Ridge region of northwestern Nebraska, …

Effects Of Fragmentation On Species Retention In National Parks, Liz Tanner

Master's Theses or Doctor of Nursing Practice

The North American landscape is becoming increasingly fragmented, resulting in habitat patches with decreased area and increased isolation. Often, these patches exist as protected areas, such as national parks. The Theory of Island Biogeography is frequently used as a model for these patches, where each park serves as an ‘island’ surrounded by a ‘sea’ of human-altered habitats. As such, species richness and extinctions in a park might be explained by its area. For this study, I used regression models to examine the relationship between richness and area, as well as extinctions and area, for mammals and birds in national parks. …

The Effects Of Hypoxia And Freshwater Intrusion On The Eastern Oyster (Crassostrea Virginica), James Henry Gledhill

Electronic Theses and Dissertations

Recent estimates revealed a significant decrease in oyster populations worldwide. This drastic decrease has detrimental effects on coastal and estuarine ecosystems. Two environmental stressors that are thought to be contributing to the oyster population decline are hypoxia and excess freshwater intrusion. In this study, effects of hypoxia and low salinity on oysters were investigated using a combination of laboratory and field-based methods. In the laboratory, oysters were exposed to 2, 4, or 8 days of hypoxia (< 2 mg/L dissolved oxygen) folloby 6 days of recovery in normoxic conditions. At the same time, caged oysters were exposed to a naturally occurring hypoxic event in the field. After 8 days, laboratory-exposed oysters shoevidence of immunosuppression indicated by significant downregulation of the immune-related gene thymosin-β4 (Tβ-4) and a significant decrease in total circulating hemocytes compared to controls. However, in field oysters exposed to a naturally occurring hypoxic event, no effect on total hemocyte counts and an upregulation of Tβ-4 was observed. In a second field study, to investigate how oysters respond to prolonged freshwater exposure, caged oysters were placed on 23 April 2019 at six reef sites in the Mississippi Sound along with in situ water quality sensors. One-hundred percent mortality of caged oysters occurred at four of the six sites. Of the 6 six sites, Henderson Point Reef and Kittiwake Reef shosome caged oyster survival. At Henderson Point, where higher mortality was observed compared to Kittiwake, a significant increase in lipid peroxidation was detected. Analysis of mRNA expression of surviving caged and native oysters revealed downregulation of genes involved in immune function, low oxygen response, and osmoregulation. These results show possible evidence of energetic depression which inhibits adequate adaptation to low salinity conditions. Energetic depression and increased oxidative damage could have contributed to higher oyster mortality. Dredge sampling of native oysters at the all Mississippi Sound field sites on 27 September 2019, following recovery to ~15 ppt salinity, still indicated 100% native oyster mortality due to the prior prolonged freshwater exposure. Continued monitoring of western Mississippi Sound oyster reefs is crucial to observe recovery of oyster populations.

Application And Refinement Of Molecular Ecology Techniques For Amphibian Conservation, Stephanie Marie Burgess

Electronic Theses and Dissertations

Wildlife conservation has become increasingly difficult due to habitat loss habitat fragmentation and land use change. Thus conservationists have embraced advances in molecular ecology such as landscape genetics and microbial bioinformatics that employ genetic techniques to further understand the relationship between individuals and their environment. In landscape genetics model inferences can be used to identify features that facilitate or resist gene flow providing a framework for anticipating the impacts of land use changes on a species’ ability to disperse. However the factors that affect the transferability of landscape genetics inferences are poorly understood and little is known about the effect …

Community-Based Coastal Restoration: Long Term Impacts On Habitats And People In Volusia County, Rachel Wimmer

Electronic Theses and Dissertations

Coastal habitats provide invaluable economic and ecosystem services. However, coastlines are eroding at increasing rates due to anthropogenic and climate driven changes. Grey and green infrastructure solutions have been proposed to retard the decay of coastlines, with oysters serving as a popular living shoreline. Three community-based stabilizations that implemented living shorelines and engaged local communities in restoration efforts over the past decade in Volusia County were revisited to determine if they were successful and if they produced positive public perceptions of success. Chicken Island, which was restored after waves, boat wakes, tides, and adverse weather altered the natural shoreline, had …

Island Invasion: The Silent Crisis In Hawaii, Sophia Janssen

Pomona Senior Theses

Keeping out invasive species may, upon first review, seem like a trivial environmental cry from ecologists and deep environmentalists; a belated wish to return to an undeveloped world where nature was pristine. However invasive species create problems that impact all of us and can have far more severe consequences than changing a stunning landscape. These problems are heightened in islands like Hawaii, where the fragile ecosystems have developed over centuries of evolution and adaptation. The introduction of a disease-carrying mosquito can put the people of Hawaii at risk to many vector-born illnesses and create an epidemic, taking human life. The …

Does Helping-At-The-Nest Help? The Case Of The Acorn Woodpecker, Walter D. Koenig, Eric L. Walters, Sahas Barve

Biological Sciences Faculty Publications

Cooperative breeding groups often involve "helpers-at-the-nest"; indeed, such behavior typically defines this intriguing breeding system. In few cases, however, has it been demonstrated that feeding nestlings by helpers, rather than some other behavior associated with helpers' presence, leads to greater reproductive success. One prediction of the hypothesis that feeding behavior per se is responsible for the fitness benefits conferred by helpers is that there should be close congruence between the patterns of helping-at-the-nest and the fitness effects of helpers. Here we look for such a relationship in the cooperatively breeding acorn woodpecker (Melanerpes formicivorus) in order to begin …

Urban Forests In A Changing Environment: Motivations For Tree Planting And Perspectives Of Climate Change Impacts On Urban Forests, Tobias Burnham

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

Urban trees perform several ecosystem services important to humans. Climate variability and poor management threatens urban forests with ecological and socio-economic consequences. Therefore, it is critical urban trees are sustainably managed. For an urban tree management plan to succeed, social inputs at the residential scale must be taken into consideration. The aim of this research is to help inform urban forest managers of social variables that may play an integral role in successful implementation of urban forest management plans. Social factors behind home-owner decision-making to plant or remove trees in the Lincoln and Omaha metro areas show that 75% of …

Evaluating Soil Loss From Ephemeral Gullies With Photogrammetry, Chinthaka B. Weerasekara

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

No abstract provided.