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High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman

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Atmospheric carbon dioxide (CO₂) concentrations have been increasing at an accelerating rate for the past two centuries, profoundly impacting global climate change. Atmospheric CO₂ concentrations are influenced by the global carbon cycle through physical and biogeochemical pathways. Tidal wetland environments play a vital role in the global carbon cycle by offsetting atmospheric CO₂ concentrations through their natural physiochemical processes of high autotrophic productivity, allochthonous organic matter deposition, anoxic soils, and continuous accretion which promotes carbon sequestration with long-term storage at the land-ocean margin. The Intergovernmental Panel on Climate Change (IPCC) and United States Global Change Research …

Partitioning And Microdosimetry Of Plutonium-239 And 55-Iron In Environmental Bacteria Grown In Liquid Cultures, Lisa Manglass

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The work presented herein provides quantitative data related to bacteria exposed in situ to two radionuclides relevant to nuclear sensing: plutonium-239 (²³⁹Pu) and iron-55 (⁵⁵Fe). Originally motivated by the fundamental science underlying biosensing, liquid cultures of Pseudomonas putida and Escherichia coli were exposed to radionuclides over the course of 15-day experimental periods with the intent of gaining insight into the response of these bacteria. An essential component of characterizing or utilizing this response in a meaningful way is an understanding of the dose leading to that response. This dissertation narrows the knowledge gap associated with dose-response …

Green On The Map - The Influence Of Conservation Easements On The Naturalness Of Landscapes In The United States, Nakisha Fouch

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Large protected areas have long been the cornerstone of conservation biology, however, in an era branded by the human dominance of ecosystems, regional landscape structure and function are often a consequence of accumulated land-use decisions that may or may not include a nod to conservation planning. With underrepresentation of habitats in publicly protected areas, attention has focused on the function of alternative land conservation mechanisms. Private conservation easements (CEs) have proliferated in the United States, yet assessing landscape-level function is confounded by holder and donor intent, national and regional policy, regional landscape contexts, varying extents, resolution, and temporal scale. Over …

Characterization Of Water Flow And Solute Transport Driven By Preferential Flow In Soil Vadose Zone, Abdullah Al Mamun

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The vadose zone acts as a buffer zone between the ground surface and the aquifers underneath and controls the transmission of infiltrating water and contaminants, for example, pesticides and chemical spills. Therefore, understanding the flow and transport processes that dominate the vadose zone is important. Macropores are ubiquitous and particularly found in abundance in the vadose zone. These macropores facilitate preferential flow, through which water travels rapidly deep into the soil, bypassing most of the porous matrix. Preferential flow and transport have environmental significance as their processes impact hydrology, ecology, agriculture, subsurface contamination, and waste management sectors. Thus, the overall …

Determining The Value Of Ecosystem Services Provided By Green Stormwater Infrastructure In Coastal South Carolina, Joan U. Ureta

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Rapid urbanization changes the natural hydrology of a landscape, making stormwater management a crucial aspect of land development. As the fastest growing ecosystem globally, an innovative way of managing stormwater is needed to address the increase in urban run-off. In coastal South Carolina, stormwater practices have been widely adopted at the neighborhood level, yet threat of flooding is becoming more evident as the urban population and development continue to rise.

To determine the importance of stormwater practices to coastal residents, we assessed perception on stormwater practices and programs at different decision levels— 1) household, 2) neighborhood, and 3) city/county. Results …

Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker

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Uranium (U) released from the M-Area at the Department of Energy Savannah River Site into Tims Branch, a seasonal wetland and braided stream system, is estimated to be 43,500 kg between 1965 and 1984. The motivation for this work is the uranium’s persistence in the wetland for decades, where it is estimated that 80% of the U currently remains in the Tims Branch wetland. U has begun to incorporate into wetland iron (Fe) and carbon cycles, associating with local Fe mineralogy and deposits of rich wetland organic matter (OM). The objective of this work is to characterize the chemical phases …

Upland Cotton (Gossypium Hirsitum) Root Responses To Reniform Nematode (Rotylenchulus Reniformis) Infection, Wei Li

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Reniform nematode (Rotylenchulus reniformis) is a semi-endoparasitic nematode that causes yield losses in numerous crops, including upland cotton (Gossypium hirsutum). Resistant cotton varieties are urgently needed, but the molecular basis of nematode-host plant interactions is poorly understood. To document plant responses to reniform nematode infection in upland cotton roots, we set up a split-root growth system to collect tissues from infected and uninfected portions of the same root system. A 12-day time course of histology and gene expression of infected roots were generated in Chapter 1. Results suggest reniform nematode infection induced protein synthesis and transport, …

Multi-Factor Models To Resolve Growth Responses In Vitro And During Subsequent Greenhouse Growth For Turmeric (Curcuma Longa L.), Rabia El-Hawaz

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Plant media has been developed over the last six decades, yet, there has not been medium optimized for microplant greenhouse growth, which may be important for producing chemical compounds and preparing transplants for success in the field. A series of multi-factor optimization experiments were conducted on turmeric (Curcuma longa L., genotype L 35-1) to identify the effects of mineral nutrition and plant density in vitro on laboratory and greenhouse production. The first experiment optimized PO43-, Ca2+, Mg2+, and KNO3 for five-months growth in bioreactors with periodic supplementation of sucrose solution +/- nutrients. Phosphorus (6.25 mM) increased sucrose supplement and rhizome …

Decision Environments To Encourage More Sustainable Infrastructure Outcomes, Earl Shealy

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Physical infrastructure (i.e. roads, pipelines, airports, dams, landfills, and water treatment systems) contributes directly to sustainability outcomes such as energy and water use and climate changing emissions. The infrastructure built today will likely impact future generations for many years. Planning, design and development decisions about infrastructure are critical to the future performance of these systems. Such decisions about infrastructure are complex with multiple variables, alternative options, and design stages. To manage decisions that exceed cognitive capacity to consider all options, decision makers often create mental shortcuts (heuristics), and accompanied errors (biases). The potential cognitive biases when dealing with complex decisions …

The Contribution Of Indigenous Ecological Knowledge In Conservation Of Enguserosambu Community Forest, Tanzania, Agnes Sirima

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Community managed forests constitute a significant proportion of the world's forests, however, little is known regarding their condition or the details of how they are managed. Documented benefits of community managed forest include poverty alleviation and in some places a decrease in the rate of deforestation. Although some community based forests do not satisfy the IUCN definition of a protected areas, they provide valuable long term sustainability of forest products and many are also rich in biodiversity and support landscape conservation strategies. Forests are also home to many cultures including the indigenous people. Indigenous communities surrounding forest areas and other …

Values Assigned To National Parks By Hispanics In The United States: Castillo De San Marcos And Fort Matanzas Nm And Great Smoky Mountains Np, Carla Mora-Trejos

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The integrity of Parks and Protected Areas (PPA) depends on management that acknowledges their position as part of the socio-cultural context and demonstrates awareness and attention to ethnic and racial dimensions of the communities adjacent to these areas. The Unites States National Park Service has dedicated resources and effort to determine ways to keep units in the national park service relevant in a changing world. The fastest growing and second largest demographic in the Unites States is the Latino or Hispanic population. Very little has been published about this rapidly growing population of Latin Americans residing in the United States …

Earth Abundant Thin Film Technology For Next Generation Photovoltaic Modules, Githin Alapatt

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With a cumulative generation capacity of over 100 GW, Photovoltaics (PV) technology is uniquely poised to become increasingly popular in the coming decades. Although, several breakthroughs have propelled PV technology, it accounts for only less than 1% of the energy produced worldwide. This aspect of the PV technology is primarily due to the somewhat high cost per watt, which is dependent on the efficiency of the PV cells as well as the cost of manufacturing and installing them. Currently, the efficiency of the PV conversion process is limited to about 25% for commercial terrestrial cells; improving this efficiency can increase …

Empowering Citizens In A Global Era: A Grounded Theory Study Of Community Gardens, Anita Tam

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In our global era, the modern food system can be viewed as consisting of a dominant macro-level corporate food industry, challenged by broad-based meso-level food justice and democracy movements, which are in turn fueled by micro-level community food initiatives. Research has yet to examine the role of community gardens in the context of this complex, multi-level food system. Grounded theory methodology was thus used to explore the deeper meaning of the community gardening experience to participants, in order to better understand the ways in which community gardens may scale up and contribute to democratizing the food system. Analysis of the …

The Challenges And Opportunities Throughout The Life Cycle Of Landscape-Scale Collaborative Conservation Organizations: Case Studies In The Southern Appalachians And The Northern Rockies Ecosystems, Jennifer Thomsen

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Currently our natural environment is threatened by climate change, habitat fragmentation, and other transboundary issues. To address these problems, it is thought that conservation organizations and land management agencies should attempt to manage at larger geographic scales and across political boundaries. The Crown Managers Partnership (CMP) and the Southern Appalachian Man and the Biosphere Cooperative (SAMAB) are two such organizations that work at an ecoregional scale to support collaboration among agencies, aboriginal groups, conservationists, scientists, and other stakeholders for the conservation and restoration of the Northern Rocky Mountain and the Southern Appalachian regions in North America. Over the past decades, …

A Comprehensive Assessment Methodology Based On Life Cycle Analysis For On-Board Photovoltaic Solar Modules In Vehicles, Mahmoud Abdelhamid

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This dissertation presents a novel comprehensive assessment methodology for using on-board photovoltaic (PV) solar technologies in vehicle applications. A well-to-wheels life cycle analysis based on a unique energy, greenhouse gas (GHG) emission, and economic perspective is carried out in the context of meeting corporate average fuel economy (CAFE) standards through 2025 along with providing an alternative energy path for the purpose of sustainable transportation. The study includes 14 different vehicles, 3 different travel patterns, in 12 U.S. states and 16 nations using 19 different cost analysis scenarios for determining the challenges and benefits of using on-board photovoltaic (PV) solar technologies …

Applied Statistics In Environmental Monitoring: Case Studies And Analysis For The Michigan Bald Eagle Biosentinel Program, Katherine Leith

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The bald eagle (Haliaeetus leucocephalus) is an extensively researched tertiary predator. Its life history and the impact of various stressors on its reproductive outcomes have been documented in many studies, and over many years. Furthermore, the bald eagle population recovery in Michigan has been closely monitored since the 1960s, as it has continued to recover from a contaminant-induced bottleneck. Because of its position at the top of the aquatic food web and the large body of ethological knowledge, the bald eagle has become a sentinel species for the Michigan aquatic ecosystem. In April 1999, the Michigan Department of Environmental Qualtity, …

An Experimental Investigation Towards Improvement Of Thermoelectric Properties Of Strontium Titanate Ceramics, Arash Mehdizadeh Dehkordi

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The direct energy conversion between heat and electricity based on thermoelectric effects is a topic of long-standing interest in condensed matter materials science. Experimental and theoretical investigations in order to understand the mechanisms involved and to improve the materials properties and conversion efficiency have been ongoing for more than half a century. While significant achievements have been accomplished in improving the properties of conventional heavy element based materials (such as Bi$_2$Te$_3$ and PbTe) as well as the discovery of new materials systems for the close-to-room temperature and intermediate temperatures, high-temperature applications of thermoelectrics is still limited to one materials system, …

South Atlantic Stream Fish Assemblages: Multi-Scale Structuring Factors, Trait Associations And Channelization, And Responses To Dam Removal, Cathy Marion

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South Atlantic coastal plain wadeable streams are unique and understudied freshwater environments that provide crucial habitats for a wide range of aquatic taxa. In Chapter 1, we investigated patterns in fish assemblages across South Carolina's coastal plain, and developed statistical models to identify the dominant multi-scale abiotic environmental factors that influence assemblage structure. Our analyses indicated the presence of four predominant fish assemblages that commonly occur in the coastal plain, which we termed the: 1) fluvial, 2) eastern mudminnow, 3) centrarchid, and 4) non-fluvial assemblages. Natural geographic gradients and instream habitat parameters associated with velocity, channel form, stream size, and …

Investigation Of Concurrent Energy Harvesting From Ambient Vibrations And Wind, Amin Bibo

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In recent years, many new concepts for micro-power generation have been introduced to harness wasted energy from the environment and maintain low-power electronics including wireless sensors, data transmitters, controllers, and medical implants. Generally, such systems aim to provide a cheap and compact alternative energy source for applications where battery charging or replacement is expensive, time consuming, and/or cumbersome. Within the vast field of micro-power generation, utilizing the piezoelectric effect to generate an electric potential in response to mechanical stimuli has recently flourished as a major thrust area. Based on the nature of the ambient excitation, piezoelectric energy harvesters are divided …

Understanding Public Perceptions About Beach Nesting Shorebirds And Habitat Management On Cape Cod, Massachusetts, Marla Hamilton

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Coastline habitats along the eastern seaboard of North America serve as prime locations for beachfront development and consumptive and non-consumptive recreational opportunities. Many of these areas are also globally important nesting and wintering areas for threatened and endangered shorebirds (primarily species belonging to the order Charadriiformes). Across the span of their hemispheric ranges, shorebirds face significant threats due to increases habitat loss, human disturbance, and illegal hunting practices. With coastline use increasing human-wildlife interactions, positive public input and interaction is needed to mitigate negative consequences to wildlife. Although many techniques have been employed to discourage beach users from practicing recreational …

Isolated And Ephemeral Wetlands Of Southern Appalachia: Biotic Communities And Environmental Drivers Across Multiple Temporal And Spatial Scales, Joanna Hawley

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Throughout the world, wetlands are known to support a wide variety of taxa as well as high levels of biodiversity and species richness. Although the ecological significance of wetlands is well documented in the scientific literature, efforts to map and assess wetlands on regional or national scales (e.g., National Wetlands Inventory (NWI)) often overlook wetlands which are either very small (< 1 ha) or have ephemeral hydroperiods. While the vast majority of wetland research in the southeastern United States has focused on wetlands distributed across the coastal plain ecoregion, very little information exists on small and/or ephemeral wetlands in areas of southern Appalachia, although there are several notable exceptions. Despite the paucity of small wetland data in this region, the southeastern US is known as a hotspot for both aquatic biodiversity and species endemism. My goal with this project was to examine the biotic communities inhabiting small, ephemeral and geographically-isolated wetlands to identify the major environmental drivers that contribute to observed community patterns and species' distributions. I studied a set of small, mostly-ephemeral, mostly-isolated wetlands (N = 41) in the upper Piedmont and lower Blue Ridge ecoregions of South Carolina from January-June of 2010 and 2011 and focused my efforts on describing the structure, biotic communities and surrounding habitat characteristics of my study wetlands. I observed high levels of species richness and biodiversity in this previously-undocumented wetland system, despite the small size and ephemeral nature of study wetlands. My results indicated that the amphibian and benthic invertebrate communities of small, ephemeral wetlands responded to different environmental drivers (e.g., wetland depth, area, hydroperiod, canopy cover, surrounding land use types) occurring across multiple spatial and temporal scales. Additionally, the amphibian community was significantly influenced by a number of environmental variables occurring at both the within-pond scale and larger spatial scales (250 m, 500 m and 1 km surrounding land cover variables). By contrast, the benthic invertebrate community was significantly influenced primarily by variables occurring at the within-pond scale. This wetland system also served as both breeding and overwintering habitat for a variety of species such as wood frogs (Lithobates sylvatica), spotted salamanders (Ambystoma maculatum), bullfrogs (Lithobates catesbeiana), cricket frogs (Acris crepitans). This study highlights the ecological importance of small, ephemeral aquatic habitats in a region where little research exists regarding such systems; these often-unnoticed ecosystems are likely the result of a combination of historical anthropogenic and natural environmental process. These legacy wetlands (i.e., wetlands that are the unintended result of some human-induced environmental change in either the recent or long-term past) are found ubiquitously across the landscape and are often missed by coarse-filter mapping approaches (e.g., National Wetlands Inventory). I observed many study wetlands to be extremely small in size (< 0.05 ha) and that many wetlands were habitats of circumstance and opportunity rather than of permanence and predictability. The ephemerality of the majority of study wetlands demonstrates the biological significance of small, temporary habitats for many species requiring these habitats for breeding activity. Despite the small size and ephemeral nature of my study wetlands, I found that these wetlands represented a large proportion of amphibian biodiversity in the regional species pool and thus, are an important conservation feature at the local, landscape and regional scales. My study demonstrates that small, semi-isolated, mostly-ephemeral wetlands in southern Appalachia support high levels of biodiversity and are an important asset deserving of further study and conservation recognition.

Arachidonic Acid Reverses The Pyriproxyfen And Ibuprofen Induced Toxicity In Daphnia Magna, Gautam Kumar Ginjupalli

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Healthy reproduction and neonatal sex ratios of Daphnia are crucial to the health of the aquatic ecosystems in which Daphnia play principal roles in trophic transfer of nutrients. Combinations of environmental factors such as availability and quality of diet, overcrowding, hypoxia, reduced photoperiods and fall in ambient temperatures perturb normal parthenogeneic reproduction and induce sexual reproduction through male production. Male production provides a mechanism for overcoming specific stressors such as overcrowding and overwinter pond desiccation. However, it also induces a decrease in the Daphnia population that could have adverse implications on the pond ecosystem that depend on Daphnia . Interestingly, …

Ecology And Impacts Of Coyotes (Canis Latrans) In The Southeastern United States, Cady Etheredge

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Recent coyote (Canis latrans ) colonization of the southeastern United States has prompted speculation on the top-down effects of a new top predator on systems which have gone without a strong predator presence since the extirpation of the red wolf (Canis rufus ). This dissertation reports on the results of a series of investigations of the potential impact of coyotes on raccoons (Procyon lotor ) and other management issues related to coyotes in the Southeast. Chapters 1-3 present indirect field tests of the Mesopredator Release Hypothesis. Chapter 4 presents an overview of the current knowledge of the …

Factors Affecting The Surface-Mediated Reduction Of Plutonium In The Presence Of Pure Mineral Phases, Amy Hixon

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The overall objective of the research is to investigate the mechanistic and kinetic aspects of the surface-mediated reduction of plutonium. The first chapter is a critical review of plutonium sorption to pure mineral phases. The objective is to study if and how the mechanisms by which plutonium interacts with mineral surfaces are connected to mechanisms for the surface-mediated reduction of plutonium. The main conclusion of the review is that advanced spectroscopy, microscopy, and molecular modeling are needed to fully understand not only the surface structure of pure mineral phases, but also the coordination and bonding environment of plutonium surface complexes. …

An Investigation Into The Interactions Of Gold Nanoparticles With Aquatic Vascular Macrophytes, James Glenn

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Nanomaterials (NMs) have promised lighter, stronger, smaller and more efficient products in areas such as electronics, medicines and even environmental sectors. This investigation started at the base of the food chain and characterized NMs interactions with aquatic plants. Citrate capped gold nanoparticles were used as a model nanoparticle to track fate and gain insight on factors that influence gold nanoparticle (AuNP) bioavailability and absorption. Four species of aquatic macrophytes were investigated. Azolla caroliniana, Myriophyllum simulans, Egeria densa and Myriophyllum aquaticum were selected due to growth habitat, leaf morphology and root structure. Because aquatic plants absorb the majority of their nutrients …

Long-Term Bald Eagle Monitoring: Assessing Emerging Risks To The Great Lakes Ecosystem By Evaluating Impacts To Tertiary Predators, Latice Fuentes

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Data from the Michigan Bald Eagle Biomonitoring Project (MBEBP) was used to provide ecological evaluations amidst concerns of emerging contaminants and environmental change. Samples and measurements were collected throughout the state of Michigan from 1998-2012. Nestling breast feathers and biometric measurements were used in analytical and statistical analyses which provided a broad assessment of the Great Lakes ecosystem and its resident bald eagles. Bald eagle nestling feathers were taken from Michigan breeding areas, and used to evaluate spatial and temporal trends of mercury (Hg). Overall, remediation has positively affected the Great Lakes region. However, Michigan's Upper Peninsula and Lake Superior …

Attaining Sustainable Behavior Among Non-Environmentally-Motivated Individuals: A Formative Experiment, Brooklynn Wynveen

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Experts agree that overconsumption is a major problem in Western culture today, particularly in the United States. Thus, it is important to promote sustainable behavior among the general public. And yet, existing educational programming geared toward promoting such behavior changes remains appealing largely to environmentally-motivated audiences, as opposed to individuals with alternative (i.e., social and economic) motivations. In response to this discrepancy, I conducted a formative experiment with the goals of: 1) fostering participation among non-environmentally-motivated individuals in sustainable living educational programming; and 2) obtaining behavior change commitments, in the direction of more sustainable lifestyles, from those participants.
As part …

Fate And Reactivity Of Natural And Manufactured Nanoparticles In Soil/Water Environments, Allison Vandevoort

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Nanoparticles (NPs), < 100 nm in diameter, make up the smallest component of solid material. This small size often causes increased reactivity in soil/water environments, which is true for both natural NPs, such as very fine clay particles, and for manufactured nanoparticles, such as silver nanoparticles (AgNPs). As the importance of these particles is more widely recognized, and as manufactured nanoparticles, especially AgNPs, are increasing in production, it is essential to consider their effect on terrestrial and aquatic environments. The studies presented in this dissertation show that both the physicochemical characteristics of the NPs (e.g., particle size, surface coating, elemental composition), as well as soil-water interfacial chemistry (e.g., ionic strength, ligand concentration, pH), are instrumental in predicting environmental fate and reactivity.
Ligand type and concentration were especially important in NP reactivity and bioavailability. Using the hard/soft acid/base concept, the effect of phosphate ligand (hard base) on Fe/Al (hard acid) oxyhydroxide natural NPs was investigated in Chapters 2 and 3. Adding phosphate to soil NPs and reference nano-minerals (Fe-(oxyhydr)oxides and kaolinite) caused coagulation or dispersion, changing the particle size of the NPs, as well as affecting the amount of phosphate in its bioavailable (i.e., dissolved) form. A review of the literature in Chapters 1 and 3 revealed that changes in the soil conditions, and therefore, soil colloids/NPs (e.g., increasing organic …

Spider Mediation Of Polychlorinated Biphenyl Transport And Transformation Across Riparian Ecotones, Diana Delach

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Polychlorinated biphenyls (PCBs) contaminate the sediment of the Twelvemile Creek / Lake Hartwell Superfund Site, and are known to be transported throughout the resident biota via trophic transport. Riparian spiders have recently become of interest because they are terrestrial organisms that have significant PCB exposures derived from aquatic sources. Many riparian spiders primarily consume insects emerging from contaminated aquatic systems, and these spiders can have a body burden as high as 2900 ng/g lipid. These emergent insects carry contaminants out of the river and into the riparian zone where they are captured by spiders, which effectively directs the contamination towards …

Conservation Needs Of Nearshore Seabirds In The Southeastern U.S. Addressed Through Habitat Use Surveys And Assessments Of Health And Mercury Concentrations, Lisa Eggert

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Seabirds encounter a range of natural and anthropogenic stressors in the nearshore environment and are ideal candidate species for long-term monitoring of changes to coastal systems. The mitigation of threats to nearshore seabirds requires management of essential coastal habitat and monitoring population health and trends. In this dissertation, I first evaluated intertidal habitat use for a suite of coastal species as it relates to management practices at a seabird nesting island in South Carolina. Specifically, my objectives were (1) to determine intertidal areas of high bird abundance, (2) to examine course-scale habitat characteristics and human use of intertidal areas associated …