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The Role Of Above- And Belowground Interactions For Plant Allocation, Sophia Carmel Turner

Doctoral Dissertations

My dissertation builds upon decades of research on plant resource allocation, by incorporating multispecies interactions, above- and belowground, with the overarching goal of uncovering the role of a whole community in shaping plant resource allocation and change to subsequent interactions. I accomplished this goal by establishing two controlled common garden experiments where I manipulated the biotic community that a focal plant is exposed to. Using these experiments, 1) I tested whether plant neighbors alter a focal plant’s resource allocation through changes to above- or belowground processes, and if these allocation changes resulted in any indirect effects on the focal plant’s …

Physical Activity On Multiuse Trails And In A Novel Bike Park Within An Urban Wilderness, Douglas Gregory

Doctoral Dissertations

Research has shown that the presence of, access to, and use of parks and trails is associated with increased levels of PA. However, little research exists on nature-based, recreational multiuse trails and bike-specific amenities within parks and their impact on PA. Therefore, to explore the effect trails and bike parks have on PA, this dissertation conducted three investigations to: 1) determine the impact of trail/greenway interventions on PA, 2) investigate how seasonality and weather influence nature-based recreational trail use, and 3) develop a demographic and PA profile of bike park users.

Investigation 1 (Chapter 4) systematically reviewed the literature specific …

Metagenomic Profiling Of Cave Biofilms, With A Focus On Chemolithoautotrophy And Pseudonocardiaceae, John A. Fulginiti

Masters Theses

The dark, humid, and nutrient depleted conditions of caves set limitations on habitability and result in microbial diversity and community structures that differ from surface environments. Recent studies investigating cave microbiomes reveal that Pseudonocardiaceae, a family of bacteria belonging to the phylum Actinomycetota, are abundant in cave sediment and on rocks as subaerial biofilms, however little work has been done on attempting to characterize their diversity and metabolism within the environment. This study used shotgun metagenomics to characterize the functional potential of Pseudonocardiaceae, as well as other cave microbes, in cave site KN14 located in Knox County, Tennessee. Functions of …

Computational Analysis Of Microbial Sequence Data Using Statistics And Machine Learning, Zhixiu Lu

Doctoral Dissertations

Since the discovery of the double helix of DNA in 1953, modern molecular biology has opened the door to a better understanding of how genes control chemical processes within cells, including protein synthesis. Although we are still far from claiming a complete understanding, recent advances in sequencing technologies, increased computational capacity, and more sophisticated computational methods have allowed the development of various new applications that provide further insight into DNA sequence data and how the information they encode impacts living organisms and their environment. Sequencing data can now be used to start identifying the relationships between microorganisms, where they live, …

Montezuma Quail In The Edwards Plateau Of Texas: Detection, Occurrence, And Habitat, Zachary J. Pearson, Eric D. Grahmann, Fidel Hernández, Robert Perez, Leonard A. Brennan, Humberto L. Perotto-Baldivieso

National Quail Symposium Proceedings

Montezuma quail (Cyrtonyx montezumae) were historically found throughout nearly every county in the Edwards Plateau region of Texas, USA. Over the last century, shifting land use, reduction of fire on the landscape, and the subsequent encroachment of woody vegetation have constricted the distribution of Montezuma quail to a few counties in the southern portion of the Edwards Plateau. A renewed interest in management for Montezuma quail over the last decade has been met with a lack of information regarding their habitat requirements in this region. This lack of general information and increased sightings of this elusive species in …

Effect Of Food Distribution On Northern Bobwhite Resource Selection, Rachel R. Gardner, John Maerz, Theron M. Terhune Ii, Ira B. Parnell, James A. Martin

National Quail Symposium Proceedings

Supplemental feeding is a common management tactic used to increase survival and reproduction of northern bobwhite (Colinus virginianus; hereafter, bobwhite). Different supplemental feeding methods alter the distribution of resources across a landscape in unique ways and may influence the space use and resource selection of target species differently. Predators may concentrate their movements near fed sites, and different distributions of supplemental feed may encourage bobwhite to concentrate their movements closer to feed than other areas, thereby altering the potential for predator-prey interactions near feed. We used radio-tracked locations and movements in areas with stationary feeders (“feeder fed”) and …

Cerulean Warbler Full Annual Cycle Ecology: Filling In Critical Knowledge Gaps, Douglas W. Raybuck

Doctoral Dissertations

Cerulean Warblers (Setophaga cerulea) are a declining migratory bird species of conservation concern that breed in mature hardwood forests of eastern North America and spend the stationary non-breeding period in the tropical Andes of South America. To reverse their >50-year population decline, a full annual cycle conservation strategy is needed. However, several important knowledge gaps have limited our understanding of this species’ full annual cycle ecology, including migration ecology, response to forest management on the breeding grounds, and basic ecology during the stationary non-breeding period in Andean forests. From geolocator data, we found a moderate pattern of migratory …

Lidar Evaluation Of The Structural Complexity Of Multi-Cropped White Oak (Quercus Alba) And Pine (Pinus Spp.) Plantings In East Tennessee, Usa, Bret Alan Elgersma

Masters Theses

Structural complexity has an important influence on wildlife habitat and several other ecosystem services. Establishment of white oak (Quercus alba) intercropped with loblolly pine (Pinus taeda), shortleaf pine (Pinus echinata), or eastern white pine (Pinus strobus), in 2014 provided the opportunity to investigate effects of planting species mixtures in different spatial arrangements on structural complexity. Terrestrial LiDAR was used to evaluate the structure of each intercropped treatment and monoculture control. The measures of complexity included: 1) rumple 2) top rugosity 3) standard deviation of individual tree crown area, 4) standard deviation of …

The Effects Of Urbanization On The Avian Gut Microbiome, Mae Berlow

Doctoral Dissertations

The gut microbiome influences and is influenced by the host, and can affect the host organism by contributing to health, development and immunity. Similarly, the host can influence this community; it’s makeup can vary with host species, locality, diet, social stressors, and environmental stressors. Some of these environmental stressors have arisen due to human-induced rapid environmental change, like urbanization. The physiology and behaviors of organisms that are able to persist in urban environments are often different from their non-urban congeners. Nutrition, development, and immunity—all of which are affected by the gut microbiome—are important factors that can determine survival in urban …

Evolution And Resurrection Ecology Of A Foundational Coastal Marsh Plant, Jennifer L. Summers

Doctoral Dissertations

Stratified storage of dormant seeds in soil can result in natural archives useful for studying evolutionary responses to environmental change. However, few studies leverage soil-stored seed banks as natural archives, in part because of concerns over attrition, bias, and sediment mixing. Here, I examine the persistent seed bank of Schoenoplectus americanus, a foundational brackish marsh sedge, to a) determine whether it can serve as a resource for reconstructing demographic and population genetic/genomic variation, b) whether and how evolution may be occurring across a century. After extracting seeds from radionuclide-dated soil cores taken across the Chesapeake Bay, I “resurrected” age …

Checklist Of The Inland Fishes Of Louisiana, Michael H. Doosey, Henry L. Bart Jr., Kyle R. Piller

Southeastern Fishes Council Proceedings

Since the publication of Freshwater Fishes of Louisiana (Douglas, 1974) and a revised checklist (Douglas and Jordan, 2002), much has changed regarding knowledge of inland fishes in the state. An updated reference on Louisiana’s inland and coastal fishes is long overdue. Inland waters of Louisiana are home to at least 224 species (165 primarily freshwater, 28 primarily marine, and 31 euryhaline or diadromous) in 45 families. This checklist is based on a compilation of fish collections records in Louisiana from 19 data providers in the Fishnet2 network (www.fishnet2.net). The checklist has grown because of descriptions of three new species, new …

Theoretical And Quantitative Methods Connecting Characterizing Micoribal Metabolism Diversity: Implciations From Phylogenetics, Community Diversity, And Organic Geochemistry, Taylor Royalty

Doctoral Dissertations

Biogeochemistry is controlled by microorganisms obtaining nutrients and energy. Thus, microbial metabolisms directly link microbial ecology and geochemistry. The extent that microbial ecology and geochemistry microbial ecology and geochemistry affects the other requires constraint on the spatiotemporal distribution and abundance of microbial metabolisms with respect to geochemistry, or the microbial niches. Elucidating microbial metabolisms was challenging prior to the advent of ‘omics sequencing technologies, as most microbial lineages lack cultured representatives. Although revolutionizing microbial ecology, challenges still exist in fully leveraging information derived from ‘omics technologies. This dissertation attempts to address a small subset of these challenges that include quantifying …

Connecting The Social And Spatial Behaviors Of A Territorial Species (Anolis Carolinensis), Jordan M. Bush

Doctoral Dissertations

Why animals live where they do is a key question in ecology and evolution. An individual’s home range determines the resources they have access to, conspecifics they encounter, and predators and pitfalls they must avoid. Home range behaviors also have an inherently social component; where animals live affects the rivals they compete with and the mates they have access to. This is especially true in territorial species, as defensive displays make up a large portion of their social behaviors. In this dissertation, I sought to understand how territorial behaviors affect the social lives of the green anole lizard (Anolis …

Aspects Of The Physiological And Behavioral Defense Adaptations Of The Mountain Madtom (Noturus Eleutherus), Meredith Leigh Hayes

Masters Theses

Madtoms (Noturus spp.) are a highly endemic clade of miniature catfishes that faces widespread imperilment. Little is known about the ecology of these secretive fishes, and understanding the behavioral and physiological adaptations madtoms have evolved to resist pathogens and competitors is necessary for conservation.

Madtoms nest under cover and provide extensive paternal care. Attempts to rear eggs in captivity result in high mortality rates from infection, leading to questions about how wild nests resist disease. In many fishes, males produce antimicrobial substances that confer protection to eggs. To determine if guardian males deter disease in nests, Mountain Madtoms ( …

Physiological Ecology Of Four Endemic Alabama Species And The Exotic Asiatic Weatherfish, Misgurnus Anguillicaudatus (Cantor, 1842), Lindsay M. White, Mark E. Meade, Benjamin A. Staton

Southeastern Fishes Council Proceedings

The occurrence of Asiatic Weatherfish, Misgurnus anguillicaudatus, in Alabama, a state known for its rich biodiversity, has generated concern among conservation managers. The current study used respirometry techniques to investigate the effects of increasing temperature on four native southeastern fishes (one cyprinid, two percids, and one elassomid) and the non-native M. anguillicaudatus. A minimum of five individuals of each species were used, and three experimental temperatures were chosen to represent spring and summer averages of northeast Alabama streams (15, 20, and 25°C). Overall, mean standard metabolic rates (SMRs) for M. anguillicaudatus were low (97.01, 127.75, and 158.50 mg …

Assessing The Functional Similarity Of Native And Invasive Anolis Lizards In The Food Webs Of Structurally-Simple Habitats In Florida, Nathan W. Turnbough

Doctoral Dissertations

Invasive species often displace ecologically-similar native species, but the extent to which invading and displaced species function similarly in the food web processes of invaded communities is largely unknown. I investigated whether populations and individuals of an invasive Anolis lizard (the brown anole, Anolis sagrei) and the native congener it displaces in Florida (the green anole, Anolis carolinensis) are functionally equivalent in the food webs of open and structurally-simple habitats. In a system of invaded and uninvaded dredge-spoils islands, I found that both arthropod communities and winter bird communities covaried with brown anole abundance (and therefore the identity …

Intensive, Regular Sampling And Removal Of Modest Numbers Of Fishes Shows No Measurable Impact On Fish Populations In Three Streams Of North Georgia, Steven L. Powers

Southeastern Fishes Council Proceedings

Recent publications and restrictions on collecting by state fish and game managers indicate a growing concern regarding the impact of field sampling on native fish populations. To evaluate the validity of these concerns, data from five life-history studies conducted in Cherokee County, Georgia were examined to test the hypothesis that regular sampling has a negative impact on fish populations. Number of individuals collected was divided by time collecting to calculate catch per unit effort (CPUE) as an indicator of relative abundance for each species. The collecting sequence (i.e. the number of times a species had previously been sampled) was regressed …

An Ecological Study Of The Kudzu Bug In East Tennessee: Life History, Seasonality, And Phenology, Kadie Elizabeth Britt

Masters Theses

The kudzu bug, Megacopta cribraria (Hemiptera: Plataspidae), an invasive species from Asia, was first discovered in the United States in 2009 in Georgia. It has since spread to other states, including Tennessee, where it has spread rapidly to numerous counties in four years. Its common name, kudzu bug, implies a potential benefit to management of the invasive species kudzu; unfortunately, the kudzu bug has shown little impact on reducing growth of kudzu. The kudzu bug causes agricultural, urban, and health-related concerns in the United States. Soybean losses by kudzu bug have exceeded 20% in some areas of the southeastern United …

Improving Aedes Mosquito Surveillance And La Crosse Virus Screening In Eastern Tennessee, Cassandra Urquhart

Masters Theses

La Crosse virus (LACV), transmitted by infected Aedes triseriatus, Ae. albopictus, and Ae. japonicus mosquitoes is the leading cause of pediatric arboviral encephalitis. Severe cases of LAC encephalitis occur in individuals 16-years-old or younger and may cause permanent neurological damage or fatality. No vaccines exist making mosquito control and disease prevention crucial to public health. Effective screening and surveillance practices are key components to these goals. While a number of standard mosquito surveillance methods exist, continuous testing and improved understanding of vector biology to determine the best ways to implement these methods is important. Additionally, the current standard …

Characterizing Early-Life Microbiome Functionality In Premature Infant Gut By A Metaproteomics Approach, Weili Xiong

Doctoral Dissertations

Microbes inhabit all parts of human body that are exposed to the environment and their interactions with human host mutually benefit each other and play significant roles in human health and diseases. The human gastrointestinal tract harbors the largest population of the microbiota and has gained broad research attention and efforts over the past decade. Colonization of the gut by microbes begins at birth and this early-life bacterial establishment can impact infants’ health and even the human health and lifestyle across an entire life span. Recent studies on community structure and composition of infant gut microbiota have revealed the species …

Individual Variation In Plant Traits Drives Species Interactions, Ecosystem Functioning, And Responses To Global Change, Quentin Daniel Read

Doctoral Dissertations

Ecologists have long sought to understand the processes that lead to the riotous diversity in communities of organisms that inhabit disparate climates and landscapes. Such a diversity of traits leads to a diversity of interactions among species in natural communities, which in turn generates a diversity of potential responses to ongoing global change. In this dissertation, I do three things: I explore the forces that structure plant communities and the ecosystem functions that they mediate, I describe patterns of variation among communities, species, and individual organisms across environmental contexts, and I disentangle the direct effects of global change from the …

Using Phylogenetics To Understand The Evolutionary Relationships Of Hibiscus Section Furcaria, Whitaker Matthew Hoskins

Masters Theses

Neopolyploids constitute at least 35% of known species of angiosperms, and because polyploidization is a pertinent process in plant diversification and domestication, it is a thriving field of study. Hibiscus section Furcaria includes several groups of polyploids in addition to ten known diploid species. In previous studies genome groups for Hibiscus section Furcaria were determined through artificial hybridization experiments and patterns of biogeography were elucidated based on the distribution of diploids and polyploids. For instance, the Australian hexaploids contain 3 genomes (designated G, J, and V) and are thought to have developed from a polyploidization event between an African diploid …

Diet Of And Prey Availability For Reintroduced Juvenile Lake Sturgeon (Acipenser Fulvescens) In Ft. Loudoun Reservoir, Tennessee, Todd Michael Amacker

Masters Theses

After fifteen years of reintroducing juvenile Lake Sturgeon (Acipenser fulvescens) in the Upper Tennessee River Basin, fisheries biologists are researching basic ecological traits of subsistent organisms. I set out to seasonally assess whether Lake Sturgeon forage opportunistically or selectively in Ft. Loudoun Reservoir. After anesthetizing individual juvenile Lake Sturgeon caught on trotlines in a 13-km reach of the reservoir, I used colonic flush and gastric lavage techniques to describe diets quantitatively. I also used two methods to assess available prey items in the study area by 1) taking systematic benthic grabs along several transects across the width of …

Bacterial Diversity And Function Within An Epigenic Cave System And Implications For Other Limestone Cave Systems, Kathleen Merritt Brannen-Donnelly

Doctoral Dissertations

There are approximately 48,000 known cave systems in the United States of America, with caves formed in carbonate karst terrains being the most common. Epigenic systems develop from the downward flow of meteoric water through carbonate bedrock and the solutional enlargement of interconnected subsurface conduits. Despite carbonate karst aquifers being globally extensive and important drinking water sources, microbial diversity and function are poorly understood compared to other Earth environments. After several decades of research, studies have shown that microorganisms in caves affect water quality, rates of carbonate dissolution and precipitation, and ecosystem nutrition through organic matter cycling. However, limited prior …

A New Adaptive Landscape: Urbanization As A Strong Evolutionary Force, Lauren Christie Breza

Masters Theses

Urbanization is rapidly increasing as human population growth steadily grows, but there is little consensus of the ecological consequence of this population shift and almost no information of the evolutionary consequences for local biodiversity. Nearly two-thirds of the world’s population will live in city centers by 2050 with profound impacts on landscapes that can act as important agents of selection. This study aims to identify 1) the net effect of urbanization on species richness, 2) how phylogenetic diversity varies between urban and rural sites, and 3) the strength of urbanization as a selection pressure. First, a meta-analysis was conducted in …

Phylogenetic Analysis And Revision Of The Nearctic Androprosopa Mik (Diptera: Thaumaleidae) With An Emphasis On The Western Species, Robert John Pivar

Masters Theses

The family Thaumaleidae, also known as seepage midges, is an uncommonly encountered, understudied family of aquatic Diptera compared to its sister group, the Simuliidae. The goal of this project was to assess species diversity of the Nearctic Thaumaleidae and determine relationships among them. The western Nearctic fauna of Androprosopa Mik is revised to include twenty-eight species, six of which are described as new to science. Descriptions of the adult males of A. apache, A. arnaudi, A. magnipelvim, A. rainierensis, A. sierra and A. uvas are provided. Redescriptions of all remaining species are also provided, as well …

Population Dynamics And Ecophysiology Of Fraser Fir (Abies Fraseri) In The High Elevation Forests In The Southern Appalachian Mountains, Steven Douglas Kaylor

Doctoral Dissertations

Dominated by the endemic Fraser fir (Abies fraseri), the high-elevation forests of the Southern Appalachians are one of the most endangered ecosystems in the United States, and the future of these forests remains uncertain. Fraser fir is showing signs of decline in health and increased mortality throughout its range, possibly due to multiple environmental stresses.

Using twenty years of forest monitoring data, this dissertation documents change in forest structure and species composition in high-elevation red spruce-Fraser fir forests in southern Appalachia and generates predictions of future forest change. Additionally, it quantifies physiological measures of carbon fixation, storage and …

Exploring How Clean Water Act Enforcement Influences Stream Macroinvertebrate Communities, Shelby Renee Burks Ward

Masters Theses

Enforcement is a key feature of the Clean Water Act. The Clean Water Act’s National Pollutant Discharge Elimination System (NPDES) permit program regulates effluent into streams that may impact aquatic life. Yet, authorities do not always enforce permits when violations occur. My research examines macroinvetebrate survey data near NPDES permitted facilities in Kentucky and Tennessee to determine the influence of enforcement actions on aquatic biodiversity. Pre-existing data from the Environmental Protection Agency and state agencies was used to make quantitative and spatial comparisons.

My first study used multiple regression to explore whether enforcement and freshwater community indicators changed together. North …

A Comprehensive Evaluation Of Benthic Invertebrate Communities In The Emory River, Watts Bar Reservoir, Tn, Suzanne Jane Young

Masters Theses

The release of fly ash at the Tennessee Valley Authority (TVA) Kingston Fossil Plant (KIF) on 22 December 2008 discharged approximately 4.1 million cubic meters of coal ash into the adjacent aquatic and terrestrial systems. Previous benthic invertebrate investigations conducted by TVA and collaborative researchers concluded that benthic invertebrates in the Emory River were at moderate risk from ash-related constituents, primarily arsenic, in ash-contaminated sediment that remained in the Emory River following extensive dredging efforts. These conclusions were based on the observation of statistically significant reductions in growth and biomass in laboratory toxicity tests with Emory River sediment. Benthic invertebrate …

Explorations Volume 5 Spring 2015, Department Of Ecology & Evolutionary Biology

EEB Newsletter

No abstract provided.