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Divergent Responses Of Cryptic Invasive Watermilfoil To Treatment With Auxinic Herbicides In A Large Michigan Lake, Syndell R. Parks

Masters Theses

Invasive plants are a major concern for environmental managers. Cryptic invasive taxa present additional challenges because of their potential to respond differently to management efforts. Invasive Eurasian watermilfoil (Myriophyllum spicatum) and hybrid watermilfoil (Myriophyllum spicatum x Myriophyllum sibiricum) cannot be reliably distinguished based on morphological characters and are therefore cryptic taxa. Laboratory studies show that on average, hybrid watermilfoil grows faster, branches more, and is less responsive to standard control measures developed for Eurasian watermilfoil. These laboratory results predict less effective control of hybrid watermilfoil in mixed populations treated uniformly with one of these control measures. However, to date there …

The Evolutionary Selective Pressures Exerted On A3 Actinobacteriophages, Cheyenne Weeks-Galindo

Masters Theses, 2010-2019

This study identified evolutionary selective pressures within subcluster A3 actinobacteriophages. These phages are able to infect the clinically important genus Mycobacterium. Understanding the selective pressures on genes in these phage genomes is a step toward understanding the adaptations that result from short-term and long-term associations of phages and bacteria that have been co-evolving for perhaps billions of years. In this study 149 phamilies (phage protein families) of homologous gene sequences were analyzed using Datamonkey. Complete data were obtained for 57 phamilies. Of these, eleven phamilies were affected by recombination, three showed evidence of predominantly diversifying selection, and twenty-four have …

Prioritizing The Management Of Arundo Donax: Recommendations For Removal And Revegetation In California Riparian Habitats, Matthew S. Waterworth

Master's Projects and Capstones

The highly invasive grass species, giant reed (Arundo donax), has been a major contributor to riparian habitat degradation in California for over 50 years. Several modes of vegetative reproduction have allowed this alien species to take advantage of fluvial processes and rapidly spread within California watersheds. A. donax dramatically alters hydrologic regimes, displaces native vegetation, and removes food and habitat for native wildlife. It is widely accepted that removal of this invasive on a watershed scale is critical to restore natural riparian processes and facilitate the reestablishment of native flora and fauna. The following study analyzed the efficacy of …

Utilizing Ecological Connectivity In California Desert Wilderness Preservation, Lauren Kahal

Master's Projects and Capstones

The Wilderness Act of 1964 gave the federal land management agencies—the National Park Service, United States Forest Service, U.S Fish and Wildlife Service, and Bureau of Land Management—the authority to identify, propose, and manage lands as wilderness. Wilderness, once approved by Congress for inclusion in the National Wilderness Preservation System, is offered the highest form of land preservation in the nation. However, the wilderness identification process used by the implementing agencies is based on a half-century old statute with an aging definition of wilderness. While designated wilderness can protect the plant and wildlife communities within its borders from direct anthropogenic …

Dietary Patterns And Prostate Cancer Aggressiveness In African-American And European-American Men, Lara Ryan Schneider

Theses and Dissertations

Several foods and nutrients have been linked to prostate cancer risk, but the effect of overall diet on prostate cancer outcomes is not well understood. Previous research has primarily examined a posteriori dietary patterns in relation to prostate cancer; studies that have used a priori dietary patterns and their relationship with prostate cancer have been inconclusive. Furthermore, racial differences in prostate cancer incidence and aggressiveness are not well understood. Data from the case-only North Carolina-Louisiana Prostate Cancer Project (PCaP) was used to examine the association between overall dietary pattern, as measured by the Mediterranean Diet (MED) score and the Dietary …

Oxidative Stress In Avian Embyros, Toshi Tsunekage

Dissertations

Oxidative stress has been implicated in mediating trade-offs in the evolution of life histories. Oxidative stress results from an imbalance in the production of free radicals and an organism’s antioxidant defenses. Higher metabolic rates associated with more rapid growth and shorter development periods may increase oxidative stress and accumulated cellular damage in embryonic tissues. In my dissertation I explored oxidative stress and antioxidant defenses in avian embryos. I measured levels of oxidative stress in tissues of different stage embryos of Japanese quail (Coturnix japonica), and tested if patterns of lipid peroxidation could be explained by changes in the developing embryo’s …

Connectivity Of Coastal And Oceanic Ecosystems: Pelagic Habitat Use By Juvenile Reef Fishes In The Gulf Of Mexico, Katie Bowen

HCNSO Student Theses and Dissertations

The assemblage structure, abundance, biomass, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program. The results presented here are from a 3-month, continuous sampling series in 2011 in which discrete depth strata from 0 to 1500 m were sampled using a 10-m² MOCNESS midwater trawl. This is the first study to examine pelagic juvenile reef fish distributions across the entire oceanic northern Gulf of Mexico seaward of the continental shelf break after the Deepwater Horizon Oil Spill. …

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 …

Mens Life History, Testosterone, And Health, Louis Alvarado

Anthropology ETDs

Testosterone is hypothesized to mediate life history trade-offs between reproduction and survival in men, promoting mating effort over other forms of investment, which entails energetic and mortality costs. Sexually dimorphic musculature represents one form of somatic investment in mating. Favorable energy availability is posited to promote preferential investment in mating effort through upregulated testosterone production and augmented musculature, whereas nutritional constraint is predicted to downregulate testosterone to facilitate a diminished, thriftier phenotype. Furthermore, life history trajectories influencing mens testosterone levels have important health implications for androgen-sensitive disease. Here, I examine broad features of men's life history and health, and their …

Contribution Of Lianas To Plant Area Index And Canopy Structure In A Panamanian Forest, Maria Elizabeth Rodriguez-Ronderos

Theses and Dissertations

Lianas are an important component of tropical forests, where they reduce tree growth, fecundity and survival. Competition for light among plants may be intense; however the amount of light that lianas intercept is poorly understood. We used a large-scale liana removal experiment to quantify light interception by lianas in a Panamanian secondary forest. We measured the change in plant area index (PAI) and forest structure six weeks after cutting lianas in eight 80x80 m plots and in eight control plots, and then annually for four years. We used ground-based LiDAR to measure the 3-dimensional canopy structure before cutting lianas and …

Ecosystem Response To Recent Climate Change In Alpine Environments, Patrick Shawn Sawyer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent variations in meteorological conditions indicate the earth’s climate is changing in ways that can impact delicate ecological balances in sensitive regions. These impacts threaten the essential services provided by such ecosystems. Determining how climate changes are affecting the biosphere is essential to adapt and mitigate harmful consequences. In order to mitigate the negative effects of climate change and adapt to shifting ecological resource constraints, it is imperative to locate such changes and determine vulnerability of ecological resources to changing environmental conditions.

Identifying climate driven ecological changes faces numerous challenges given the reliance on vegetation indices as the primary measure …

The Impact Of Temperature, Ph And Environmental Heterogeneity On Prokaryotic Diversity In Yellowstone National Park Thermal Springs, Xiaoben Jiang

Biology ETDs

Yellowstone National Park (YNP) is one of the largest and most diverse hydrothermal areas on Earth. Extensive culture-independent studies in YNP thermal springs have shown dramatic taxonomic and metabolic diversity in microbial communities. We conducted a survey of bacterial communities along temperature gradients in three alkaline springs with similar geochemistries at the local scale. With these data, we investigated the influence of environmental variables on bacterial community diversity and assemblages along a broad temperature range using high throughput 454 pyrosequencing. Previous studies have suggested that pH is the driver of microbial diversity in thermal springs among geographical regions or at …

Complex Effects Of Nitrogen Pollution And Grazing On Nectar Resources Of The Adult Bay Checkerspot Butterfly (Euphydryas Editha Bayensis), Nidhi Jain

Master's Theses

Recent anthropogenic increases in atmospheric nitrogen due to urbanization and combustion have had many adverse effects on natural systems, including loss of biodiversity, especially in sensitive habitats. One such region is the serpentine ecosystem of Coyote Ridge in San Jose, CA, the last refuge for recurring populations of the federally threatened Bay Checkerspot Butterfly (BCB) (Euphydryas editha bayensis). Increases in non-native grass cover and decreases in native forb cover (including cover of the BCB’s native larval host plants) have been attributed to the fertilizing effects of increased atmospheric nitrogen deposition. To counteract this effect, grazing has been implemented as a …

Effects Of Small-Scale Substrate Complexity And Heterogeneity On Rocky Intertidal Species Interactions, Sara E. Worden

Master's Theses

The barnacle assemblage in the high rocky intertidal zone has provided an excellent study system to examine species interaction webs. This assemblage consists of a small set of species: barnacles, a variety of macroalgae, and a suite of limpet grazers. Despite the extensive intertidal research occurring along the central California coast, little is known about this specific interaction web and what physical factors may influence it in this region. This study examines the direct, indirect, positive, and negative interactions between the intertidal barnacle Balanus glandula Darwin, the brown seaweed Pelvetiopsis limitata Gardner, and limpet grazers, and how the underlying rock …

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 …

Safe Sleep Education And Staff Compliance, Shayla M. Hadley

The Eleanor Mann School of Nursing Undergraduate Honors Theses

The purpose of this project was to evaluate compliance with the teaching and documentation of safe sleep practices within a pediatric unit. The objective was to increase the percentage of the charts of patients one year of age and younger that have documented safe sleep teaching at the level of compliance with the department policy. This change in compliance was measured by determining the percentage of patient charts having documented safe sleep teaching at the level of compliance prior to the implementation of mandatory staff education as compared to the percentage of charts with documented safe sleep teaching at the …

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 …

Sampling Terrestrial Arthropod Biodiversity: A Case Study In Arkansas, Michael Joseph Skvarla

Graduate Theses and Dissertations

The Interior Highlands is a biodiversity hotspot, with at least 200 known endemic species, but is understudied compared to hotspots, such as the Southern Appalachians. In order to begin to rectify this issue, a nine month study was conducted from mid-March through early December at a 4 ha site at Steel Creek, Buffalo National River, in Newton County, Arkansas. Thirteen collecting methods were employed, including three colors of Lindgren funnel trap, five colors of pan trap, Malaise traps, canopy traps with upper and lower collectors, pitfall traps, and Berlese-Tullgren extraction of leaf litter, which resulted in the collection of 1311 …

Recreation Ecology Of Colorado Fourteeners: An Assessment Of Trail Usage And Impacts, James C. Ewing

Master's Theses

The popularity of climbing Colorado’s 14,000 ft. peaks, or “Fourteeners”, has risen dramatically in recent years, raising important sustainability and management questions. Moreover, groups managing the peaks operate with major capital constraints so their efforts need to be informed, prioritized, and efficient. This paper gauges the dynamics of trail usage, explanatory variables, and recreational impacts across all 58 Fourteeners, and details evaluation adjustments that minimize error and produce results in-step with the resource management framework. Relative to a baseline study completed in 2005, substantial changes occurred in trail usage and impact dynamics. The greatest changes were concentrated on peaks previously …

Associations Of Lifestyle Factors With Bone Accrual In Child And Adolescent Amateur Swimmers, Codruta Andy Collins

Electronic Theses and Dissertations

Maximizing bone mass during growth is important to prevent osteoporosis later in life. Swimming competitively at elite levels during growth does not offer an osteogenic advantage. Swimmers have lower bone mass than athletes who engage in high-impact activities and have similar or lower bone mass than sedentary individuals. Amateur swimmers, who train less intensely than their elite counterparts, may also be at risk of training-related bone mass deficits, but their bone accrual has not been characterized. This dissertation examines determinants of bone accrual over a two-year period in a cohort of 234 Caucasian of 8- to 18-year-old amateur swimmers and …

Population Genetics And Epigenetics Of Two Salt Marsh Plant Species Along An Environmental Gradient, Christy M. Foust

USF Tampa Graduate Theses and Dissertations

Phenotypic plasticity is the ability of a given genotype to exhibit different phenotypes in response to environmental variables, which can impact population level processes. Plasticity of ecologically-relevant traits is important to an organism’s environmental response; however, the underlying mechanisms of plasticity are largely unknown. Ecological epigenetics may offer mechanisms (e.g. DNA methylation) underlying phenotypic plasticity. Epigenetics can be defined as the underlying molecular mechanisms that allow one genotype to exhibit different phenotypes. Differential DNA methylation is one epigenetic mechanism that has been correlated with a number of ecologically-relevant traits; including, differential herbivory in Viola cazorlensis, spinescence in Ilex aquifolium …

Diet Reconstruction And Niche Of Lake Ontario Top Predators And Corresponding Prey Species, James Adam Mumby

Electronic Theses and Dissertations

Lake Ontario supports a diverse offshore fish community consisting of salmonids and forage fish with little known about the resource partitioning and habitat use of these species. To assess this, I used stable isotopes to determine the isotopic trends (forage fishes only), niche structure and overlap of both salmonids and forage fishes. I also estimated the salmonid trophic position (TP) and diet using stable isotopes. Forage fishes had high resource partitioning but was low between Myoxocephalus thompsonii and Cottus cognatus. Regional and temporal discrete subpopulations driven largely by nitrogen were only present in Alosa pseudoharengus, Osmerus mordax and Neogobius melanostomus. …

In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers

USF Tampa Graduate Theses and Dissertations

Limestone dissolution in karst environments is likely due to geochemistry of the water, the actions of microbial communities, and the effect of water flow. We explored the rate of limestone dissolution and will examine here the microbial communities associated with the limestone. A conduit within the brackish cave, Double Keyhole Spring, on the coast of central west Florida was the site of the experiment. PVC pipes (5cm x 16cm) were filled with crushed limestone that was screened to a 1.9cm – 2.54cm size range. There were three treatments (5 replicates each): Control - sealed autoclaved controls with limestone and conduit …

Rna Interference: Potato/Tomato Psyllid, Bactericera Cockerelli, Oral Delivery Of Double-Stranded Rnai Construct, Bijaya Kumar Sharma

Biology Theses

The potato/tomato psyllid, Bactericera cockerelli (Sulc.), is a serious and economically important pest of the potato, tomato and other solanaceous crops. This insect is the putative primary vector of the phytopathogenic bacterium Candidatus Liberibacter solanacearum which causes the Zebra Chip in potato. This disease has caused millions of dollars loss to the potato industry. While traditional management programs have minimized the negative impacts of this disease system, a sustainable alternative to chemical treatment is needed. Management of this pest by downregulation of endogenous mRNA using RNA interference (RNAi) technology is one of the best molecular method available; however, several technical …

Biodiversity And Ecological Dynamics Of Sciophilous Benthic Communities On Artificial Plates: Emphasis On Reef Sponges, Caidra Elizabeth Hassanzada

HCNSO Student Theses and Dissertations

Low light intensity habitats harbor unique sciophilous benthic communities and are a source of novel and unique sponge fauna. However, the community structure of these habitats is poorly studied to date. Thus, this study attempts to understand the composition and structure of sciophilous sponge populations in southeast Florida. Fifty limestone plates were placed on a shallow reef in Fort Lauderdale for two years (2010-2012). To identify the sponge community and their patterns over time, all plates were photographed at the end of each year. Then, samples were taken from each of the live sponge specimens observed on the plates and …

The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai

Dissertations (1934 -)

Anaerobic digestion (AD), the conversion of complex organic matter to methane, occurs through a series of reactions mediated by different guilds of microorganisms. AD process imbalances, such as organic overload or high organic loading rates (OLR), can result in the accumulation of volatile fatty acids (VFA) e.g., propionate, which must be degraded to maintain stable reactor function. VFAs are metabolized by syntrophic fatty-acid degrading bacteria (SFAB) in association with methanogenic archaea (collectively, syntrophic microbial communities, SMC). Despite their indispensable role in AD, little is known about the ecology of SFAB, especially under stressed conditions. To facilitate ecological studies, four quantitative …

Environmental Expertise In The Age Of Research: Institutional Process And Environmental Science In The American Far West, 1950-2014., Nathan D. Woods

Dissertations, Theses, and Capstone Projects

This dissertation focuses on how academic experts have gone about creating university- based programs in Environmental Science (ES). Since the 1940's, with the emergence of the postwar research economy, the U.S higher education system has increasingly become a vector of institutional change, innovation, and economic growth. This has had a dramatic impact on the social role of knowledge and collective expectations for faculty and expert work. In this context, academic experts in the mid 1960's championed a movement to develop university-based programs integrating interdisciplinary environmental research with the expert use of science in decision-making. I pay particular attention to the …

Effect Of The New York City Overdose Prevention Program On Unintentional Heroin-Related Overdose Death, 2000-2012, Anne Elizabeth Siegler

Dissertations, Theses, and Capstone Projects

Background: Drug overdose mortality is the leading cause of injury death in both the United States (US) and New York City (NYC). Heroin-related overdoses make up the majority of overdoses in NYC. Since 2006, when a law was passed that allowed for layperson administration of naloxone, an opioid antagonist, heroin-related overdose deaths have decreased in NYC. No studies to date have investigated a possible association between the implementation of this intervention and heroin-related overdose mortality.

Objectives: To investigate the possible association between overdose prevention programs (OPPs) and heroin-related overdose mortality in NYC, using interrupted time series and geospatial analytic …

Incipient Speciation In Freshwater Fish Species From Two Isolated Watersheds, Paula Gore Miller

Dissertations, Theses, and Capstone Projects

The process of speciation occurs as a result of restricted gene flow between segments of an interbreeding population occupying different geographic areas. This separation may result in isolated populations which undergo genetic and phenotypic changes. The Wisconsin glacial period, which ended approximately 17,500 years ago, dramatically altered the geography of North America. The glacier covered almost the entire North America as it advanced. Areas that were not covered with ice provided suitable habitats (refugia) for relict species that were previously widespread in the northern section of the continent. As the ice sheet retreated, animals and plants were able to return …

Evaluation Of Soil As A Risk Indicator For Human Leptospirosis In Coastal, Rural Ecuador, Chad Allen Weddell

USF Tampa Graduate Theses and Dissertations

Leptospirosis, a zoonotic disease caused by pathogenic spirochete bacteria (family Leptospiraceae, genus Leptospira), is endemic in developing tropical regions of the world. It occurs in epidemics and is endemic in Ecuador where environmental conditions are ideal for maintenance. The role of soil as a long term reservoir has been previously been documented. Geographic Information System (GIS) and Remote Sensing (RS) technology was used in our study to further explore the role of soil as an environmental reservoir and its potential use as a static risk indicator for disease. Red, Green, Blue (RGB) spectral band data from known leptospire …