Digital Commons Network^™

Algal Coverage Detection And Classification Using Envi: Correlation With Dissolved Oxygen Levels In Elkhorn Slough, Ca, Jason Dawson

All HCAS Student Capstones, Theses, and Dissertations

Estuaries are exposed to varying stressors, whether they be physical, chemical, or environmental. The most notable of stressors is eutrophication of coastal and inland ecosystems. This is a result of increased supply of nutrients fueling production within the system. One outcome of this increased nutrient load to the system is that of algal blooms. These blooms can impact the aesthetic appearance and degrade the quality of health of the system. Many of these coastal zones and waterways are critical habitats for many biological (some endangered) species and serve as recreational areas for human populations. Elkhorn Slough, California is one of …

A Shark Conservationists Toolbox: Current Dna Methods And Techniques Aiding In The Conservation Of Sharks, Arianna N. Nixon

All HCAS Student Capstones, Theses, and Dissertations

Elasmobranchs are important members of their community. Many sharks are important apex predators that help maintain the health of their ecosystem. However, shark populations are globally declining. This is partially due to the fact that sharks are highly targeted for their fins, meat, liver oil, teeth, and skin. However, they are also killed from anthropogenic effects such as habitat destruction and pollution. Most shark species have life history characteristics that also make them more vulnerable to overfishing. Sharks are also difficult to study due to their elusive nature and identification issues. That is why molecular tools are increasingly becoming important …

Salt Marsh Dynamics In A Period Of Accelerated Sea Level Rise, Sergio Fagherazzi, Giulio Mariotti, Nicoletta Leonardi, Alberto Canestrelli, William Nardin, William S. Kearney

Faculty Publications

Salt marshes are dynamic systems able to laterally expand, contract, and vertically accrete in response to sea level rise. Here, we present the grand challenges that need to be addressed to fully characterize marsh morphodynamics. The review focuses on physical processes and quantitative models. Without predictive models, it is impossible to determine the future marsh evolution under accelerated sea level rise. In these models, one of the challenges is to resolve both horizontal and vertical dynamics within the same framework. Vertically, the marsh has to accumulate enough material to contrast rising water levels. Horizontally, marsh erosion at the ocean side …

Mathematical Modeling, Analysis, And Simulation Of Cholera Dynamics, Chayu Yang

Masters Theses and Doctoral Dissertations

We propose multiple models to investigate the transmission dynamics of cholera. At first, we consider the intrinsic growth of cholera bacteria in cholera transmission and find that the regular threshold dynamics take place if the intrinsic growth is logistic; there are multiple endemic equilibria if the growth exhibits Allee effects, which may lead to backward bifurcation and forward hysteresis. In addition, we introduce a multi-scale modeling framework. At the population level, a Susceptible-Infected-Recovered (SIR) model for the between-host transmission of cholera is employed. At the individual host level, the evolution of the pathogen within the human body is incorporated. The …

Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata, Kadeem J. Gilbert, Leonora S. Bittleston, Mark Arcebal K. Naive, Anthony E. Kiszewski, Perry Archival C. Buenavente, David J. Lohman, Naomi E. Pierce

Biology Faculty Publications and Presentations

Elevation is an important determinant of ecological community composition. It integrates several abiotic features and leads to strong, repeatable patterns of community structure, including changes in the abundance and richness of numerous taxa. However, the influence of elevational gradients on microbes is understudied relative to plants and animals. To compare the influence of elevation on multiple taxa simultaneously, we sampled phytotelm communities within a tropical pitcher plant (Nepenthes mindanaoensis) along a gradient from 400 to 1200 m a.s.l. We use a combination of metabarcoding and physical counts to assess diversity and richness of bacteria, micro-eukaryotes, and arthropods, and …

Variation In Tundra Plant Traits Across A Latitudinal Gradient, Katlyn Rose Betway

Masters Theses

High latitude regions are warming faster than most regions. Studies documenting change in plant cover due to warming have reported that graminoids, deciduous shrubs, and evergreen shrubs are increasing in some regions of the Arctic, but not at others. Mixed responses to warming have caused researchers to shift towards an emphasis on functional traits of individual species rather than their growth forms. This thesis focuses on ten measured plant functional traits for twelve arctic species at three regions spanning a latitudinal gradient in northern Alaska (Utqiaġvik, Atqasuk, and Toolik Lake). We compare mean trait values across the three regions for …

Area-Level Landfill Density And Asthma Prevalence In Urban Texas Areas, Jessica Meighan Herrin

Dissertations and Theses (Open Access)

Environmental exposures, especially air pollutants, pose a threat for an increase in asthma prevalence. In particular, hydrogen sulfide (H2S) gas can cause severe health effects closely resembling asthmatic symptoms. Ambient concentrations of H2S gas correlates with the amount of solid waste found in landfills. The potential for adverse health risks associated with H2S emitted from landfills is of concern for those populations living in close proximity to landfills. Asthma is one of the adverse health effects that can occur due to H2S exposure. However, there is a lack of detailed studies characterizing possible associations between the density of landfills and …

The Effects Of Elevation On Foraging Behavior Of Bats In Southern Appalachia, Victoria Long

Electronic Theses and Dissertations

There are limited studies on bat activity in higher elevations in the Appalachian region. Levels of bat activity were compared in south central Appalachia at low (< 914.4 m) and high (> 1, 524 m) elevations in open, forest edge, and riparian habitats. Additionally, habitat suitability was modeled for a common species, big brown bat (Eptesicus fuscus). The study started May 27^th 2019, and sites were monitored biweekly until October 2^nd 2019. Six species and one genus were recorded during the study. Species from the Myotis genus were grouped together because of similar call characteristics. Results show that species were significantly more …

Consequential Saints: A Preliminary Study Of Jazz And Religion In New Orleans, David Baker

Dissertations

The moral ecosystem of New Orleans at the beginning of the twentieth century offers a unique opportunity for jazz to function and be observed beyond positivist definitions of music. The common narrative often cites religion and morality as peripherally influencing factors in the development of jazz but frequently disregards the impact of New Orleans’ atypical religious milieu and its influence on local culture. While recent research exists that studies the nuanced role of identity, phenomenology, and culture in shaping early jazz, the influence of New Orleans’ unusual form of morality and religion is subsequently ignored. Understanding the birth of jazz …

Analyzing The Von Neumann Entropy Of Contact Networks, Thomas J. Brower

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When modeling the spread of disease, ecologists use ecological or contact networks to model how species interact with their environment and one another. The structure of these networks can vary widely depending on the study, where the nodes of a network can be defined as individuals, groups, or locations among other things. With this wide range of definition and with the difficulty of collecting samples, it is difficult to capture every factor of every population. Thus ecologists are limited to creating smaller networks that both fit their budget as well as what is reasonable within the population of interest. With …

Kudos And K.O.M.'S: The Effect Of Strava Use On Evaluations Of Social And Managerial Conditions, Perceptions Of Ecological Impacts, And Mountain Bike Spatial Behavior, Noah E. Creany

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Smartphone based self-tracking fitness applications (apps) like Strava are increasingly becoming a part of recreation experiences in parks and protected areas (PPAs). Recreation research has employed smartphone GPS tracking (SGT) and volunteered geographic information (VGI) to study visitor behavior in PPAs, but little is understood about how smartphones or fitness apps affect visitor perceptions and behavior during their experience.

The first chapter of this thesis is a literature review of recreation survey and behavior research, social-psychology and technology use theory, gamification, and mountain bike social science and recreation-ecology research. The second chapter is formatted for submission to the Journal of …

Ecoacoustic Methods For Multi-Taxa Animal Surveys In The Amazon, Leandro A. Do Nascimento

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tropical regions host most of the biodiversity found on Earth, but these species-rich areas are constantly threatened by human development and other disturbances that put this diversity of life forms at risk. To avoid extirpations of animal and plant species, scientists and managers rely on accurate monitoring techniques to retrieve information about population trends. This task is not easy, especially in the tropics, where there is often a lack of personnel to conduct surveys, a lack of funding, and the areas are so extensive that many countries need to be involved in monitoring (e.g., Amazon biome). For this reason, scientists …

Assessing The Impact Of Restored Wetlands On Bat Foraging Activity Over Nearby Farmland, Philip Allagas

Electronic Theses and Dissertations

Up to 87% of the world’s wetlands have been destroyed, considerably reducing ecosystem services these wetlands once provided. More recently, many wetlands are being restored in an attempt to regain their ecosystem service. This study seeks to determine the effects of restored wetlands on local bat habitat use. Bat activity was found to be significantly higher around the wetlands when compared to distant grassy fields; however, no significant difference was found among the restored wetlands and a remote cattle farm containing multiple water features. Geospatial models of bat distribution and bat foraging were produced using machine learning that showed higher …

Age And Growth Of Predatory Mesopelagic Fishes In A Low-Latitude Oceanic Ecosystem, Natalie Slayden

All HCAS Student Capstones, Theses, and Dissertations

Mesopelagic and bathypelagic fishes provide important global ecosystem services, such as carbon sequestration via the biological pump and provision of food for economically important (billfishes and tuna) and federally protected (cetaceans and seabirds) species. These attributes are becoming increasingly recognized, while simultaneously mesopelagic fisheries are becoming of interest for direct harvest as coastal fisheries have become overexploited. Additionally, climate change, ocean acidification, and seabed mining threaten deep-sea fishes. With increasing interest in deep-sea fisheries and anthropogenic threats, age and growth information on these fishes is necessary for management and conservation. Currently ecosystem models lack data such as sexual maturity and …

Volume 4, Chapter 8-6: Tropics: Epiphylls, Janice M. Glime, Tamás Pócs

Bryophyte Ecology Subchapters

No abstract provided.

From Tangled Banks To Toxic Bunnies; A Reflection On The Issues Involved In Developing An Ecosystem Approach For Environmental Radiation Protection, Carmel E. Mothersill, Deborah H. Oughton, Paul N. Schofield, Michael Abend, Christelle Adam-Guillermin, Kentaro Ariyoshi, Nicholas A. Beresford, Andrea Bonisoli-Alquati, Jason Cohen, Yuri Dubrova, Stanislav A. Geras’Kin, Tanya Helena Hevrøy, Kathryn A. Higley, Nele Horemans, Awadhesh N. Jha, Lawrence A. Kapustka, Juliann G. Kiang, Balázs G. Madas, Gibin Powathil, Elena I. Sarapultseva, Colin B. Seymour, Nguyen T.K. Vo, Michael D. Wood

School of Biological and Marine Sciences

No abstract provided.

Seasonal Variation Of Bacterial Diversity Along The Marine Particulate Matter Continuum, Mireia Mestre, Juan Höfer, M. Montserrat Sala, Josep M. Gasol

Research outputs 2014 to 2021

© Copyright © 2020 Mestre, Höfer, Sala and Gasol. Seasonal dynamics of ocean prokaryotic communities in the free-living fraction have been widely described, but less is known about the seasonality of prokaryotes inhabiting marine particles. We describe the seasonality of bacterial communities in the particulate matter continuum by sampling monthly over two years in a temperate oligotrophic coastal ecosystem and using a serial filtration (including six size-fractions spanning from 0.2 to 200 μm). We observed that bacterial communities in the particulate matter continuum had annual changes following harmonic seasonal oscillations, where alpha, beta, and gamma diversity increased during the warm …

A Chemical Investigation Of Three Antarctic Tunicates Of The Genus Synoicum, Sofia Kokkaliari

USF Tampa Graduate Theses and Dissertations

Marine invertebrates, mainly sponges, tunicates and corals, have in the past few decades attracted the interest of the scientific community in regard to their secondary metabolites and their potential as leads in drug discovery. The genus Synoicum is comprised of multiple organisms found in both deep and shallow waters, tropical and cold environments around the world. The majority of the members of this genus that have been investigated can be found in shallow tropical waters due to the ease of accessing and collecting them. Of the cold environments, Antarctica is a representative of the environments where members of the Synoicum …

Sex Differences In Age-Related Disease, Matthew Robert Schwartz

Anthropology ETDs

Life history theory posits the evolution of sex-biased traits through asymmetries in the costs of reproduction. The research presented here evaluated the downstream effects of sex-biases in two age-related disease profiles: tooth loss, in which females exhibit a higher disease burden, and melanoma, in which females have a survival advantage.

Among the Tsimane, a natural fertility population of forager-horticulturalists with a high lifetime fertility and no access to oral healthcare, females lose more than males and around half a tooth per child. Parity accounts for 1.2\% of variation in tooth loss within females, but no variation in tooth loss in …

Determination Of Adenosine, Cordycepin And Ergosterol Contents In Cultivated Antrodia Camphorata By Hplc Method, C.-Y. Chang, M.-Y. Lue, T.-M. Pan

Journal of Food and Drug Analysis

The concentrations of adenosine and cordycepin, 3'-deoxyadenosine in the hot water extract and ergosterol in the ethanol extract of a cultivated Antrodia camphorata were measured by high performance liquid chromatography (HPLC) method. The procedure were carried out on a reversed-phase C18 column by linear gradient elution, using four eluents as mobile phase and by isocratic elution, using 100% methanol as mobile phase, respectively. The analysis was completed within 20 min. The application of this method for quantitation of adenosine and cordycepin in 5-L and 100-L fermentation from two A.camphorata strains BCRC 35396 and BCRC 35398 were described. Comparison of adenosine, …

Ecology Of The Roseau Cane Scale (Nipponaclerda Biwakoensis, Hemiptera: Aclerdidae) In Coastal Louisiana, Leslie Alejandra Aviles Lopez

LSU Master's Theses

Common reed, Phragmites australis, is the dominant plant in the Mississippi River Delta (MRD), Louisiana. Phragmites australis stands reduce soil erosion from wave action, protect the oil infrastructure, and freshwater habitats. In the fall of 2016, widespread reed die-backs in the MRD were associated with outbreaks of an invasive scale Nipponaclerda biwakoensis (Hemiptera: Aclerdidae). Due to the recent detection of the scale, there was limited knowledge of its ecology in the adventive range, and its impacts on P. australis lineages. Therefore, the objectives of my thesis were to determine (1) the host specificity of the N. biwakoensis in important economic …

Insufficient Sun Exposure Has Become A Real Public Health Problem, Lars Alfredsson, Bruce K Armstrong, D. Allan Butterfield, Rajiv Chowdhury, Frank R. De Gruijl, Martin Feelisch, Cedric F. Garland, Prue H. Hart, David G. Hoel, Ramune Jacobsen, Pelle G. Lindqvist, David J. Llewellyn, Henning Tiemeier, Richard B. Weller, Antony R. Young

Chemistry Faculty Publications

This article aims to alert the medical community and public health authorities to accumulating evidence on health benefits from sun exposure, which suggests that insufficient sun exposure is a significant public health problem. Studies in the past decade indicate that insufficient sun exposure may be responsible for 340,000 deaths in the United States and 480,000 deaths in Europe per year, and an increased incidence of breast cancer, colorectal cancer, hypertension, cardiovascular disease, metabolic syndrome, multiple sclerosis, Alzheimer's disease, autism, asthma, type 1 diabetes and myopia. Vitamin D has long been considered the principal mediator of beneficial effects of sun exposure. …

Hiv Treatment As Prevention: The Key To An Aids-Free Generation, M.W. Hull, J.S.G. Montaner

Journal of Food and Drug Analysis

The presence of elevated human immunodeficiency virus (HIV) viral load within blood and genital secretions is a critical driver of transmission events. Long-term suppression of the viral load to undetectable levels through the use of antiretroviral therapy is standard practice for the clinical management of HIV. Antiretroviral therapy therefore can play a key role in curbing HIV transmission. The results of a randomized clinical trial and several observational studies have now confirmed that antiretroviral therapy markedly decreases the risk of HIV transmission. Mathematical models and population-based ecologic studies suggest that further expansion of antiretroviral coverage within current guidelines can play …

Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel

LSU Doctoral Dissertations

Floodplain forest species diversity is driven, in part, by variation in disturbance regime. Flood patterns create heterogeneity in microsite quality from small differences in elevation across a floodplain which, in turn, influence flood timing and duration. Differences in species’ regeneration niches in relation to hydrologic patterns can account for long-term coexistence of various species. In the past century floodplain forests have exhibited a wide range of changes in stand development and species composition as a result of altered hydrology in rivers and floodplains. I evaluated the role of regeneration in floodplain forest systems of the Lower Mississippi River Alluvial Valley …

The Mosaic Ice Floe: Sediment-Laden Survivor From The Siberian Shelf, Thomas Krumpen, Florent Birrien, Frank Kauker, Thomas Rackow, Luisa Von Albedyll, Michael Angelopoulos, H. Jakob Belter, Vladimir Bessonov, Ellen Damm, Klaus Dethloff, Jari Haapala, Christian Haas, Carolynn Harris, Stefan Hendricks, Jens Hoelemann, Mario Hoppmann, Lars Kaleschke, Michael Karcher, Nikolai Kolabutin, Ruibo Lei, Josefine Lenz, Anne Morgenstern, Tim Stanton, For Full Author List, See Comments Below

Faculty Research, Scholarly, and Creative Activity

In September 2019, the research icebreaker Polarstern started the largest multidisciplinary Arctic expedition to date, the MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) drift experiment. Being moored to an ice floe for a whole year, thus including the winter season, the declared goal of the expedition is to better understand and quantify relevant processes within the atmosphere-ice-ocean system that impact the sea ice mass and energy budget, ultimately leading to much improved climate models. Satellite observations, atmospheric reanalysis data, and readings from a nearby meteorological station indicate that the interplay of high ice export in late winter …

Distribution Of Vegetation Types In Bayinbuluk Alpine Grassland, Y. K. Hu, K. H. Li, W. L. Li, G. G. Gao, Y. M. Gong

IGC Proceedings (1977-2023)

No abstract provided.

Insights To Gray Seal (Halichoerus Grypus) Foraging Ecology From Stable Isotope And Dna Metabarcoding Analyses, Keith Michael Hernandez

LSU Doctoral Dissertations

The enactment of wide-ranging conservation laws in the United States enabled the recovery of many marine mammal species. However, as many species have surpassed predicted recovery goals, there is an increasing number of marine mammal-human interactions. For example, in the northeast US, the recovery of gray seals (Halichoerus grypus atlantica), coupled with declines in commercially important fishery species, has prompted discussions of revised management, and potentially lethal control measures. Much of this concern stems from seal-fisheries interactions, which necessitates an understanding of seal diets and foraging ecology. However, existing research is out of date and reliant primarily on …

Investigating The Direct And Indirect Effects Of Forest Fragmentation On Plant Functional Diversity, Jenny Zambrano, Norbert J. Cordeiro, Carol Garzon-Lopez, Lauren Yeager, Claire Fortunel, Henry J. Ndangalasi, Noelle G. Beckman

Biology Faculty Publications

Ongoing habitat loss and fragmentation alter the functional diversity of forests. Generalising the magnitude of change in functional diversity of fragmented landscapes and its drivers is challenging because of the multiple scales at which landscape fragmentation takes place. Here we propose a multi-scale approach to determine whether fragmentation processes at the local and landscape scales are reducing functional diversity of trees in the East Usambara Mountains, Tanzania. We employ a structural equation modelling approach using five key plant traits (seed length, dispersal mode, shade tolerance, maximum tree height, and wood density) to better understand the functional responses of trees to …

Effects Of Hurricane Harvey On The Trophic Status Of Juvenile Sport Fishes (Cynoscion Nebulosus, Sciaenops Ocellatus) In An Estuarine Nursery, Philip Matich, Kaya B. Moore, Jeffrey D. Plumlee

Faculty Publications

Understanding the implications of environmental disturbance is of growing importance as climate change and extreme weather events increasingly threaten estuaries and other coastal ecosystems. Among species at risk in estuarine habitats, sport fishes are of particular interest to conservation and management agencies, because of their ecological and economic value. Here, we evaluate the effects of Hurricane Harvey on the abundance, diet, and body condition of age-0 red drum (Sciaenops ocellatus) and spotted seatrout (Cynoscion nebulosus) in Powderhorn Lake, a nearshore estuary in Texas, USA. Catch data from seines indicated that the abundances of age-0 red drum and spotted seatrout were …

Associating Landscape Variables With Nesting Occupancy And Success Of Songbirds Using Nest Boxes In Semi-Urban Greenspaces, Amanda Preece

AES Theses

Habitat fragmentation and loss of biodiversity due to urbanization is happening at a rapid pace. Greenspaces within our cities can provide habitat for native species, and effective management of urban and semi-urban parks is an increasingly important way to support these species. I compared landscape metrics surrounding nest boxes used by five avian species in four semi-urban parks of central coastal California, USA, to determine which land cover elements best predicted nest box occupancy and success. Five species were included in this study – Ash-throated Flycatcher (Myiarchus cinerascens), Chestnut-backed Chickadee (Poecile rufescens), Oak Titmouse (Baeolophus …