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Morphological And Molecular Identification And Characterization Of Dry Bean Fungal Root Rot Pathogens In Zambia, Chikoti Mukuma

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Dry bean is among the most important food legume crops for direct human consumption in Latin America and Africa. Recently, root and crown rot (RCR) has emerged as an important production constraint. Root and crown rot often involve fungal complexes. Thus, the straw, detached leaf, cup and stem tests were compared on their ability to detect the most common pathogens reported to be associated with RCR: Fusarium solani, Fusarium oxysporum, Pythium ultimum, Rhizoctonia solani and Macrophomina phaseolina.Significant differences (P

Next Generation Sequencing (NGS), conventional Polymerase Chain Reaction (PCR), and classical fungal culturing methods were compared in identification of …

An Inquiry Into The Pedagogical Implications Of Dewey’S Ecological Thinking, Simon Jorgenson

Occasional Paper Series

My primary purpose is to (re)examine Dewey in the context of contemporary conceptions of ecology and environmental education. With this in mind, I will focus primarily on what Dewey has to say about the natural world, beginning with his general philosophy and moving through several of his educational works.

A Life-History Perspective On The Demographic Drivers Of Structured Population Dynamics In Changing Environments, David N. Koons, David T. Iles, Michael Schaub, Hal Caswell

Wildland Resources Faculty Publications

Current understanding of life-history evolution and how demographic parameters contribute to population dynamics across species is largely based on assumptions of either constant environments or stationary environmental variation. Meanwhile, species are faced with non-stationary environmental conditions (changing mean, variance, or both) created by climate and landscape change. To close the gap between contemporary reality and demographic theory, we develop a set of transient life table response experiments (LTREs) for decomposing realised population growth rates into contributions from specific vital rates and components of population structure. Using transient LTREs in a theoretical framework, we reveal that established concepts in population biology …

Molecular Response Of Spartina Alterniflora To The Deepwater Horizon Oil Spill, Mariano Alvarez

USF Tampa Graduate Theses and Dissertations

Although the “genome as a blueprint” metaphor has been pervasive in biology, recent advances in molecular biology have revealed a complex network of regulatory machinery that dynamically regulated molecular processes in response to environmental conditions. However, these patterns, as well as the evolutionary processes that underlie them, remain understudied in natural conditions. In 2010, the Deepwater Horizon oil spill released an estimated 4.9 million barrels of oil into the Gulf of Mexico, making landfall on salt marsh habitat dominated by the foundation species Spartina alterniflora. Despite the severe impacts to phenotype and fitness, S. alterniflora proved remarkably resilient in …

Gray Bat Migration In Missouri, Cheyenne Leigh Gerdes

Graduate Theses/Dissertations

Migration is an important and understudied aspect of the life histories of many species, particularly bats. Migration impacts conservation efforts, including efforts to manage the impacts of wildlife disease. The federally endangered gray bat (Myotis grisescens) is a migratory species with documented infections by Pseudogymnoascus destructans, the fungus that causes White-nose Syndrome (WNS). To better understand migration as it might relate to WNS, I quantified the timing and location of gray bat movements in Missouri using acoustic detectors and bat banding. I recorded calls at 4 maternity sites from January to May 2015, and used the R package PVAClone to …

A Multidimensional Investigation Of The Niche: Geographic Distributions, Body Size, And Interspecific Interactions Of Late Quaternary North American Canidae, Melissa Irene Pardi

Biology ETDs

A pressing conservation challenge is understanding how organisms will be impacted by climate change. From the paleontological record, we know organisms have options when facing change: they can do nothing, move, or adapt. These responses shape an organism's niche (a foundational concept in biology) that is abiotically constrained, but modified by biotic interactions. The greatest disturbances in recent North American geologic history is the human mediated extinction of megafauna ~11,700 years B.P. and climate change following the last glacial period. We used the fossil record to address ecological questions concerning conservationists; our focus was on Canidae and humans. Species distribution …

Bayesian Methods For Comparing Species Physiological And Ecological Response Curves, Michael B. Ashcroft, Angélica Casanova-Katny, Kerrie Mengersen, Todd N. Rosenstiel, Johanna D. Turnbull, Jane Wasley, Melinda J. Waterman, Gustavo E. Zúñiga, Sharon A. Robinson

Biology Faculty Publications and Presentations

Many ecological questions require information on species' optimal conditions or critical limits along environmental gradients. These attributes can be compared to answer questions on niche partitioning, species coexistence and niche conservatism. However, these comparisons are unconvincing when existing methods do not quantify the uncertainty in the attributes or rely on assumptions about the shape of species' responses to the environmental gradient. The aim of this study was to develop a model to quantify the uncertainty in the attributes of species response curves and allow them to be tested for substantive differences without making assumptions about the shape of the responses. …

Ionic Liquid Extraction Unveils Previously Occluded Humic-Bound Iron In Peat Soil Pore Water, Timothy J. Veverica, Evan S. Kane, Amy Marcarelli, Sarah A. Green

Department of Biological Sciences Publications

Globally, peatland ecosystems store tremendous amounts of C relative to their extent on the landscape, largely owing to saturated soils which limit decomposition. While there is still considerable uncertainty regarding CO₂ production potential below the water table in peatland ecosystems, extracellular Fe reduction has been suggested as a dominant pathway for anaerobic metabolism. However, colorimetric methods commonly used to quantitate Fe and partition between redox species are known to be unreliable in the presence of complex humic substances, which are common in peatland pore water. We evaluated both the standard o-phenanthroline (o-P) Method and an ionic …

The Plight Of Aspen: Emerging As A Beneficiary Of Wolf Restoration On Yellowstone’S Northern Range, John Klaptosky

Aspen Bibliography

No abstract provided.

Plants' Native Distributions Do Not Reflect Climatic Tolerance, Tierney Bocsi, Jenica M. Allen, Jesse Bellemare, John Kartesz, Misako Nishino, Bethany A. Bradley

Biological Sciences: Faculty Publications

Aim: Biogeographers have long known that plant species do not fully encompass their fundamental niche. Nonetheless, in practice, species distribution modelling assumes that plant distributions represent a reasonable approximation of their environmental tolerance. For ecological forecasting, projections of habitat loss due to climate change assume that many species will be unable to tolerate climate conditions outside of those found within their current distributional ranges. We aim to test how well occurrences in the native range approximate the climatic conditions in which plant species can survive.

Location: Continental USA. Methods: We compared the climatic conditions between occurrences in the US native …

Characterization Of The Marine Sponge Amphimedon Compressa Microbiome Across A Spatial Gradient, Renee Michelle Potens

HCNSO Student Theses and Dissertations

Diverse and ecologically important microbial communities (microbiomes) are symbiotic within marine sponges. In this study, the microbiome of Amphimedon compressa from three sample locations (Broward and Dade Counties, Southeast Florida, USA and the Southern Caribbean, Bocas del Toro, Panama) is characterized using 16S rRNA Illumina sequencing. The predominant taxa are Proteobacteria and Cyanobacteria, as expected for Low Microbial Abundance sponges, accounting for over 53% of the total microbiome community. The numbers of Operational Taxonomic Units (OTUs) decrease from Broward County (2,900) to Dade County (2,300) and then Bocas del Toro (1,200). The correlates to a decreasing north-south gradient of …

Assessment Of American White Pelican Predation And Reproductive Success Of Walleye In The Tamarac River, Mn, Jake Graham

Biology Graduate Theses

The Tamarac River is a major tributary of the Red Lakes MN, which provides an economically important multispecies fishery. The river experiences spring spawning migrations of northern pike, walleye, and white suckers. However, limited data exists related to reproductive success of fishes in the river. Furthermore, in the previous decade large congregations of American white pelicans (AWPE) have been observed using the Tamarac River as a foraging ground each spring. Assessing reproductive success of fishes in the Tamarac River provides a more holistic understanding of fish ecology in the river and the importance of the Tamarac River to the Red …

The Effects Of Large Herbivores On Soil Organic Matter Quality In Terrestrial Ecosystems, Adrian Alvarez

Renée Crown University Honors Thesis Projects - All

Understanding the factors that control the natural fluxes of carbon into and out of terrestrial ecosystems is of paramount importance to forecast and adapt to climate change. Soil respiration – the release of carbon dioxide from roots and soil micro-organisms– is considered to be the largest terrestrial source of carbon dioxide. Microbial respiration, the least understood component of soil respiration, is to a great extent determined by soil organic matter quality, reflecting the relative fractions of labile and recalcitrant soil carbon. The goal of this research was to examine how herbivory affects soil organic matter quality across a wide range …

Gaur (Bos Gaurus) Abundance, Distribution, And Habitat Use Patterns In Kuiburi National Park, Southwestern Thailand, Supatcharee Tanasarnpaiboon

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

Population status of gaur (Bos gaurus), a wild cattle, in most habitats where they are present, is still unknown. As the use of camera traps in wildlife studies are widespread, I developed photographic individual identification procedures and utilized encounter histories of gaur individuals from camera trap data to estimate gaur abundance and density using the spatially explicit capture-recapture analysis. The study was conducted at Kuiburi National Park, southwestern Thailand, comprised of dry evergreen forest, moist evergreen forest, and man-modified secondary forest during November 2013- January 2015. I conducted 71 direct observations in a savannah-like habitat area to observe …

Genetic Variation In Long-Term And Short-Term Physiological Changes In Daphnia Magna During Acclimation To High Temperature, Bret L. Coggins

Undergraduate Honors Theses

The aquatic zooplankton crustacean Daphnia magna must be able to tolerate thermal stress in order to survive their native shallow ponds that are susceptible to drastic seasonal and diurnal temperature fluctuations as well as to globally increasing temperatures. Survival in such variable environments requires plastic responses that must include fundamental aspects of Daphnia biochemistry and physiology. Adaptive response to selection favoring such plastic phenotypes requires the presence of genetic variation for plastic response in natural populations. Adverse effects of elevated temperature on aquatic organisms are diverse and so are their plastic responses; among the most severe challenges aquatic organisms face …

Assessing Plant Community Structure In The Upper Las Vegas Wash Conservation Transfer Area, Nevada: The Influence Of Biotic And Abiotic Variables, Amy A. Croft

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ecological communities are complex, the structure of which is composed of interactions between multiple community characteristics and the abiotic and biotic factors shaping them. Because of this complexity, ecological studies are generally limited in scope and size, often dissecting communities into their component parts to examine them piece by piece. While this might be the most practical method to study communities, this approach often neglects other characteristics that, with their inclusion, would provide a more complete picture of community ecology. The studies described in this dissertation were conducted in an effort to synthesize the complexity that is inherent in ecological …

Stable Isotopes And The Ecology And Physiology Of Reptiles, Andrew M. Durso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When animals don’t have enough food, they have to “choose” between “spending” their limited energy on themselves or on their offspring. Biologists think that reptiles can make this choice quickly in response to different environments. But, it can be hard to study these choices because it is hard to convert between, for example, the number of eggs laid and the speed of healing a wound. By using stable isotope chemistry, we can collect more detailed and comparable information about how lizards and other animals spend their limited resources than with any other method. For example, lizards in the wild have …

Comparing Conventional And Noninvasive Monitoring Techniques For Assessing Cougar Population Size In The Southern Greater Yellowstone Ecosystem, Peter D. Alexander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Determining the abundance or density of wildlife populations is needed for informed decision-making by wildlife biologists. Cougars (Puma concolor), however, are a highly secretive species occurring at very low densities across the landscape, and thus their populations are difficult for biologists to accurately assess. The conventional, and most trusted, method entails physically trapping and radio-collaring as many cougars as possible in a population, and then performing a simple count to determine a minimum population size. While accurate, this method is prohibitively expensive, logistically challenging, and behaviorally disruptive to the study animal. Many noninvasive surveying techniques, such as camera …

The Role Of Hydrologic Regimes In Driving Morphologic Divergence And The Trait Compositions Of Fish Assemblages, Lindsey A. Bruckerhoff

Graduate Theses and Dissertations

The hydrologic regime is an important determinant of the ecological integrity of a stream. Hydrologic regimes are defined by the magnitude, timing, frequency, rate of change, and duration of high and low flow events and capture long term patterns of variability and predictability of water movement in a stream. Flow regimes influence many aspects of the biophysical environment in lotic systems; therefore organisms have adapted to natural flow patterns. We investigated how fish have adapted to flow regimes at both a population and community level. In the first study presented in this thesis, we hypothesized fish exhibit phenotypic divergence to …

Translating Ecology, Physiology, Biochemistry And Population Genetics Research To Meet The Challenge Of Tick And Tick-Borne Diseases In North America, Maria Dolores Esteve-Gassent, Ivan Castro-Arellano, Teresa Patricia Feria-Arroyo, Ramiro Patino, Andrew Y. Li, Raul F. Medina, Adalberto A. Pérez De León, Roger Iván Rodríguez-Vivas

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Emerging and re-emerging tick-borne diseases threaten public health and the wellbeing of domestic animals and wildlife globally. The adoption of an evolutionary ecology framework aimed to diminish the impact of tick-borne diseases needs to be part of strategies to protect human and animal populations. We present a review of current knowledge on the adaptation of ticks to their environment, and the impact that global change could have on their geographic distribution in North America. Environmental pressures will affect tick population genetics by selecting genotypes able to withstand new and changing environments and by altering the connectivity and isolation of several …

A Comparative Study Of The Flora And Soils Of Great Duck And Little Duck Islands, Maine, Usa, Luka Negoita, Matthew Dickinson, Glen H. Mittlehauser, N. Rajakaruna

Biological Sciences

Strong environmental gradients and varied land-use practices have generated a mosaic of habitats harboring distinct plant communities on islands on the coast of Maine. Botanical studies of Maine’s islands, however, are generally limited in number and scope. Baseline studies of Maine’s islands are necessary for assessing vegetation dynamics and changes in habitat conditions in relation to environmental impacts imposed by climate change, rising sea levels, invasive species, pests and pathogens, introduced herbivores, and human disturbance. We conducted a survey of the vascular plants and soils of forest, field, and ocean-side communities of Great Duck and Little Duck Islands, ME. These …

Export Of Insect Ecosystem Services From Hayed Native Prairie, Wayne J. Ohnesorg

Department of Entomology: Dissertations, Theses, and Student Research

Natural areas, such as prairie, have the potential to provide the benefits of pest suppression and pollination for agricultural production. In Nebraska, prairie is often used for hay production. The impact of prairie hay production management practices on beneficial arthropods is not well understood. Four prairie hay meadows adjacent to row crop fields were selected in northeast Nebraska. The goal was to assess the impact of haying them on beneficial arthropods and the movement of natural enemies into adjacent crop fields. Three management practices were evaluated for hay harvested from prairie meadows one cut per growing season, two cuts per …

Ecological Studies Of Wolves On Isle Royale, 2015-2016, Rolf O. Peterson, John A. Vucetich

Ecological Studies of Wolves on Isle Royale

Annual Report 2015-2016

Evolutionary Responses Of Invasive Grass Species To Variation In Precipitation And Soil Nitrogen, Monica A. Nguyen, Amy E. Ortega, Quoc L. Nguyen, Sarah Kimball, Michael L. Goulden, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

1.Global climate models suggest that many ecosystems will experience reduced precipitation over the next century and the consequences for invasive plant performance are largely unknown. Annual invasive species may be able to quickly evolve traits associated with drought escape or tolerance through rapid genetic changes.

2.We investigated the influence of five years of water and nitrogen manipulations on trait values in a southern California grassland system. Seeds from two annual grass species (Avena barbata, Bromus madritensis) were collected from experimental plots and grown in a common environment over two generations. We measured 14 physiological, morphological, phenological, and …

Stenocarpella Maydis: Identification, Management, And Population Diversity, Martha P. Romero Luna

Open Access Dissertations

Diplodia ear rot (DER) has been a persistent corn disease across the Midwest, and in recent years it has become an annual problem. The objectives of this study were to i) develop a molecular assay for the identification of Stenocarpella maydis, causal agent of DER, ii) evaluate the effect of crop rotation and tillage on DER severity, iii) determine the survival period of S. maydis in corn residue at different soil depths in a corn field, and iv) identify genetic diversity among S. maydis isolates collected from the Midwestern and Southern United States. The genus Stenocarpella contains two species, S. …

Wildlife Underpasses: Frequency Of Use By Neotropic Mammals In Parque Natural Metropolitano, Panamá City, Panamá, Kelly Russo

Independent Study Project (ISP) Collection

In a world of ever increasing globalization and urbanization, roads present wildlife with a number of challenges. They fragment habitats, disrupt animal movements, impact reproductive success and the fitness of individuals and populations, alter population dynamics, and cause unnatural levels of mortality. Fortunately, the numerous detrimental effects of roads can be alleviated by the proper implementation of mitigation structures, such as underpasses, sky bridges and vegetated overpasses. These mitigation structures are an important source of genetic connectivity, especially in a peri-urban reserve setting. This study seeks to understand what species of mammal utilize the wildlife underpasses below Via La Amistad, …

From Planning To Execution To The Future: An Overview Of A Concerted Effort To Enhance Biological Control In Apple, Pear, And Walnut Orchards In The Western U.S., Vincent P. Jones, Nicholas J. Mills, Jay F. Brunner, David R. Horton, Elizabeth H. Beers, Thomas R. Unruh, Peter W. Shearer, Jessica R. Goldberger, Steven P. Castagnoli, Nadine Lehrer, Eugene R. Milickzy, Shawn A. Steffan, Kaushalya G. Amarasekare, Ute Chambers, Angela N. Gadino, R. Karina Gallardo, Wendy E. Jones

Agricultural and Environmental Sciences Faculty Research

We embarked on a large project designed to help enhance biological control in apple, pear and walnut orchards in the western U.S., where management programs were in the midst of a transition from older organo-phosphate insecticides to mating disruption and newer reduced-risk insecticides. A “pesticide replacement therapy” approach resulted in unstable management programs with unpredictable outbreaks of spider mites and aphids. Our project was designed to provide growers and pest managers with information on the effects of newer pesticide chemistries on a suite of representative natural enemies in both the laboratory and field, potential of new monitoring tools using herbivore-induced …

Bioenergy Harvest, Climate Change, And Forest Carbon In The Oregon Coast Range, Megan K. Creutzburg, Robert M. Scheller, Melissa S. Lucash, Louisa B. Evers, Stephen D. Leduc, Mark G. Johnson

Environmental Science and Management Faculty Publications and Presentations

Forests provide important ecological, economic and social services, and recent interest has emerged in the potential for using residue from timber harvest as a source of renewable woody bioenergy. The long-term consequences of such intensive harvest are unclear, particularly as forests face novel climatic conditions over the next century. We used a simulation model to project the long-term effects of management and climate change on above- and below ground carbon storage in a watershed in northwestern Oregon. The multi-ownership watershed has a diverse range of current management practices, including little-to-no harvesting on federal lands, short-rotation clear-cutting on industrial land, and …

Pharmaceutical Contaminants As Stressors On Rocky Intertidal And Estuarine Organisms: A Case Study Of Fluoxetine, Joseph Richard Peters

Dissertations and Theses

Contaminants such as pharmaceuticals are of increasing concern due to their ubiquitous use and persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations. Also scarce in the literature is examination of whole organism effects …

Population Structure, Genetic Diversity, Geographic Distribution, And Morphology Of Two Boechera (Brassicaceae) Parental Species (Boechera Thompsonii And Boechera Formosa) And Of Their Resultant Hybrid Boechera Duchesnensis, Christina Elizabeth Fox Call

Theses and Dissertations

Background: Over the relatively short period of its evolutionary history, Boechera (Brassicaceae) has undergone rapid radiation that has produced 70+ morphologically distinct, sexual diploids. However, reproductive isolation has moved more slowly than morphological divergence in this group and the diploids appear to hybridize frequently where they coexist. Boechera duchesnensis appears to be the result of hybridization between its putative parents Boechera thompsonii and Boechera formosa. Objectives: The objectives of this study are to (i) analyze and document genetic diversity patterns in the population structure, - including allelic and heterozygosity frequencies - of B. thompsonii and B. formosa …