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Ecology, Phylogenetics, And Conservation Of Draba Asterophora Complex: A Rare, Alpine, Endemic From Lake Tahoe, Usa, Emily Ruth Smith Putnam

Theses and Dissertations

Rare, alpine, endemic species are particularly at risk for extinction. Alpine environments are especially vulnerable to climate change and human impacts, such as ski resort development and snowmaking. Draba asterophora Payson is a rare, alpine species that occurs only in three disjunct mountain-top regions surrounding Lake Tahoe. It is currently threatened by human impacts, such as ski resorts, as well as indirect influences of climate change and therefore in need of better understanding for conservation purposes. Draba asterophora may be able to serve as a case study for other similarly vulnerable, rare, alpine, endemic species with conservation needs. We utilized …

Environmental Regulation Of Tidal Wetland Microbial Communities And Associated Biogeochemistry, Ember Morrissey

Theses and Dissertations

Microbial communities play an essential role in carrying out the biogeochemical cycles that sustain life on Earth, yet we know very little about their ecology. One question of particular interest is how environmental conditions shape microbial community structure (i.e., the types of organisms found in the community and their relative abundance), and whether such changes in structure are related to biogeochemical function. It is the aim of this dissertation to address this question via the examination of carbon (C) and nitrogen (N) cycling in wetland ecosystems, which due to their diverse hydrology have a profound influence on biogeochemical cycles. With …

Rice Injury And Ecology Of The Rice Stink Bug, Oebalus Pugnax (F.) In The Delta Region Of Mississippi, George Agana Awuni

Theses and Dissertations

The rice stink bug, Oebalus pugnax (F.), is an important late season pest of rice that is noted for causing grain yield and quality reductions in the United States. This study investigated rice injury using field cages in two rice cultivars (‘Cocodrie’ and ‘Wells’) at bloom, milk, and soft dough stages and O. pugnax ecology in the Delta Region of Mississippi. Specific objectives were: 1) to determine the impact of adult O. pugnax infestation on rice yield and grain quality at bloom, milk, and soft dough stages of rice development; 2) to determine the impact of adult O. pugnax gender …

Environmental Constraints On Cyanomyophage Abundance In The Subtropical Pacific Ocean, Tiana Maria Pimentel

Masters Theses

Viruses are abundant in the world’s oceans and are thought to be important participants in marine biogeochemical cycling. Of these viruses, cyanophages are considered especially important because they infect and lyse cyanobacteria, which are some of the main primary producers in marine environments. Cyanophages are thought to influence the abundance and diversity of cyanobacterial populations and impart significant mortality, thereby affecting primary productivity and microbial community structure. Despite their ecological relevance, little is known about how environmental factors shape cyanophage abundance and diversity over large temporal and spatial scales. To address this gap in knowledge, seawater samples were collected during …

Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez

Theses and Dissertations - UTB/UTPA

This study investigated the relationship between Anopheles abundance, collection sites and environmental variables in the Lower Rio Grande Valley, South Texas. In addition, species composition in the Lower Rio Grande Valley was determined in 2011. A total of 6772 female mosquitoes were identified to six genera and 27 species. The most prevalent genera collected were Culex (53.9%), Ochlerotatus (25.6%) and Aedes (13.6%). Anopheles mosquitoes were collected using resting boxes during summer 2012 at multiple locations along the Lower Rio Grande Valley. ArcGIS was used to identify land cover characteristics and nearest water sources at mosquito collection sites. Estero Llano Grande …

Winter Waterbird Ecology On The Great Salt Lake, Utah, And Interactions With Commercial Harvest Of Brine Shrimp Cysts, Anthony J. Roberts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Interactions among commercial fisheries and birds have been studied in open ocean ecosystems and at aquaculture facilities. On the Great Salt Lake (GSL), Utah, USA, a commercial harvest of brine shrimp (Artemia franciscana) eggs (i.e. cysts) occurs annually during fall and winter. Coinciding with commercial harvest is the use of the GSL by millions of waterbirds which has the potential to result in conflict among industry and birds. The objectives of my research were to examine fall and winter ecology of birds using the GSL and interactions with the brine shrimp cyst harvest. I examined the influence of temperature and …

Effect Of Prescribed Burning In The Forests Of Buffalo National River, Arkansas, Francis Ndar Onduso

Graduate Theses and Dissertations

Prescribed burning (also referred to as controlled or hazard reduction burning) refers to the use of fire under controlled conditions to achieve a desired end product or goal. However, the nature and magnitude of the changes that result from prescribed burning are still incompletely known, and this is especially true for the forests of the Ozarks of northern Arkansas. The overall objective of the research project described herein was to obtain the data necessary to develop a better understanding of these changes, particularly as they relate to the use of prescribed burning as a management technique in the Buffalo National …

Restraurant Regions : An Ecological Community Based Model Of Restaurant Chain Distribution In The United States, Stephen Griego

Geography ETDs

The scope of this paper is an exercise in regional identification within the geography of the United States. This paper applied a hierarchical clustering methodology to analyze the distribution of restaurants in the landscape. The clustering model utilized in this study is commonly used in analysis of ecological communities. Each restaurant chain was treated as an individual biological species, and the clustering software analyzed it as such. The individual restaurant chain locations were treated as individual samples in the environment. Wards (1963) algorithm was used to group the individual restaurant chain locations into related clusters using simple correlation as the …

Cultural And Ecological Considerations Within The Context Of School Climate, Tamika La Salle

Counseling and Psychological Services Dissertations

School climate has been established as an important construct to measure because of its connections to student psychological, social, and academic outcomes. Existing research has examined school climate in relation to individual (i.e., race and gender) and school level (i.e., teacher characteristics or school size) variables. The current paper presents a cultural-ecological model for research on school climate. The cultural-ecological model of school climate supports future research incorporating a broadened view of culture, extending beyond race and ethnicity, and a more comprehensive examination of ecological contexts such as the family and community in understanding student perceptions of school climate. Within …

Genetic And Ecological Characterization Of Indigoidine Production By Phaeobacter Sp. Strain Y4i, William Nathan Cude

Doctoral Dissertations

The Roseobacter clade is a widely distributed, abundant, and biogeochemically active lineage of marine alpha-proteobacteria. Members of the Roseobacter lineage are prolific surface colonizers in marine coastal environments, and antimicrobial secondary metabolite production has been hypothesized to provide a competitive advantage in colonization. In this work, Phaeobacter sp. strain Y4I was found to produce the water soluble, blue pigment indigoidine via a nonribosomal peptide synthase-based biosynthetic pathway encoded by a novel series of genetically linked genes, termed igiBCDFE. Comparison of wildtype, non-pigmented, and hyper-pigmented Y4I insertional mutants demonstrated a perfect correlation between indigoidine production and the inhibition of Vibrio …

Under Construction: Viewing Manipulated Space, Michael David Farrell Jr.

Theses

North America, the United States in particular, has established an unique and distinct connection to the the wildspaces outside of urban environments. The two spaces, urban and wilderness, are placed in opposition to one another in a sliding valuation scale that is based on the degradation experienced in these urban areas, due to industrialized capitalist means of production, by the inhabitants. These effects are the source of both literary and visual art protests that originate in the 19th century in both generations of the Hudson River School painters, American pastoral writing, philosophy, and photographs. These romanticized views of natural space …

The Effects Of Calcium Concentration And Food Levels On Daphnia, Fawn Goodberry

Biology Theses

Many physiological processes of Daphnia are negatively affected at low calcium concentrations. The concentration of calcium within lake water influences how Daphnia populations will survive and reproduce in natural environments. An experiment was designed to test the effects of calcium concentration and food level on the growth and reproduction of a Daphnia hybrid. Daphnia pulex x Daphnia pulicaria were reared in a soft water medium at three calcium concentrations (2.5mg/L, 1.0mg/L, 0.50mg/L) and high and low food levels (5.6 x 10⁵ and 5.6 x 10⁴ cells of the algae Ankistrodesmus sp.) in a 2 x 3 factorial …

Memory As Ecology In The Poetry Of Tomas Tranströmer, Richelle Jolene Wilson

Theses and Dissertations

The purpose of this study is to explore how memory functions ecologically in the poetry of Tomas Tranströmer. The term ecology is useful because of its connotative associations with the natural world as well as its broader definition of being a network of relationships as they function within and relate to their environment. Throughout his oeuvre, Tranströmer positions memory as being an external presence with which he interacts primarily because he honors it as a living being and he feels a poetic responsibility to it. As such, he grapples with the challenges of representation, particularly the limitations of language. Ultimately, …

Natural Science In Our School Environment : Being Five And Being A Scientist, Danielle L'Heureaux

Graduate Student Independent Studies

This independent master's project is a proposal of an integrated science curriculum for five and six year olds. The curriculum is divided into four units: natural/manmade, living/non-living: animals, living/non-living: plants, and change.

Inorganic Carbon And Nitrogen Utilization In Mixotrophic Ciliates, Donald M. Schoener

Doctoral Dissertations

Mixotrophy is a common nutritional strategy that uses both heterotrophy and photosynthesis. Kleptoplastidic mixotrophs do not make their own plastids but acquire them from their algal prey. Before we can add mixotrophs to standard ecological models we need to understand how much each nutritional mode contributes to mixotrophic growth, and how this balance may be influenced by plastid acquisition, retention, and turnover.

In order to examine the role of captured chloroplasts in the metabolism of the oligotrich ciliate Strombidium rassoulzadegani. I evaluated the uptake and retention of chloroplasts, the ability of two different algae to supply functional chloroplasts, and …

"Radiant Imperfection": The Interconnected Writing Lives Of Robert Bringhurst, Dennis Lee, Tim Lilburn, Don Mckay, And Jan Zwicky, Kostantina Northrup

Electronic Thesis and Dissertation Repository

Over the course of the past two decades, Robert Bringhurst, Dennis Lee, Tim Lilburn, Don McKay, and Jan Zwicky have come to be known as a coterie of ecological writers and ethicists. All five poets have inhabited the Canadian university at various points throughout their careers, and by discussing their ecopoetics in light of their commentary on academic epistemologies and contemporary education in the humanities, this dissertation observes how the poets’ respective approaches to aesthetics, philosophy, and pedagogy are intimately intertwined. By contextualizing the group’s ecopoetics in light of their academic interventions, I argue that their public reputations as ecological …

Public Land And Its Management: Why The Research Is Not Enough, Corinne Calhoun

Pomona Senior Theses

Ecological research, both basic and applied, can inform management decisions on public land in a number of ways. Most importantly, it can illuminate any negative effects of a given land use practice as well as the causes behind that effect. This type of information can be important to a management agency, such as the BLM, with a multi-use mission as these studies indicate under what management regimes a land use is in contradiction with other goals, such as conservation or restoration.

The current body of research, however, is flawed. In order to make fully informed decisions, land managers are in …

Assessment Of Age, Diet, And Growth Of Yellow Perch ( Perca Flavescens) In Cheat Lake, West Virginia, Nate Taylor

Graduate Theses, Dissertations, and Problem Reports

This thesis evaluates population characteristics of yellow perch ( Perca flavescens) in Cheat Lake, West Virginia, and is comprised of two chapters: 1) an introduction and literature review on the biology, ecology, and life history of yellow perch and studies regarding diet growth, and condition and 2) a study examining age and length, summer diet composition, and growth of yellow perch in Cheat Lake, West Virginia. Owing partly to recent mitigation of acidic conditions in the Cheat River watershed, populations of yellow perch and other fishes have increased in Cheat Lake. For this study, I evaluated age and length, summer …

Phosphorus Retention And Transformation In Floodplain Forests Of The Southeastern United States, John A. Navaratnam

Graduate Theses, Dissertations, and Problem Reports

Phosphorus (P) commonly limits productivity in freshwater ecosystems; thus, increased P loading, either in dissolved (DP) or particulate (PP) form, can lead to eutrophication. The central goal of my dissertation research is to understand these biogeochemical mechanisms of P retention and transformation in rivers and streams and their associated FFs in the Atlantic Coastal Plain of the southeastern US (VA, NC, SC, GA).;To assess the nature of P removal during flooding events, I conducted a detailed study of DP and PP forms (inorganic, Pi and organic, Po) in waters from alluvial (AL) and blackwater (BW) FFs. At each FF site, …

Dot Product Graphs And Their Applications To Ecology, Sean Bailey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We will introduce a new tool to visualize the comparison between different birds. This tool will allow users to use any number of measurable traits to see relationships between different birds, both individually and collectively.

Ecology Of Coyotes On The Valles Caldera National Preserve, New Mexico: Implications For Elk Calf Recruitment, Suzanne J. Gifford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Valles Caldera National Preserve (VCNP) managers were concerned about low elk recruitment observed at the same time as an apparent increase in sightings of coyotes and observations of coyote predation on elk calves. The goal of this study was to describe coyotes’ ecological interactions with elk, particularly coyote diet and movements on the Valle Grande, a large grassland meadow in the southeastern portion of the VCNP.

We examined coyote diet by quantifying undigested remains of food items in coyote scats (feces). The most frequent taxa were rodents (montane voles and pocket gophers), elk (adult and calf), insects (grasshoppers and beetles), …

Roads And The Reproductive Ecology Of Hesperidanthus Suffrutescens, An Endangered Shrub, Matthew B. Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We studied the pollination ecology of the endangered Utah desert shrub, shrubby reed-mustard (Hesperidanthus suffrutescens). We also studied the impacts that dust from unpaved roads has on successful reproduction. In addition, we looked at the relationship between the total number of plants, the spacing of plants, and reproduction. We found that shrubby reed-mustard requires pollinators for successful pollination. Pollinators include many small native bees from the genera Andrena, Dialictus, and Halictus. Additionally, we found that reproduction of shrubby reed-mustard is limited, possibly due to scarcity of these bees. We found that dust from the road …

Greater Sage-Grouse Habitat Selection And Use Patterns In Response To Vegetation Management Practices In Northwestern Utah, Stephanie E. Graham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus; sage-grouse) are a sagebrush obligate species and an indicator of sagebrush (Artemisia spp.) habitat quality. Sage-grouse populations have declined across western North America. Fragmentation of landscapes and habitat loss have been identified as factors that negatively impact sage-grouse populations. Wildfires can increase the distribution of invasive plants and contribute to fragmentation and habitat loss across sagebrush ecosystems. Greenstripping has been identified as a technique to reduce the threat of wildfire and subsequent spread of invasive species. Forage kochia (Bassia prostrata) is a semi-shrub that contains a high moisture content year-round, high …

Integrating, Developing, And Testing Methods To Generate More Cohesive Approaches To Biogeographic Inference, Mallory Elizabeth Eckstut

UNLV Theses, Dissertations, Professional Papers, and Capstones

As a fundamental component of the developing discipline of conservation biogeography, broadscale analyses of biotic assembly and disassembly across multiple temporal and spatial scales provide an enhanced understanding of how geologic transformations and climate oscillations have shaped extant patterns of biodiversity. As with any scientific field, there are limitations in the case of biogeographic historical reconstructions. Historical reconstructions are only as robust as the theoretical underpinnings of the methods of reconstruction (including data collection, quality, analysis, and interpretation). Nevertheless, historical reconstructions of species distributions can help inform our understanding of how species respond to environmental change.

My dissertation takes a …

Modeling The Genetic Consequences Of Mutualism On Communities, Carrie E. Eaton

Doctoral Dissertations

Three models of coevolutionary dynamics between mutualistically interacting species are developed. The first is a three loci, haploid model describing a general plant-pollinator system, such as Greya moth and its host plant. In this case, the system will always collapse to a single plant type and pollinator type. In a community with an mutant plant type, it is possible for a host-switch to occur, governed by the initial relative abundance plant type and the pollinator choosiness. In addition, genetic diversity can be maintained if the pollinator has no differential host preference, only adaptation to a host. Next, this model is …

Life History And Morphometric Variation Of Gambusia Nobilis At Bitter Lake National Wildlife Refuge, Alyssa Hopkins

Biology ETDs

The Pecos Gambusia, Gambusia nobilis, is an endangered, live bearing fish inhabiting sinkholes in a restricted range of the Pecos River Watershed in New Mexico and Texas. The sink holes at Bitter Lake National Wildlife Refuge (BLNWR), Roswell, NM create isolated habitats with varying ecological conditions (habitat size, community composition, dissolved oxygen, salinity and pH). This ecological variation imposes unique selective pressures that may shape differences in life history characteristics and morphology between populations. The goals of this research were to characterize seasonal and population variation in 1) life history characteristics, 2) embryo development patterns, 3) morphology and 4) explore …

Environmental Virtue, Callicott And The Land Ethic, John Charles Simpson

Theses

Callicott’s interpretation of Leopold’s land ethic has been criticized as ecofascist and misanthropic. In addition, it has been argued that his principle precept upon which his land ethic rests is vague if not incoherent. In light of these challenges, I suggest a better way to arrive at a land ethic, which deals not with obligations or duties to the land as Callicott’s does but instead with the application of virtues to nature. In this paper, I provide a brief overview of Callicott’s land ethic and then include a few criticisms of the land ethic. Next, I argue for why a …

The Effect Of Ph On The Metal Binding Capabilities Of Exopolymeric Substances From A Marine Benthic Diatom, Vanessa O'Donnell

All Theses And Dissertations

The marine sediment-water interface is a dynamic microenvironment containing diatoms, which produce exopolymeric substance (EPS). EPS has various functions for individual cells and for marine ecosystems. EPS substance is a species-specific composition that has strong absorptive qualities and is able to bind metals from even a very dilute aqueous solution. As industrially derived metals tend to accumulate in marine mudflats, where diatoms are the major EPS producing organisms, it is important to determine how marine benthic diatom EPS will bind with metals. To address the metal binding properties of diatom EPS, Cylindrotheca closteriums’ EPS was isolated by tangential flow filtration, …

Creating Sustainable Economic And Ecological Growth In The Congo Basin: Bushmeat Consumption And Biodiversity Protection, Richelle Lynn Warnock

Masters Theses

This research examines the economic and ecological sustainability of bushmeat hunting in the Congo Basin, specifically the Democratic Republic of Congo and the Republic of Congo. Although bushmeat hunting has provided short term gain for individuals in the region, long term solutions focusing on micro and macro level interventions may provide community wide benefits, while protecting Congo Basin wildlife. Research shows that a focus on the development of key economic sectors such as agriculture, mineral resources and hydroelectricity, as well as the growth of infrastructure may provide viable economic gain for the Congo Basin. Ecotourism and improvements to forest management …

The Religion Of Consumption And Christian Neighbor Love, Christopher Porter

Dissertations

Loyola University Chicago

THE RELIGION OF CONSUMPTION AND CHRISTIAN NEIGHBOR LOVE

Consumerism is a word frequently used in various disciplines to express the variety of attitudes, motivations, and practices found among the middle and upper classes. It drives the global economy and influences individuals' socio-psychological perceptions. Some have gone so far as to call consumerism a religion, yet they have not substantiated this claim. This dissertation offers a framework that accounts for consumerism as a religion both as a person's ultimate concern and as a structuralized belief system. As such, it prescribes moral values that shape how people respond to …