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Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel
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 …
Thoreau's Melancholia, Walden's Friendship, And Queer Agency, Julia Morgan Leslie
Thoreau's Melancholia, Walden's Friendship, And Queer Agency, Julia Morgan Leslie
LSU Doctoral Dissertations
Walden queers its readers. While many have investigated Thoreau’s queerness, there has been little notice of Walden’s queerness. This project begins with a situational analysis that identifies the melancholic antecedents of Walden in Thoreau’s life and his choices that led to the illumination of his melancholia. Thoreau had already been experimenting with what Branka Arsić identified as “literalization.” Nevertheless, a period of crisis, detailed by Robert Milder, made him aware of what Nicolas Abraham and Maria Torok have referred to as the melancholic’s blind skill of “demetaphorization.” I suggest that Thoreau exploited this skill to produce Walden’s unique …
Dynamics Of Resprouting And Forest Regeneration Following Anthropogenic Land Use In The Central Amazon Basin, Scott Lawrence Kosiba
Dynamics Of Resprouting And Forest Regeneration Following Anthropogenic Land Use In The Central Amazon Basin, Scott Lawrence Kosiba
LSU Doctoral Dissertations
Tree mortality is increasing with the effects of climate change and drought across the Amazon Basin while intense fires are becoming more prevalent. Tropical moist forest trees generally lack adaptations that protect against mortality during an intense fire, so anthropogenic burning typically kills high percentages of trees. Following disturbances where prescribed burning is used to limit woody encroachment and to fertilize the soil, abandoned land in central Amazonia becomes dominated by the pioneer tree genus, Vismia. Although the mechanisms by which Vismia comes to dominate previously-burned areas are not known, previous studies on anthropogenic land use and forest succession …
Vegetation Influences Microbial Community Structure And Methane Emissions In Southeastern Louisiana Wetlands, Anthony Jason Rietl
Vegetation Influences Microbial Community Structure And Methane Emissions In Southeastern Louisiana Wetlands, Anthony Jason Rietl
LSU Doctoral Dissertations
Methane has a warming potential 28 times that of carbon dioxide and has been increasing in the Earth’s atmosphere since 1750. An understanding of the dynamics of methane emissions from natural sources is becoming increasingly important as we may need to mitigate emissions from these sources in the future to help reduce the effects of climate change. Wetlands are the single largest natural source of methane; however, little attention has been given to how plant species, biota, and interactions between above and belowground communities and microbial communities may affect methane emissions. First, microbial community structure and function was assessed for …
Comparative Population Genomics Of Neotropical Forest Birds, Michael Gaston Harvey
Comparative Population Genomics Of Neotropical Forest Birds, Michael Gaston Harvey
LSU Doctoral Dissertations
The causes and implications of differences in geographic variation across species are generally poorly understood, but comparative studies have the potential to provide better understanding of what factors predispose species to undergo population divergence and whether population divergence has lasting evolutionary impacts. Here, I examined geographic variation in birds using molecular data from across the genome. I characterized genetic diversity, estimated population history, and tested for impacts of landscape history as well as ecological traits on genetic parameters. I found evidence that diverse historical processes have led to present-day genetic variation in Neotropical bird species, including divergence, population expansion, migration, …
Model-Based Tests Of Historical Demography And Species Delimitation In The Caribbean Coral Reef Sponge Callyspongia, Melissa Barrett Debiasse
Model-Based Tests Of Historical Demography And Species Delimitation In The Caribbean Coral Reef Sponge Callyspongia, Melissa Barrett Debiasse
LSU Doctoral Dissertations
Coral reefs are the most productive and species rich ecosystems in the ocean yet we lack knowledge about the distribution of genetic variation the within and among reef species, particularly for the sponges (Porifera). My dissertation describes how genetic variation at mitochondrial and nuclear genes is partitioned among and within species in the sponge genus Callyspongia. I compared patterns of genetic diversity and population subdivision in the mitochondrial and nuclear genomes of one species, C. vaginalis, in Florida (Chapter 2). Previous work revealed three divergent mitochondrial lineages, but nuclear alleles did not correspond to either mitochondrial clade or geography. Coalescent …
Model-Based Approaches To Discovering Diversity : New Implementations, Tests Of Adequacy And An Empirical Application To Central American Diptera, Noah M. Reid
LSU Doctoral Dissertations
Most of the earth’s biodiversity is unknown to science. With global climate change set to drastically alter its distribution, it is imperative to catalogue it and understand its function in order to preserve it and better understand how this change will impact humanity. Recent technological and statistical advances have in theory made possible increasingly rapid discovery and description of diversity. The statistical properties and performance of these new approaches are still poorly known, however, their integration with complementary methods from disparate disciplines has not been achieved. In this dissertation we present three chapters of original research that advance these areas …
Amd&Art: Performativity And Participation In Ecological Remediation, Travis Paine Brisini
Amd&Art: Performativity And Participation In Ecological Remediation, Travis Paine Brisini
LSU Doctoral Dissertations
In this study, I examine and theorize AMD&ART, an artwork devoted to treating polluted water in Vintondale, PA. AMD&ART is much more than simply a water treatment facility, however. Each chapter of this document examines AMD&ART through the lens of a different body of scholarly literature: the literature associated with land art, Systems Theory, Network Theory, Companion Specieshood and others. The theoretical focus of this paper is the emergent importance of the concept of performativity—“that reiterative power of discourse to produce the phenomena that it regulates and constrains” (Butler, Bodies 2)—in the deconstruction of the binary division of “nature” and …
Influences Of Landscape Characteristics On The Nesting Ecology Of Female Wild Turkeys And Behavior Of Raccoons, Michael E. Byrne
Influences Of Landscape Characteristics On The Nesting Ecology Of Female Wild Turkeys And Behavior Of Raccoons, Michael E. Byrne
LSU Doctoral Dissertations
Nest predation is the principle source of reproductive failure in many bird species. Understanding nest predation requires knowledge of interactions between landscape characteristics, and the ecology and behavior of birds and local nest predators. I studied nesting ecology and multi-scale habitat selection of female wild turkeys and the habitat selection and searching behaviors of raccoons, an important nest predator, in a bottomland hardwood forest in Louisiana. My objective was to evaluate the relationships between habitat, wild turkey nest site selection, and raccoon foraging behavior. I used first-passage time (FPT) analysis on nightly foraging tracks of raccoons during the turkey nesting …
Connections Between Individual Dispersal Behavior And The Multi-Scale Distribution Of A Saproxylic Beetle, Heather Bird Jackson
Connections Between Individual Dispersal Behavior And The Multi-Scale Distribution Of A Saproxylic Beetle, Heather Bird Jackson
LSU Doctoral Dissertations
Species incidence results from a complex interaction among species traits (e.g., mobility and behavior), intra- and inter-specific interactions, quality and configuration of the landscape, and historical events. Determining which factors are most important to incidence is difficult because the multiple processes affecting incidence operate at different temporal and spatial scales. I conducted an empirically-based study relating individual behavior (dispersal, habitat selection, and intra-specific interactions) with hierarchically-organized environmental filters to predict the incidence of Odontotaenius disjunctus (Passalidae), a saproxylic (=decayed wood dependent) beetle common to eastern North American forests, at multiple spatial scales. In dispersal experiments, O. disjunctus movement was faster …
Art Informing Science Education: The Potential Contributions Of Ornithological Illustration To Ecology Education, Vanessa Hunt
Art Informing Science Education: The Potential Contributions Of Ornithological Illustration To Ecology Education, Vanessa Hunt
LSU Doctoral Dissertations
Birds serve as an excellent group of organisms from which to introduce the study of ecology, being of inherent aesthetic interest to many otherwise uninterested in science, and are also ubiquitous in the immediate environment of many students. By extension, images of birds might serve as a valuable resource for the ecology educator, and bird artists – as a subset of ecologists - might provide useful models for expertise in ecology. This study examines the potential contributions of bird artists and bird art to education in ecology at the high school and college level. Eight contemporary bird artists were interviewed …
Soils Of Regeneration: Exploring Conceptualizations Of The Natural World As A Context For An Ecologically-Sensitive Curriculum, Emily A. Demoor
Soils Of Regeneration: Exploring Conceptualizations Of The Natural World As A Context For An Ecologically-Sensitive Curriculum, Emily A. Demoor
LSU Doctoral Dissertations
David Orr (1994) asserts that the ecological crisis is a crisis of education. This study explores the relationship between the ecological crisis and education by examining the role that language plays in shaping perceptions of the natural world. Toward this end it analyzes narratives of science, literature and other disciplines that conceptualize the natural world as object and as subject. It evaluates how particular metaphors used in reference to the natural world enhance or impede ecological understanding and the cultivation of responsibility and stewardship and considers ways in which these conceptualizations might be used as a basis for new curriculum …
A Comparison Of Life Histories And Ecological Aspects Among Snappers (Pisces: Lutjanidae), Fernando Martinez-Andrade
A Comparison Of Life Histories And Ecological Aspects Among Snappers (Pisces: Lutjanidae), Fernando Martinez-Andrade
LSU Doctoral Dissertations
An extensive search for data on life-history and ecological variables was conducted for a representative number of the species within the family Lutjanidae. After creating different databases and standardizing all data, these variables were examined in statistical, correlation and graphic analyses. Additionally, a series of Principal Component Analyses were used to examine patterns among variables. Life-history variables included age at length zero, asymptotic length, maximum length, longevity, asymptotic weight, length at maturity, age at maturity, reproductive life span, growth rate and mortality rate. Ecological variables included latitudinal and vertical distribution, habitat selection (represented by substrate type), and spawning seasons. The …