Digital Commons Network^™

Investigation Of A Low-External-Input Sustainable Rice Production System To Identify Ecosystem Services Towards Adoption Costs And Benefits, Alexandra Gwin Firth

Theses and Dissertations

This study investigated a potentially sustainable rice production system in the Mississippi Alluvial Valley (MAV) that uses ecological principles to enhance environmental quality at the field scale. It was hypothesized annual flooding of rice fields to create waterbird habitat would benefit soil health, providing agronomic benefits to the farmer. Two sites were selected: a low-external-input-sustainable-agriculture (LEISA) system with flooded (LF) and nonlooded (LN) fields and a conventional site with flooded (CF) and nonlooded (CN) fields. Soil microbial diversity and nutrient content were quantified and compared. Camera traps were used to document bird activity for estimates of fecal matter input. Soil …

Top-Down And Bottom-Up Effects On Collembola Communities In Soil Food Webs, Jordan Kustec

Electronic Thesis and Dissertation Repository

Anthropogenic changes are causing shifts within soil food web communities, which may alter ecosystem processes such as nutrient cycling, carbon storage and decomposition. I quantified ecological stressor effects on the abundance, richness, community composition and body size of a soil-dwelling microarthropod (Collembola: Hexapoda). I quantified the effects of warming and nitrogen deposition in two separate field studies and demonstrated that warming shifts Collembola community structure and decreases community body size. I quantified the interactive effects of top-down and bottom-up forces mediated by warming as ecological stressors in Collembola communities. I found that bottom-up effects of nutrient addition did not affect …

Fall Migration And Winter Habitat Use Of Northern Saw-Whet Owls (Aegolius Acadicus) In The Ozark Highlands, Mitchell L. Pruitt

Graduate Theses and Dissertations

Studying movement ecology is important not only in understanding the distribution of a species, but in understanding the magnitude of migration through certain regions, as well as explaining regional differences in demographics. The Northern Saw-whet Owl (Aegolius acadicus) is a small, migratory forest owl found throughout much of North America. Despite being captured widely during fall migration, the species’ movement ecology is poorly understood. Exploratory studies outside the saw-whet owl’s normal range have successfully captured the species during fall migration. In the Ozark Highlands ecoregion of the central United States, their status has been considered vagrant during fall and winter. …

Where Are All Of Arkansas' Chinquapins? An Ecological Assessment Of Castanea Throughout The State, Logan Pierce Estes

Graduate Theses and Dissertations

Around the turn of the twentieth-century, the chestnut blight fungus (Cryphonectria parasitica) was accidentally introduced into North America. This strong pathogen, which specializes on trees of the genus Castanea, spread rapidly and within half a century had nearly extirpated North America’s Castanea natives from their ranges. During this catastrophe, the American chestnut (Castanea dentata) garnered much of the scientific attention, pushing the other Castanea natives – the chinquapins – to the wayside. More than a century following the spread of the blight, little research into the ecology of North America’s chinquapins had been performed, leaving these trees significantly underrepresented. The …

Behavioral Thermoregulation And Thermal Mismatches Influence Disease Dynamics In Amphibians, Erin Louise Sauer

USF Tampa Graduate Theses and Dissertations

Amphibians are currently the most threatened vertebra taxa on the planet. Hundreds of species are thought to have gone extinct while thousands more have been listed as threatened or endangered over the past few decades. Habitat loss, invasive species, climate change, and disease are all thought to have partially contributed to these declines. Two pathogens in particular, infectious viruses in the genus Ranavirus (simply referred to as ranavirus) and the fungus Batrachochytrium dendrobatidis (Bd), have been associated with global mass mortality events of amphibians. Virulent pathogens such as these tend to impose strong selective pressures on their hosts driving the …

Diets And Stable Isotope Signatures Of Yellowtail Rockfish (Sebastes Flavidus) In Central California, Jennifer Chiu

Master's Theses

Studies of fish diets can improve the understanding of trophic distributions and the predatory role of a species in an ecosystem. Identifying the spatial and temporal variability in the diets of fishes can provide useful information for stock assessments and management. Yellowtail Rockfish (Sebastes flavidus) are a commercially and recreationally important fishery species, and abundant along the central California coast, yet the most recent studies of diets occurred over 20 years ago in Oregon and Washington. To provide current information from California, I examined the food habits of Yellowtail Rockfish collected near Cordell Bank, the Farallon Islands, and Half Moon …

Impacts Of Natural And Anthropogenic Colonized Habitats On The Range Shifting Mangrove Tree Crab (Aratus Pisonii), Zachary John Cannizzo

Theses and Dissertations

Mis-matches in climate-mediated shifting rates cause the ranges of some species to become decoupled from their historic ecosystem, leading to the colonization of ecosystems they have not previously inhabited. When this occurs, the shifting species may experience suboptimal conditions which challenge its ability to persist and expand into the novel ecosystem. However, within the colonized ecosystem, shifting species may encounter artificial habitat analogues: artificial habitats that more closely resemble the species’ historic ecosystem than the surrounding habitat and which mitigate some of the negative impacts experienced elsewhere in the novel ecosystem. Despite their importance to the ecology, life history, and …

The Tallgrass Prairie Soundscape; Employing An Ecoacoustic Approach To Understand Grassland Response To Prescribed Burns And The Spatial And Temporal Patterns Of Nechrophilous Invertebrate Communities, Sarah Dodgin

Master's Theses and Capstones

Tallgrass prairies are rapidly vanishing biodiversity hotspots for native and endemic species, yet little is known regarding how spatial and temporal variation of prairie soundscapes relates to seasonal changes, disturbance patterns and biological communities. Ecoacoustics, the study of environmental sounds using passive acoustics as a non-invasive tool for investigating ecological complexity, allows for long-term data to be captured without disrupting biological communities. Two studies were carried out by employing ecoacoustic methodology to study grassland carrion food webs and to capture the phenology of a grassland soundscape following a prescribed burn. Both studies were conducted at the Nature Conservancy’s Tallgrass Prairie …

The Bioeconomics Of Shade-Grown Coffee Production Under Climate And Price Risks In Puerto Rico, Yixuan Gao

Master's Theses and Capstones

Coffee production is severely affected by global climate change. One of the important impacts comes from the increasing infestation and distribution of coffee berry borer (CBB), the most damaging coffee pest worldwide. Shade-grown coffee (SGC) systems can alleviate the impacts and increase the resilience of coffee farms by providing non-market and market ecosystem services.

From an ecological perspective, SGC systems can provide many non-market ecosystem services such as pest risk mitigation, soil water retention, soil fertility, and pollination, which are all critical factors affecting coffee yields. From a financial perspective, SGC systems can benefit farmers by increasing the prices through …

Home Range And Microhabitat Associations Of The Southern Red-Backed Vole (Myodes Gapperi) In New Hampshire Forests, Honora Tisell

Master's Theses and Capstones

Resources, such as food and shelter, are unevenly distributed across the landscape at both macro and micro scales. Home range is one measure of space use that reflects an individual’s resource requirements (e.g., microhabitat characteristics) and competition for those resources (e.g., density dependence). This study focuses on the home range of the southern red-backed vole (Myodes gapperi), comparing field methods for estimating home range and modeling the microhabitat characteristics that define the core area of the home range. Southern red-backed voles (Myodes gapperi) are common to boreal forests, most often found in coniferous or mixed deciduous stands, and in the …

Developing Spectral Metrics As Early Indicators Of Water Stress Detection At The Canopy Level, Korik Vargas

Master's Theses and Capstones

Drought has become an increasing concern over the last few years in forest ecosystems. Understanding how forests respond to drought is critical to elucidate possible drought consequences for forest ecosystem structure and function. There is growing consensus that future climates will be characterized by extreme droughts and extreme precipitation events that will fall outside the historical range to which species and ecosystems are adapted. The limited information of how Northeastern U.S. forest tree species will respond to moderate to extreme drought events have promoted an increasing need to develop monitoring techniques which help us better understand the implications of future …

Toward A Posthuman Ecology: Evolutionary Aesthetics In Transatlantic Romanticism, Kaitlin Mondello

Dissertations, Theses, and Capstone Projects

My dissertation traces the vibrant interchange between Romantic literature and science in the nineteenth century that necessitated new forms of aesthetics. I argue that Romantic writers and scientists co-created a new way of understanding nature that moved away from hierarchical anthropocentrism toward what I call “posthuman ecology.” This work explores shared scientific, literary, and philosophical sources for Erasmus and Charles Darwin, Mary and Percy Shelley, Ralph Waldo Emerson, and Emily Dickinson. I connect aesthetic innovation to ethics to ask more broadly how literature can provide an affective and effective space to represent and engage scientific discourse. I conclude that understanding …

Investigation Of Chaos In Biological Systems, Navaneeth Mohan

Electronic Thesis and Dissertation Repository

Chaos is the seemingly irregular behavior arising from a deterministic system. Chaos is observed in many real-world systems. Edward Lorenz’s seminal discovery of chaotic behavior in a weather model has prompted researchers to develop tools that distinguish chaos from non-chaotic behavior. In the first chapter of this thesis, I survey the tools for detecting chaos namely, Poincaré maps, Lyapunov exponents, surrogate data analysis, recurrence plots and correlation integral plots. In chapter two, I investigate blood pressure fluctuations for chaotic signatures. Though my analysis reveals interesting evidence in support of chaos, the utility such an analysis lies in a different direction …

An Ecology Not Taking-Place: Analysing Ecocriticism's Move From Place And Space To Spacing And Displacement Through Derrida, Morton, And Haraway, Andrew Case

Electronic Thesis and Dissertation Repository

Deconstructive readings of place-space dichotomies in ecological thinking reveal not only a repetition of the subject-object divide examined by Derrida and others, but also a spacing in between these categories. Morton and DiCaglio establish the importance of the in-between to ecological thinking and writing, and they demonstrate how literary and physical irony can reveal this spacing to the reader through an experience of displacement. By choosing to reject norms and instead linger in the spacing, individuals can enact a non-lieu-tenance that radically undermines sovereign systems, defers place, and opens up the possibility of new kinds of intimacy and community. By …

The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley

Electronic Theses and Dissertations

The Cave Salamander, Eurycea lucifuga (Rafinesque, 1822), is a little-known species, yet a common inhabitant of caves in the eastern United States. Salamanders are often important components of ecological communities and ecosystems, influencing critical processes such as nutrient cycling and community composition through their predation on invertebrates. Cave-dwelling salamanders such as E. lucifuga may thus appreciably influence the relatively simple ecosystems and communities of caves. Any such influence may be particularly important because these habitats and the organisms that reside in them are often of conservation concern. I used non-invasive methods to study the demographics, movements, and habitat selection of …

Leonardo Boff’S Social-Environmental Ecology Exposition, Analysis, And Appropriation For Lutheran Theology, Alan Furst

Master of Art Theology Thesis

Furst, Alan Diego. “Leonardo Boff’s Social-Environmental Ecology: Exposition, Analysis, and Appropriation for Lutheran Theology.” MA Thesis, Concordia Seminary, 2018. 107pp.

Ecological issues throughout the world present an urgent need for a deepened theological approach to the doctrine of creation. In fact, recent studies have shown that such issues point to a more serious problem with the entire system at work shaping social relations today. This situation calls Christian theologians to rethink the doctrine of creation in light of ecological issues. This includes Lutheran theologians, who still need to address the current situation involving ecological issues and to offer reflections and …

Woodpeckers In The City: Habitat Use And Minimum Area Requirements Of Woodpeckers In Urban Parks And Natural Areas In Portland, Oregon, Adam Baz

Dissertations and Theses

Urbanization has contributed to the fragmentation and alteration of natural habitats around the globe, and is rapidly increasing. In this context, forested parks play a critical role for many species by providing patches of usable habitat within the urban matrix. Such patches may be particularly valuable to forest-specialists like woodpeckers (Picidae). Yet many woodpeckers require large forest patches, which are limited in fragmented landscapes. Despite their recognized value as ecosystem engineers and keystone species, almost no research exists on woodpecker ecology or space-use in urban settings. What habitat components influence woodpecker abundance and what are their functional minimum area requirements …

The Effects Of Gopher Tortoise (Gopherus Polyphemus) Herbivory On Plant Community Composition And Seed Germination, And The Effects Of Gut Passage On The Germinability Of Seeds: A Meta-Analysis, Jason C. Richardson

USF Tampa Graduate Theses and Dissertations

Herbivory produces direct and indirect effects on plants and at different spatial scales will have varied consequences. Consumption of plants by vertebrate grazers may affect the plants on an organismal level through direct mortality, on a community level by changing species composition or by altering the rate of succession, and even at a whole ecosystem level by altering nutrient cycles.

The majority of the scientific literature has focused extensively on herbivory by mammals and birds. With regard to mammals, studies have shown how folivory affects individual plants, plant populations, and communities of plants.

Mammals, as well as birds, also ingest …

Improving Habitat Restoration For Native Pollinators In San Francisco, Tyrha Delger

Master's Projects and Capstones

Pollinators are responsible for 67 to 98% of flowering plant reproduction while 90% of all plants are flowering. This does not change in urban environments and focusing on habitat restoration in cities is important for the conservation of species. This paper focuses on urban habitat restoration in San Francisco for three species: Callophrys viridis, Icaricia icarioides missionensis, and Bombus californicus. These three species are all native of San Francisco and are all threatened by loss of habitat within the city. The problems these species face in urban environments, as well as the successes and failures of other habitat conservation programs, …

Managing Riparian Succession And Stabilizing Native Plant Assemblages In The Middle Rio Grande State Park, Roman M. Lopez

Architecture and Planning ETDs

Anthropogenic alterations of hydro geomorphological conditions of the Rio Grande River have changed the processes that have created the mosaic of riparian habitats valuable for ecosystem functioning, wildlife, and enjoyment by residents. These changes have created conditions that have increased the frequency of historically unprecedented disturbances such as fire and aggressive invasion of exotic species. Restoration activities and planning efforts have begun to reverse these effects, yet large areas of the Middle Rio Grande State Park, commonly called the Bosque, are still being affected by ecosystem changes. Studies of the Rio Grande and other Riparian corridors suggest that lack of …

Making Sounds, Patrick Costello

Theses and Dissertations

Using collaboration and performance as tools, I situate my personal story, my body, and my skills and interests within a contemporary landscape that is intersectional, full of partialities, and rooted in evolving ecologies.

Comparison Of Otus And Asvs In 73 Bird Species From Equatorial Guinea, Darien Capunitan

Master's Theses

As scientists discover more information about the communities of bacteria that live on and inside hosts, "the microbiome", a new avenue for understanding the health of humans and animals has opened. There are many analysis pipelines for microbiome data processing, and choice of analytical tools can affect the biological results of the analysis. The current analysis climate does not point toward a single most effective protocol, which hinders comparisons across studies. An important step in microbiome data processing is the assignment of reads into groups of similar organisms. The traditional unit for grouping organisms is the species; however resolving sequences …

The Trophic And Spatial Ecology Of The Southern Flying Squirrel (Glaucomys Volans) And Non-Lethal Deterrent Methods, Robert Timothy Meyer

Theses and Dissertations

Southern flying squirrels (SFS; Glaucomys volans) are known kleptoparasites on the endangered red-cockaded woodpecker’s (RCW; Picoides borealis) cavities and cost land managers time and money to control and the ecology of SFS in habitats managed for RCWs is poorly understood. This study is designed to obtain a better understanding of the general ecology of SFSs surrounding RCW habitat and provide possible non-lethal deterrent methods to prevent harmful interactions between SFSs and RCWs. Spatially-explicit capture-recapture showed generally higher SFS densities and habitat associations outside of RCW cluster partitions. Stable isotope analysis of SFS diets across Mississippi and Alabama revealed a narrow …

Emulated Ecology, Erik Graves

Bachelor of Architecture Theses - 5th Year

Natural versus built environment. Nature versus man made. Organic versus inorganic. These are arguments that have been stated and debated since the early architectural times of Vitruvius and are still prevalent even in today’s popular practice. As a whole architecture has moved towards a more green direction with the introduction of programs such as LEED and Architecture 2030. We have become more and more strict on the way we grade and evaluate the sustainability of a project, not just in the energy used and stored in the construction and operation of a building, but we have even begun to look …

Modified Landscapes, Esther Nooner

Graduate Theses and Dissertations

Modified Landscapes is a body of work that reflects serious thought regarding Nature and its future. My personal experience and beliefs are at the core of why I believe this subject to be of great importance and why it will sustain many artists’ investigations for the time to come. The influences that informed this process are explored through experiences I had traveling, reading and exploring the photograph as a material object. The manipulation of the photograph is meant to question the beautiful, untouched scene and break the Romantic gaze that is historically tied to representations of Nature and insist upon …

Impacts And Management Of Foliar Pathogens Of Eastern White Pine (Pinus Strobus) In The Northeastern United States, Cameron Ducayet Mcintire

Doctoral Dissertations

White Pine Needle Damage (WPND) is a complex of foliar fungal pathogens currently impacting forests in the Northeastern US. Since ca. 2009, chlorosis and defoliation caused by WPND has been observed in stands of eastern white pine (Pinus strobus L) throughout the region. A changing climate, notably warmer temperatures and higher than average spring precipitation in the region are thought to be exacerbating the establishment and spread of these native pathogens. The goals of this research are to enhance the understanding of the timing and magnitude of WPND-induced defoliations across infected stands, assess the physiological response of trees affected by …

Wild Bee Declines And Changes In Plant-Pollinator Networks Over 125 Years Revealed Through Museum Collections, Minna Mathiasson

Master's Theses and Capstones

Though recent literature highlights widespread bee declines, detailed information on local communities, plant-pollinator network interactions and individual species remains distressingly scarce. In order to accurately direct conservation initiatives and to evaluate the status of wild bees and their host plants, long-term data on these populations is critical. Examining pollinator communities across regional scales highlights small-scale changes that go undetected in larger investigations. In light of unknown effects of introduced species and cumulative range expansions of exotic taxa, monitoring wild communities closely and extensively over time is becoming increasingly important. The focus of this thesis is to investigate a regional wild …

The Photosynthesis-Foliar Nitrogen Relationship In Deciduous And Evergreen Forests In New Hampshire, Conor Madison

Master's Theses and Capstones

Biomass production in forests is a key process in the global carbon (C) cycle that is strongly linked to photosynthesis and related leaf traits. Spatially, relationships among leaf traits can vary as a function of climate, soils and species composition. As modeling approaches to estimate C gain improve, the need to understand variability in leaf traits becomes increasingly important. Here, we characterized the relationship between photosynthetic capacity (Amax), foliar nitrogen and leaf mass per area (LMA) within and across species in northern hardwood and evergreen stands of the White Mountain National Forest in New Hampshire, a region that has been …

Seabird Distribution And Oil & Gas Potential Along The Northern Sea Route, Russia: An Arctic Marine Conservation Case Study, Meghan Kelly

International Development, Community and Environment (IDCE)

Seabirds are indicator species for the marine environment. Their populations are simultaneously affected by access to food resources and anthropogenic pressures including direct disturbance and habitat degradation associated with industrial development (Parsons et al. 2007). Therefore, using seabird distribution as a policy-relevant indicator for the Arctic marine environment supports an ecosystem based management approach aimed at protecting sensitive habitats from increased offshore oil and gas development.

This research identifies seabird habitat in the Russian Arctic utilizing in situ seabird observations from the Northern Sea Route to create a species distribution model. The spatial location of these areas will be compared …

Persistence Of Cultural Heritage In A Multicultural Context: Examining Factors That Shaped Voting Preferences In The 2016 Election, Anna M. Schwartz

Dissertations, Theses, and Capstone Projects

The prevailing discourse about the myth of the “melting pot” of American culture implies that heritage cultures are eliminated in favor of a homogenous “American” norm. However, this myth belies the persistence of our cultural heritage in forming our attitudes, morals, and habitual patterns of thought, each of which shape how we participate in our democracy through voting. By contextualizing voting predictors such as authoritarianism, social dominance, and sexism in developmental and ecological theories, this dissertation shows how they are shaped by culture and transmitted through consumption of media and interaction with members of one’s community and family. In an …