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Evaluating The Ecological Status Of The Introduced Nile Monitor (Varanus Niloticus) In Florida: Forecasting Presence And Population Expansion Using Computational Geographic Information Systems, Noah G. Cohen

HCNSO Student Theses and Dissertations

The Nile monitor (Varanus niloticus) is a large, carnivorous lizard that has become a notorious invasive species in Florida, USA. Initially released in the 1980s from the pet trade, the species has since established at least three breeding populations and spread throughout much of southern Florida. While current control efforts have failed to eradicate V. niloticus, it is important to attain a better understanding of its invasive dynamics to guide and inform better control strategies. In this study, available georeferenced records of V. niloticus in Florida were compiled and linked to a habitat classification map to evaluate ecotype preferences. Factored …

The Relationship Between Positive Behavior Interventions And Supports And School Climate/Culture In Elementary Schools, Zaheerah Nadiyah El-Amin

Doctoral Dissertations

Based on the Individuals with Disabilities Education Act (IDEA) mandates, weakened climate/culture, decreased academic scores, and endangered job security, the implementation of a successful behavioral intervention program within the school setting was a necessity (Homer & Sugai, 2000). Quantitative data were obtained from two assessment tools, the School-wide Evaluation Tool (SET) and the School Climate Assessment Instrument (SCAI). To determine the levels of implementation of Positive Behavior Interventions and Supports (PBIS), and if there were significant differences in the levels of the participating schools' climate and culture, the following research questions were answered: (a) What is the level of implementation …

Depositional And Environmental Controls On Oxygen And Carbon Isotope Compositions Of Late Pleistocene To Mid-Holocene Shelly Fauna From The Huron Basin, Ontario, Canada, Jane Wilson

Electronic Thesis and Dissertation Repository

The δ¹⁸O and δ¹³C of aragonitic mollusc shells were analyzed from nine sites in the Huron Basin, Ontario, Canada. These sites represent three lake phases spanning the Late Pleistocene to the mid-Holocene (Algonquin, Transitional, and Nipissing) and three depositional environments (fluvial, estuarine, and lacustrine). Depositional environment controls mollusc δ¹⁸O more strongly than climate. The source of carbon and climate control the δ¹³C of the shelly fauna. Shells from fluvial sites are most depleted of ¹⁸O and exhibit the greatest antipathetic δ¹³C-δ¹⁸O covariation. This reflects the dynamic nature of this system. Lacustrine sites have …

By Degree: A History Of Heat In The Subtropical American South, Jason Hauser

Theses and Dissertations

Heat has a history, both because temperatures changed and the way humans understand and experience those temperatures changed. This dissertation excavates that history by examining how southern heat—heat considered distinct to the subtropical American South—affected the social, economic, and political development of the United States. This dissertation argues that southern heat proved consequential for the nation as both a physical force and human construct, and that only by keeping the materiality of relatively high temperatures in conversation with the idea of heat does a full history of southern heat emerge. By looking at how humans interacted with southern heat, both …

Ecological Niche Modeling Of The Genus Papio, Amanda J. Fuchs

Theses and Dissertations

Ecological niche modeling investigates how climatic variables have influenced taxonomic diversity in Papio. Models performed well suggesting climatic variables influence the distribution of baboon species. Niche overlap among all possible pairs of taxa determined that species exhibited significantly different niches. The results of these models support a parapatric speciation scenario.

Climatic Controls On The Porewater Chemistry Of Mid-Continental Wetlands, Zeno Francis Levy

Dissertations - ALL

Wetlands develop where climate and physiography conspire to maintain saturated soils at the land surface, support diverse plant and animal communities, and serve as globally important sinks for atmospheric carbon. The chemistry of wetland porewaters impacts near-surface biological communities and subsurface biogeochemical processes that influence carbon cycling in the environment. Wetland porewater chemistry is a dynamic byproduct of complex hydrogeological processes that cause meteoric waters to enter groundwater systems (recharge) or groundwater to flow to the land surface (discharge). Changes in climate can alter subsurface hydraulic gradients that determine the recharge and discharge functions of wetlands, which in turn control …

A Good Kiwi Isn't Acidic: How Ocean Acidification Is Affecting The New Zealand Economy, Lily G. Hurley

Student Theses 2015-Present

In a country that houses a mere 4 million people, it is no wonder that agriculture has become the main facet of New Zealand’s economy. However, while the sheep and produce have flourished from land protection laws, marine life has struggled in recent years due to an increase in oceanic carbon levels. In an area of the Pacific that is so rich in coral reefs, Great White breeding areas, and a plethora of fish species, any upset of the natural preexisting chemical balance has a tangible impact. New Zealand is dealing with a crisis with huge economic and ecological ramifications. …

Adaptive Capacity And Governance Effectiveness Of Wetfish Fisheries, Stacy Elizabeth Aguilera

Open Access Dissertations

Fisheries contribute a wide variety of ecosystem services, from food provisioning to shaping community identity to bolstering local economies. The sustainability of these benefits is under threat due to global and local stressors, including climate change, rising demand for animal protein, and habitat destruction. The dynamic climate, governance, and market drivers influencing fisheries present social and ecological challenges and opportunities that form the focus of this dissertation. Examining the adaptive capacity of a fishery offers insight into diverse aspects of the system that influence outcomes, such as trends in landings, social stability, and habitat condition. Additionally, academic theories, including Ostrom’s …

Environmental And Climatic Constraints On Large-Scale Camelina Production In Eastern Arkansas, Benjamin Robert Tracy

Graduate Theses and Dissertations

Camelina sativa is a cold weather crop that is typically grown in semi-arid environments in the Western United States, usually as a spring crop, but sometimes during the winter. Research analyzing climate data and soil hydrology is important to better understand the environmental and terrain conditions necessary for Camelina farming wherever it is proposed for large-scale production. This study focused on various conditions and constraints pertaining to the potential for Camelina as a crop biofuel in Eastern Arkansas. Due to interest in the economic potential of crop biofuels in this area, and in particular the low input costs for Camelina, …

"There Is No Planet B": Frame Disputes Within The Environmental Movement Over Geoengineering, David Russell Zeller Jr.

USF Tampa Graduate Theses and Dissertations

This dissertation examines frame disputes within the environmental movement over geoengineering proposals. Among other core framing tasks, social movement organizations must evaluate solutions and strategies for the social problems they seek to address. These framings are frequently disputed by those within the movement. Recent controversies regarding a set of climate intervention proposals commonly known as geoengineering offer the opportunity to document the ongoing construction of competing visions of environmental sustainability. The nascent quality of these proposals generate dissonant framings—episodes where organizations within the environmental movement exhibit disagreement about one or more core framing tasks—a situation Goffman referred to as a …

Comparative Biogeography Of North American Pika Parasites: Unraveling A History Driven By Climate Change, Heather M. Toman

All NMU Master's Theses

Parasites are an understudied group that can provide important information on ecosystem dynamics and climate change as well as host biogeographic history. I performed a comparative biogeographic study on two endoparasitic helminth lineages associated with pikas (Ochotona) -the tapeworm genus Schizorchis and the pinworm subgenus Labiostomum (Eugenuris). Colonization history across Beringia was assessed using analyses of historical range estimation and tests for simultaneous divergence. Analysis results allow me reject the hypothesis that these parasites colonized the Nearctic during a single glacial cycle, as evidenced by multiple Nearctic and Palearctic lineage pairs that did not diverge simultaneously. This …

A Multi-Proxy Stalagmite Reconstruction Of The Climate Of Southwestern North America From The Middle To Late Holocene, Christine Allen

Earth and Planetary Sciences ETDs

The seasonal balance of moisture has a significant effect on natural ecosystems and culture in southwestern North America (SWNA), and it thus is necessary to understand the cause of this moisture variability in order to better predict the scope of potential future changes. Studies of modern SWNA climate indicate that most of the annual moisture at this site comes from monsoonal summer precipitation and a lesser amount of Pacific winter moisture. The climate of the Holocene is of particular interest for constraining natural variability of interglacial climates prior to any anthropogenic influence. An overall transition to a wetter Late Holocene …

An Epidemiological Study Of West Nile Virus In Maricopa County, Arizona, Shawna Bronte

Public Health Theses

Introduction: Vector-borne infectious diseases represent a major public health problem in both developing and developed nations. In particular, West Nile Virus (WNV), a mosquito-borne disease that can lead to severe disease and death in humans, caused over 2,100 reported cases in the United States last year (CDC, 2016). In Maricopa County, Arizona WNV has caused 474 reported cases during the last five years, with a case-fatality rate at 7.8%.

Aim: To examine the association between weather patterns and incidence of WNV in Maricopa County, AZ from 2007 to 2013.

Methods: We analyzed weekly data on climatological variables and WNV incidence …

Patterns And Drivers Of Carbon Fluxes In Temperate Forests, Andrew Ouimette

Doctoral Dissertations

Despite decades of carbon cycling research in terrestrial ecosystems, a complex suite of biotic and abiotic interactions make a complete understanding of the natural carbon cycle elusive. This thesis aims to advance our understanding of the carbon cycle, and stems from several ongoing projects aimed at quantifying carbon dynamics in forest ecosystems across a range of scales, with a specific effort to include both above and belowground components of forest ecosystems. I begin with a project using detailed chemical measurements on specific segments of root systems from two different tree species, in order to help refine methods that quantify the …

Historical Precipitation Trends And Future Precipitation Projections Using A Stochastic Weather Generator In The Northeastern United States, Andrew Louis Goldman

Master's Theses and Capstones

According to the 2014 National Climate Assessment, annual rainfall has increased by approximately 10% from 1895 to 2011, and extreme precipitation events (the top 1% of all storms) have increased 70% since 1958 in the Northeast United States [Melillo et al., 2014]. These precipitation changes could have substantial impacts on the performance of bridges, stormwater drainage, pavement, water supply systems, and numerous other infrastructure projects. This study examines historical changes in Northeast rainfall and develops a computer model to simulate future precipitation. Historical precipitation trends were calculated for rainfall duration, depth, intensity and time between storms for 20 weather stations …

Environmental Migration From Egypt And Morocco: A Comparative Study, Mahir Ali Sheikh

Senior Projects Spring 2017

As economies continue to industrialize and grow, human activity and general changes in weather patterns have had an adverse effect on the global climate. Global temperature continues to rise creating changes in the climate of many different areas of the world, increasing the intensity of sudden and slow onset disasters. Less developed countries in the Middle East and North Africa particularly Egypt and Morocco are two economies that are negatively affected by certain dimensions of climate change. These dimensions of climate change have direct implications on internal and international migration patterns of these countries. Both countries rely on agriculture as …

Influence Of Psychological Empowerment, Leadership, And Climate On Safety Outcomes, Christine Healy

Walden Dissertations and Doctoral Studies

Research has demonstrated that safety outcomes are impacted by workplace risk factors, but also supervisory practices and employee actions. An area that has not been explored is the impact of employee cognitions on safety outcomes defined as work-related injuries. Based on the conceptual framework of psychological empowerment (PE), the purpose of this study was to examine the relationship of employee cognitions as measured by PE as related to leadership and safety climate and the occurrence of work-related injury. The research examined the mediating effect of (PE) on the factors of leadership and safety climate and their relationship to work-related injury. …

Post-Wildfire Black Carbon Deposition On The Snowpack In The Cascade Range, Washington State: Temporal And Spatial Variability With Implications For Accelerated Melt, Ted Uecker

All Master's Theses

Wildfires in the seasonal snow zone affect both snow accumulation and ablation patterns by decreasing forest canopy and depositing light absorbing impurities (LAI) on the snowpack. LAI such as black carbon (BC), burned woody debris, and dust reduce snow albedo (reflectance), accelerate melt, and affect the timing and availability of water resources. Charred trees in post-wildfire forests provide a significant source of BC that is deposited on the snowpack for years following a wildfire, and this effect varies with burn conditions and forest structure. Snow samples were gathered from five sites of varying burn age (0.7, 2.7, 3.8, and 9.8 …

Understanding Patterns And Drivers Of Alaskan Fire-Regime Variability Across Spatial And Temporal Scales, Tyler J. Hoecker

Graduate Student Theses, Dissertations, & Professional Papers

Boreal forest and tundra ecosystems are globally important because the mobilization of large carbon stocks, and changes in energy balance could act as positive feedbacks to ongoing climate warming. In Alaska, wildfire is a key driver of ecosystem structure and function, and therefore fire strongly determines the feedbacks between high-latitude ecosystems and the larger Earth system. The paleoecological record from Alaska reveals the sensitivity of fire regimes to climatic and vegetation change over centennial to millennial time scales, highlighting increased burning with warming and/or increased landscape flammability associated with large-scale vegetation changes. This thesis focuses on two studies aimed at …

Impacts Of Internal Variability On Climate Trends In Large Ensemble Simulations By Two Climate Models, Christine Bloecker

Legacy Theses & Dissertations (2009 - 2024)

Internal climate variability (ICV) can influence trends in observations and model simulations over periods spanning decades, making it difficult to quantify the response of the climate system to external forcing. We analyze two large ensembles of climate simulations from 1950-2100 by two fully coupled climate models, namely the CanESM2 and CESM1, to quantify the effects of ICV on apparent trends in annual surface air temperature (T) and precipitation (P) over different time periods and regions. In comparison with observations, the CanESM2 overestimates the global T and P trends during 1979-2014 while they fall within the ICV-induced range of the CESM1. …

Influence Of Volcanic Eruptions On Tropical Hydroclimate During The Last Millennium, Christopher Colose

Legacy Theses & Dissertations (2009 - 2024)

Volcanic eruptions exert the most important radiative forcing on Earth’s climate during the pre-industrial interval of the last millennium. In this thesis, I investigate the role of volcanic eruptions in altering tropical climate, including temperature and rainfall. I primarily use forced transient simulations of the last millennium as a tool to explore how explosive volcanic events project onto the hydrologic cycle, as well as the imprint of water isotopologues (H216O, H218O) associated with rainfall. Attention is given to the South American continent specifically (in chapter 2), and to the entire tropics (in chapter 3).

The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry

Cal Poly Humboldt theses and projects

Many amphibian species are in decline due to habitat loss and changing climates. Understanding how habitat characteristics and climate influence vital rates, and if they act in concert or in opposition can inform management decisions. This study investigated the potential interaction of canopy cover and climate on early stage vital rates of northern red-legged frogs. Demographic data were collected from sample populations in experimental canopy cover treatments across a latitudinal distribution. Rearing cages were used to estimate hatch success, and mark-recapture surveys to estimate tadpole survival. Ambient air temperature was used as an index of climate because it is easily …

Impacts Of Enso On Tornado Frequency, Intensity, And Geography Across The Eastern United States, Coryn Ann Collins

LSU Master's Theses

Tornadoes are a reoccurring severe weather hazard, with the highest rates globally occurring in the central United States. Despite their high frequency in the U.S., the scientific community’s disagreement of tornado activity during varying phases and intensities of the El Niño Southern Oscillation (ENSO) justifies a need for further research. In this study, tornado events from 1950 to 2014 in the U.S. east of the Rocky Mountains were investigated for seven phases of ENSO: strong, moderate, and weak El Niño/La Niña and the neutral phase. A seasonal Niño 3.4 index was used as the definition of ENSO. ENSO influences on …

A Palynostratigraphic Investigation Of Holocene Coastal Texas Bays: Implications For Future Coastal Change, Shannon Marie Ferguson

LSU Doctoral Dissertations

Although the Gulf of Mexico is one of the most studied basins in the world, a majority of the focus has been driven by petroleum exploration and/or on seismic and sedimentological facies models. Rarely has the intent of previous studies been to characterize the Holocene climatic record of coastal Texas. Of those studies that discuss Holocene vegetation change, the majority focus on the Mississippi River Delta, the Edwards Plateau or central Florida, leaving an absence of insight to western Gulf of Mexico climate changes. The Texas coastline stretches 595 km across almost 4° of latitude and the strong northwestern precipitation …