Digital Commons Network^™

Bias Correction And Downscaling Of Climate Model Outputs Required For Impact Assessments Of Climate Change In The U.S. Northeast, Kazi F. Ahmed

Master's Theses

Global Climate Models (GCMs) are the typical sources of future climate data required for impact assessments of climate change. However, GCM outputs are related to model-related uncertainties and involve a great deal of biases. Bias correction of model outputs is, therefore, necessary before their use in impact studies. The coarse resolution of GCM simulations is another hindrance to their direct use in fine-scale impact analysis of climate change. Although downscaling of GCM outputs can be performed by dynamical downscaling using Regional Climate Models (RCMs), it requires large computational capacity. When daily climate data from multiple GCMs are required to be …

Variability Of Sediment Nutrients And Benthic Macro-Invertebrates In Recreational Fishing Ponds, Tyler James Stubbs

Theses and Dissertations

The overall objective of this study was to identify trends of sediment nutrients and benthic macro-invertebrates in recreational fishing ponds. The Ekman dredge and the Yabby pump, also were compared for benthic macro-invertebrate sampling effectiveness. Large ranges in the coefficient of variation for Pw (52 – 123.9), C:N (13.4 – 124), density (61.5 – 98.5), and diversity (67 – 142) indicated significant spatial variability within and among ponds. Invertebrate familial diversity was the only variable that did not show any significant temporal variation (H = 4.31, P = 0.230). Results from the gear comparison indicated no differences between the Ekman …

Stable Isotope Diet Reconstruction Of Feral Horses (Equus Caballas) On The Sheldon National Wildlife Refuge, Nevada, Usa, Megan Kathleen Nordquist

Theses and Dissertations

Feral horse management has become a subject of significant controversy in the United States. This is because of differing opinions and minimal recent empirical data on feral horses. In recent years, numbers of feral horses have increased due to governmental horse removal restrictions (specifically the Wild Horse and Burro act of 1971). With increasing numbers of feral horses on rangelands, land managers are challenged with identifying the appropriate course of action for satisfying groups with differing opinions. The purpose of this study is to characterize diet consumption through the use of stable isotope dietary analysis (δ15N and δ13C). We did …

Constructing Spatial Weight Matrix Using Local Spatial Statistics And Its Applications, Weiming Yu

Theses and Dissertations

In this study, we extend the spatial weight matrix defined by Getis and Aldstadt (2004) to a more general case. The modified spatial weight matrix performs better than the original spatial weight matrix since the modified spatial weight matrix adjusts weights of observations based on the distance from other observations. Both the simulation study and the application to the ecological process of invasion of non-native invasive plants (NNIPs) provide evidences for the better performance of the modified spatial weight matrix. We also develop procedures that can be used to quantify the invasion stages of NNIPs. The resultant map of invasion …

Geographic Disparities Associated With Stroke And Myocardial Infarction In East Tennessee, Ashley Pedigo Golden

Doctoral Dissertations

Stroke and myocardial infarction (MI) are serious conditions whose burdens vary by socio-demographic and geographic factors. Although several studies have investigated and identified disparities in burdens of these conditions at the county and state levels, little is known regarding their geographic epidemiology at the neighborhood level. Both conditions require emergency treatments and therefore timely geographic accessibility to appropriate care is critical. Investigation of disparities in geographic accessibility to stroke and MI care and the role of Emergency Medical Services (EMS) in reducing treatment delays are vital in improving health outcomes. Therefore, the objectives of this work were to: (i) classify …

Multiple Responses By Cerulean Warblers To Experimental Forest Disturbance In The Appalachian Mountains, Than James Boves

Doctoral Dissertations

The Cerulean Warbler (Setophaga cerulea) is a mature forest obligate and one of the fastest declining songbird species in the United States. This decline may be related to a lack of disturbance within contemporary forests; however, the consequences of disturbance on the species have not been rigorously evaluated. Thus, we assessed multiple responses by Cerulean Warblers to a range of experimental forest disturbances across the core of their breeding range in the Appalachian Mountains. We quantified individual and population responses to these manipulations, and assessed the potential consequences of disturbance on the sexual signaling system. Male ceruleans were …

The Economics Of Partial Artemia Replacement Using Two Commercially Available Feeds In The Diets Of Litopenaeus Vannamei From Z3/M1 – Pl10, Monique A. Giguere

Open Access Theses

The purpose of this study was twofold: 1) to identify commercially available feeds that could serve as suitable replacements for newly hatched Artemia in the diets of L. vannamei from Z3/M1 to PL10 without significantly affecting survival, final length and weight, and quality of the larvae and 2) to identify an ideal substitution rate between live Artemia and a replacement feed that maximizes feed and labor costs savings, survival, and PL quality. In Experiment 1, two commercially available Artemia replacement feeds, Zeigler EZ Artemia and Bernaqua Vitellus, were administered according to manufacturer’s guidelines in order to identify which feed served …

The Association Between Reading Comprehension And Prerequisite Skills For Children In Poverty, Hyo Jin Yoon

Theses and Dissertations (ETD)

The purpose of this study was to investigate the relationship between reading comprehension and the prerequisite skills typically assessed by a school based speech pathologist with a focus on children raised in poverty. Based upon previous studies, three hypotheses were developed. First, children from low socioeconomic status (SES) backgrounds would not perform as well as children from the standardization sample on norm referenced language tests although the language tests would predict reading comprehension. Second, decoding would not be as good a predictor of reading comprehension for children from low SES backgrounds as it is in typically developing children from middle …

The Impact Of Ambrosia Trifida (Giant Ragweed) On Native Prairie Species In An Early Prairie Restoration Project, Krisztian Megyeri

Senior Honors Theses

As the ecological importance of prairies is becoming more recognized, the number of prairie restoration projects is increasing worldwide. One of the major challenges in restoring any disturbed ecosystem is the successful establishment of native species at the expensive of invasive species. While some weedy species are gradually replaced as other, more desired, species become established, there are invasive species that, due to their level of dominance, may out-compete native species indefinitely. The objectives of this study were 1) to quantify the impact of Ambrosia trifida (giant ragweed) on the plant community of a newsly established prairie, 2) to assess …

Using Gis To Determine The Influence Of Wetlands On Cayuga Iroquois Settlement Location Strategies, David J. Birnbaum

HIM 1990-2015

The archaeological record of the Iroquois supports that settlements were regularly relocated during the protohistoric period (1500-1650 A.D.). With the use of Geographic Information Systems (GIS) computer software, archaeologists may analyze variables potentially resulting in or influencing the movement of settlements. Through the use of spatial analysis, I argue that Cayuga Iroquois settlement locations were influenced by the environmental characteristics of their surrounding landscape. Specifically, wetlands are believed to have influenced settlement location choices in central New York state. This study examines the spatial relationships between wetland habitats and protohistoric period Cayuga Iroquois settlements where swidden maize agriculture comprised most …

A Method For Determining The Appropriate Spatial Resolution To Detect Ligustrum Sinense In Shelby Farms Park Using Worldview-2 Multi-Spectral Satellite Imagery., Rodney Quarles

Electronic Theses and Dissertations

The purpose of this thesis is to determine the appropriate scale to detect Chinese Privet (Ligustrum sinense Lour.), an invasive plant species in Shelby Farms Park. To test predictions that accuracy of detection of Chinese Privet varies with the spatial resolution of WorldView-2 satellite imagery. Supervised maximum likelihood classifications are performed upon WorldView-2, 8-band multispectral image mosaics at 2, 4, 6, and 8 meter pixel resolutions. The appropriate scale for detection was selected by performing accuracy assessments of selected land use classes, which were shown to be the least spectrally separable from Chinese Privet, using confusion matrices to report user’s …

Influence Of Timing Of Prescribed Burn On Native-Warm Season Grass Forage Quality In Tennessee, Amanda L. Mathenia

Masters Theses

Native warm-season grass stands have the prospective to provide nutritious summer forage in grazing systems. The study examined the influence of timing of prescribed burn on native warm-season grass stands in Tennessee. The purpose of the study was to determine the nutritional quality of forage as it relates to the timing of prescribed burns on native warm-season grass stands in Tennessee. The prescribed burns were conducted in March, April, May, and September. Forage samples were collected at Ames Plantation, West Tennessee Research and Education Center, Bridgestone/Firestone Wildlife Management Area, and Yuchi Wildlife Management Area. These samples were then analyzed for …

Gis Assisted Problem Analysis Of Trail Erosion In Monongahela National Forest, Steven J. Storck

Graduate Theses, Dissertations, and Problem Reports

This research investigates the frequency and patterns of trail erosion on purposefully selected natural surface trails in Monongahela National Forest. Trail erosion is considered a non-self-limiting process which degrades trail beds making them unattractive, difficult to travel on, and has the potential to impact local streams with the introduction of silt. Recreation ecology research delineates factors which influence the rate of erosion on a trail into three broad categories: recreational use, environmental conditions, and managerial actions. This study tests the relationship of variables from each of these categories to the local patterns of erosion. Three sampling strategies are used to …

Effects Of Canopy And Cultural Treatments On Fine Fuel Production, Fire Behavior, And Short-Term Fire Effects In Loblolly Pine (>I/I< L.) Stands Being Restored To Longleaf Pine (>I/I< Mill.), Carsyn Tennant

All Theses

Across the southeastern United States, anthropogenic factors such as land conversion and fire suppression have resulted in the prevalence of loblolly pine in areas historically occupied by longleaf pine. Compared to longleaf pine forests, loblolly stands often contain a substantial broad-leaved midstory and lack the ground layer that contributes fuels essential for the frequent, low intensity surface fire regime necessary to sustain the longleaf ecosystem. Currently, there is considerable interest in restoring longleaf pine habitats to areas occupied by loblolly pine. The retention of mature canopy trees is often necessary to maintain ecosystem function, to preserve habitat features, and to …

Earthworms Of Arkansas And Contributions Of Earthworm Evolutionary Origin And Ecological Group To Nitrogen Cycling In A Model Soil And Tall Fescue System, Peter John Tomlinson

Graduate Theses and Dissertations

Evolutionary origin and ecological niche may impact how earthworm species affect N cycling. Tall fescue (Lolium arundinaceum (Schreb) S. J. Darbysh) infection with the toxic endophyte Neotyphodium coenophialum Glenn, Bacon & Hanlin (E+) may influence earthworm communities in soil compared to non-toxic endophyte (NE+) infected tall fescue. Conversely, different earthworms may contribute different amounts of N to E+ vs. NE+ tall fescue. A field survey was conducted from January 2007 to January 2008 to determine the impact of E+ and NE+ tall fescue, planting date, and seasonal variables, e.g. soil temperature and moisture, on earthworm species, abundances, and population …

Composition And Ecophysiological Proficiency Of Tidal Freshwater Forested Wetlands: Investigating Basin, Landscape, And Microtopographic Scales, Jamie Duberstein

All Dissertations

A hierarchical approach to forest community assessment was conducted by first focusing on landscape associations to edaphic factors among major tidal freshwater forested wetland basins in the Southeast. Four general tree communities exist along coastal rivers in the southeastern United States, based on the most prominent species in each: Water Tupelo, Swamp Tupelo, Dwarf Palmetto, and Cabbage Palm. Microhabitat usage and preference by trees were then examined, both across all species and within species, as related to such factors as coast, presence on rivers with dams, tree community assemblage, relative distance from the river, specific river basin, and microsite availability. …

Exploration Of Stream Habitat Spatial Modeling; Using Geographically Weighted Regression, Ordinary Least Squares Regression, And Natural Neighbor Interpolation To Model Depth, Flow, And Benthic Substrate In Streams, Kenneth R. Sheehan

Graduate Theses, Dissertations, and Problem Reports

Assessment and modeling of stream habitat are integral to understanding streams and the biota within them. In the past several decades, assessment sophistication of ecologic systems increased due to analysis power afforded by gains in computing capability. Spatial data analysis methodology grew alongside computing power and incorporated spatial qualities of ecological data, thereby providing new insights. New methods like geographically weighted regression (GWR) and more established methods like interpolation are now being used in ecological studies to guide assessments and management decisions. However, their accuracy and utility for analysis of stream habitat data have not been fully explored. To clarify …

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …

Nesting Biology Of Osmia Cornifrons: Implications For Population Management, Matthew Mckinney

Graduate Theses, Dissertations, and Problem Reports

The Japanese hornfaced bee, Osmia cornifrons (Hymenoptera: Megachilidae) is a palearctic mason bee managed for the pollination of early season fruit crops such as apple and blueberry. Since its adoption as a managed pollinator in Japan during the 1940s, a large body of literature has amassed with the goal of enhancing O. cornifrons management practices. This research makes important contributions to that literature in two ways. First, the research describes the in-nest relationship of O. cornifrons and the cleptoparasitic mite pest Chaetodactylus krombeini. Distribution of male and female O. cornifrons and of C. krombeini was determined using linear and non-linear …

Potential Effects Of Altered Precipitation Regimes On Primary Production In Terrestrial Ecosystems, Joanna S. Hsu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In addition to causing an increase in mean temperatures, climate change is also altering precipitation regimes across the globe. General circulation models project both latitude-dependent changes in precipitation mean and increases in precipitation variability. These changes in water availability will impact terrestrial primary productivity, the fixation of carbon dioxide into organic matter by plants. In my thesis, I addressed the following three questions: 1.) What will be the relative effect of changes in the mean and standard deviation of annual precipitation on mean annual primary production? 2.) Which ecosystems will be the most sensitive to changes in precipitation? 3.) Will …

A Comparison Of Eastern Gray Squirrel (Sciurus Carolinensis) Nesting Behavior Among Habitats Differing In Anthropogenic Disturbance, Elizabeth Williams

Electronic Theses and Dissertations

Eastern gray squirrels inhabit a large range of heterogeneous habitats and climates, and live with various levels of anthropogenic disturbance. Previous studies have examined this species in unmodified and modified surroundings; however, a comparison of populations between these habitats has yet to be published. Their widespread occurrence coupled with their success in urban areas and the invasive nature of introduced populations, suggests this species is behaviorally flexible. The purpose of this study was to determine the effect of anthropogenic disturbance and development on gray squirrel nesting behavior by comparing variables related to nesting habitat preference among habitats of differing levels …

Being Outside Learning About Science Is Amazing: A Mixed Methods Study, Michelle L. Weibel

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study used a convergent parallel mixed methods design to examine teachers' environmental attitudes and concerns about an outdoor educational field trip. Converging both quantitative data (Environmental Attitudes Scale and teacher demographics) and qualitative data (Open-Ended Statements of Concern and interviews) facilitated interpretation. Research has shown that adults' attitudes toward the environment strongly influence children's attitudes regarding the environment. Science teachers' attitudes toward nature and attitudes toward children's field experiences influence the number and types of field trips teachers take. Measuring teacher attitudes is a way to assess teacher beliefs.

The one day outdoor field trip had significant outcomes for …

Multi-Scale Patch Dynamics Of Coral Communities: A Cross-Caribbean Investigation Using A Landscape Ecology Approach, Brittany Huntington

Open Access Dissertations

The overarching objective of this dissertation was to improve our knowledge of the relationship between seascape heterogeneity and diversity of stony coral assemblages across spatial scales. Coral communities on patch reefs in three regions of the Caribbean were used as a model system to investigating this relationship because patch reef heterogeneity could be readily quantified within the seascape using remote sensing and image analysis techniques. I began with a theoretical approach, exploring the origins of observed species diversity among coral communities at increasing spatial scales. Hierarchical sampling and null models revealed that coral diversity was governed by non-random processes at …

Patterns In The Temporal Variability Of Temperate Reef Fishes And The Implications For Sampling Frequency In Citizen Science Monitoring Programs, Chelsea Parrish-Kuhn

SNS Master's Theses

Ecological monitoring enables our understanding of ecosystem change and is fundamental to the process of developing sound management policies. One major gap in all current California kelp forest monitoring programs is the limited frequency at which kelp forest fishes are sampled. Citizen science has been identified as a valuable tool to help meet monitoring needs in the marine environment, most recently in the California Marine Life Protection Act (1999). Because the costs of citizen science programs are mitigated by the use of volunteers, they are more able to expand their monitoring efforts to capture seasonal variations than other professional programs. …

A Model System In Landscape Genetics – The Insect Inhabitants Of Pitcher Plants, Gordana Gojko Rasic

Electronic Thesis and Dissertation Repository

Landscape genetics is a rapidly growing field that investigates how landscape and environmental features interact with microevolutionary processes to give rise to spatial genetic variation in populations. The ability to predict landscape effects on genetic patterns has been limited by the lack of studies conducted on more than one species, over multiple spatial scales and in replicated landscapes. A system that allows for such studies are the insect inhabitants of the purple pitcher plant (Sarracenia purpurea): the pitcher plant flesh fly (Fletcherimyia fletcheri), the midge (Metriocnemus knabi) and the mosquito (Wyeomyia smithii). In this thesis, I worked towards developing this …

The Conservation Value Of Residential Landscapes For Native Bird Communities: Patterns, Processes, And Management Implications, Susannah Beth Lerman

Open Access Dissertations

Urbanization, as it transforms natural biotic systems into human-dominated landscapes, is recognized as one of the greatest threats to biodiversity throughout the world. Furthermore, urban dwellers are becoming increasingly disconnected with the natural world. Here I investigate whether residential landscape designs that mimic the natural environment can provide habitat for native birds. First I uncover some of the patterns of bird distribution in residential yards by incorporating habitat features, urbanization measurements and socioeconomic factors with bird monitoring data into a multivariate analysis. The results indicate that native birds associate with neighborhoods with native plants and shrubs, neighborhoods closer to desert …

Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy

Electronic Theses and Dissertations

The preservation and quantity of fossil tapirs (Tapirus polkensis) from the Gray Fossil Site in northeastern Tennessee provides a unique opportunity for comparison and analysis of skeletal characters. Intraspecifically, modern tapirs show little to no variation in the morphology of the sagittal crest. However, several different morphologies exist within the sample at Gray. No osteological evidence of sexual dimorphism exists for tapirs, and no correlation between crest shape and sex was observed. Several juveniles display well defined crests, while some adults have only minor thickening of the temporal ridges; therefore, no distinct correlation between age and crest state …

Evolution, Speciation, And Conservation Of Amblyopsid Cavefishes, Matthew Lance Niemiller

Doctoral Dissertations

Cave organisms are classic examples of regressive evolution, as many disparate taxa have evolved similar convergent phenotypes in subterranean environments. While recent phylogeographic and population genetic analyses have greatly improved our understanding of the evolutionary and biogeographic history of cave organisms, many questions remain unanswered or poorly investigated. I investigated several evolutionary and biogeographic questions in a model system for regressive evolution and studies of ecological and evolutionary mechanisms, amblyopsid cavefishes. In chapter I, I used recently developed methods to delimit species boundaries and relationships in a widely distributed cavefish, Typhlichthys. I show that species diversity in Typhlichthys is …

Genetic Differentiation Of A Sympatric Lake-Resident/Anadromous Species Pair Of Threespine Stickleback In Mud Lake, Alaska, Cory J. Drevecky

College of Liberal Arts & Social Sciences Theses and Dissertations

The formation of new species is responsible for all the biological diversity we see on Earth. This process of speciation is not yet fully understood and is most often studied by comparing individuals of closely related species. The threespine stickleback, Gasterosteus aculeatus, a fish species complex found in marine and coastal freshwater environments of the northern hemisphere, has become a model species used to study speciation. Many morphological and genetically divergent forms within this complex have adapted to freshwater conditions. Studying the mechanisms that allow stickleback to adapt to freshwater conditions has provided much insight into the process of speciation. …

Evaluating The Effects Of Morrow's Honeysuckle Control On Vertebrate And Vegetation Assemblages, And Small Mammal Foraging Ecology At Fort Necessity National Battlefield, Charnee Lee Rose

Graduate Theses, Dissertations, and Problem Reports

Exotic, Japanese bush honeysuckles (Lonicera spp.; Caprifoliaceae) are tied to a variety of impacts on wildlife and ecosystems. Morrow's honeysuckle (Lonicera morrowii) has become a persistent invader in eastern North America. We organized a restoration initiative at Fort Necessity National Battlefield (FONE), Pennsylvania, USA from 2004--2010. Concurrently, we studied the consumption of Morrow's honeysuckle fruits by small mammals from October--November 2009 and July--August 2010, and determined habitat variables that affected visitation rate to foraging stations. Areas of FONE were invaded by Morrow's honeysuckle after the land had been cleared for agriculture, and routine mowing ceased in the mid-1980s. Our restoration …