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Phylogeography Of The Polychaete Phragmatopoma Californica (Family Sabellarididae) In The Southern California Bight (Scb), Praneeth Kamana

Student Theses and Dissertations

This study measured the genetic differentiation among populations of Phragmatopoma californica and compared this genetic structuring with another polychaete species (Neries grubei) having a different life history. A total of 234 samples from 13 populations of the sabelleriid polychaete Phragmatapoma californica (Fewkes) from six mainland sites along the southern California coast and two Channel Islands were studied by way of inter simple sequence repeats (ISSRs) to determine genetic diversity, divergence and to estimate gene flow among populations. The results were compared to another polycheate species, Neries grubei which has a shorter larval development than P. californica, reducing potential dispersal and …

Geologic Composition Influences Distribution Of Microbiotic Crusts In The Mojave And Colorado Deserts At The Regional Scale, Rebecca E. Drenovsky, Nicole Pietrasiak, Jeffrey R. Johansen

Biology

Abiotic and biotic factors influencing distribution of microbiotic crusts within hot deserts, such as the Mojave and Colorado Deserts, are poorly known. Our objective was to examine microbiotic crust distribution with reference to soil and parent material characteristics as well as plant functional groups in wilderness areas of Joshua Tree National Park (JTNP). A total of 75 sites were visually assessed for crust abundance and plant community composition; soil physical and chemical factors also were measured. Microbiotic crusts of JTNP, in particular lichen and moss crusts, were not as well-developed or as widely distributed as in other arid regions of …

Economic Impacts Of Drought On Kentucky Corn, Hay, And Soybeans, Kortney E. Craft

Masters Theses & Specialist Projects

Understanding climatic impacts is important if we are to comprehend the relationship between climate and society. Weather phenomena can have environmental, economical, and social impacts. Drought is the natural hazard that affects people the most. It is also the most complex and least understood. There is no one universally accepted definition for drought which makes its examination difficult. Droughts’ duration is also difficult to determine because it has no clearly defined onset and end. Also, drought varies both geographically and temporally making uniform drought monitoring difficult. Since drought is difficult to monitor and access, drought impacts are often poorly documented. …

The Assembly Of Ecological Communities Inferred From Taxonomic And Functional Composition, Eric R. Sokol, E. F. Benfield, Lisa K. Belden, H. Maurice Valett

Biological Sciences Faculty Publications

Among-site variation in metacommunities (beta diversity) is typically correlated with the distance separating the sites (spatial lag). This distance decay in similarity pattern has been linked to both niche-based and dispersal-based community assembly hypotheses. Here we show that beta diversity patterns in community composition, when supplemented with functional-trait information, can be used to diagnose assembly processes. First, using simulated data, we show how the relationship between distance decay patterns in taxonomic and functional measures of community composition can be used to predict the influence of a given trait on community assembly. We then use the patterns generated by the simulation …

Effects Of Soil Biota From Different Ranges On Robinia Invasion: Acquiring Mutualists And Escaping Pathogens, Ragan M. Callaway, Eulogio J. Bedmar, Kurt O. Reinhart, Cinta Gómez Silvan, John Klironomos

Biological Sciences Faculty Publications

The net effects of soil biota on exotic invaders can be variable, in part, because net effects are produced by many interacting mutualists and antagonists. Here we compared mutualistic and antagonistic biota in soils collected in the native, expanded, and invasive range of the black locust tree, Robinia pseudoacacia. Robinia formed nodules in all soils with a broad phylogenetic range of N-fixing bacteria, and leaf N did not differ among the different sources of soil. This suggests that the global expansion of Robinia was not limited by the lack of appropriate mutualistic N-fixers. Arbuscular mycorrhizal fungi (AMF) from the …

Spatiotemporal Modeling Of Threats To Big Sagebrush Ecological Sites In Northern Utah, Alexander J. Hernandez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study tested the performance of classification, regression, and ordination techniques to evaluate the spatiotemporal dynamics of threats to big sagebrush ecological sites. The research was focused on invasion by annual exotic grasses and encroachment by woodlands.

We sought to identify those areas that have had a persistent coverage of cheatgrass (Bromus tectorum) in big sagebrush ecological sites. We took advantage of the contrast in greenness between multi-temporal (within one year) remotely sensed vegetation indices captured in the spring and summer to find a distinct phenological signature that allowed mapping cheatgrass. We utilized support vector machines (SVM) to classify three …

The Role Of Historical And Contemporary Processes On Phylogeographic Structure And Genetic Diversity In The Northern Cardinal, Cardinalis Cardinalis, Brian T. Smith, Patricia Escalante, Blanca E. Hernandez-Banos, Adolfo G. Navarro-Siguenza, Sievert Rohwer, John Klicka

Ornithology Program (HRC)

Background

Earth history events such as climate change are believed to have played a major role in shaping patterns of genetic structure and diversity in species. However, there is a lag between the time of historical events and the collection of present-day samples that are used to infer contemporary population structure. During this lag phase contemporary processes such as dispersal or non-random mating can erase or reinforce population differences generated by historical events. In this study we evaluate the role of both historical and contemporary processes on the phylogeography of a widespread North American songbird, the Northern Cardinal, Cardinalis cardinalis …

Analysis And Interpretation Of Factors Leading To Increased Aids Prevalence In Sub-Saharan Africa, William Kalhorn

Department of Environmental Studies: Undergraduate Student Theses

My thesis research project focuses on the major factors that are contributing to the worst disease epidemic on the planet today. I have aimed to determine what may be some of the most important factors contributing to highly variable difference in HIV/AIDS prevalence rates are among the regions of East, West, and South Africa.  The HIV/AIDS epidemic has been growing and expanding to new areas of the world since the first case arose in 1959 in what is now called Kinshasa, Congo (Avert, 2011). The AIDS/HIV epidemic is believed to have originated on the African continent, and this is where …

An Assessment Of Stable Hydrogen-Isotope Analysis Methods To Assign Geographic Origin To Migratory Red-Tailed Hawks (Buteo Jamaicensis), Carla Marie Ahlschwede

Department of Environmental Studies: Undergraduate Student Theses

Stable-hydrogen isotopes are becoming an increasingly popular method of studying migratory birds, though sample preparation methods may affect results.  In this study I examined feathers from red-tailed hawks (Buteo jamaicensis) to determine the relationship between measure of δD due to inter-feather variation or drying methods, assessed the accuracy of results by using two birds of known-origin and estimated possible natal origins of migratory red-tailed hawks.  Two feathers per individual were taken from 81 wild hawks caught at Hitchcock Nature Center near Crescent IA and from 2 rescued red-tailed hawks, Raptor Recovery Nebraska near Eagle, NE. 119 of the …

Analysis Of The Threat Of Genetically Modified Organisms For Biological Warfare, Jerry B. Warner, Alan J. Ramsbotham Jr., Ewelina Tunia, James J. Valdes

Defense and Technology Papers

This study seeks to better understand the evaluation of the potential threats posed by advances in biotechnology, especially genetically modified organisms and synthetic biology. It narrows the scope of consideration into two parts: defining a catastrophic biological attack focused on bioterrorism and that this attack would be restricted to the United States.

Forest Resource Access, Dependency, And Vulnerability In Southeast And Southcentral Alaska, Mekbeb E. Tessema

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rural communities in the western U.S. and Alaska are highly dependent upon surrounding publicly-owned forests for various economic and non-economic values. Historically, limited data has hampered the understanding of such community-resource linkages. As a result, community interests may not be adequately considered in forest management plan development and policy formulation. Addressing this imbalance is an important issue for the U.S. Forest Service (USFS), particularly as it shifts from timberdominated goals to a more holistic ecosystem-based form of management.

This study seeks to understand community-resource use linkages, dependency, and vulnerability surrounding the Chugach and Tongass NFs using place-level socioeconomic data from …

Characterization Of Piedmont Prairie Sites In North And South Carolina, James Benson

All Dissertations

Grassland habitats have essentially disappeared from the Piedmont. This study was conducted to determine which site characteristics in remnant Piedmont prairie sites could be used as indicators of suitable sites. Eight prairie remnant sites located in the Piedmont of North and South Carolina were evaluated based on soil series, slope, aspect, landform index, temperature, and precipitation. Geographic Information System technology was used to create layers of these characteristics to predict potential restoration sites throughout the North and South Carolina Piedmont. It was found that southern aspects, slopes generally less than 15%, upper slope positions, and occurrence on Enon (Fine, mixed, …

Molecular Evolution And Historical Biogeography Of New World Birds, Brian T. Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Deciphering the patterns of how biodiversity has evolved across time and space has remained a fundamental objective for biologists for the last 200 years. Researchers are faced with the challenge of interpreting the complexity of evolutionary patterns that have been generated over the deep history of the Earth. The advancement of DNA sequencing technology has yielded a new and powerful genetic toolkit that has allowed biologists to address novel evolutionary questions. For my dissertation research, I used molecular genetics and a statistical framework to study the evolution and historical biogeography of birds distributed in North and South America. My dissertation …

Planning For Building-Integrated Agriculture In Las Vegas, Robert Vralsted

UNLV Theses, Dissertations, Professional Papers, and Capstones

High food prices, concern about food nutrition and safety, and an awareness of commercial farming's environmental impact have generated a renewed interest in sustainable urban agriculture. Advances in controlled environment agriculture (CEA) have made it possible to grow food virtually anywhere in a much more sustainable manner than traditional field-based agriculture. Locating and planning urban farms using retrofitted existing building stock to maximize food production and ease of distribution in Las Vegas requires consideration of multiple barriers related to geography, economics, and the built environment. Consideration of these factors in the planning process informs the design of a successful BIA …

Species Diversity And Seasonal Abundance Of Scarabaeoidea At Four Locations In South Carolina, Kevin Hinson

All Theses

ABSTRACT
Using light, flight-intercept, and pitfall traps, 74, 327 specimens of Scarabaeoidea were captured at four golf courses in South Carolina during 2009-2010. Aphodiinae were identified only to the subfamily level and totaled 57,502 specimens. 16,825 specimens in 47 genera and 104 species in the families Ceratocanthidae, Geotrupidae, Hybosoridae, Lucanidae, Passalidae, Scarabaeidae (excluding Aphodiinae), and Trogidae were identified based on morphological characteristics. Similar to other southeastern studies focusing on phytophagous scarabs, the most abundant species consisted of Dyscinetus morator (Fabricius), Euetheola humilis (Burmeister), Cyclocephala lurida Bland, and Hybosorus illigeri Reiche. The most speciose genus captured was Phyllophaga Harris, totaling 22 …

2011 - The Sixteenth Annual Symposium Of Student Scholars

Symposium of Student Scholars Program Books

The full program book from the Sixteenth Annual Symposium of Student Scholars, held on April 26, 2011. Includes abstracts from the presentations and posters.

An Exploration Of Pharmacognosy And Its Potential In The Multi-Faceted Solution Required To Address Hiv/Aids In Sub-Saharan Africa, Alexandra Sassi

Pell Scholars and Senior Theses

This work has both both biological and anthropoligcal foci. It addresses research done on the medicinal properties of plants and how this research could make positive contributions to the current social and biological issues surrounding the HIV/AIDS epidemic in sub-Saharan Africa.

Judy Hendrix, Judy Hendrix, Institute Of Child Nutrition. Child Nutrition Archives.

Oral History Project (all interviews)

After college Judy Hendrix taught home economics, science, and geography at different times before getting into the child nutrition field. Hendrix then worked as a school nutrition director for one year before becoming an area consultant for school nutrition with the Georgia Department of Education. After working as an area consultant in various Georgia locations for a number of years, Hendrix returned as a food service director for a large school district, where she worked for a further four years before retirement.

A ‘Driving Force’ In Developing The Nation’S Forests: The Mcintire-Stennis Cooperative Forestry Research Program., Steven H. Bullard, Perry J. Brown, Catalino A. Blanche, Richard W. Binker, Don H. Thompson

Faculty Publications

The McIntire-Stennis (M-S) Cooperative Forestry Research Program has provided fundamental support for creating and strengthening forestry research and graduate training efforts at colleges and universities across the nation for nearly 50 years. M-S funding has helped produce thousands of forestry scientists and other research professionals, and M-S–supported research has provided critical basic understanding and applied solutions to extend the benefits that flow from forests and related rangelands across the nation over time. The 1962 legislation that created the M-S program authorized funding of up to one-half of the funds appropriated for federal forestry research conducted directly by the USDA. Throughout …

Review Of Nature's Ghosts: Confronting Extinction From The Age Of Jefferson To The Age Of Ecology. By Mark V. Barrow, Jr., Peter A. Bednekoff

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

The saving of bison occupies a central place in Nature's Ghosts, but Mark Barrow's chronicle extends over a century both before and after. The story starts with Thomas Jefferson and fossils that came to be recognized as mastodons, mammoths, and giant ground sloths. "Jefferson and most of his contemporaries were certain that the natural world was orderly, static, and new." In such a worldview, extinction was unthinkable. Fossil evidence plus the historical extinctions of dodos, moas, and great auks forced reconsideration.

This book ranges across centuries and continents, and only a few parts of it are explicitly about the Great …

Vegetation Classification And Mapping Of Homestead National Monument Of America, Project Report, Kelly Kindscher, Hayley Kilroy, Jennifer Delisle, Quinn Long, Hillary Loring, Kevin Dobbs, Jim Drake

United States National Park Service: Publications

Executive Summary

Homestead National Monument (HOME) was created at the to celebrate the significance of the Homestead Act of 1862 which granted 160 acres of free land to claimants and was one of the most significant and enduring events in the westward expansion of the United States. The National Monument encompasses 184 acres in Gage County, west of Beatrice, Nebraska. This unique site also hosts the oldest prairie restoration in the National Park system, and the second-oldest tallgrass prairie restoration known. This park unit also has a small remnant of native tallgrass prairie and remnants of bur-oak forest.

A three-year …

Adult Female Activity Time Budgets In Red-Bellied Lemurs (Eulemur Rubriventer) And Infant Survival: Ranomafana National Park, Frances Hardy

Independent Study Project (ISP) Collection

My research during the independent study period focuses on the relationship between activity time budgets of adult female red-bellied lemurs (Eulemur rubriventer) and infant survival. I conducted my research under the guidance of Centre ValBio in Ranomafana National Park. Red-bellied lemurs have a clear three month birth peak from Aug-Oct, but up to 30% of infants in a single year can be born outside of this birth peak, however, survival for out-of-season infants is strikingly low compared to in-season infants, 100% (n=4) of out-of-season infants died in one study conducted in 2009, whereas only 11% (n=18) of in-season …

Dayton, Ohio: A Study, Nolan Nicaise

Honors Theses

The urban forest is an important element of cityscapes today. Urban trees provide a habitat to wildlife populations, create more tolerable city living conditions, and better the lives of residents around them. The urban forest, however, is not distributed equitably to the urban population, and some residents receive more or less of its positive externalities. Montgomery County, Ohio, was chosen as the study site to determine if environmental injustice was present regarding the urban forest. It was found that there was environmental injustice present in Montgomery County, as the density of the urban forest was limited by the educational obtainment …

Monitoring Nesting Trends And Hatchling Success Of The Green Turtle (Chelonia Mydas) Population On Mnemba Island, Zanzibar, Taylor Dunbar

Independent Study Project (ISP) Collection

The nesting trends and hatching success of Green sea turtles (Chelonia mydas) were studied on Mnemba Island. This study involved a continuation of data collection for the ongoing monitoring program of sea turtles on Mnemba Island. Data was collected from nesting females as well as from post hatching nest excavations. The data that has been collected over the course of ten years was then analyzed to examine trends over time as well as to assess the current status of the turtle population on Mnemba Island. Hatch success as a function of different seasons was analyzed. It has been concluded that …

Validating The Culture Of Agriculture: Farmers Groups And Organic Agriculture Mitigating Rural To Urban Migration In Bhutan, Emma Dosch

Independent Study Project (ISP) Collection

Agricultural occupations make up the largest proportion of Bhutan’s workforce. Over the past two decades the occupation has shrunk from 90% to 65% of Bhutan’s employment. The younger generation of Bhutan’s rural population is seeking livelihood opportunities in urban areas, leaving farms with labor shortages. The movement may compromise the identity and sustainability of Bhutan’s rural population and undermine the nation’s goals of Gross National Happiness (GNH) directed policy. Initiatives to retain and legitimize agricultural livelihoods are emerging inside and outside of government policy. Existing efforts are models of ways to reconnect educated individuals with the needs and values of …

Cottonwood Riparian Site Selection On The Cheyenne River Sioux Reservation, Julie A. Thorstenson, Diane Rickerl, Janet H. Gritzner

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

The construction of the Oahe Dam on the Missouri River eliminated thousands of acres ofriparian and floodplain lands on the Cheyenne River Sioux Reservation in South Dakota. Restoration is needed to replace wildlife habitat. This study focused on site selection for native cottonwood (Populus deltoides Bartr. Ex Marsh. ssp. Monilifers (Ait.) Eckenwalde) restoration to help mitigate this loss. Geographic information systems technologies were used to develop a suitability model for cottonwood restoration. Tribal lands were extracted from a digital dataset oflandownership. Those touched by or included in a 46 m border of the Moreau River were candidate sites. Of …

Historic And Contemporary Trends Of The Conservation Reserve Program And Ring-Necked Pheasants In South Dakota, Christopher R. Laingen

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Over the past century, the interactions between agricultural land use and government cropland retirement programs have affected pheasant population change. Two government land retirement programs that returned croplands to grasslands, Soil Bank in the 1960s and the current Conservation Reserve Program (CRP), help to illustrate these connections. From 2007 to 2010, South Dakota lost 41% of its CRP lands and experienced an 18% decline in pheasants per mile. However, because of where CRP expirations have occurred and where pheasant populations are found, some regional variability is seen. Western South Dakota (Region 1) had an 80% increase in pheasants per mile …

Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis

School of Biological Sciences: Dissertations, Theses, and Student Research

Accurate knowledge of species boundaries and species phylogeny are fundamental to testing hypotheses of recent evolutionary processes, but the estimation of these partitions is challenging due both to inherent confusion about what is being estimated as well as the data available to estimate them. Using multilocus data from mtDNA, microsatellites, and nuclear locus sequences of over 1100 individuals, we delimited eight separately evolving species of Cichla rather than the 15 described. Among species we found evidence of rare but widespread introgressive hybridization, while within these species we observed evidence of long-term gene exchange and constrained evolutionary trajectories. In most cases …

Evaluation And Analysis Of Beef Contamination By Low Levels Of Ammonia, Sely Prajitna

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Leakage of ammonia in food facilities has been known to occur in the past. Ammonia leaks often lead to food contamination in food plants and can cause illness among consumers who accidentally consume the food products contaminated with high levels of ammonia. Therefore, a rapid, simple yet accurate method has to be established for on-site ammonia level screening in food plants to ensure the food is safe. One of the primary objectives in this study was to verify and optimize an ion selective electrode (ISE) method for its accuracy and reproducibility in determining ammonia in meat. Different extraction procedures (blending …

Poster Session, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Fate of Stable Isotope Label During Predation of 15N-Tagged Wild-Type Escherichia coli by Protozoa, Ashley Barton and Alan Fryar, Dept Earth and Environmental Sciences, UK
• Cane Run Watershed Assessment and Restoration – Phase One Accomplishments, Amanda Gumbert and others, UK Cooperative Extension Service
• Improving Water Quality: Riparian Edge versus River Channel, Renee Kirtman and Kristy Hopfensperger, Biological Sciences, Northern Kentucky University
• Microscopic Population Dynamics and their Relationships to the Activated Sludge Process in a 30 MGD Wastewater Treatment Plant, Maria Lundin and David Price, LFUCG Division of Water Quality
• Southern Region Down-Well Camera Project, Glynn …