Physical Sciences and Mathematics Commons^™

Effects Of Multiple Stressors On Aquatic Macroinvertebrate Communities In A Mixed-Land-Use Watershed, Joellen Stivala

Graduate Theses, Dissertations, and Problem Reports

As urbanization continues, there is a need to identify and understand environmental stressors that impact stream condition in mixed-land-use watersheds. This study analyzed four years of aquatic macroinvertebrate community and environmental data collected from ten sites located at the mouths of first-order tributaries and along the main stem creek of a 23-km², mixed-land-use watershed in central Appalachia. The main objectives were to 1) determine stream ecological integrity by analyzing stream macroinvertebrate taxonomic and trait-based composition and 2) assess which of 23 environmental variables explained significant variability in common community composition metrics (WVSCI, GLIMPSS, Biotic Index, % clingers, etc.). …

La Habana: A History Of Society, Livelihood, Movement, And Land Use On The Iquitos-Nauta Highway, Katie Brown

Undergraduate Honors Theses

With increasing infrastructural projects and land titling in the Peruvian Amazon, many changes are occurring within small roadside communities. In this case study, we investigate how these changes impact livelihoods, land use, travel patterns, and social relations within the broader concepts of development, privatization of land, and commodification of nature. Specifically we focus on the caserío La Habana situated on the Iquitos-Nauta highway in the Loreto region of Peru. Semi-formal interviews and ethnographic methods were conducted to gather information on social organization, history of the community, land use practices, migration patterns, opinions on the road, and livelihood strategies. After data …

Agricultural Intensification In The Midwest: Impacts On Regional Surface Humidity, Andrew Hill

All Graduate Theses, Dissertations, and Other Capstone Projects

An overwhelming majority of anthropogenic climate change studies have placed emphasis on biogeochemical agents, chiefly carbon dioxide emissions, which operate on a global scale. Fewer studies focus on biophysical factors such as land use/ land cover which operate on a regional or local scale. The impact from biophysical factors will continue to be reinforced with a growing human population and expanding resource demands. Of these factors, agricultural land use represents one of the largest, most extensive, and vital land use allocations.

The U.S. Midwest, dominated by rain-fed corn and soybean agriculture, is a key agricultural region which is lacking in …

Application Of Molecular Pathology Techniques To Understand Mechanisms Of Disease In Smallmouth Bass, Heather Leigh Walsh

Graduate Theses, Dissertations, and Problem Reports

In the Chesapeake Bay drainage, smallmouth bass Micropterus dolomieu are used as an indicator species of estrogenic contaminant exposure and have been implicated in fish kills and disease since 2005. In the Potomac River drainage, adult smallmouth bass have experienced mortality and disease and males have a high prevalence of intersex (testicular oocytes). Conversely, in the Susquehanna River drainage mortalities and disease of young-of-the-year smallmouth bass (YOY SMB) have occurred and resulted in a population shift to older and larger fish. The exact cause of these events remains unknown; however, factors such as poor water quality, contaminants, pathogens and parasites, …

Antibiotics And Antibiotic-Resistant Bacteria In Coastal Plain Streams, Jason Duff

Electronic Theses and Dissertations

Streams across the United States and globally are influenced by environmental contamination, including antibiotics, which enter streams due to widespread use and multiple pathways into the environment. Antibiotics are also likely to enter streams in mixture with other contaminants that alter the effects on aquatic organisms. Furthermore, antibiotic-resistant bacteria enter streams through similar pathways as antibiotics with implications for natural microbial communities. Therefore, understanding the presence and effects of antibiotic-contaminant mixtures and antibiotic-resistant bacteria in streams is important for resource management.

Chapter one describes an experiment that tested the hypothesis that the antibiotic tetracycline (TC) alone influences phytoplankton communities differently …