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The Effect Of Edge-Of-Field Nutrient Management Practices On Microbial Concentrations In Subsurface Drainage Water And The Associated Risk Of Antibiotic Resistance Dissemination, Sara Mardani

Electronic Theses and Dissertations

Many in-field and edge-of-field management practices have been used to reduce nutrient loads from agricultural fields. The denitrification woodchip bioreactor (WB) is one edgeof- field management practice that has proven to be effective in removing nitrate from subsurface drainage water. The success in nitrate removal achieved with WBs has raised interest in expanding their capabilities for removing other agricultural pollutants, including phosphorus, by using other types of media like phosphorus-sorbing filters or combining these filters with woodchips to remove both nitrate and phosphorus as dual-nutrient removal systems. Despite the extensive research done on WBs and nutrient filter materials, little consideration …

Effects Of Fragmentation On Species Retention In National Parks, Liz Tanner

Master's Theses or Doctor of Nursing Practice

The North American landscape is becoming increasingly fragmented, resulting in habitat patches with decreased area and increased isolation. Often, these patches exist as protected areas, such as national parks. The Theory of Island Biogeography is frequently used as a model for these patches, where each park serves as an ‘island’ surrounded by a ‘sea’ of human-altered habitats. As such, species richness and extinctions in a park might be explained by its area. For this study, I used regression models to examine the relationship between richness and area, as well as extinctions and area, for mammals and birds in national parks. …

Application And Refinement Of Molecular Ecology Techniques For Amphibian Conservation, Stephanie Marie Burgess

Electronic Theses and Dissertations

Wildlife conservation has become increasingly difficult due to habitat loss habitat fragmentation and land use change. Thus conservationists have embraced advances in molecular ecology such as landscape genetics and microbial bioinformatics that employ genetic techniques to further understand the relationship between individuals and their environment. In landscape genetics model inferences can be used to identify features that facilitate or resist gene flow providing a framework for anticipating the impacts of land use changes on a species’ ability to disperse. However the factors that affect the transferability of landscape genetics inferences are poorly understood and little is known about the effect …

Island Invasion: The Silent Crisis In Hawaii, Sophia Janssen

Pomona Senior Theses

Keeping out invasive species may, upon first review, seem like a trivial environmental cry from ecologists and deep environmentalists; a belated wish to return to an undeveloped world where nature was pristine. However invasive species create problems that impact all of us and can have far more severe consequences than changing a stunning landscape. These problems are heightened in islands like Hawaii, where the fragile ecosystems have developed over centuries of evolution and adaptation. The introduction of a disease-carrying mosquito can put the people of Hawaii at risk to many vector-born illnesses and create an epidemic, taking human life. The …

Does Helping-At-The-Nest Help? The Case Of The Acorn Woodpecker, Walter D. Koenig, Eric L. Walters, Sahas Barve

Biological Sciences Faculty Publications

Cooperative breeding groups often involve "helpers-at-the-nest"; indeed, such behavior typically defines this intriguing breeding system. In few cases, however, has it been demonstrated that feeding nestlings by helpers, rather than some other behavior associated with helpers' presence, leads to greater reproductive success. One prediction of the hypothesis that feeding behavior per se is responsible for the fitness benefits conferred by helpers is that there should be close congruence between the patterns of helping-at-the-nest and the fitness effects of helpers. Here we look for such a relationship in the cooperatively breeding acorn woodpecker (Melanerpes formicivorus) in order to begin …

Improving Access To Clean Water In Rural Ecuador: The Connection Between Willingness To Pay And Population Health, Micalea Leaska

Capstone Collection

Climate change is affecting social and environmental determinants of health through access to safe drinking water, safely managed sanitation systems, and access to health care services and the ability for individuals to break free from unsuitable circumstances. Ecological disturbances such as those caused by climate change can cause a shift in host vectors or a change in habitat that results in a greater likelihood of the pathogen coming in contact with humans. Water, sanitation, and hygiene (WASH) services and their accessibility to populations can directly impact a community’s vulnerability to diseases and limiting factors to increase economic growth. If rural …

Annual And Seasonal Measurements Of Home Ranges And Habitat Use By Female Elk (Cervus Elaphus) In Northwestern Minnesota, Alicia E. Freeman

All Graduate Theses, Dissertations, and Other Capstone Projects

Elk were present historically in Minnesota’s prairies and forest transition zone up until their extirpation from the state in the late 1800s (Hazard 1982, Minnesota Department of Natural Resources [MNDNR] 2017). Settlers moving into the region converted much of the land for agricultural purposes, significantly reducing the amount of habitat available for elk, and ultimately leading to their extirpation in the early 1900s. Elk returned to the state in the 1930s through a reintroduction effort, as well as through natural dispersal from North Dakota USA, and Manitoba Canada in the 1980s (MNDNR 2017). In 2016, the Minnesota Department of Natural …

Seascape Genetics And Rehabilitation Efficiency In The Florida Manatee, Madison Hall

Electronic Theses and Dissertations

The Florida manatee (Trichechus manatus latirostris) was recently downlisted federally from "endangered" to "threatened" despite acknowledgments of remaining threats to long term population persistence. Challenges to future manatee conservation include, but are not limited to, increases in frequency of harmful algal blooms, intensifying anthropogenic disturbance, and loss of warm-water habitat. The goals of this dissertation were 1) to assess threats to the manatee via a comprehensive, long-term (1973-2016), retrospective analysis of the manatee rescue and rehabilitation partnership (MRRP) and 2) to use seascape genetics analysis to examine whether abiotic, biotic, or anthropogenic seascape variables could significantly describe genetic distance patterns …

Through The Eyes Of Locals: A Changing Climate In Bolivia, Jacob D. Rex

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Deforestation and Agricultural Land-Use Change in Bolivia as a Function of Socio-Economic Realities.

This research combines semi-structured interviews of key informants and local participants, as well as field observations, which were conducted between January and April of 2019 in the Departments of Santa Cruz & Chuquisaca.

Loss Of A Foundation Species, Eastern Hemlock (Tsuga Canadensis), May Lead To Biotic Homogenization Of Fungal Communities And Altered Bacterial Abundance In The Forest Floor, Aliza Fassler, Jesse Bellemare, Danielle D. Ignace

Biological Sciences: Faculty Publications

Tsuga canadensis (Eastern Hemlock) is a key forest foundation species that is currently declining across the eastern US due to attack by exotic insect species, primarily Adelges tsugae (Hemlock Woolly Adelgid). In the northeastern US, declining Eastern Hemlock stands are typically replaced by fast-growing deciduous Betula lenta (Black Birch) trees, altering ecosystem processes and ecological communities. In this study, we used an approach that substituted space for time to explore how the forest floor's soil organic horizon, macrofungal communities, and bacterial abundance might be altered following Eastern Hemlock replacement by Black Birch. We compared intact, mature Eastern Hemlock forest plots …

Strategies For Small Business Sustainability, Victor K. Adoukonou

Walden Dissertations and Doctoral Studies

Small businesses represent more than 99% of all employers in the United States, but more than 50% of small businesses have failed before 5 years. Climate change, digitization, and social media contribute to a paradigm shift in consumers' habits, as more consumers have become environmentally and social justice conscious. Business leaders who are unable to follow the consumers' trends and changes of habit may not succeed in sustaining their businesses. The purpose of this multiple case study was to explore strategies owners of small businesses in the District of Columbia use to sustain their businesses for longer than 5 years …

Decomposing A Watershed’S Nitrate Signal Using Spatial Sampling And Continuous Sensor Data, Evan Clare

Theses and Dissertations--Civil Engineering

Watershed features, physiographic setting, geology, climate, and hydrologic processes combine to produce a time-variant nutrient concentration signal at the watershed outlet. Anthropogenic influences, such as increased agricultural pressures and urbanization, have increased overall nutrient loadings delivered to the fluvial network. The impact of such increased nutrient loadings on Kentucky’s drinking water remains a potential threat to the region.

By coupling spatial sampling of nitrate concentrations in surface water with contemporary nutrient and water quality sensor technology, a decomposition of the Upper South Elkhorn watershed’s nitrate signal and an estimation of source timing and loading in the watershed was completed. The …

Evaluating Reforestation Options For Surface Mines In Appalachia, Joseph Frederick

Theses and Dissertations--Forestry and Natural Resources

During the last century coal extraction has degraded ecosystems in Appalachia, converting forested land into other cover types that have a diminished capacity to naturally progress to later stages of succession. This projects objective was to examine two options for land-use that can assist in returning the reclaimed surface mines to forested cover types, with increased ecosystem services, and a potential for economic gain.

This project examined a biomass plantation and an American chestnut trial. In the biomass trial, greatest heights for American sycamore (12.3 m) and black locust (8.0 m) were found in the fertilizer plots. Mean individual tree …

Long-Term Carbon And Copper Impact On Nutrient Removal Via Green Sorption Media In Dynamic Linear Ditch Environments, Diana Ordonez

Electronic Theses and Dissertations

Nutrient-laden stormwater runoff causes environmental and ecological impacts on receiving water bodies. Biosorption Activated Media (BAM) composed of the sand, tire crumb, and clay have been implemented in stormwater best management practices due to its ability to efficiently remove nutrients from stormwater runoff, such as in roadside linear ditches, via unique chemophysical and microbiological processes. In this study, a set of fixed-bed columns were set up to simulate some external forces in roadside linear ditches and examine how these external forces affect the performance of BAM. In our experiment, scenario 1 simulates the impact that animals such as tortoises, moles …

Wood Creek Tidal Marsh Enhancement Project Benthic Macroinvertebrate Monitoring Report 2019, Alex T. Morrison, Jett W. Hagerty, Claire M. Branson

Environmental Science & Management Senior Capstones

The focus of this report was to monitor benthic macroinvertebrate communities on the Freshwater Farms Reserve, which underwent two phases of restoration as part of the Wood Creek Tidal Marsh Enhancement Project in 2009-2010 and 2016-2018. Objectives for the restoration activities were to increase winter rearing refugia habitat for several threatened/endangered fish species such as the tidewater goby (Eucyclogobius newberryi), Coho salmon (Oncorhynchus kisutch) and steelhead trout (Oncorhynchus mykiss). The goals of this project were to (1) sample and identify BMIs along a salinity gradient in Wood Creek; (2) assess water quality; and (3) …

The Search For Microbial Martian Life And American Buddhist Ethics, Daniel S. Capper

Faculty Publications

Multiple searches hunt for extraterrestrial life, yet the ethics of such searches in terms of fossil and possible extant life on Mars have not been sufficiently delineated. In response, in this essay I propose a tripartite ethic for searches for microbial Martian life that consists of default nonharm toward potential living beings, default nonharm to the habitats of potential living beings, but also responsible, restrained scientific harvesting of some microbes in limited transgression of these default nonharm modes. Although this multifaceted ethic remains secular and hence adaptable to space research settings, it arises from both a qualitative analysis of authoritative …

Application Of A Distributed Hydrologic Model For The Analysis Of Land Use Change In Kedougou, Senegal, Francisco Perez

Dissertations, Master's Theses and Master's Reports

West Africa has experienced extensive land use/land cover (LULC) change since the Sahel drought of the 1970s and 80s. Demographic changes, rapid urbanization, and other anthropogenic impacts on land cover in West Africa have potentially altered hydrological regimes. This work was undertaken while I served as a Peace Corps Volunteer in the Kedougou region of Senegal, an area that has experienced significant and rapid infrastructural improvements and urbanization since the early 2000s. The Gambia River flows near Kedougou, where flooding is an extensive problem, making access and livelihood practices difficult during the rainy season. Changes in climate and land use …

Best Practices To Encourage Landfill Diversion In Waste Management Programs, Sondra Abruzzo

Scripps Senior Theses

Waste generation in the United States is at an all time high. Over half of the country’s waste goes to landfill, yet 70 percent of this waste can be recycled or composted. Since landfills pose one of the largest manmade threats to the environment, sustainable waste management strategies should focus on landfill diversion. A successful waste recovery program needs to engage the public, and ensure individuals participate correctly in available waste management systems. This paper sheds light on effective education and awareness strategies used to encourage participation in local waste management systems and promote landfill diversion. By highlighting successful programs …

Mob Grazing Results In High Forage Utilization And Reduced Western Snowberry Size, Heidi Reed, Sharon Clay, Alexander Smart, David Clay, Michelle Ohrtman

Agronomy, Horticulture and Plant Science Faculty Publications

Mob-grazing strives to maximize forage utilization and minimize selective grazing by using high stocking densities in small paddocks for short durations (12–24 hr). Rotational-grazing uses low stocking densities for a longer time period, retaining about half of the original available forage; although selective grazing can occur. Three cattle (Bos taurus × Bos indicus) grazing intensities: mob- (stocking densities from 32,000 to 67,000 kg ha−1; duration—24 hr); rotation (stocking density—2500 kg ha−1; duration—35 d); and non-grazed systems were compared based on forage utilization and changes to western snowberry (Symphoricarpos occidentalis) (WS) patch volume in a 2-year South Dakota study. …

Looking To The Future: Key Points For Sustainable Management Of Northern Great Plains Grasslands, Lora B. Perkins, Marissa Ahlering, Diane L. Larson

Natural Resource Management Faculty Publications

The grasslands of the northern Great Plains (NGP) region of North America are considered endangered ecosystems and priority conservation areas yet have great ecological and economic importance. Grasslands in the NGP are no longer self-regulating adaptive systems. The challenges to these grasslands are widespread and serious (e.g. climate change, invasive species, fragmentation, altered disturbance regimes, and anthropogenic chemical loads). Because the challenges facing the region are dynamic, complex, and persistent, a paradigm shift in how we approach restoration and management of the grasslands in the NGP is imperative. The goal of this article is to highlight four key points for …

Serological Survey And Pathogen Exposure Of Adult Female White-Tailed Deer In The Western Dakotas, Katherine L. Moratz, Bailey S. Gullikson, Eric S. Michel, Daniel M. Grove, Jonathan A. Jenks, William F. Jensen

Natural Resource Management Faculty Publications

Establishing baseline values for pathogen exposure and nutritional indices is necessary to monitor population health. However, little is known about white-tailed deer (Odocoileus virginianus) pathogen exposure and nutritional condition in the Northern Great Plains. Our objective was to assess pathogen exposure and establish nutritional indices for female white-tailed deer in Dunn and Grant counties, North Dakota and Perkins County, South Dakota. During 2014, we collected blood serum from 150 adult female white-tailed deer. Pathogens with the highest antibody prevalence included West Nile Virus (WNV; 85%), epizootic hemorrhagic disease (48%), and malignant catarrhal fever (32%). Serum values for creatine kinase, globulin, …

Connecting Composting And Greenhouses: An Energy Capture And Usage Model, Dena M. Hoffman

Honors Theses and Capstones

At the Organic Dairy Research Farm in Lee, New Hampshire, the practice of aerated static composting is researched for potential heat capture. In early 2019, an Excel model was created to illustrate the ability of greenhouses to retain heat during a cold month of January and the total energy balance for each day. This model shows that an average greenhouse, based on the dimensions of the greenhouse at Kingman Farm, requires an additional, external heat source to supplement its heating needs. By adding the heat generated by the aerated static composting pile to the greenhouse in the Excel model, the …

Post-Glacial Fire History Of Horsetail Fen And Human-Environment Interactions In The Teanaway Area Of The Eastern Cascades, Washington, Serafina Ferri

All Master's Theses

Landscapes of the Pacific Northwest have been shaped by dramatic shifts in climate since the last glacial maximum and more recently, by human activity. However, it is unclear how past relationships between people, fire, and climate interacted on the landscape. The purpose of this research was to reconstruct the post-glacial fire history of a wetland known as Horsetail Fen, located in the Teanaway area of the eastern Cascades of Washington State. The goal was to evaluate how fire activity has varied under different climatic scenarios during the last ~16,000 years and in relation to human land-use actions. This lake was …

Identifying The Effects Of Land Use And Policy On Disturbance Regimes In The Teanaway Community Forest, Washington, Savannah Bommarito

All Master's Theses

The historic fire regime of the forests of the Eastern Cascades, Washington, has been described as one of high-frequency, low-severity fires using fire scar analysis. Over the past few centuries, the historically open, park-like ponderosa pine-dominated stands have been significantly altered due to Euro-American land use change such as fire exclusion, grazing, mining, and logging. The eventual encroachment of shade-tolerant species has resulted in a high-density forest structure that promotes rare, but extreme fire behavior and heightened susceptibility to insect attacks. As a result, the current disturbance regime is significantly less frequent and of higher severity, posing risks to forest …

Seasonal Soil Carbon Fluxes In Transitioning Agricultural Soils In Central Washington State: Relations To Land-Use, Environmental Factors And Soil Carbon-Nitrogen Characteristics, Brandon Kautzman

All Master's Theses

Changing agricultural land-use practices to increase soil carbon sequestration contributes to climate change mitigation and improved food security by moving CO₂ from the atmosphere into soil as soil organic carbon (SOC). In 2016, a farm in Thorp, Washington, Spoon Full Farm, began converting land historically farmed using conventional methods of tillage and synthetic fertilizers to conservation farming methods with direct seeding and organic soil amendments with a goal of sequestering carbon in the soil. This project evaluates relationships of soil CO₂ respiration and net ecological exchange (NEE) with land-use types, seasonal environmental factors (air temperature, relative humidity, soil …

River Report. State Of The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, Contaminants, 2019, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Gerry Pinto, Brian P. Zoellner, Christopher Baynard, Charles Closmann, Nisse Goldberg, Scott F. Jones, William Penwell, Radha Pyati, Adam E. Rosenblatt, Gretchen Bielmyer-Fraser

State of the River Report

No abstract provided.

Changes In Walleye Fecundity And Egg Size Before, During, And After Rehabilitation Of The Red Lakes Fishery, Benjamin J. Miller, Benjamin D. Erb

Journal of Earth and Life Science

The Red Lakes in northern Minnesota experienced a major Walleye Sander vitreus fishery crash in the late 20th century, but has since recovered to record abundances and supports a major commercial and recreational fishery. Fecundity is an integral aspect of recruitment that can contribute greatly to the understanding of fishery population dynamics. To elucidate the effects of varying Walleye densities and exploitation rates on fecundity and egg size in years 1989 (overexploited fishery), 2004 (recovering fishery), and 2017 (recovered fishery), we analyzed linear models that related fecundity or egg size to morphological features for these three sampling periods. Walleyes were …

Cause‐Specific Mortality Of The World’S Terrestrial Vertebrates, Jacob E. Hill, Travis L. Devault, Jerrold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Aim: Vertebrates are declining worldwide, yet a comprehensive examination of the sources of mortality is lacking. We conducted a global synthesis of terrestrial vertebrate cause‐specific mortality to compare the sources of mortality across taxa and determine predictors of susceptibility to these sources of mortality.

Location: Worldwide.

Time period: 1970–2018.

Major taxa studied: Mammals, birds, reptiles and amphibians.

Methods: We searched for studies that used telemetry to determine the cause of death of terrestrial vertebrates. We determined whether each mortality was caused by anthropogenic or natural sources and further classified mortalities within these two categories (e.g. harvest, vehicle collision and predation). …

Feral Swine Harming Insular Sea Turtle Reproduction: The Origin, Impacts, Behavior And Elimination Of An Invasive Species, Richard M. Engeman, Robert W. Byrd, Jamie Dozier, Mark A. Mcalister, James O. Edens, Elizabeth M. Kierepka, Timothy J. Smyser, Noel Myers

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine are among the world's most destructive invasive species wherever they are found, with translocations figuring prominently in their range expansions. In contrast, sea turtles are beloved species that are listed as threatened or endangered throughout the world and are the focus of intense conservation efforts. Nest predation by feral swine severely harms sea turtle reproduction in many locations around the world. Here we quantify and economically assess feral swine nest predation at North Island, South Carolina, an important loggerhead sea turtle nesting beach. Feral swine depredation of North Island sea turtle nests was first detected in 2005, with …

A Bioeconomic Model For The Optimization Of Local Canine Rabies Control, Aaron Anderson, Johann Kotze, Stephanie A. Shwiff, Brody Hatch, Chris Slootmaker, Anne Conan, Darryn Knobel, Louis H. Nel

United States Department of Agriculture Wildlife Services: Staff Publications

We present a new modeling tool that can be used to maximize the impact of canine rabies management resources that are available at the local level. The model is accessible through a web-based interface that allows for flexibility in the management strategies that can be investigated. Rabies vaccination, sterilization, chemo-contraception, and euthanasia can be specified and limited to specific demographic groups. Additionally, we allowed for considerable complexity in the specification of management costs. In many areas, the costs of contacting additional dogs increases as management effort increases, and this can have important strategic implications. We illustrated the application of the …