Physical Sciences and Mathematics Commons^™

An Analysis Of Gulf Of Maine Cod Metapopulation Structure And Localized Stability, With Application To Area-Based Fisheries Management, Derek Olson

Electronic Theses and Dissertations

The complex metapopulation structure of groundfish stocks in the Gulf of Maine, particularly Atlantic cod (Gadus morhua), is largely ignored under the current system of broad-scale stock assessment and management. This mismatch of biological and administrative scales has contributed to severe overall stock decline and localized serial depletion of Gulf of Maine cod. Such chronic management failure has led to growing calls for a more area-based, finer-scale approach to managing groundfish in the Gulf of Maine. A primary difficulty hindering the development of finer-scale groundfish management has been the challenge of estimating fishing mortality upon local stock components. …

Willingness To Pay For Irrigation Water Under Scarcity Conditions, Tyler Robert Knapp

Graduate Theses and Dissertations

Reliance of Arkansas agricultural producers on groundwater for irrigation has led to depletion of the Mississippi River Valley alluvial aquifer. Without intervention, consequences include insufficient groundwater to meet irrigation demand as well as drawdown of the deeper Sparta Aquifer, upon which communities in eastern Arkansas rely for non-agricultural use. Among proposed solutions to combat groundwater decline is the construction of off-farm surface water infrastructure to meet the irrigation needs of producers. Despite the importance of irrigated agriculture to Arkansas, there is little know about the economic value of irrigation water to producers. Thus, we implement a double-bounded dichotomous choice contingent …

Surface Water Infiltration In Loess Soils Of The Lower Mississippi River Valley: An Emphasis On Land Use, Matthew Thompson

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The Alluvial Aquifer is the shallowest and most heavily used groundwater aquifer in the Lower Mississippi River Valley, particularly in the Delta region of eastern Arkansas. However, the Alluvial Aquifer is being depleted faster than the rate of recharge, primarily due to excessive withdrawals for irrigated crop production. Since extensive irrigation in the highly agriculturally productive Delta region of eastern Arkansas has been a main culprit in the groundwater depletion issues the region faces, a better understanding of how ecological factors and/or agricultural best management practices could possibly increase infiltration, to consequently increase recharge, are needed in order to either …

Modern Fair-Weather And Storm Sediment Transport Around Ship Island, Mississippi: Implications For Coastal Habitats And Restoration Efforts, Eve Rettew Eisemann

Master's Theses

The Mississippi – Alabama barrier island chain is experiencing accelerated sea level rise, decreased sediment supply, and frequent hurricane impacts. These three factors drive unprecedented rates of morphology change and ecosystem reduction. All islands in the chain have experienced land loss on the order of hectares per year since records began in the 1840s. In 1969, Hurricane Camille impacted as a Category 5, breaching Ship Island, and significantly reduced viable seagrass habitat. Hurricane Katrina impacted as a Category 3 in 2005, further widening Camille Cut. To better understand the sustainability of these important islands and the ecosystems they support, sediment …

Assessing Tennessee Landowners' Attitudes Toward Wild Hogs And Support For Control Options, Carlotta Anne Caplenor

Masters Theses

Wild hogs (Sus scrofa) are an invasive species with destructive habits, particularly rooting and wallowing, which can directly impact agricultural crops, pasture land, and water quality. Considering wild hogs are widely dispersed across the landscape, it is extremely difficult to control them. Moreover, disagreements can arise among different stakeholders over whether and how their population should be managed. The purpose of this study was to examine Tennessee landowners’ attitudes toward wild hogs, to compare acceptability of control methods, and to evaluate the factors significantly influencing public support for wild hog control regulations. Logistic regression was used to analyze …

Understanding Stakeholder Attitudes And Involvement In Habitat Conservation Plans And The Endangered Species Act, Kyle Andrew Rodgers

Masters Theses

The Endangered Species Act (ESA), established in 1973, was a landmark piece of environmental legislation and remains the standard for endangered species conservation. Implementation of the ESA has often been framed as pitting economic development against species conservation, inciting passions for and against endangered species conservation. The strength of opposing public opinions is highlighted by high-profile controversies such as those around the snail darter, northern spotted owl and the greater sage grouse. In an attempt to reduce conflict, the US Fish and Wildlife Service (USFWS) increasingly seeks to utilize collaborative, stakeholder-based processes that address stakeholder interests, attitudes, and values.

In …

Stochastic Network Design: Models And Scalable Algorithms, Xiaojian Wu

Doctoral Dissertations

Many natural and social phenomena occur in networks. Examples include the spread of information, ideas, and opinions through a social network, the propagation of an infectious disease among people, and the spread of species within an interconnected habitat network. The ability to modify a phenomenon towards some desired outcomes has widely recognized benefits to our society and the economy. The outcome of a phenomenon is largely determined by the topology or properties of its underlying network. A decision maker can take management actions to modify a network and, therefore, change the outcome of the phenomenon. A management action is an …

An Ecosystem-Based Approach To Reef Fish Management In The Gulf Of Mexico, Michelle D. Masi

USF Tampa Graduate Theses and Dissertations

Fisheries managers have the potential to significantly improve reef fish management in the Gulf of Mexico through the use of ecosystem-based approaches to fisheries management. Ecosystem-based approaches are needed to address the effects of fishing on trophodynamic interactions, to better account for ecosystem-scale processes in model projections, and to recognize the short and long-term biomass tradeoffs associated with making regulatory choices. My research was concentrated around three objectives: (1) characterizing the trophodynamic interactions between Gulf of Mexico fishes, in order to construct an invaluable tool (a Gulf of Mexico Atlantis model) to be used in ecological hypothesis testing and policy …

Ecological Consequences Of Lost Anadromous Forage Fish In Freshwater Ecosystems, Steven R. Mattocks

Masters Theses

Beginning in the early 1600s, dam construction in New England obstructed anadromous fish access to spawning grounds during migration. As a result, anadromous forage fish populations have declined, which has impacted freshwater, marine, and terrestrial ecosystems. To determine the impacts of dams on anadromous forage fish and freshwater ecosystems, I used historical and current data to estimate population changes in alewives (Alosa pseudoharengus) from 1600-1900. A significant reduction in spawning habitat occurred in New England as a result of 1,642 dams constructed between 1600 and 1900, resulting in 14.8% and 16.6% lake and stream habitat remaining by 1900, …

Factors Affecting Habitat Quality For Wintering Wood Thrushes In A Coffee Growing Region In Honduras, Brett A. Bailey

Masters Theses

Amongst the diversity of taxa that occur in the Neotropics, 200 migratory bird species that breed in temperate North America can be found. Many of these populations have seen significant declines since the 1960s. The Wood Thrush, Hylocichla mustelina, is one such species. Shade coffee and other agroforestry practices show potential for benefiting migratory species, but the quality of coffee habitat and optimal habitat characteristics for Wood Thrushes remain unknown.

I surveyed a spatially complex, agricultural landscape in Honduras outside the recognized winter range of the Wood Thrush and radio-tagged 46 individuals within rustic coffee farms during the winters …

Channel Form And Processes In A Formerly Glaciated Terrain, Nathaniel Bergman

Electronic Thesis and Dissertation Repository

Despite that many places around the world in general, and North America in particular, were glaciated during the last ice age, relatively little is known about rivers that evolved over these landscapes once they deglaciated. These rivers are commonly categorized as alluvial with a glacial legacy, and often described as plain gravel-bed or sand-bed rivers. Alternatively, they are considered to be bedrock rivers when the glacial deposits were eroded and underlying rock was exposed. However, ignoring the glacial history of these rivers is scientifically wrong and they should be termed "semi-alluvial". This work shows that classification is important, not only …

A Habitat Analysis Of Estuarine Fishes And Invertebrates, With Observations On The Effects Of Habitat-Factor Resolution, Brianna Michaud

USF Tampa Graduate Theses and Dissertations

Between 1988 and 2014, otter trawls, seine nets, and plankton nets were deployed along the salinity gradients of 18 estuaries by the University of South Florida and the Florida Fish and Wildlife Research Institute (FWRI, a research branch of the Florida Fish and Wildlife Conservation Commission). The purpose of these surveys was to document the responses of aquatic estuarine biota to variation in the quantity and quality of freshwater inflows that were being managed by the Southwest Florida Water Management District (SWFWMD).

In the present analyses, four community types collected by these gears were compared with a diversity of habitat …

Takeover On The Tallgrass Prairie: How Lespedeza Cuneata Establishes Dominance, Morgan Rae Walder

Theses and Dissertations

Invasion ecology aims to study mechanisms by which invasive species are able to enter, establish, and spread within an ecosystem. This study analyzed Darwin’s naturalization and the biotic resistance hypotheses as the most likely explanations for invasion by an exotic legume, Lespedeza cuneata, into a tallgrass prairie. Darwin’s naturalization hypothesis posits that exotic species are less able to establish in communities that have related species, because similarity in morphology and function promotes intense competition for resources. The biotic resistance hypothesis states that competitors, herbivores, and pathogens already present in the community limit the colonization, naturalization, and persistence of invaders, therefore …

Uncertainty Analysis Of The Performance Of A System Of Best Management Practices For Achieving Phosphorus Load Reduction To Surface Waters, Jason D.M. Igras

Electronic Thesis and Dissertation Repository

The repeated occurrence of Lake Erie’s harmful algal blooms suggests an inadequate phosphorus management system that results in excessive loads to the lake. In response, Canadian and United States’ governments have issued a new management objective, a 40% reduction in total and dissolved reactive phosphorus loads relative to 2008. To provide scientific evidence to guide managers toward achieving their management objective, we used the International Organization of Standardization (ISO) 31010 Bowtie Risk Analysis Tool to analyze the performance of the phosphorus management system. The effectiveness of agricultural best management practices (BMPs) and their adoption were combined into a Bayesian belief …

Effects Of Surrounding Water Table On A Forested Wetland Habitat In East Coast Of Virginia, Lane Stokes

Civil & Environmental Engineering Theses & Dissertations

Exchanges into and out of a wetland, including surface water flow, groundwater flow, and constituents in the flows, usually determine the wetland physicochemical characteristics and biodiversity. To date, of these three exchanges, groundwater flow is the least studied, particularly in the United States of America. In this thesis, field observations were conducted at a forested non-tidal wetland, located on a flat hilltop. The position of the wetland is such that groundwater outflow is the only significant exchange that could be impacted by the surrounding land use. In addition, a spatially variable steady-state model was set up to extrapolate the observations …

Social Ecological Food Systems: Sustainability Lessons From Maine Dairy Networks, Julia B. Mcguire

Electronic Theses and Dissertations

Milk production has played an integral role in the culture, landscape, and economy of Maine’s agriculture. Maine dairy farmers have faced numerous sustainability challenges to economic, environmental, and social aspects of their industry. Like many other complex social ecological systems, the Maine dairy industry faces a gap between scientific knowledge and actionable management or policy. A cultural dichotomy exists between conventional and organic farming. Shifting the focus from this binary, metrics such as social capital may play a key role in solving sustainability issues. Difficulties arise in the governance of complex social ecological systems when the scales of assessment, management, …

How Do Connection And Hopeful Action Support Resilient Community?, Catherine Gormley

Capstone Collection

This capstone arises from the course, Initiatives in Peacebuilding (IPB). As a graduate student focusing on Peacebuilding and Conflict Transformation, IPB was a required course whose content propelled me toward the study of resource conflicts. Advancing from that study, I chose to practice strategies to lessen these conflicts by means of positive action. Facing two challenges—that Earth’s natural resources are finite and that excessive use of fossil fuels has caused destructive climate change—I wondered how to help transform human awareness to value the conservation of resources and the abatement of climate change. My research brought me to Joanna Macy, an …

Assessing The Remanufacturability Of Office Furiniture: A Multi-Criteria Decision Making Approach, Po-Hsun Chen

Theses and Dissertations

While the average life cycle of consumer goods is continuously decreasing, the amount of used product at their end-of-life (EOL) is accumulating fast at and at the same pace. Most EOL products end up in landfills, and many of which are not biodegradable. These two challenges have necessitated renewed global interest in product EOL management strategies by manufacturers, third party companies, consumers and governments. Remanufacturing is one of the EOL strategies which is highly environmental-friendly. Additionally, remanufacturing is seen as one of the highly profitable re-use business strategies. The selling price of remanufactured products is usually about 50—80% of a …

Water Source Partitioning For Shrubland Transpiration In A Mixed Phreatophytic Plant Community, Amanda Jean Wagner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater in the basins of east central Nevada (Great Basin Desert, NV) has been permitted for export to southern Nevada. These basins are also vulnerable to changes in climate that could lead to declining recharge. Any decline in groundwater levels no matter the driving force could significantly impact phreatophytes (deep rooted shrubs), which utilize water from both the vadose zone and the capillary fringe to meet plant water needs, to support growth, and for overall health. A reduction in groundwater due to these forces could have a significant impact on the decoupling of phreatophytes from what is normally a reliable …

A Comparative Sustainability Study For Treatment Of Domestic Wastewater: Conventional Concrete And Steel Technology Vs. Vegetated Sand Beds (Vsb’S) And Their Relative Differences In Co2 Production, Alicia M. Milch

Masters Theses

Conventional wastewater treatment in the U.S. is an energy dependent and carbon dioxide emitting process. Typical mechanical systems consume copious amounts of energy, which is most commonly produced from fossil fuel combustion that results in the production of CO₂. The associated organic load is also metabolized by microorganisms into CO₂ and H₂O. As the desire to reduce CO₂ output becomes more prominent, it is logical to assess the costs of conventional treatment methods and to compare them to alternative, more sustainable technology. Vegetated Sand Bed (VSB) and Reed Bed (RB) systems are green technologies …

North American Butterfly Association Counts At Congaree National Park: A Case Study For Connecting Citizen Science To Management, Austin Clarridge

Theses and Dissertations

Citizen science is becoming an ever more popular way for scientists and resource managers to deal with needs for large temporal and spatial scale datasets. It provides a free or low cost means for collection of extensive amounts of data across time and space while acting as a public education and outreach tool, empowering communities to be involved in the management decisions being made in their back yard. Though large, well-known citizen science programs such as the Christmas Bird Counts are being used extensively for peer reviewed literature and management decisions, there are numerous smaller, local counts that have the …

A Comparison Of Framing In Two Environmental Conflicts, Alexander M. Iannone

Theses and Dissertations

Frames can be perspectives about people, objects, events, or settings that guide action based on past experiences and values. Conflicts are created by different stakeholders “holding conflicting frames.” Researchers in the past have used framing analysis to try and better understand environmental conflicts that tend to perpetuate for extended periods of time. A set of researchers have relied on specific framing categories and typologies as a framework for analysis. They have found that the strong presence or lack thereof certain frames can tell us a lot about conflict dynamics and shed light into the undercurrents driving the complexity of the …

Automated Household Tracking System, James Triola

Honors Theses

The past few years have seen the highest recorded amount of waste produced in America. Despite several options of responsible wasting, landfills are still bearing the brunt of waste deposits. Although recycling is a common practice, it is still not accomplished with maximum efficiency, and composting is even less common in areas where it is not legally mandated. Food scraps and byproducts that could otherwise have been broken down in proper composting methods continue to pile up in landfills where they breakdown into methane gas. Although there is no easy answer to the complex problem that is consumer waste, the …

Northern San Francisco Bay Ecological Risk Assessment: Potential Crude By Rail Incident, Meagan Bowis

Master's Projects and Capstones

Oil spill models, ecological risks, response options, and costs were assessed for a discharge of Bakken crude oil into the Northern San Francisco Bay from a train derailment. This assessment was based on the risk of crude by rail derailments into the San Francisco Bay; in 2014, California oil refineries imported over 240 million gallons of Bakken crude oil by rail for processing. A hypothetical scenario was developed from a derailment on the Union Pacific Railroad Bridge and discharging 100,000 gallons of Bakken crude oil into the Northern San Francisco Bay. The oil trajectory impacted the Carquinez Strait, Suisun, San …

Impacts To Anadromous Fish Through Groundwater Extraction, Aaron Hebert

Master's Projects and Capstones

California uses more groundwater than any other state in the United States in order to meet agricultural demand during the growing season when water is naturally least available due to the state’s Mediterranean climate. The state also hosts populations of anadromous fish that are otherwise found exclusively in the wetter Pacific northwest. Groundwater has historically helped maintain baseflow in the summer and fall low-flow periods and acted as a natural buffer against the regular droughts that occur in California. Today, groundwater provides 30-40% of the state’s water supply, but the pumping in many cases has reduced groundwater discharge and baseflow, …

Evaluation Of Alternative Strategies To Prevent Leopard Predation On Livestock Around Yala National Park, Sri Lanka, Sanjiv Fernando

International Development, Community and Environment (IDCE)

In recent years, many livestock herders living near Yala National Park, Sri Lanka have reported livestock losses due to predation by leopards (Panthera pardus kotiya). Despite herders’ attempts to safeguard their cattle, livestock depredation remains an issue, sometimes causing herders to kill leopards in retaliation. In an effort to mitigate the human-leopard conflict, protective cattle enclosures made from steel pipes and mesh wire were introduced to prevent leopard attacks on cattle. This study aims to assess the severity of leopard predation on livestock, understand the methods used in retaliatory killings, examine the effectiveness of existing livestock protection methods, …

Development Of A Decision Support System For Post Mining Land Use On Abandoned Surface Coal Mines In Appalachia, Matthew Zimmerman

International Development, Community and Environment (IDCE)

Decision support systems are diverse and have been used to solve multiple problems ranging from the complex to the simple. With the complexity of environmental decisions today, these systems provide a logic based approach to evaluating and choosing environmental solutions. Abandoned mining lands (AML) are an issue for the environment in the Appalachian region. Given this a decision support system was designed using previously created frameworks and indices from other systems created. The system is comprised of two main sections, selecting the ideal post-mining land-use (PMLU), and maximizing the potential of land to be reclaimed under budgetary constraints. This system …

Initial Wetland Hydrology And Vegetation Composition In Predicted Wetlands Adjacent To Lake Naconiche, Nacogdoches County, Texas, Amy L. Urbanovsky

Electronic Theses and Dissertations

Plans for the construction of Lake Naconiche, located in northern Nacogdoches County, included a monitoring project to demonstrate at least 176 acres of land adjacent to the lake would be converted into wetlands. The purpose of the study was to evaluate the creation of wetlands around the lake and establish a benchmark of vegetation composition and condition for future comparison. Eight locations, placed where the majority of wetlands were expected to form, were chosen for monitoring from the shoreline at 348 feet above mean sea level (ft MSL) to the county fee take line at 357 ft MSL.

Shallow groundwater …

Intraspecific Variation In The Response Of Elymus Elymoides To Competition From Bromus Tectorum, Rebecca K. Mann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the western United States, thousands of acres of degraded rangelands are dominated by aggressive invasive species such as cheatgrass (Bromus tectorum), and are seeded by managers with native plants in an attempt to restore species diversity, wildlife habitat, and ecosystem services. There are many options for obtaining seeds of native plants; for instance, they can be collected from the region where restoration is to occur, or they may be purchased through commercial producers. For a given plant species, managers may also select seeds from unique subspecies, cultivars, and populations. Genetic differentiation among these within-species groups can not only affect …

Nitrogen And Phosphorus Enrichment Effects On Nutrient Supply In Reservoirs: A Small-Scale Approach, Jessalyn G. Kohn

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Eutrophication is a problem in many lakes, but the reduction of nutrient inputs such as nitrogen (N) and phosphorus (P) to combat eutrophication can lead to an oligotrophic state, which may be unable to support healthy aquatic ecosystems. This study examined how different rates of chemical fertilization with N and P during times of nutrient limitation (mid-summer) could affect particulate N and C concentrations in four lakes in northwest Arkansas. Fertilization experiments were conducted in microcosms during the month of July 2014. Water samples from each lake were collected and divided into six treatments: control, P-only, N:P 10, 20, 40, …