Physical Sciences and Mathematics Commons^™

From Sea To Lake: The Depositional History Of Saint Albans Bay, Vt, Usa, Matthew Kraft

Graduate College Dissertations and Theses

Sediment accumulated in lakes stores valuable information about past environments and paleoclimatological conditions. Cores previously obtained from Saint Albans Bay, located in the Northeast Arm of Lake Champlain, VT record the transition from the Champlain Sea to Lake Champlain. Belrose (2015) documented the presence of a peat horizon separating the sediments of the Champlain Sea from those of Lake Champlain. Initially, this layer was thought to comprise the transition from the marine environment of the Champlain Sea to a freshwater wetland. However, based on the results from this study, the transition between marine and freshwater conditions is thought to be …

No Farm Is An Island: Pollinators And Pollination In Agricultural Landscapes, Charles C. Nicholson

Graduate College Dissertations and Theses

Productive, resilient and sustainable agricultural systems are required to meet the immediate needs of a burgeoning human population, while avoiding ecosystem collapse. Agriculture provides food, fiber, fuels and other products for our current population of 7 billion and is still the major livelihood for 40% of people worldwide. By replacing natural habitat and employing chemical inputs, agriculture also negatively impacts biodiversity and impairs the provision of ecosystem services. This poses a challenge for agriculture as these impacted services are often those required for high yielding and high-quality crop production. Evidence is accumulating that agricultural management can safeguard biodiversity and ecosystem …

Conservation Of Ecosystem Services And Biodiversity In Vermont, Usa, Keri B. Watson

Graduate College Dissertations and Theses

Supporting a growing human population while avoiding biodiversity loss is a central challenge towards a sustainable future. Ecosystem services are benefits that people derive from nature. People have drastically altered the earth’s land surface in the pursuit of those ecosystem services that have been ascribed market value, while at the same time eroding biodiversity and non-market ecosystem services. The science required to inform a more balanced vision for land-cover change in the future is rapidly developing, but critical questions remain unanswered regarding how to quantify ecosystem services and ascribe value to them, and how to coordinate efforts to safeguard multiple …

Cargo Transport By Myosin Va Molecular Motors Within Three-Dimensional In Vitro Models Of The Intracellular Actin Cytoskeletal Network, Andrew Thomas Lombardo

Graduate College Dissertations and Theses

Intracellular cargo transport involves the movement of critical cellular components (e.g. vesicles, organelles, mRNA, chromosomes) along cytoskeletal tracks by tiny molecular motors. Myosin Va motors have been demonstrated to play a vital role in the transport of cargos destined for the cell membrane by navigating their cargos through the three-dimensional actin networks of the cell. Transport of cargo through these networks presents many challenges, including directional and physical obstacles which teams of myosin Va-bound to a single cargo must overcome. Specifically, myosin Va motors are presented with numerous actin-actin intersections and dense networks of filaments which can act as a …

Improving Scalability Of Evolutionary Robotics With Reformulation, Anton Bernatskiy

Graduate College Dissertations and Theses

Creating systems that can operate autonomously in complex environments is a challenge for contemporary engineering techniques. Automatic design methods offer a promising alternative, but so far they have not been able to produce agents that outperform manual designs. One such method is evolutionary robotics. It has been shown to be a robust and versatile tool for designing robots to perform simple tasks, but more challenging tasks at present remain out of reach of the method.

In this thesis I discuss and attack some problems underlying the scalability issues associated with the method. I present a new technique for evolving modular …

Genetic And Demographic Consequences Of Lake And River Habitat Fragmentation On Fishes In Vermont, Peter T. Euclide

Graduate College Dissertations and Theses

Globally, habitat fragmentation has had a major impact on the conservation and management of many species and is one of the primary causes of species extinction. Habitat fragmentation is loosely defined as a process in which a continuous habitat is reduced to smaller, disconnected patches as the result of habitat loss, restriction of migration or the construction of barriers to movement. Aquatic systems are particularly vulnerable to habitat fragmentation, and today an estimated 48% of rivers are fragmented worldwide. My dissertation evaluates how habitat fragmentation has influenced the populations of four different species of fish in the Lake Champlain basin. …

Governing Environmental And Economic Flows In Regional Food Systems, Michael Bishop Wironen

Graduate College Dissertations and Theses

Globalization, specialization, and intensification have transformed the global food system, generating material flows and impacts that span multiple scales and levels, presenting novel governance challenges. Many argue for a transition toward a sustainable food system, although the scope and specific goals are fiercely contested. Theory and method is needed to evaluate competing normative claims and build legitimacy.

In this dissertation Vermont serves as a case study to investigate how environmental and economic flows impact regional governance, focusing on efforts to manage agricultural phosphorus to achieve water quality goals. A material flow account is developed to estimate phosphorus flows embedded in …

Ecological Stormwater Management: Analysis Of Design Components To Improve Understanding And Performance Of Stormwater Retention Ponds, Rebecca Tharp

Graduate College Dissertations and Theses

Stormwater runoff from developed land is a source of pollution and excessive flow to waterways. The most commonly employed practices for flow and volume control are stormwater ponds and basins (also referred to as detention and retention ponds). These structures can be effective at controlling peak discharge to water bodies by managing flow timing but are often ineffective at removing nutrients, particularly in dissolved forms. Pond morphology coupled with place-specific characteristics (like soil type and drainage area characteristics) may influence plant community composition in these water bodies. The interaction of physical, chemical, and biological elements in stormwater ponds may affect …

An Autothermal, Representative Scale Test Of Compost Heat Potential Using Geostatistical Analysis, William J. Mccune-Sanders

Graduate College Dissertations and Theses

Composting has been practiced for thousands of years as a way of stabilizing and recycling organic matter into useful soil amendments. Thermophilic compost releases significant amounts of heat at temperatures (~140 °F) that are useful for environmental heating or process water. This heat has been taken advantage of in various ways throughout history, but development of a widely adopted technology remains elusive.

The biggest barrier to adoption of compost heat recovery (CHR) systems is projecting accurate, attractive economic returns. The cost of transfer equipment is significant, and with variability in composting substrates and methods, it is difficult to predict the …