Thesis (M.M.E.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-01

Near Burlington, Vermont, the Champlain Thrust fault placed massive Cambrian dolostones over calcareous shales of Ordovician age during the Ordovician Taconic Orogeny. Although the Champlain Thrust has been studied previously throughout the Champlain Valley, the architecture and structural evolution of its fault zone have never been systematically defined. To document these fault zone characteristics, a detailed structural analysis of multiple outcrops was completed along a 51 km transect between South Hero and Ferrisburgh, Vermont. The Champlain Thrust fault zone is predominately within the footwall and preserves at least four distinct events that are heterogeneous is both style and slip direction. The oldest stage of structures—stage 1—are bedding parallel thrust faults that record a slip direction of top-to-the-W and generated localized fault propagation folds of bedding and discontinuous cleavages. This stage defines the protolith zone and has a maximum upper boundary of 205 meters below the Champlain Thrust fault surface. Stage 2 structures define the damage zone and form two sets of subsidiary faults form thrust duplexes that truncate older recumbent folds of bedding planes and early bedding-parallel thrusts. Slickenlines along stage 2 faults record a change in slip direction from top-to-the-W to top-to-the-NW. The damage zone is ~197 meters thick with its upper boundary marking the lower boundary of the fault core. The core, which is ~8 meters thick, is marked by the appearance of mylonite, phyllitic shales, fault gouge, fault breccia, and cataclastic lined faults. In addition, stage 3 sheath folds of bedding and cleavage are preserved as well as tight folds of stage 2 faults. Stage 3 faults include thrusts that record slip as top-to-the-NW and -SW and coeval normal faults that record slip as top-to-the-N and -S. The Champlain Thrust surface is the youngest event as it cuts all previous structures, and records fault reactivation with any top-to-the-W slip direction and a later top-to-the-S slip. Axes of mullions on this surface trend to the SE and do not parallel slickenlines. The Champlain Thrust fault zone evolved asymmetrically across its principal slip surface through the process of strain localization and fault reactivation. Strain localization is characterized by the changes in relative age, motion direction along faults, and style of structures preserved within the fault zone. Reactivation of the Champlain Thrust surface and the corresponding change in slip direction was due to the influence of pre-existing structures at depth. This study defines the architecture of the Champlain Thrust fault zone and documents the importance of comparing the structural architecture of the fault zone core, damage zone, and protolith to determine the comprehensive fault zone evolution.

Earning a college degree has been shown to have a number of positive socioeconomic impacts on individuals and society as a whole. Although researchers acknowledge that the decision to attend college is a complex process involving multiple factors, studies have focused primarily on individual reasons as part of a linear college choice paradigm. Individual obstacles to college attendance that consistently emerge in this strand of research include academic preparation, socioeconomic status, cost, family background, parental influence, motivation, and guidance counselor support (Harris & Halpin, 2002). College attendance rates are particularly low among students living in rural areas. Nationwide, only 59 percent of students from rural America choose to attend college, compared to 62 percent of their urban counterparts and 67 percent of students from suburban areas. (National Student Clearinghouse, 2015). The purpose of this study was to examine the college decision-making process of high school students in rural Vermont to better understand why fewer than 61 percent choose to attend college, despite more than 90 percent aspiring to do so at some point during their K-12 academic career (VSAC, 2016). A qualitative ethnographic case study approach was used to provide a unique student-focused perspective on the complexities of the college-decision making process as they go through it during their senior year of high school. A series of in-depth interviews were conducted with 10 students at two rural high schools throughout their senior year as they wrestled with an influx of information from multiple sources creating a series of pushes and pulls from guidance counselors, family members and friends with varying motives. Individual case study analyses were conducted on the following three groups of students based on their level of commitment to attend college at the start of their senior year: College Confident, College Considering and College Conflicted. A cross-case analysis of those three groups was also conducted. The result is a detailed account of how students in each group internalized and acted upon new information about their post-secondary plans, which depended heavily on when they received it, who they received it from and its quality. In most cases, the experience proved to be a frustrating, convoluted process that waxed and waned with each new piece of information. Ultimately, students made final college-going decisions based heavily on a combination of information that was not always accurate, sometimes misleading, and on the advice of at least one parent they perceived as having their best interest in mind.

The Prospect Rock Fault (PRF) is key to our understanding of the regional tectonic evolution of Vermont during the Taconic, Salinic, and Acadian Orogenies, and may have played an important role in the exhumation of blueschist and eclogite-facies rocks in the Tillotson Peak Complex (TPC) during the Taconic Orogeny. The TPC is in the footwall of the PRF in the eastern limb of the Green Mountain Anticlinorium. In the TPC, the dominant foliation is S2 and E-W trending F2 folds parallel L2 stretching lineations, which trend orthogonal to regional N-S trending folds associated with the Taconic Orogeny. The PRF itself is folded by F2 folds. Presently, there is a lack of consensus about the role of the PRF in the exhumation of the TPC, and studies have not reconciled the formation of the E-W folds and lineations to a regional model. Oriented samples and structural data were collected from the footwall of the PRF over several transects. Samples were processed into orthogonal thin sections for microstructural analyses and for 40Ar/39Ar step heating of white mica. The dominant foliations in the PRF samples were identified through microstructural analysis and correlating the age of deformation as S2 and S3. These were defined in thin section by mica and quartz microlithons, and oriented mica grains. S1, and in some samples S2, are locally preserved in some mica domains and albite/garnet inclusion trails. S4 appears as crenulations of S3, with no significant new mineral crystallization. In the field, L2 and L3 lineations are defined by mineral and quartz rods, and L4 lineations are defined as intersection lineations on S2 surfaces. 40Ar/39Ar analyses yielded plateau ages ranging from 458.6 ± 2.0 Ma to 419.0 ± 2.4 Ma (1σ). The oldest plateau ages are just slightly younger, yet concordant, with published and new 40Ar/39Ar ages from the TPC and come from the structurally highest portions of the footwall in the northern part of the study area. Virtually all apparent age spectra show age gradients. Results from this study suggest the PRF played a role in exhumation of the TPC and ages obtained are closely aligned with deformation ages constrained from 40Ar/39Ar dating in southern Quebec for the Taconic D2 and Salinian D3 deformation. These dates may aid correlatation of ages and structures regionally and further refining of tectonostratigraphic models describing southern Quebec and New England.

This thesis aimed to model agricultural outcomes that are important to Vermont dairy farms and their surrounding communities -- runoff, erosion, nitrogen and phosphorus losses, crop yields, and timeliness of farm operations -- under a set of possible future climates. The Agricultural Policy/Environmental eXtender (APEX) model was used for this work, and the models were calibrated using data from a project that measured most of these outcomes on a set of local farms. The model setup and calibration methodology is thoroughly documented and may be a useful starting point for others who are new to agricultural modeling. Applied to two farms growing continuous corn, the future climate simulations showed that increasing temperatures by 2 C, combined with raising total precipitation or changing the seasonality of precipitation, had little effect on any outcome. Intense rainfall has increased greatly in recent decades, so a combination of higher temperatures and more intense precipitation was also simulated. This led to more runoff, more soil loss, and more nutrient losses. While median values were only modestly increased, the 95%-ile and total losses over the simulation period increased by a larger amount (as much as 53%, depending on the site). Management practices that can reduce runoff and soil/nutrient loss exist, but their effectiveness when a higher fraction of losses occur in large events is not well known. Crop yields changed by <10% in all simulations, and in some cases increased slightly. Other studies have warned of decreases in yields because of high summer temperatures and droughts. The pilot simulations in this thesis probed only a limited range of climate parameter space, so running the models for a wider range of scenarios may illuminate the circumstances in which particularly harmful and beneficial outcomes occur. Finally, APEX can in principle calculate the delays to corn planting that are expected if climate change leads to wetter conditions in the spring. However, the models consistently predicted that only harvest operations will be delayed. The reasons for this are not well understood, and it may be a useful avenue for future work. The present work is limited in a number of ways. Chief among these are somewhat mediocre model performance, and the narrow range of farming systems and climate scenarios investigated. Statistics describing the performance of the calibrated models were poorer than anticipated, and satisfactory results could not be obtained for some nutrient loss pathways. Only two farms were modeled, in just four hypothetical future climates; results for other relevant farming systems and climates may be quite different. Nonetheless, it is hoped that this thesis serves as a useful illustration of the potential and limitations of utilizing the APEX model in this context, and that it lays the groundwork for a more extensive investigation of agricultural outcomes under climate change in Vermont.

From the steady rise in dairy farm closures to concerns over algae blooms in Lake Champlain, Vermont’s dairy industry is facing a multitude of challenges. While many potential solutions have been proposed, this study focuses specifically on community anaerobic digester systems (CADS) to aid in manure management, help to mitigate runoff, produce renew energy, and even provide an alternative revenue source to participating farms. CADS technology converts the gas emissions from manure and other organic substances into biogas through a process called anaerobic digestion. Unlike traditional on-farm biodigesters, which are often only financially viable for the largest dairy farms, CADS are able to accept both manure from multiple dairy farms and food waste from the surrounding community. In Vermont, consumers can purchase biogas-produced electricity from biodigesters in the state for an additional cost through Green Mountain Power’s Cow Power program. However, little research has been conducted regarding the success of CADS-produced electricity on the consumer market. This thesis focuses on two surveys conducted in Randolph, Vermont and Addison County exploring attitudes of local biodigesters in relation to other renewable energy sources available to consumers, as well as issues related to composting and recycling. The objective of this study is to provide policy makers and biodigester operators a better understanding of community attitudes of biodigesters compared to other renewable energy systems, as well as willingness to participate in paid services that could support the operation of the biodigesters. In 2017, a survey was distributed to households in Randolph, the location of the Vermont Technical College CADS, through the local newspaper. A second survey was also conducted in 2019, distributed via newspaper to residents in Addison County, a dairy county home to four operational biodigesters. Results from the 2017 survey suggest that there is generally a low willingness to pay for the Cow Power program and food waste removal services that support biodigesters, although targeted educational approaches focusing on how CADS benefit the community may improve attitudes towards them. The 2019 survey shows similar levels of willingness to participate and pay, although attitudes of biodigesters and public support for anaerobic digester technology were considerably higher. Through educational outreach efforts, community acceptance of biodigesters can be improved to avoid cancellation of projects due to lack of community support.

Global environmental change represents one of the greatest challenges facing forest resource managers today. The uncertainty and variability of potential future impacts related to shifting climatic and disturbance regimes on forest systems has led resource managers to seek out alternative management approaches to sustain the long-term delivery of forest ecosystem services. To this end, forest managers have begun incorporating adaptation strategies into resource planning and are increasingly utilizing the outcomes of forest landscape simulation and climate envelope models to guide decisions regarding potential strategies to employ. These tools can be used alongside traditional methods to assist managers in understanding the potential long-term effects of management and climate on future forest composition and productivity. This study used a spatially explicit forest landscape simulation model, Landis-II, to examine and evaluate a range of long-term effects of current and alternative forest management under three projected climate scenarios within a 50,000-hectare forested landscape in southeastern Vermont, USA. Multiple scenarios were examined within this mixed ownership landscape, allowing for an evaluation of the influence of management and climate on future forest conditions in the region. These simulations indicate that land-use legacies and the inertia associated with long-term forest successional trajectories are projected to be an important driver of future forest composition and biomass conditions for the next 100 years. Nevertheless, climate is projected to have a greater influence on species composition and aboveground biomass over the next two centuries, with forests containing a greater abundance of species from more southerly regions and lower levels of aboveground biomass, resulting in shifts in the future provisioning of ecosystem services. Key words: Vermont, USA; climate change; forests; LANDIS-II; forest adaptation; forest management; above ground biomass; landscape inertia; land use recovery; forest composition

Suburban encroachment is a growing concern for many National Guard training installations. The Ethan Allen. Firing Range and Camp Johnson, Vermont, are either experiencing or are completely enclosed by urban encroachment. The objective of this study was to analyze the trends of suburban growth within Chittenden County, Vermont, to evaluate growth and explore future training site viability of the Ethan Allen Firing Range and Camp Johnson. This study focused on historical data, recent real estate transactions, population projections, and county plans for growth. Using historical and contemporary data, I developed a predictive model of suburban encroachment on Camp Johnson and the Ethan Allen firing Range facilities by residential and commercial development. This model may assist land managers make decisions and illustrate the viability of these installations as National Guard training sites. This model may also be applied to other installations with similar concerns.

Due to its high levels of concern and awareness of environmental issues, rural character, and sparse population, Vermont would at first glance appear to possess the ideal recipe to become a national leader in renewable energy development. Renewable initiatives have focused primarily on wind energy, as over a dozen wind farms have been proposed in the last few years across the state. However, in spite of the widely held belief in Vermont’s wind energy future, its proponents have run into vehement opposition at every proposed site, often successfully impeding the planned developments. This report develops a wide-level framework of the motivations of and complaints presented by wind opposition groups around the state, followed by an analysis of opposition strategies commonly employed. These are contrasted with the tactics used by wind developers and their supporters to remediate or overcome this opposition. Next, this essay will offer a view of the state and local institutional settings in which these battles take place, and finally conclude with a brief analysis of various alternatives to utility-scale wind, offering suggestions for wind’s role in the future of energy in Vermont.

Wind Energy facilities are becoming a more common occurrence among the U.S. landscape. The shift to renewable from non-renewable energy sources is an important agenda item for energy policy in the 21st century. Unlike other forms of energy, the unique visual aspects of wind energy provide opportunities to engage with and actually view the process of energy production. The sculptural element of turbines and their placement in highly visible areas, such as mountain ridges, provides opportunities of environmental interpretation and public interaction. Although existing security and safety precautions in the U.S. do not allow public use of these facilities, the integration of turbines into public places is becoming more common in other parts of the world. This creative project focuses on developing dynamic and unique cultural places that also serve as education spaces to celebrate wind and wind energy. Environmental art installations among the wind turbines serve as human-scaled interpretational guides to create meaningful, learning experiences between the user, the wind and the landscape.This project highlights the existing eleven-turbine (6MW) facility in the town of Searsburg in southern Vermont. This project includes inventory, analysis and site design of an existing wind facility. The methodology includes using GIS data and existing sight line data, as well as significant and environmental cultural points. Finally, general guidelines are included as a design foundation for other wind energy facilities. / Department of Landscape Architecture