Life Sciences Commons^™

Socio-Ecological Economic Impact Analysis Of Food Systems Initiatives Using Mixed Methods And Community-Based Research Approaches, Josiah J. Taylor

Graduate College Dissertations and Theses

Many NGO and government community development programs seek to alleviate complex problems related to food systems and agriculture. Yet, without integrated social, ecological, and economic impact analysis we cannot understand or communicate the value of such interventions. For this research, we partnered with food and agriculture organizations using participatory action research approaches to co-develop and test tools for holistic program analysis. We then used these tools to conduct and co-produce a holistic analysis and evaluation of program impacts. The first chapter provides background and context for the body of the dissertation. Chapter two details work with Hunger Free Vermont to …

Groundwater Governance And Agricultural Sustainability: Examining Farmer Interactions With California’S Sustainable Groundwater Management Act, Zachary Matthew Goldstein

Graduate College Dissertations and Theses

Climate change has exacerbated groundwater depletion globally, and policymakers have struggled to effectively manage groundwater resources. California enacted the Sustainable Groundwater Management Act (SGMA) in 2014 to restore groundwater to sustainable levels.

The first paper of this thesis examines the drivers associated with uptake of groundwater conservation practices in agriculture. While a rich body of research has explored farmers’ conservation practice adoption, understanding of groundwater conservation practices is more limited. This study explores how information sources influence the actual and intended adoption of groundwater management practices in California. Using survey data from farmers (n = 553) in three largely agricultural …

Paleolimnological Data Synthesis To Assess Long-Term Ecological Change In Vermont Lakes, Ismar Biberovic

Graduate College Dissertations and Theses

Lakes are excellent early indicators of environmental change on a landscape scale. Due to their connectedness in the landscape, any alteration of land-cover extends beyond a single watershed and can only be amplified by the effects of climate change. These processes can reflect differently across lakes of various characteristics, however, combined, they can leave a lasting impact on biogeochemical processes of a lake, resulting in profound effects on biological communities residing in it. Lake sediments are terrific archives that integrate and preserve this evidence, which then allows us to investigate the extent to which a lake has changed given its …

Forest Management In The Context Of Global Change: Impacts Of Disturbance, Adaptive Management, And Invasive Species On Northeastern Forests, Jennifer Santoro

Graduate College Dissertations and Theses

Climate change is predicted to have variable and uncertain effects on forested ecosystems globally. In the northeastern US, natural disturbances have historically been a central driver of forest successional dynamics, but as climate warming is projected to alter the frequency and severity of these events, post-disturbance management strategies to sustain biodiversity and ecosystem services must adaptively change to promote forest resilience. A suite of adaptive silvicultural actions has been proposed to promote forest resilience in the face of uncertainty, but due to the multi-decadal scale of forest management, initial field experiments are only beginning to show results. To address these …

Revealing The Direct And Indirect Effects Of Climate Change On Soil Nutrient Dynamics And Forage Resources In Mountain Ecosystems, Kenna Elizabeth Rewcastle

Graduate College Dissertations and Theses

Modern climate change is already altering the structure and function ofecosystems around the world in nontrivial ways. Mountain ecosystems in particular will continue to experience a greater magnitude and rate of climatic warming than the global average, threatening the stability of key ecosystem processes like nutrient cycling as well as the supply of benefits from ecosystem services provided by mountains. While significant advancements have been made to address the direct effects of rising temperatures on nutrient cycling dynamics, our understanding of the synergies between the direct effects of warming and the indirect effects of climate change, mediated by the response …

Implications Of Population Genetics And Physiological Responses On The Conservation Of Moose (Alces Alces Americana), Elias Rosenblatt

Graduate College Dissertations and Theses

Wildlife populations around the globe are facing numerous, complex challengesto their persistence, yet conservation efforts are hindered by limited information about these populations and the anthropogenic pressures they face. North American moose (Alces alces americana), despite being of ecological, cultural, and economical importance, inhabit remote landscapes, making population monitoring difficult. At the same time, many moose populations, including in Vermont and eastern North America, have experienced recent declines mainly due to winter tick (Dermacentor albipictus) epizootics. Anthropogenic landscape change and climate-mediated pressures pose future challenges for moose across the southern extent of their distribution. Though impacts of winter tick infestation …

Changing Environmental Conditions And The Response And Potential Adaptability Of Freshwater Whitefishes, Taylor R. Stewart

Graduate College Dissertations and Theses

Changes in winter conditions, such as increased temperatures and decreased ice coverage, have been observed worldwide. The responses of many lake fish populations to changing winters are projected to be inadequate to counter the speed and magnitude of climate change. Such environmental changes have been hypothesized to explain the low recruitment observed in freshwater whitefishes (Salmonidae Coregoninae). My research focused on measuring the impact changing winter conditions may have on coregonine reproductive phenology and developmental and morphological traits to better predict changes in coregonine populations as a result of climate change.

I used experimental incubation methods and modeling to explore …

Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri

Graduate College Dissertations and Theses

As the ripple-effects of a changing climate shape our planet, understanding relationships between agriculture and climate change is critical. With agricultural practices shaping soils on over a third of the earth’s land surface, the soils and lands where food is produced are integral grounds for examining these relationships. While not all humans practice agriculture in similar or damaging ways, nevertheless, dominant agricultural practices are displacing beings and ecosystems and perturbing global nutrient cycles across the planet. These entwined imbalances of dominance and nutrients result in flows of excess nitrogen, phosphorus, and carbon that are responsible for nearly three-fourths of the …

Spillover, Dilution, And Coinfection: Understanding The Spread Of Disease Within Managed And Native Bee Communities., Phillip A. Burnham

Graduate College Dissertations and Theses

Maintaining healthy pollinator communities is vital both for ensuring food securityand ecological diversity. However, managed honeybees and wild bee communities are under threat from an array of stressors including habitat loss, global change, pesticide use, poor beekeeping, and various pests and pathogens. Pathogens have been shown to be spilling over from managed bees into wild bee populations and are known to adversely affect colony function as well as increase mortality. Understanding transmission mechanisms related to general dynamics in this system will not only benefit pollinator health, but also gives us insight into important and understudied topics in disease ecology. In …

Assessing Chemical And Biological Recovery From Acid Rain Deposition In Montane Vermont Lakes, Sydney Diamond

Graduate College Dissertations and Theses

Vermont’s inland lakes are changing rapidly in response to anthropogenic disturbance pressures. While changes in water chemistry are well documented across the state, the biological response of primary producer communities to these shifts remains poorly understood. This project investigated the response of phytoplankton communities to the interacting effects of recovery from acidification and climate change in high-altitude lakes. We analyzed long-term monitoring and meteorological data in four of Vermont’s acid-impaired lakes and found that as pH and acid-neutralizing capacity has increased, so have concentrations of dissolved organic carbon (DOC) in most lakes. To assess the biological response to these processes, …

Factors Affecting The Adoption Of Automated Wood Pellet Heating Systems In The Northeastern Us And Implications For The Transition To Renewable Energy, Laura Edling

Graduate College Dissertations and Theses

Public and private incentive programs have encouraged conversions to high efficiency, low emissions wood heating systems as a strategy to promote renewable energy and support local economies in the Northeastern US. Despite these efforts, the adoption of these systems remains slow. The study that is the subject of this dissertation examines several social, economic, policy and environmental factors that affect the decisions of individuals and small-scale institutions (local business and community facilities) to transition to automated wood pellet boilers and furnaces (AWPH) utilizing local fuel sources. Due to the complexity and risk associated with conversion, the transition to these systems …

From Tap To Table: Consumer Values, Producer Attitudes, And Vermont Maple Syrup In A Dynamic Landscape, Aidan Conor Mccracken

Graduate College Dissertations and Theses

Harvesting the sap of maple trees [Acer saccharum] for use in the production of syrups and sugars has a storied history stretching back to the pre-Columbian practices of North America’s indigenous peoples. Since its adaptation by European settlers in the late seventeenth century and into the present day, the production of maple syrup has become especially integral to the livelihoods and cultural identities of farmers in Vermont. While oftentimes esteemed as a timeless agrarian tradition, market forces and environmental changes have led maple syrup producers (or sugarmakers) to adopt new production practices that scarcely resemble the taps, buckets, and draft …

Modeling Agricultural Outcomes In A Warmer, Wetter Vermont, Rachel Mason

Graduate College Dissertations and Theses

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 …

Local Farmer Knowledge Of Adaptive Management On Diversified Vegetable And Berry Farms In The Northeastern Us, Alissa White

Graduate College Dissertations and Theses

Agricultural adaptation to climate change is notoriously context specific. Recently updated projections for the Northeastern US forecast increasingly severe and erratic precipitation events which pose significant risks to every sector of agricultural production in the region. Vegetable and berry farmers are among the most vulnerable to the risks of severe precipitation and drought due to the intensive soil and crop management strategies which characterize of this kind of production. To successfully adapt to a changing climate, these farmers need information which is tailored for the unique challenges of vegetable and berry production, framed at the level of climate impacts, and …

Uncovering The Drivers Of Non-Native Plant Invasions Using Ecological Data Synthesis, Marina Golivets

Graduate College Dissertations and Theses

Understanding what promotes invasiveness of species outside their native range and predicting which ecosystems and under which conditions will be invaded is an ultimate goal of the field of invasion ecology. Obtaining general answers to these questions requires synthesis of extensive yet heterogeneous empirical evidence, coupled with a solid theoretical background. In this dissertation, I sought to provide insight into the drivers of non-native plant invasions through combining and synthesizing ecological data from various sources using advanced statistical techniques. The results of this work are presented as three independent research studies.

In the first study, I aimed to understand what …

Physicochemical Properties Of Residuals From Anaerobic Digestion Of Dairy Manure And Food Waste: Nutrient Cycling Implications And Opportunities For Edible Mushroom Cultivation, Brendan J. O'Brien

Graduate College Dissertations and Theses

Organics recycling is increasing in New England as multiple states have enacted laws to divert organic materials, including food scraps and food processing residuals, away from landfills. Anaerobic digesters on dairy farms represent an attractive approach to food waste recycling because existing infrastructure is in place and co-digestion of dairy manure with food waste can increase renewable biogas production. In addition, anaerobic digestion results in effluents that can be separated into solid and liquid residual materials, or 'digestates'. Screw-press separated solids consist of lignocellulosic biomass resistant to microbial degradation during anaerobic digestion. These separated solids are typically recycled on farms …

Consumer Support For Renewable Energy Systems: A Case Study Of Community Biodigesters In Vermont, Katelynn Maria Conedera

Graduate College Dissertations and Theses

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 …

Governing Water Quality Limits In Agricultural Watersheds, Courtney Ryder Hammond Wagner

Graduate College Dissertations and Theses

The diffuse runoff of agricultural nutrients, also called agricultural nonpoint source pollution (NPS), is a widespread threat to freshwater resources. Despite decades of research into the processes of eutrophication and agricultural nutrient management, social, economic, and political barriers have slowed progress towards improving water quality. A critical challenge to managing agricultural NPS pollution is motivating landowners to act against their individual farm production incentives in response to distant ecological impacts. The complexity of governing the social-ecological system requires improved understanding of how policy shapes farmer behavior to improve the state of water quality. This dissertation contributes both theoretically and empirically …

Tools For Landscape-Scale Automated Acoustic Monitoring To Characterize Wildlife Occurrence Dynamics, Cathleen Michelle Balantic

Graduate College Dissertations and Theses

In a world confronting climate change and rapidly shifting land uses, effective methods for monitoring natural resources are critical to support scientifically-informed management decisions. By taking audio recordings of the environment, scientists can acquire presence-absence data to characterize populations of sound-producing wildlife over time and across vast spatial scales. Remote acoustic monitoring presents new challenges, however: monitoring programs are often constrained in the total time they can record, automated detection algorithms typically produce a prohibitive number of detection mistakes, and there is no streamlined framework for moving from raw acoustic data to models of wildlife occurrence dynamics. In partnership with …

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 …

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 …

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. …

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 …

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 …

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 …

Choices And Preferences Of Vermont Master Gardeners - Do Socio-Demographics Matter?, Grace Matiru

Graduate College Dissertations and Theses

ABSTRACT

This study was designed to characterize the choices, preferences and motivations of fruit and vegetable gardeners in Vermont, and to determine whether socio-demographic characteristics affect some of these choices, preferences and motivations. Using a survey of Vermont Extension Master Gardeners (EMGs), data were gathered over a 3-year period (2011-2013). The findings show most EMGs (>90%) garden in private home gardens, and the most popular vegetables grown were tomatoes, herbs, and salad greens. Beans, cucumbers and peppers sere also popular and among fruits, blueberries, apples, raspberries and strawberries were grown by over 40% of EMGs. Approximately 10% of EMG …

Using Multiple Methodologies To Understand Within Species Variability Of Adelges And Pineus (Hemiptera: Sternorrhyncha), Tav Aronowitz

Graduate College Dissertations and Theses

The species of two genera in Insecta: Hemiptera: Adelgidae were investigated through the lenses of genetics, morphology, life cycle and host species. The systematics are unclear due to complex life cycles, including multigenerational polymorphism, host switching and cyclical parthenogenesis. I studied the hemlock adelgids, including the nonnative invasive hemlock woolly adelgid on the east coast of the United States, that are currently viewed as a single species. I used multivariate morphometric analyses to identify morphological differences among hemlock adelgid lineages. With principal component analyses and MANOVA, the six lineages that were used in this study were found to be significantly …

Regeneration Responses To Management For Old-Growth Characteristics In Northern Hardwood-Conifer Forests, Aviva Joy Gottesman

Graduate College Dissertations and Theses

Silviculture practices interact with multiple sources of variability to influence regeneration trends in northern hardwood forests. There is uncertainty whether low-intensity selection harvesting techniques will result in desirable tree regeneration. Our research is part of a long-term study that tests the hypothesis that a silvicultural approach called "structural complexity enhancement" (SCE) can promote accelerated development of late-successional forest structure and functions. Our objective is to understand the regeneration dynamics following three uneven-aged forestry treatments modified to increase postharvest structural retention: single-tree selection, group selection, and SCE. In terms of regeneration densities and composition, how do light availability, competition, seedbad, and …

Early Feeding In Lake Trout Fry (Salvelinus Namaycush) As A Mechanism For Ameliorating Thiamine Deficiency Complex, Carrie L. Kozel

Graduate College Dissertations and Theses

Recruitment failure of lake trout (Salvelinus namaycush) in the Great Lakes has been attributed in part to the consumption of alewife (Alosa pseudoharengus) by adult lake trout, leading to Thiamine Deficiency Complex (TDC) and early mortality in fry. The current understanding of thiamine deficiency in lake trout fry is based on information from culture and hatchery settings, which do not represent conditions fry experience in the wild and may influence the occurrence of TDC. In the wild, lake trout fry have access to zooplankton immediately following hatching; previous studies found that wild fry begin feeding before complete yolk-sac absorption. However, …

Lasting Legacies Of Hurricane, Harvesting, And Salvage Logging Disturbance On Succession And Structural Development In An Old-Growth Tsuga Canadensis-Pinus Strobus Forest, Emma Sass

Graduate College Dissertations and Theses

Disturbance events affect forest composition and structure across a range of spatial and temporal scales, and forest development may differ after natural, anthropogenic, or compound disturbances. Following large, natural disturbances, salvage logging is a common yet controversial management practice around the globe. While the short-term impacts of salvage logging have been studied in many systems, the long-term effects remain unclear. Further, while natural disturbances create many persistent and unique microsite conditions, little is known about the long-term influence of microsites on forest development. We capitalized on over eighty years of data on stand development following the 1938 hurricane in New …