Natural Resources Management and Policy Commons^™

Riparian Buffer Establishment Using Different Management Techniques, Stever H. Bartlett

Graduate College Dissertations and Theses

ABSTRACT

In riparian areas of the northeastern United States, well-established reed canary grass (Phalaris arundinacea) stands are common and have proven to be a challenge for the success of tree plantings during riparian forest restoration projects. The impacts of reed canary grass (RCG) on the habitats it invades are numerous. Reed canary grass reduces biological diversity by homogenizing habitat structure, richness, and environmental variability. Its rapid growth rate and invasive nature limits tree regeneration in riparian forests by shading and crowding out seedlings. Riparian forests improve water quality, wildlife habitat, flood control, and provide a variety of other ecosystem services. …

Forest Management Tradeoffs: Examining Relationships Between Timber Harvest, Carbon Sequestration And Storage, Bioenergy, And Wildlife, Michelle L. Brown

Graduate College Dissertations and Theses

Timber harvesting is the leading cause of adult tree mortality in forests of the northeastern United States. While current rates of harvest are generally sustainable, there is considerable pressure to increase harvest to meet timber production, climate, and energy goals. Maximizing one of these values may compromise other forest resources, including a wide range of ecosystem services and the conservation of native species. This dissertation investigates the effects of timber harvest on carbon sequestration and storage, bioenergy, and wildlife. First, I estimated current harvest regimes for different forest types and regions across the U.S. states of New York, Vermont, New …

Drivers Of Soil Organic Carbon In Rich Northern Hardwood Forests, Sophia Rebecca Marinace

Graduate College Dissertations and Theses

Forests are increasingly being managed for their carbon sequestration potential. As such, an understanding of the factors controlling carbon dynamics across and within sites is becoming increasingly important for guiding carbon management strategies. Given that much of a forest’s carbon is stored in soils, identifying the factors that control how much carbon is stored in soils is critical. This study used detailed vegetation and soil measurements across a rich northern hardwood forest in Corinth, Vermont to identify factors that drive soil carbon storage in a northern hardwood forest, a common type in New England, and investigated how multiple non-native species …

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 …

Imaginaries Of The Great Outdoors: Comparing Facebook Postings Across Resource Places, Frances Hoag

Graduate College Dissertations and Theses

Communication across agencies, interested audiences, and the public is central to resource management. While social media expands agencies’ communication options, it also may present opportunities for constructing and presenting “imaginaries” – collectively imagined discourses that that shape understandings of place and influence the world views of followers. Imaginaries are “socially constructed, taken-for-granted meanings about reality that make everyday social and cultural practices seem obvious and sensible to people” (Stokowski et al., 2021). Extending prior research, we sought to understand whether/how resource management agencies used social media to construct and deploy imaginaries. Data were collected during 2021-2022 from resource management agencies …

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 …

Embracing Uncertainty, Ambiguity, And Complexity In Agriculture, Science, And Policy, Benjamin Timothy Dube

Graduate College Dissertations and Theses

Policy makers say they govern the environment based on scientific evidence, but environmental activists express concern about issues that challenge scientific understandings, such as risk, uncertainty, justice, and participation. This conflict is magnified in agriculture, where many social movements and farmers advocate and create farming systems that are ecological—diverse, heterogenous and adaptive. Ecological farming systems are thus harder for outside experts - researchers, extensionists, development practitioners or policymakers – to understand. Complexity and context-specificity in ecological agriculture presents numerous challenges along the path from scientific inquiry to policy implementation, including in categorizing, systematically studying, modelling and regulating farming systems. In …

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 …

Management For Amphibians In Complex Ecosystems, Lindsey Pekurny

Graduate College Dissertations and Theses

Effective conservation is becoming more difficult as threats to wildlife increase. Natural resource managers are pressured to make difficult decisions with limited resources, and in many instances, some degree of uncertainty. Scientists and managers tasked with the conservation of a species need tools to help guide efficient decision making. Often, information for management decisions is insufficient. Tools that help to inform decision makers and address uncertainty will be invaluable to effective conservation initiatives. Here, we create two models to help managers navigate the complexities associated with decision making. The objective our first study was to create a model to best …

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 …

Modeling Moose Habitat Use And Fitness Consequences Of Habitat Selection In Vermont, Usa, Joshua Alexander Blouin

Graduate College Dissertations and Theses

The moose (Alces alces) population has been declining across the northeastern US largely due to the impacts of winter ticks (Dermacentor albipictus). In epizootic years, an individual moose can host a staggering number of ticks (> 60,000), affecting both survival and reproduction. Habitat management may be used to improve the status of the moose population and health of individuals, but this requires knowledge of key habitat types used by moose and their spatial distribution. We investigated 1) habitat use by moose and 2) the fitness consequences of habitat selection during two critical winter tick life stages in northeastern Vermont. To …

Coastal Resilience At The Nexus Of Food, Energy, And Water: An Interdisciplinary Perspective For Resilience Planning, Kristin Raub

Graduate College Dissertations and Theses

Global climate change poses increased threats to coastal communities. The resilience of coastal communities relies on the protection and continued availability of essential services such as food, energy, and water (FEW) systems. However, the intersection of FEW nexus research and coastal resilience planning has not been well explored. This dissertation seeks to further the goal of operationalizing resilience planning by examining the usefulness of resilience tools and toolkits that have been developed in recent years and exploring how the FEW nexus approach has been applied to coastal resilience planning in both academic and grey literature. The first chapter provides the …

Developing An Adaptive Resource Management Framework For Sustainable Cashmere Production In Mongolia, Elisabeth Lohre

Graduate College Dissertations and Theses

Cashmere is a multi-billion dollar commodity and recent increases in demand have led to the degradation of grassland and desert steppe ecosystems in East and Central Asia. Cashmere wool is a product of goats and 90% of the world’s supply originates from Mongolia and northern China. As global demand for cashmere increases, the consequences to the natural landscapes and people of the region may be severe, especially given the rapid rate of environmental change due to warming climatic conditions in the region.

Textile manufacturers recognize the need for better goat herding practices and support the development of a sustainable cashmere …

The Food-Energy-Water Nexus, Embodied Injustices, And Transboundary Sustainability, Sonya Ahamed

Graduate College Dissertations and Theses

Intersections of food, energy, and water systems (the FEW nexus) pose many sustainability and governance challenges, including risks to ecosystems, inequitable distribution of benefits and harms across populations, and reliance on distant sources for food, energy, and water. Nexus-based approaches can offer more holistic pathways for societal transitions to FEW systems that are just and sustainable, but tend to focus narrowly on inputs (e.g. water ‘for’ energy) in ways that do little to address the historical roots and structural underpinnings of current system inadequacies, thus risking their perpetuation.

This dissertation widens the FEW nexus in two contexts in which the …

Upcycling Dairy Manure Fine Solids Captured By Dissolved Air Flotation As Part Of A Phosphorus Recovery And Reuse Strategy, Katherine Keith Porterfield

Graduate College Dissertations and Theses

Dissolved air flotation (DAF) has shown potential to substantially improve phosphorus (P) mass balance on dairy farms by capturing P associated with fine solids from liquid manure, enabling new management options. However, at < 25% total solids, further dewatering and other upcycling is necessary to facilitate export of recovered fine solids off farm for use in bagged or bulk products. I generated plant foods using DAF-captured dairy manure fine solids thermally dried to 45% total solids blended with other organic residuals. Dry biomass of tomato and marigold seedlings amended with 6% v/v plant food was six-times greater than the unamended control and not significantly different from a market alternative treatment. Because thermal dewatering can be prohibitively costly, I generated a second batch of plant foods using DAF-captured dairy manure fine solids conditioned with 3, 4.5 and 6% (w/w) quicklime or lime kiln dust (LKD) and dewatered using a benchtop press for comparison with thermally dried fine solids. Tomato seedling biomass was similar for thermally dried and LKD plant foods, but quicklime plant foods had no effect compared to the unamended control. Quicklime and LKD conditioned fine solids contained approximately 30 and 10 times less plant-available P than thermally dried fine solids, respectively—likely due to precipitation of Ca-P minerals. These studies indicate that DAF-captured dairy manure fine solids could be upcycled to bagged horticultural products with substantial agronomic value, however sustainable materials drying remains a key challenge to realizing this potential.

Effects Of Winter Ticks And Internal Parasites On Moose Survival And Fecundity In Vermont, Usa, Jacob Richard Debow

Graduate College Dissertations and Theses

Moose (Alces alces) have experienced considerable declines along the periphery of their range in the northeastern United States. In Vermont, the population declined by approximately 44% from 2010 to 2017 despite minimal hunter harvest and adequate habitat. Populations in New Hampshire and Maine have shown similar declines, associated primarily with the impacts of winter ticks (Dermacentor albipictus). However, uncertainty exists about the effects of environmental and other parasite related conditions on moose survival and reproduction. I examined patterns of moose survival and productivity among a radio-collared population (n = 127) in Vermont from 2017 to 2019. In terms of productivity, …

Planning For People In Communities And Outdoor Recreation Places: Fostering Community Cohesion, Shaping Place Meanings, And Exploring Imaginaries, Yumiko Jakobcic

Graduate College Dissertations and Theses

This dissertation examines people’s relationships to place and community. The papers are linked by three broad themes: 1) place meanings, 2) community connections to resource places, and 3) innovative qualitative research methodologies.

The first paper used ethnographic methods in a case study of Vermont’s Winooski Valley Park District to examine how regional park districts can strengthen community relationships. It explored how the district serves visitors and communities, stimulates community interactions and cohesion, and perceives the outcomes of these efforts. Results showed that regional park districts connect people with nature and with others across neighborhoods, communities, and regions. These unique places …

Predicting Wildlife Distributions And Resilience Under Alternative Futures, Schuyler Pearman-Gillman

Graduate College Dissertations and Theses

In the northeastern United States, population expansion, climate change, land use, and land-use change all pose serious concerns for wildlife. Understanding the impacts of climate and land-use change on species distributions can help inform conservation decisions. Unfortunately, empirical data on distributions are limited for many wildlife species, making conservation planning challenging. This dissertation focuses on the use of expert opinion data for modeling wildlife distributions and evaluating the impacts of future climate and land-use changes. First, I implemented expert elicitation techniques to collect wildlife occurrence data for harvested species (n = 10) in the New England region. I then used …

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 …

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 …

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 …

Evaluation Of Mysis Partial Diel Vertical Migration, Brian Patrick O'Malley

Graduate College Dissertations and Theses

Mass animal migrations represent large movements of biomass, energy, and nutrients with predictable patterns and important ecosystem-level consequences. Diel vertical migration (DVM) in aquatic systems, the daily movement of organisms from deeper depths during the day to shallower depths in the water column at night, is widespread in freshwater and marine systems. Recent studies, however, suggest partial migration behavior, whereby only some portion of a population migrates, is the rule rather than the exception in a range of migratory fauna, including those that undergo DVM. Hypotheses to explain why partial migrations occur complicate traditional views on DVM and challenge conventional …

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 …

Applying Bayesian Belief Network To Understand Public Perception On Green Stormwater Infrastructures In Vermont, Qing Ren

Graduate College Dissertations and Theses

Decisions of adopting best management practices made on residential properties play an important role in reduction of nutrient loading from non-point sources into Lake Champlain and other waterbodies in Vermont. In this study, we use Bayesian belief network (BBN) to analyze a 2015 survey dataset about adoption of six types of green infrastructures (GSIs) in Vermont’s residential areas. Learning BBNs from physical probabilities of the variables provides a visually explicit approach to reveal the message delivered by the dataset. Using both unsupervised and supervised machine learning algorithms, we are able to generate networks that connect the variables of interest and …

Land Use, Power, And Knowledge At The Northern Resource Frontier: Mining, Public Engagement, And Contentious Land Imaginaries In Bristol Bay And The Yukon-Kuskokwim Delta, Jonathan Tollefson

Graduate College Dissertations and Theses

The Donlin and Pebbles mines are two of the eight industrial-scale hard rock mines currently under the review of Alaska’s Large Mine Permitting program. Both projects promise to deliver profit and employment to their respective regions: Pebble to Bristol Bay in the southwest, and Donlin to the Yukon-Kuskokwim Delta, just north of Pebble. Both projects would also produce exceptional quantities of waste and will require almost-unprecedented infrastructure development, potentially threatening the lives and subsistence livelihoods of the Alaska Native peoples in their respective regions. The Pebble project inspired international protest and led to the emergence of a powerful resistance coalition …

Cityscape Connections: National Park Service Relevance And Resilience In Urban Areas, Elizabeth Eleanor Perry

Graduate College Dissertations and Theses

The National Park Service (NPS) strives to embody U.S. democratic ideals, conserving our collective stories and scenery for their intrinsic value and the enjoyment of current and future generations. However, although these places are conserved for all, they are not enjoyed by all. As with other conservation agencies, the NPS finds itself increasingly concerned with building relevance with diverse potential stewards. In cities, where 80% of the U.S. population and 40% of the NPS portfolio is based, there is a prime opportunity to build relevance with large, diverse, and proximate audiences. Recognizing this opportunity, the NPS initiated its Urban Agenda …

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 …

Spawning Site Selection And Fry Development Of Invasive Lake Trout In Yellowstone Lake, Yellowstone National Park, Wyoming, Lee Simard

Graduate College Dissertations and Theses

Since their discovery in Yellowstone Lake in 1994, Lake Trout (Salvelinus namaycush) have been the object of an intensive gillnet suppression program due to their predation on native Yellowstone Cutthroat Trout (Oncorhynchus clarkii bouvieri). Managers are also interested in targeting early life stages to augment suppression. A benthic sled was used to sample for Lake Trout eggs at 24 locations, hypothesized to be spawning sites, that encompassed a range of depths, slopes, and substrate composition to determine the location and characteristics of spawning sites in Yellowstone Lake. Lake Trout eggs were collected at seven sites, five of which had not …

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 …

Estimating Landscape Quality And Genetic Structure Of Recovering American Marten Populations In The Northeastern United States, Cody Michael Aylward

Graduate College Dissertations and Theses

The American marten (Martes americana) is an endangered species in Vermont and a Regional Species of Greatest Conservation Need in the northeastern United States. Though historically widespread in northeastern forests, their range presumably contracted to northern Maine and the High Peaks region of the Adirondacks by the early 1900s. Regionally, populations appear to be in recovery. Natural recolonization is believed to have occurred in New Hampshire, northeastern Vermont and the western Adirondacks. A reintroduction effort in southern Vermont that was originally declared unsuccessful is now believed to be the source of a recently detected population in the area. However, our …