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Demand For Guided Tours On The Tennessee River., Gessika Lee Guerra Dec 2023

Demand For Guided Tours On The Tennessee River., Gessika Lee Guerra

Masters Theses

Knoxville, TN is a major urban center in east Tennessee. Knoxville’s urban planners recognized the need for green space and have installed free greenways and parks within the downtown area over several decades. These attractions are immensely popular and promote urban ecotourism. There is an opportunity to begin or expand guided tour services. This research will analyze the demand and willingness to pay for guided river activities – kayaking and pontoon boating – on the Tennessee River in downtown Knoxville. Primary data were collected by 1000 on site flyers connected to an online survey platform. These data were uploaded into …


Variability In Microclimate And Carbon Dynamics In Hardwood Forests Managed With The Irregular Shelterwood Reproduction Method, Melody June Mount Dec 2023

Variability In Microclimate And Carbon Dynamics In Hardwood Forests Managed With The Irregular Shelterwood Reproduction Method, Melody June Mount

Masters Theses

How do forest edges compare to intact interior forests in terms of carbon dynamics, and how is the microclimate altered through the creation of forest edges? Woody plants and trees can act as a carbon sink by using live and dead tissue to store varying amounts of carbon. However, factors such as age, species, respiration rates, and death alter the amount of carbon sequestered by the forest (Gorte, 2009). Additionally, widespread forest fragmentation has resulted in 20% of forests worldwide being located within 100 meters (m) of a forest edge (Haddad et al., 2015). Despite this fragmentation, current carbon models …


The Discovery Of A Novel Bacteria From A Large Co-Assembly Of Metagenomes, Matthew Finkelberg Nov 2023

The Discovery Of A Novel Bacteria From A Large Co-Assembly Of Metagenomes, Matthew Finkelberg

Masters Theses

In the summer of 2022, a co-assembly of metagenome was created using the microbes found at Barres Woods in Harvard Forest. 14 samples were taken, and sample was split into the organic and mineral layer, which totals 28 Bulk MAGs. Within this Co-assembly, 4 different genomes were found which were designated with the phylum of FCPU426. Three of which were considered medium quality and one being assigned high quality. The novel phyla first appeared in NCBI and GTDB databases in June 2018. The name FCPU426 dates to 2010 and was named based on the 16s amplicon sequencing.

The novel phylum …


Climate Change Attitudes Of United States Family Forest Owners And Their Influence On Forest Management Practices, Logan Miller Nov 2023

Climate Change Attitudes Of United States Family Forest Owners And Their Influence On Forest Management Practices, Logan Miller

Masters Theses

Understanding family forest owners’ (FFOs’) attitudes and behaviors towards climate change will allow for more sustainable forest management practices to be implemented, helping to combat climate change and its impacts. The goals for this research are (1) to begin measuring U.S. FFO attitudes toward climate change, (2) to determine what factors impact these attitudes, and (3) to determine how they influence the FFO’s management practices using the Responsible Environmental Behavior (REB) framework (Hines et al. 1987). Chapter 1 explores the different facets of my thesis project focusing on forests and forests’ ecosystem services, forest ownership in the United States, and …


Advancing Natural White Oak (Quercus Alba.) Reproduction Through A Midstory Removal, Canaan Jeffrey Dugger Aug 2023

Advancing Natural White Oak (Quercus Alba.) Reproduction Through A Midstory Removal, Canaan Jeffrey Dugger

Masters Theses

In recent decades, there has been an alarming decline in white oak (Quercus alba.) regeneration and recruitment occurring within eastern forests. Historically, the frequency and the intensity of anthropogenic disturbances was dynamic over the landscape. However, over just the last century a major compositional shift has occurred from this change in disturbance regimes. Eastern forests are now promoting the regeneration of mesic species that obstruct white oaks’ ability to compete successfully and establish in the upper canopy.

The majority of successful white oak regeneration and recruitment is now occurring on the average to more xeric sites. Limited studies …


A Watershed Prioritization Model For Community-Centered Riparian Forest Restoration In Tennessee, Madison Johnson Aug 2023

A Watershed Prioritization Model For Community-Centered Riparian Forest Restoration In Tennessee, Madison Johnson

Masters Theses

Riparian forests are unique ecosystems that act as transitional areas between land and water that are a vital part of a healthy and functional stream ecosystem. Due to the rapidly changing landscape, riparian forests are increasingly threatened by urban development, agriculture, and invasive species, which contributes to a trend of degrading water quality in Tennessee. To address declining riparian forest quality in the face of land-use changes, the purpose of this study was to develop a simple watershed prioritization model that identifies areas that are highly susceptible to poor water quality, and where riparian plantings would be most beneficial. This …


Exploring Alternative Methodologies To Estimate By-Species Sawlog Volume In The Southeastern United States, Tara Skiba May 2023

Exploring Alternative Methodologies To Estimate By-Species Sawlog Volume In The Southeastern United States, Tara Skiba

Masters Theses

The Forest Inventory and Analysis (FIA) conducts Timber Products Output (TPO) studies to assess timber resource use across the United States. The TPO studies gather information through surveys of primary wood processing facilities to quantify the utilization of roundwood by geographic location, tree species, and timber product type. However, not all responding mills provide information on tree species utilized. As a result, a portion of the reported volume falls into the “unknown/unclassified” softwood or hardwood category, which account for up to 74% of total hardwood/softwood southern volumes in some cases. In addition, the detailed species in the TPO survey forms …


The Relative Effects Of Functional Diversity And Structural Complexity On Carbon Dynamics In Late-Successional, Northeastern Mixed Hardwood Forests, Samantha Myers Apr 2023

The Relative Effects Of Functional Diversity And Structural Complexity On Carbon Dynamics In Late-Successional, Northeastern Mixed Hardwood Forests, Samantha Myers

Masters Theses

Late-successional forests provide a unique opportunity to explore adaptive management approaches that mitigate atmospheric carbon dioxide levels through carbon storage while also enhancing ecological resilience to novel climate and disturbances. Typical benchmarks for adaptive forest management include species diversity and structural complexity, which are widely considered to increase ecosystem stability and productivity. However, the role of functional trait diversity (e.g., variation in leaf and stem traits) in driving forest productivity and ecosystem resilience remains underexplored. We leveraged existing continuous forest inventory (CFI) data and collected local functional trait observations from CFI plots within late-successional forests in western Massachusetts to explore …


Effects Of Prescribed Fire On Planted Oak Growth And Survival In Restored Savannas, Allison Earl Jan 2023

Effects Of Prescribed Fire On Planted Oak Growth And Survival In Restored Savannas, Allison Earl

Masters Theses

Most oak savannas in the Midwestern United States have been lost to agriculture and habitat degradation. Because of their rarity and ability to support high plant and animal diversity, savannas are often a target for restoration. Oak savanna restoration frequently relies on direct planting of oak seedlings to establish the necessary tree canopy. Returning fire to the system is critical to the herbaceous component of the savanna, but managers risk damaging or killing trees if burning is introduced too soon. I studied growth and physiological responses of three oak species (Quercus alba, Q. macrocarpa, and Q. velutina …


Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh Aug 2022

Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh

Masters Theses

The Congo Basin Forest harbors a rich diversity of epiphytic communities, with the Orchidaceae alone making up more than 50% of all epiphytes in the region. Despite the huge diversity of epiphytes, many species, including epiphytic orchids, are at risk to a diverse array of threats. Climate change for instance poses severe threats to epiphytic orchids due to elevated temperatures, prolonged periods of droughts, as well as reduced rainfall across the Congo Basin Forest. In this study, we used ecological niche modeling and GIS techniques to identify spatial patterns of species richness, potential future climate refugia, and novel climatic suitability …


Assessment Of The Economic And Ecosystem Service Contributions Of Usda Forest Service Landowner Assistance Programs In The Conterminous United States, Jacqueline S. Dias Mar 2022

Assessment Of The Economic And Ecosystem Service Contributions Of Usda Forest Service Landowner Assistance Programs In The Conterminous United States, Jacqueline S. Dias

Masters Theses

Forests provide immense goods and services to both local and regional communities. The USDA Forest Service’s, State and Private Forestry program administer multiple landowner assistance programs aimed at helping private forest owners while supporting the continued supply of ecosystem services (e.g., timber harvesting, recreation, carbon sequestration and storage). The two landowner assistance programs assessed in this study are the Forest Legacy Program (FLP) and the Forest Stewardship Program (FSP). A majority of the nation’s forests are privately owned, many of which are facing deleterious impacts like wildfires, invasive species, development pressures, and other adverse effects from climate change. The goal …


Growth, Browsing And Mortality In Mixed Oak And Pine Plantings, Heather Slayton Dec 2021

Growth, Browsing And Mortality In Mixed Oak And Pine Plantings, Heather Slayton

Masters Theses

The purpose of this project was to determine if different oak/pine arrangements elicited potential beneficial interactions that affected seedling growth, mortality and overall protection from deer browsing. Northern red oak (Quercus rubra L.) and shortleaf pine (Pinus echinata Mill.) were planted together and alone in six different planting patterns and spacings, replicated over three blocks in recent clearcuts in east Tennessee, USA. Each block consisted of two monocultures planted at a 3.0 by 3.0 meter (m) spacing and four multi-cropped treatments planted at varying spatial arrangements (0.3 m, 1.0 m, 1.5 m, and 3.0 m) from neighboring shortleaf …


Assessing The Structure And Function Of Utility Forests In Massachusetts, Ryan Suttle Oct 2021

Assessing The Structure And Function Of Utility Forests In Massachusetts, Ryan Suttle

Masters Theses

Trees in a community provide numerous benefits, including reducing ambient temperature, removing gaseous and particulate pollutants from the air, sequestering atmospheric carbon, and improving stormwater retention and filtration. However, trees also pose risks, especially in proximity to overhead utility lines. Trees near utility lines cause a large proportion of electrical power outages. As such, trees must be frequently and often severely pruned away from lines to minimize this risk. Presumably, community trees not growing near overhead utility lines are not pruned as frequently or severely. The objectives of this study are to (i) assess factors related to both individual trees …


The Efficacy Of Habitat Conservation Assistance Programs For Family Forest Owners In Vermont, Margaret E. Harrington Oct 2021

The Efficacy Of Habitat Conservation Assistance Programs For Family Forest Owners In Vermont, Margaret E. Harrington

Masters Theses

The future of Vermont’s 1.8 million hectares (4.5 million acres) of forest habitat will be largely determined by the decisions of family forest owners, who collectively own 60% of the state’s forested land. To promote management for wildlife habitat, government agencies and non-governmental partnerships provide technical and financial support to family forest owners in the form of conservation assistance programs. In Chapter 1, I qualitatively compared the efficacy of two types of conservation assistance programs available in Vermont: traditional programs offered through the Natural Resources Conservation Service, and a simplified, accelerated program offered through a non-governmental partnership called Woods, Wildlife, …


Can Volunteers Learn To Prune Trees?, Ryan W. Fawcett Oct 2021

Can Volunteers Learn To Prune Trees?, Ryan W. Fawcett

Masters Theses

Volunteer pruning programs are becoming an important tool in helping municipal arborists manage the urban forest. To find if volunteers can learn to prune trees well, the ability of volunteers to prune small trees after receiving training was assessed in three different ways, a written exam, a pruning prescription assessment, and a pruning cut assessment. Volunteers were assigned to either an indoor, lecture-based training or an outdoor, hands-on training session. After the training volunteers were asked to complete a written exam to gauge their understanding of the curriculum. Volunteers were then asked to perform a pruning prescription on small street …


Eyield: Testing The Adoption And Outcomes Of A Novel Online Growth And Yield Model, Timothy S. Kane Aug 2021

Eyield: Testing The Adoption And Outcomes Of A Novel Online Growth And Yield Model, Timothy S. Kane

Masters Theses

eYield is an online growth and yield platform designed to assist landowners and land managers in making the best choices for their properties. eYield aims to strike a balance between the necessary data to run growth and yield models while remaining accessible to its landowner userbase. The results of this paper point to an encouraging amount of user interest in computer-aided forestry tools, specifically in growth and yield models like eYield. The pre- and post-surveys of eYield from respondents suggest that there is a yearning for tools like eYield and that eYield is reasonably representative of the real world. These …


Lidar Evaluation Of The Structural Complexity Of Multi-Cropped White Oak (Quercus Alba) And Pine (Pinus Spp.) Plantings In East Tennessee, Usa, Bret Alan Elgersma Aug 2021

Lidar Evaluation Of The Structural Complexity Of Multi-Cropped White Oak (Quercus Alba) And Pine (Pinus Spp.) Plantings In East Tennessee, Usa, Bret Alan Elgersma

Masters Theses

Structural complexity has an important influence on wildlife habitat and several other ecosystem services. Establishment of white oak (Quercus alba) intercropped with loblolly pine (Pinus taeda), shortleaf pine (Pinus echinata), or eastern white pine (Pinus strobus), in 2014 provided the opportunity to investigate effects of planting species mixtures in different spatial arrangements on structural complexity. Terrestrial LiDAR was used to evaluate the structure of each intercropped treatment and monoculture control. The measures of complexity included: 1) rumple 2) top rugosity 3) standard deviation of individual tree crown area, 4) standard deviation of …


Controlling Woody Vegetation For The Underplanting And Reintegration Of Shortleaf Pine Into Upland Hardwood Forests Of The Southeast, Max Street May 2021

Controlling Woody Vegetation For The Underplanting And Reintegration Of Shortleaf Pine Into Upland Hardwood Forests Of The Southeast, Max Street

Masters Theses

Shortleaf pine (Pinus echinata Mill.) has the widest distribution of any pine species in the southeastern United States. Shortleaf pine is an important softwood commercial timber species, second only to loblolly pine (Pinus taeda). The amount of shortleaf pine has diminished dramatically beginning in the early 19th century.

The decline of shortleaf pine has been attributed to several, primarily societal factors. Old field abandonment has declined which provided optimum seed bed conditions for the establishment of shortleaf pine. The timber industry began to favor the faster-growing loblolly pine with shorter stand rotations at the expense of …


Regenerative Effects Of Patch Cut Harvests At Natchez Trace State Forest, Joshua K. Biggerstaff May 2021

Regenerative Effects Of Patch Cut Harvests At Natchez Trace State Forest, Joshua K. Biggerstaff

Masters Theses

Patch cutting is a harvest method with very little precedent in the Central Hardwoods Region of the United States. It is defined as a small scale clearcut of 2 to 5-acres, and it is generally prescribed in order to lessen the aesthetic impact of harvesting in highly visible areas. This study examines a change in harvesting from clearcutting to patch cutting that occurred at Natchez Trace State Forest, located in west Tennessee, in the 1990s. The objective of the study was to determine the regenerative effects of the patch cuts 25-30 years later. Various patch-cut harvest units that were harvested …


From Drones To Soil Cores: Comprehensive Ecological Assessments For Enhancing Conservation Management Of Urban Forested Natural Areas, Mia T. Wavrek Dec 2020

From Drones To Soil Cores: Comprehensive Ecological Assessments For Enhancing Conservation Management Of Urban Forested Natural Areas, Mia T. Wavrek

Masters Theses

Urban natural areas are vegetated areas within cities that exhibit characteristics of non-urban natural areas in that they have relatively high levels of self-regulation (low or no level of management) of natural ecosystem processes and exhibit high taxonomic, genetic, and structural diversity. When these areas take the form of urban parkland, they are often managed for their social benefits to urban residents, while their ecological potential remains underutilized. Growing interest in enhancing biodiversity conservation in cities has highlighted the importance of improving the ecological planning and management of urban natural areas, particularly forested natural areas. For the variety of agencies …


Conservation Of Terrestrial Salamanders Through Hemlock Woolly Adelgid Management In Eastern Hemlock Forests Within Great Smoky Mountains National Park, Jonathan Lawrence Cox Dec 2020

Conservation Of Terrestrial Salamanders Through Hemlock Woolly Adelgid Management In Eastern Hemlock Forests Within Great Smoky Mountains National Park, Jonathan Lawrence Cox

Masters Theses

Hemlock woolly adelgid (Adelges tsugae; HWA), an invasive aphid-like arthropod, was first documented on the east coast of the United States in the 1950s. HWA is an herbivore which primarily feeds at the needle base of hemlock tree species (Pinaceae: Tsuga). With no evolutionary defenses and few biotic controls, the eastern and Carolina hemlock (Tsuga canadensis and Tsuga carolinensis) serve as the primary diet of HWA in eastern North America. The invasive pest began to spread rapidly throughout the hemlock’s range causing defoliation and death of the trees within 4 – 10 years. With the …


Carbon Sequestration In A Restored West Michigan Oak Savanna: Implications For Management Practices, Jeffrey A. Heise Aug 2020

Carbon Sequestration In A Restored West Michigan Oak Savanna: Implications For Management Practices, Jeffrey A. Heise

Masters Theses

The savanna system is an ecosystem (i.e. a transitional ecosystem) that lies between forest and grassland ecosystems. They occur across the world in various forms, but in the North American Midwest they are specifically oak savannas: systems where the open overstory is dominated by various species of oak (Quercus spp.) and the understory consists of carbon-rich prairie grasses and forbs. This ecosystem is a highly degraded ecosystem and has lost almost 99% of its former range due to agriculture and fire suppression. Since savannas are fire-evolved systems, they are maintained by and require fire as a regular disturbance to …


The Ecological Value Of Spruce Plantations In Massachusetts, Calvin Ritter Jul 2020

The Ecological Value Of Spruce Plantations In Massachusetts, Calvin Ritter

Masters Theses

The establishment of monoculture plantations of exotic tree species is common practice for supplementing native timber stocks. Such plantations typically provide inferior habitat for wildlife compared to native forest, which may result in a net reduction in biodiversity. However, some studies report that plantations may increase net biodiversity at the landscape scale by introducing novel habitats or supplementing existing natural forests. Using point count surveys, I examined six mature Norway spruce (Picea abies) plantations in western Massachusetts in 2016 and 2017 to evaluate bird use of these habitats relative to native forest stands. Count data were analyzed using …


Cellulose Based Separator For High-Performance Lithium-Ion Batteries, Akshit Vaidya Apr 2020

Cellulose Based Separator For High-Performance Lithium-Ion Batteries, Akshit Vaidya

Masters Theses

During the past two decades, lithium-ion batteries (LIBs) have gained great success in the field of portable devices, and currently, are penetrating to the market of vehicles. Compared to the fast development of LIBs, little efforts have been dedicated to the separator, which is one of the most important components of LIBs. Primarily, the lithium-ion battery separator has two functions, one is to prevent direct contact between the positive and negative electrodes, and the other is to provide a path for effective ionic transportation. Currently, the separator market of LIBs is dominated by polyolefin materials such as polypropylene, polyethylene, and …


Is Context Dependency Imperative To Understanding The Impacts Of Invasive Plants?, Brendan B. Haile Jan 2020

Is Context Dependency Imperative To Understanding The Impacts Of Invasive Plants?, Brendan B. Haile

Masters Theses

Introduced exotic species have a tendency to become invasive and impact local biological communities. Invasions often impact community attributes such as cover and species richness, but these factors may also regulate patterns of invasion. In such cases, impacts may be dependent on the invasion context. We used data from the Buell-Small Succession Study, a long-term permanent plot study in the piedmont region of New Jersey, to document context dependency in invasion. To do this, we analyzed the factors that affected the colonization and growth of four invasive species, Alliaria petiolata, Lonicera japonica, Microstegium vimineum and Rosa multiflora, as well …


Arboriculture Safety Around The World, Jamie Lim Oct 2019

Arboriculture Safety Around The World, Jamie Lim

Masters Theses

Arboricultural work is inherently dangerous, with more serious injuries and fatalities than most other professions. Safety standards exist in some jurisdictions, but it is unclear how many standards exist, how they compare to one another, and whether (and how many) jurisdictions share standards. To establish a baseline understanding of these issues, my objectives were to (i) develop a database of existing standards, (ii) identify the most frequently occurring safety topics and (iii) describe similarities and differences in safety topics among standards from different countries. I worked with a variety of contacts and traditional university library resources to identify, obtain, analyze, …


Ecological Considerations And Application Of Urban Tree Selection In Massachusetts, Ashley Mcelhinney Jul 2019

Ecological Considerations And Application Of Urban Tree Selection In Massachusetts, Ashley Mcelhinney

Masters Theses

Trees provide countless environmental, economic, and societal benefits to the urban environment, and may become increasingly important to maintaining environmental quality and human well-being in the face of increasing urbanization and climate change. However, trees in these urban areas are rapidly diminishing across the United States. Much of this loss can be prevented with proper planning and management, focused on selecting tree species that are both well-suited to the area’s growing conditions and able to survive the many stress factors in an urban setting. Choosing which tree species to plant in Massachusetts is especially challenging considering the lack of resources …


Garlic Mustard (Alliaria Petiolata) Management Effectiveness And Plant Community Response, Erin Coates-Connor Jul 2019

Garlic Mustard (Alliaria Petiolata) Management Effectiveness And Plant Community Response, Erin Coates-Connor

Masters Theses

The control and eradication of the invasive biennial herb garlic mustard (Alliaria petiolata) and the restoration of invaded forest habitats present important linked challenges to land managers in North America. Removing garlic mustard by hand and by glyphosate herbicide application have both been used as eradication strategies with mixed results. Each method has advantages and disadvantages, but they are rarely compared for effectiveness and community impact across multiple years of management. Some previous studies have shown improvements in species diversity and plant community composition following management, while others have found no differences. To better understand both garlic mustard …


Ecological And Economic Implications Of Establishing Quercus Spp. In The Urban Environment, Tierney Bocsi Jul 2019

Ecological And Economic Implications Of Establishing Quercus Spp. In The Urban Environment, Tierney Bocsi

Masters Theses

As urban greening efforts continue, it is important to assess whether decisions to intensify street tree planting are meeting intended goals of improving urban canopy cover and increasing ecosystem services. Benefits of the urban forest take many forms, from ecological and economic to social and cultural, and are frequently cited in support of street tree planting. However, it is unknown to what extent factors such as species or nursery production method affect the ability of trees to successfully establish and provide ecosystem services in the urban environment. Using a system of oak trees planted along roads in South Amherst, Massachusetts …


Impacts Of Plant-Microbe Interactions On Seedling Performance In A Riparian Forest Invaded By Lonicera Maackii, Taylor E. K. Strehl Jan 2019

Impacts Of Plant-Microbe Interactions On Seedling Performance In A Riparian Forest Invaded By Lonicera Maackii, Taylor E. K. Strehl

Masters Theses

Soil microbes have profound impacts on plant growth and survival and can either promote or inhibit plant dominance. Exotic plants are often strongly invasive because they have escaped their natural enemies, potentially including antagonistic soil microbes. I examined how the invasive shrub Lonicera maackii and a common native tree, Acer negundo, responded to soil microbial communities to determine the role of soil microbes in regulating invasion success. This was done by growing both species with microbes from invaded (L. maackii) and uninvaded (A. negundo) soils collected from three locations within a riparian forest. Seedlings were …