Life Sciences Commons^™

Exploring Soil Microbial Dynamics In Southern Appalachian Forests: A Systems Biology Approach To Prescribed Fire Impacts, Saad Abd Ar Rafie

Doctoral Dissertations

Prescribed fires in Southern Appalachian forests are vital in ecosystem management and wildfire risk mitigation. However, understanding the intricate dynamics between these fires, soil microbial communities, and overall ecosystem health remains challenging. This dissertation addresses this knowledge gap by exploring selected aspects of this complex relationship across three interconnected chapters.

The first chapter investigates the immediate effects of prescribed fires on soil microbial communities. It reveals subtle shifts in porewater chemistry and significant increases in microbial species richness. These findings offer valuable insights into the interplay between soil properties and microbial responses during the early stages following a prescribed fire. …

Characterization Of Lignin Structural Variability And The Associated Application In Genome Wide Association Studies, Nathan D. Bryant

Doctoral Dissertations

Poplar (Populus sp.) is a promising biofuel feedstock due to advantageous features such as fast growth, the ability to grow on marginal land, and relatively low lignin content. However, there is tremendous variability associated with the composition of biomass. Understanding this variability, especially in lignin, is crucial to developing and implementing financially viable, integrated biorefineries. Although lignin is typically described as being comprised of three primary monolignols (syringyl, guaiacyl, p-hydroxyphenyl), it is a highly irregular biopolymer that can incorporate non-canonical monolignols. It is also connected by a variety of interunit linkages, adding to its complexity. Secondary cell wall …

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 …

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 …

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

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 …

Multidimensional Investigation Of Tennessee’S Urban Forest, Jillian L. Gorrell

Doctoral Dissertations

Preserving existing trees in urban areas and properly cultivating urban forest conservation and management opportunities is valuable to the ever-growing urban environment and necessary for creating optimal experiences and educational tools to meet the needs of increasing urban populations. This dissertation contains studies investigating several facets of the urban forest, including environmental effects of deforestation and urbanization, tree equity, and urban forest facility management and accessibility. Community education and outreach at arboreta about the importance of the tree canopy can help promote environmental stewardship. A digital questionnaire was electronically distributed to representatives of arboreta certified through the Tennessee Division of …

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 …