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Past, Current, And Future Potential Distributions Of Red Spruce And Fraser Fir Forests In The Southern Appalachians: Interpreting Possible Impacts Of Climate Change, Danika Mosher Dec 2020

Past, Current, And Future Potential Distributions Of Red Spruce And Fraser Fir Forests In The Southern Appalachians: Interpreting Possible Impacts Of Climate Change, Danika Mosher

Electronic Theses and Dissertations

Spruce-Fir forests are relicts from the Pleistocene and can only be found within the Southern Appalachians. Analyzing the relationships between species distribution, climatic parameters, topography, and biotic interactions through ecological niche modeling creates prediction maps for conservation efforts. Maxent, Boosted Regression, and Random Forest were utilized to compare which model and variable combinations best approximate the unique mountain forest environment. Maxent with a bias file produced optimal results and was used to examine distributional changes that may occur in the future and how these changes compare to paleo-environmental distributions. Fraser fir has shown evidence of being influenced by changing climates …


Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel Jul 2020

Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel

LSU Doctoral Dissertations

Floodplain forest species diversity is driven, in part, by variation in disturbance regime. Flood patterns create heterogeneity in microsite quality from small differences in elevation across a floodplain which, in turn, influence flood timing and duration. Differences in species’ regeneration niches in relation to hydrologic patterns can account for long-term coexistence of various species. In the past century floodplain forests have exhibited a wide range of changes in stand development and species composition as a result of altered hydrology in rivers and floodplains. I evaluated the role of regeneration in floodplain forest systems of the Lower Mississippi River Alluvial Valley …


A Framework For Incorporating Benefits From Urban Forests Into Planning For Livable Cities: A Case Study Of Forest Park, Carole Hardy Jul 2020

A Framework For Incorporating Benefits From Urban Forests Into Planning For Livable Cities: A Case Study Of Forest Park, Carole Hardy

Environmental Science and Management Professional Master's Project Reports

Urban forests provide an escape from the noise and chaos of cities. Other services can be overlooked and under-valued. Urban forests cool and filter the air, sequester carbon, filter water removing toxins and sediments from urban runoff, provide habitat for wildlife and improve human health and well-being. Commonly urban forests in the United States (US) lack funds for restoration and research because there is lack of understanding of the need to actively manage what are perceived as wild lands. Generally urban forests are highly disturbed and novel ecosystems that require ongoing active management to remove invasive species, replant native species …


A Comparative Ecological Study Of Limestone And Dolomite Glades In The Ozark Mountains Of Northwest Arkansas, Brittney Booth May 2020

A Comparative Ecological Study Of Limestone And Dolomite Glades In The Ozark Mountains Of Northwest Arkansas, Brittney Booth

Graduate Theses and Dissertations

Glades are one of the many habitats that exist in the Arkansas Ozarks and contribute to the overall biodiversity of the state of Arkansas. For this study, five dolomite glades and five limestone glades in the Ozarks of northwest Arkansas were studied from March to October in the years 2017 and 2018 to determine the similarities or differences that might be present. One hundred and fifteen vascular plant taxa were documented in the dolomite glades and one hundred and three vascular plant taxa were documented in the limestone glades. Forty-six vascular plant taxa were unique to the dolomite glades and …


An Apex Predator In Peril In The Western Lowlands Of Ecuador: Mapping The Population Distribution Of Harpy Eagles (Harpia Harpyja) In A Highly Deforested Region, Samuel Zhang Apr 2020

An Apex Predator In Peril In The Western Lowlands Of Ecuador: Mapping The Population Distribution Of Harpy Eagles (Harpia Harpyja) In A Highly Deforested Region, Samuel Zhang

Independent Study Project (ISP) Collection

The Harpy Eagle (Harpia harpyja) is a highly threatened bird of prey in Ecuador. While they are already elusive in the Ecuadorian Amazon, they are even lesser known in the coastal lowlands, and their existence is threatened by rapid deforestation. This study mapped their potential distribution by examining satellite images to find intact humid forest, their ideal habitat. Habitat areas were quantified using ImageJ. The only sites found to be adequate for sustaining Harpy Eagle populations were the primary forests in the vicinities of Reserva Ecológica Mache Chindul and Reserva Ecológica Cotacachi Cayapas. The two reserves are expected to be …


Long-Term Effects Of Crop-Tree Release On The Growth And Quality Of Upland White Oak Stands, Philip Jay Vogel Jan 2020

Long-Term Effects Of Crop-Tree Release On The Growth And Quality Of Upland White Oak Stands, Philip Jay Vogel

Theses and Dissertations--Forestry and Natural Resources

The alteration of historical disturbance regimes, forest parcelization, and varying goals among landowners all present challenges to oak management in the eastern U.S. Foresters and landowners need tools to promote oak sustainability that are applicable on small forestland holdings and within complex management plans. From this perspective, this research evaluates a crop-tree release study installed in southeastern Kentucky in 1983. The experiment includes four, 2-acre replications of three treatment levels: 20 crop-trees per acre, 34 crop-trees per acre, and a control treatment in which crop-trees were selected but not released. Half-acre measurement plots were installed at the outset of the …


Effects Of Non-Commercial Thinning On Great Horned Owls On Turnbull National Wildlife Refuge, Christopher P. Brady Jan 2020

Effects Of Non-Commercial Thinning On Great Horned Owls On Turnbull National Wildlife Refuge, Christopher P. Brady

EWU Masters Thesis Collection

To sustain forest health, increase species diversity and reduce wildfire events in the ponderosa pine (Pinus ponderosa) forests of at Turnbull National Wildlife Refuge (TNWR) managers have implemented a variety of approaches including prescribed burning and non-commercial thinning. The impacts of thinning on owl species diversity and habitat occupancy have not been studied in these ponderosa pine forests. My study had the following objectives 1) compare forest stand metrics between treatment plots, 2) compare owl species richness between treatment plots, 3) examine if occupancy and detection patterns of Great Horned Owls varied with forest condition and season, respectively, and 4) …


Assessing The Climate Water Balance Model’S Ability To Predict Soil Moisture Variability And Species Distribution Of A Forested Watershed In The Northern Cumberland Plateau, Katherine J. Love Jan 2020

Assessing The Climate Water Balance Model’S Ability To Predict Soil Moisture Variability And Species Distribution Of A Forested Watershed In The Northern Cumberland Plateau, Katherine J. Love

Theses and Dissertations--Forestry and Natural Resources

Spatial patterns of moisture and tree species have been studied using environmental gradients, often represented by terrain attributes in GIS. With climate change, GIS terrain variables, which are static as long as the elevation remains unchanged, will not reflect alterations in temperature, water cycle, and atmospheric conditions. In this thesis, the commonly used terrain variables and climate water balance variables were evaluated and compared for their ability to explain soil moisture and tree species distributions in a forested watershed in the Northern Cumberland Plateau. The results suggest that GIS terrain variables generally perform better than climate water balance variables, however, …


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 …


Plant-Soil Interactions Dominate Soil Microbial Respiration And Soil Organic Carbon Sequestration In A Subtropical Moist Evergreen Broadleaved Forest In China, Zhijie Yang Jan 2020

Plant-Soil Interactions Dominate Soil Microbial Respiration And Soil Organic Carbon Sequestration In A Subtropical Moist Evergreen Broadleaved Forest In China, Zhijie Yang

Theses and Dissertations--Plant and Soil Sciences

Tropical forest soils contain one-third of global soil carbon (C). The warm and moist climate in tropical forests leads to rapid soil organic carbon (SOC) decomposition, with the highest soil microbial respiration rates in the world, so even a slight change in soil C and microbial respiration could affect atmospheric carbon dioxide concentration. However, there remains a lack of understanding of the mechanisms driving microbial respiration in tropical forests, due to different climate and biophysical drivers compared to temperate or boreal forests. Furthermore, forest conversions (from natural forests to plantations) are most widespread in tropical regions, leading to a loss …