Physical Sciences and Mathematics Commons^™

Variation In Personality Among Semi-Wild Myanmar Timber Elephants, Sateesh Venkatesh

Theses and Dissertations

This study examines two personality traits: exploration and neophobia, which could influence human-elephant conflicts. Thirty-one semi-wild elephants were tested over two trials using a custom novel puzzle tube containing three tasks and three rewards. Our studies show that elephants do vary significantly between individuals in both exploration and neophobia.

Projected Impact Of Mid-21st Century Climate Change On Wildfire Hazard In A Major Urban Watershed Outside Portland, Oregon Usa, Andy Mcevoy, Max Nielsen-Pincus, Andres Holz, Arielle J. Catalano, Kelly E. Gleason

Environmental Science and Management Faculty Publications and Presentations

Characterizing wildfire regimes where wildfires are uncommon is challenged by a lack of empirical information. Moreover, climate change is projected to lead to increasingly frequent wildfires and additional annual area burned in forests historically characterized by long fire return intervals. Western Oregon and Washington, USA (westside) have experienced few large wildfires (fires greater than 100 hectares) the past century and are characterized to infrequent large fires with return intervals greater than 500 years. We evaluated impacts of climate change on wildfire hazard in a major urban watershed outside Portland, OR, USA. We simulated wildfire occurrence and fire regime characteristics under …

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 …

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 …

Assessment Of Factors Influencing Migratory Landbird Use Of Forested Stopover Sites Along The Delmarva Peninsula During Autumn Migration, J. Andrew Arnold

Biological Sciences Theses & Dissertations

Autumn migration is a time when billions of birds move from breeding grounds in North America to wintering grounds in Central and South America, with many individuals relying on stopover habitats en route for resting and refueling purposes. These stopover sites are critical to the survival of the hundreds of species of migratory landbirds that migrate annually, and thus identifying important stopover sites is a high priority for conserving such taxa. The Delmarva Peninsula; a coastal region of Delaware, Maryland, and Virginia along the mid-Atlantic flyway; consists of forested habitats with ample food and shelter that likely serves as quality …

Hot But Not Dry: Modest Changes In Water Relations For An Epiphytic Bromeliad In A Tropical Dry Deciduous Forest, Saúl Hernández-Robinson, Eric A. Graham, Olivia Hernández-González, Roberth Us-Santamaría, José Luis Simá, Fernando Arellano-Martín, José Luis Andrade

All Faculty Scholarship for the College of the Sciences

Premise of research. Epiphytic bromeliads endure intense seasonal environmental changes in the canopy of dry tropical deciduous forests. The analysis of the physiological responses of these epiphytes to environmental changes can be useful in assessing their plasticity, vulnerability, and adaptations to such extreme habitats.

Methodology. We measured microenvironmental variables and water relations for plants of the epiphytic bromeliad Tillandsia brachycaulos in three microhabitats within the canopy of a dry tropical forest. We measured individual plants for seasonal and spatial differences in light, leaf temperature, osmotic potential, cell wall elasticity, and relative capacitance as indications of their physiological responses …

Environmental Soft Law As A Governance Strategy, Cary Coglianese

All Faculty Scholarship

Soft law governance relies on nongovernmental institutions that establish and implement voluntary standards. Compared with traditional hard law solutions to societal and economic problems, soft law alternatives promise to be more politically feasible to establish and then easier to adapt in the face of changing circumstances. They may also seem more likely to be flexible in what they demand of targeted businesses and other entities. But can soft law actually work to solve major problems? This Article considers the value of soft law governance through the lens of three major voluntary, nongovernmental initiatives that address environmental concerns: (1) ISO 14001 …

Impacts Of Forest Management And Timber Harvest Practices On Karst Critical Zone Processes In Tongass National Forest, Alaska, Anna Gwendolyn Harris

Masters Theses & Specialist Projects

This study characterizes the throughfall, hydrogeochemistry, dissolution rates, and carbon sources of two proximate temperate rainforest cave systems within the Tongass National Forest in Southeast Alaska (Tongass). Study sites include: an old-growth forest, characterized by having never been logged (containing Walkabout Cave system); and a previously logged – within thirty years, second-growth forest (containing Zina Cave system). Precipitation data were recorded over a five-month period at 10-minute intervals, to understand the effects of throughfall between the altering old and second-growth canopies. At each major spring for the two cave systems, high-resolution data were collected from June 29 through November 21, …

Insights On Dissolved Organic Matter Production Revealed By Removal Of Charge-Transfer Interactions In Senescent Leaf Leachates, Karl M. Meingast, Brice K. Grunert, Sarah A. Green, Evan S. Kane, Nastaran Khademimoshgenani

Michigan Tech Publications

Dissolved organic matter (DOM) is a critical part of the global carbon cycle. Currently, it is understood that at least a portion of the chromophoric DOM (CDOM) character can be described through an electronic interaction of charge transfer (CT) complexes. While much work has been done to understand the influence of CT on soil and aquatic reference standard DOM, little is known about the influence of CT in fresh terrestrially derived DOM. In this study, leaf litter leachates from three tree species were treated (reduced) with sodium borohydride to determine the contribution of CT on a source of fresh terrestrial …

Airborne Hyperspectral Data Application In Stress Detection Of Blueberry Fields And Ash Trees, Catherine Chan

Electronic Theses and Dissertations

Water management and irrigation practices are persistent challenges for many agricultural systems. Changing seasonal and weather patterns impose a greater need for understanding crop deficiencies and excesses (e.g. water, sunlight, nutrients) for optimal growth while allocating proper resources for prompt response. The wild blueberry industry is at heightened susceptibility due to its unique growing conditions and uncultivated nature. Early detection of stress in agricultural fields can prompt management responses to mitigate detrimental conditions including drought and disease. Remote sensing has provided timely and reliable information covering large spatial extents, while novel applications in hyperspectral data and imaging spectroscopy have shown …

Fostering Climate Change Resilience: A Socio-Ecological Forest Systems Approach, Alyssa R. Soucy

Electronic Theses and Dissertations

As climate change continues to impact socio-ecological systems, those that rely on natural resources are highly sensitive to climatic changes. Maine’s forest industry provides for the economic and social well-being of many residents and is especially vulnerable to climate change impacts. Changes in growing season length and timing, forest health threats imposed by insects and pathogens, extreme weather events, shifting forest composition, and changes in natural disturbance severity and frequency have already begun, and are projected to continue, to impact forest systems in the Northeastern U.S. While climate change presents a threat to forest systems, opportunities also arise due to …

The Influence Of Environmental Variables On The Height Growth Of Loblolly Pine (Pinus Taeda) In The Western Gulf, Osakpamwan Edo-Iyasere

Electronic Theses and Dissertations

Understanding the effects of environmental factors on stand growth is important in optimizing forest management plans. This study investigated the effects of soil and climate factors on the height growth (site index) of loblolly pine (Pinus Taeda L.) using data collected from permanent plots established in intensively-managed plantations across East Texas and Western Louisiana. The Chapman-Richards model was selected as the base model to describe the height-age relationships and important soil and climate variables were incorporated into the models as model parameter coefficient adjustors. Our results showed that the most important factors for predicting site index were nitrogen …

A Preliminary Investigation Of The Impact Of Forest Management Practices On Microhabitat Abiotic Variables In The Southern Appalachian Mountains, Jasmine Williamson, Allison Bailey, Jacob Lougee, David Patterson, Jessica Patterson

Georgia Journal of Science

Existing research has demonstrated that forest management practices (e.g., clear-cutting, planting) can dramatically impact animal communities. This is particularly the case with amphibian populations due to their sensitivity to microhabitat alterations. However, few studies have investigated the manner by which forest management practices impact the abiotic variables most relevant to healthy amphibian populations. In this study we investigated how spatially localized forest management practices (i.e., at the scale of hundreds of meters) alter the microhabitat variables that have been shown important to amphibian population distributions. We assessed the relationship between forest composition and microhabitat abiotic variables across three localities with …

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 …

Influence Of Timber Harvesting Operations And Streamside Management Zone Effectiveness On Sediment Delivery To Headwater Streams In Appalachia, Daniel Bowker, Jeffrey W. Stringer, Christopher D. Barton

Forestry and Natural Resources Faculty Publications

Disturbances created by timber harvesting equipment and associated haul roads and skid trails can create overland sediment flows (sediment paths), especially in steeply sloping terrain, leading to stream sedimentation. This study investigated the effect of variables associated with GPS tracked harvest equipment movement, skid trail development and retirement, topography, and streamside management zone (SMZ) width and tree retention on sediment delivery to streams. While the intensity of harvest equipment traffic was not correlated with sediment path development, the presence and location of skid trails were. All of the sediment paths were found to originate at water control structures, influenced by …

Quantitative And Qualitative Approaches To Assess Tree Vigor And Stand Health In Dry Pine Forests, Nancy Grulke, Craig Bienz, Kate Hrinkevich, Jason Maxfield, Kellie Uyeda

Biology Faculty Publications and Presentations

Despite a critical need to evaluate effectiveness of forest treatments in improving stand health, practitioners lack quantitative, repeatable metrics to assess tree vigor and stand health. We evaluated canopy and whole tree attributes of ponderosa pine (Pinus ponderosa Dougl. Ex Laws) related to carbon balance, water balance, and susceptibility to insects and pathogens in dry, pine-dominated forest stands during a multi-year drought, an environmental challenge to stand resilience. Metrics of trees in two unmanaged, and seven treated forested stands, in both uplands and lowlands to develop the quantitative approach. Whole tree and crown attributes including needle length and color, branchlet …

Simulated Mine Land Reclamation Impact On Biomass Partitioning And Nutrient Contents In Loblolly Pine, Osarumen Egharevba

Electronic Theses and Dissertations

Forest productivity on reclaimed mine land is hindered by soil compaction. Different techniques have been used to alleviate the effect of compaction to various degrees of success. The Forestry Reclamation Approach (FRA) was developed in the Appalachians and has been used to improve forest productivity on reclaimed mines in this region. The FRA provides a step by step method designed to reduce compaction, control erosion, provide land stabilization and accelerate forest succession. This method had not been evaluated in the Gulf Coastal Plain, where the pan scraper reclamation method is commonly used. However, using pan scrapers increases mine soil compaction …

Tapping The Sweet Spot: Predicting The Suitability Of A Woodlot’S Potential To Transition Into A Productive Sugarbush In Maine, Deven M. Teisl

Non-Thesis Student Work

Through conversations with Dr. Sara Velardi, a postdoctoral research associate who has been doing research on maple producers’ scale management decisions in Maine, most current owners and operators in the maple syrup industry have the common interest of expanding their current operations, but they are unsure of how to approach that problem. Due to these current issues, my research focused on creating a sugarbush assessment tool. This assessment tool consists of a set of guidelines which can be utilized by current or future producers and can be used to easily assess woodlots without having to hire a consulting forester to …

Post-Fire Changes In Interior Alaska's Vegetation Composition, Jannike E. Allen

University Honors Theses

Global warming is altering the fire regime of interior Alaska, which may have cascading effects on the prevalence of forest types and species dominance across this region. Our objective was to investigate the relationship between vegetation composition and fire in the boreal forest of interior Alaska. We utilized data from over 700 plots sampled across the landscape designated as the Tanana region by the US Forest Service for Forest Inventory Analysis (FIA), as well as fire history records. We compared biomass and stem density of conifer and hardwood forest types, as well as individual tree species, across a gradient of …

A Comparison Of Fuel Reduction Methods For Wildfire Risk Management And Climate Change Resiliency In Mixed Conifer Forests In The Sierra Nevada, Heather Navle

Master's Projects and Capstones

Wildfires in the mixed conifer forests of California’s Sierra Nevada have been a common and natural disturbance for thousands of years, historically occurring every 3 to 30 years. The flora and fauna of the mixed conifer forest have evolved to depend on low to moderate severity wildfires for reproduction, foraging, and habitat. However, the Sierra Nevada has experienced dramatic environmental changes over the past ~150 years as a result of three main factors: wildfire suppression, climate change, and habitat loss. Because of the threat wildfires pose to human lives, property and timber harvest, they have been suppressed to an extent …

Reviewing Fire, Climate, Deer, And Foundation Species As Drivers Of Historically Open Oak And Pine Forests And Transition To Closed Forests, Brice B. Hanberry, Marc D. Abrams, Mary A. Arthur, J. Morgan Varner

Forestry and Natural Resources Faculty Publications

Historically open oak and pine savannas and woodlands have transitioned to closed forests comprised of increased numbers of tree species throughout the eastern United States. We reviewed evidence for and against a suite of previously postulated drivers of forest transition focused on (1) change in fire regimes, (2) increased precipitation, (3) increased white-tailed deer densities, and (4) loss of American chestnut. We found that fire and fire exclusion provide a parsimonious mechanism for historical dominance by open forests of fire-tolerant oak and/or pine species and subsequent transition to closed forests with fire-sensitive tree species that fill the vertical profile. Based …

Modeling Species Distribution And Habitat Suitability Of American Ginseng (Panax Quinquefolius) In Virginia, Jacob D. J. Peters

Masters Theses, 2020-current

American ginseng (Panax quinquefolius) is a well-known and sought-after medicinal plant native to North America that is facing increased threat of extinction due to overharvesting, herbivory, and habitat loss. Species distribution and habitat suitability models may be valuable to landowners interested in sustainable harvest or to institutions interested in the conservation and restoration of the species. With unequal sampling efforts across a region of interest, it is likely that some locations with appropriate habitat may be misrepresented in model predictions. This study refined a state-derived species distribution model for ginseng through increased sampling effort across the Cumberland Plateau …

Shifting Public Perception: Climate Change Means Living With Fire And Smoke, Robert Froembling

Seattle Journal of Technology, Environmental, & Innovation Law

The urgency to prepare for the climate crisis has never been greater. We are currently living in the sixth mass extinction and the effects are only going to accelerate. We will inherit more wildfires, larger wildfires, and more frequent wildfires.

This piece is not meant to stoke fear in its readers or be depressing, but to shift public perception on what our future holds by evaluating the laws and science presented to us. This piece will look at regional and federal regulations and assess the increased rate of forest fires and the grave public health concerns from stagnant smoke specifically …

A Floristic Survey Of Andalusia: A Historic Preservation Site In Baldwin County, Georgia, William Pharr

Biology Theses

A survey of the vascular plants of Andalusia, a historic preservation site located along Highway 441 north of Milledgeville in Baldwin County, Georgia, was conducted between August 2018 and February 2020. The site was the late home of esteemed author, Flannery O’Connor, and resides along the Georgia fall line, making it a historically significant area that could yield a unique plant community convergence, as well as rare endemic species. This floristic inventory provides baseline data on the species and plant communities of Andalusia for use in future studies regarding the flora of this area. A total of 191 vascular species …

Extreme Fire As A Management Tool To Combat Regime Shifts In The Range Of The Endangered American Burying Beetle, Alison K. Ludwig, Daniel R. Uden, Dirac Twidwell

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

This study is focused on the population of federally-endangered American burying beetles in south-central Nebraska. It is focused on changes in land cover over time and at several levels of spatial scale, and how management efforts are impacting both the beetle and a changing landscape. Our findings are applicable to a large portion of the Great Plains, which is undergoing the same shift from grassland to woodland, and to areas where the beetle is still found.

Correcting Tree-Ring Δ13c Time Series For Tree-Size Effects In Eight Temperate Tree Species, Matthew A. Vadeboncoeur, Katie A. Jennings, Andrew P. Ouimette, Heidi Asbjornsen

Earth Systems Research Center

Stable carbon isotope ratios (δ¹³C) in tree rings have been widely used to study changes in intrinsic water-use efficiency (iWUE), sometimes with limited consideration of how C-isotope discrimination is affected by tree height and canopy position. Our goals were to quantify the relationships between tree size or tree microenvironment and wood δ¹³C for eight functionally diverse temperate tree species in northern New England, and to better understand the physical and physiological mechanisms underlying these differences. We collected short increment cores in closed-canopy stands and analyzed δ¹³C in the most recent 5 years of growth. …

Spruce Budworm In Maine 2020 Annual Report, Michael Parisio, University Of Maine Cooperative Forestry Research Unit, Maine Forest Service

General University of Maine Publications

As growing spruce budworm populations continue to fluctuate in Maine, the Maine Forest Service, University of Maine Cooperative Forestry Research Unit (CFRU), and our cooperator network are tracking populations carefully in anticipation of an approaching outbreak.

A comprehensive spruce budworm (SBW) monitoring program requires a multi-pronged approach. It relies on using methods such as pheromone trapping, light trapping, overwintering L2 larval sampling, and both ground and aerial survey. At the core of the Maine Forest Service (MFS) monitoring program lies the extensive pheromone trap network throughout western and northern Maine's spruce-fir forests. A permanent pheromone trap network was first established …

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 …

Influence Of Forest-To-Silvopasture Conversion And Drought On Components Of Evapotranspiration, Adam P. Coble, Alexandra R. Contosta, Richard G. Smith, Nathan W. Siegert, Matthew A. Vadeboncoeur, Katie A. Jennings, Anthony J. Stewart, Heidi Asbjornsen

Natural Resources & the Environment

The northeastern U.S. is projected to experience more frequent short-term (1-2 month) droughts interspersed among larger precipitation events. Agroforestry practices such as silvopasture may mitigate these impacts of climate change while maintaining economic benefits of both agricultural and forestry practices. This study evaluated the effects of forest-to-silvopasture (i.e., 50% thinning) conversion on the components of evapotranspiration (transpiration, rainfall interception, and soil evaporation) during the growing season of 2016. The study coincided with a late-summer drought throughout the northeastern U.S., which allowed us to also evaluate the effects of forest-to-silvopasture conversion on drought responses of multiple tree species, including Pinus strobus, …

Modeling Post-Fire Successional Trajectories Under Climate Change In Interior Alaska Using Landis Ii, Shelby A. Weiss

Systems Science Friday Noon Seminar Series

Alaska boreal forest ecosystems are experiencing a greater frequency of wildfire relative to the region’s historic fire regime. These increases in fire frequency, as well as annual burned area, increase the probability of forests re-burning within shorter intervals than were experienced historically. Such changes to the fire regime have the potential to shift successional trajectories in this ecosystem. To better understand potential changes in vegetation composition following short-interval, repeat fires, we are using LANDIS-II, a forest landscape model, to simulate changes in forest composition in response to climate change and increasing fire frequency. This seminar will include a description of …