Physical Sciences and Mathematics Commons^™

Developing An Enhanced Forest Inventory In Maine Using Airborne Laser Scanning: The Role Of Calibration Plot Design And Data Quality, Stephanie Willsey

Electronic Theses and Dissertations

Forests provide essential ecosystem services such as carbon sequestration, clean water, lumber, and more. It is important that foresters be able to collect accurate forest inventories, especially in a changing climate. Foresters need to know what is in the forest not only to manage for the economic benefits, but also to manage for social acceptability and ecological soundness to prevent further degradation of these ecosystem services. One way to collect accurate and precise forest inventories is through the utilization of remote sensing products. These enhanced forest inventories (EFIs) can be done at varying resolutions that are contingent on the plot …

Carbon Dioxide Emissions From Deadwood In Forests Of The Northeastern United States, Zoe Read

Electronic Theses and Dissertations

As the climate changes, understanding the sources and sinks of greenhouse gases such as carbon dioxide (CO₂) is increasingly important. However, several components of the carbon cycle within forests remain poorly understood. For example, knowledge gaps exist in our understanding of CO₂ emissions from coarse woody material (CWM; logs and stumps), including how emissions change over time, how they are influenced by environmental variables, and how they compare to soil and ecosystem-level CO₂ emissions.

To fill these knowledge gaps, we examined CO₂ emissions from CWM at three sites. We sampled 18 red spruce (Picea …

Quantifying Spatial Heterogeneity Of Wild Blueberries And Crop Water Stress Monitoring Using Remote Sensing Technologies, Kallol Barai

Electronic Theses and Dissertations

The wild blueberry is one of the major crops of Maine, with significant economic value and potential health benefits. Due to global climate change, drought impacts have been increasing significantly in recent years in the northeast region of the USA, causing significant economic losses in the agricultural sectors. It has been predicted to increase further in the future. Changing patterns of the elevated atmospheric temperatures, increased rainfall variabilities, and more frequent drought events have made the wild blueberry industry of Maine vulnerable, suggesting the adoption of novel approaches to mitigate the negative impacts of global climate changes. Also, wild blueberry …

Assessing The Long-Term Effects Of Natural Disturbance-Based Silvicultural On The Avian Assemblage At The Acadian Forest Ecosystem Research Program, Carl Pohlman

Electronic Theses and Dissertations

Active forest management alters the resources available to forest-obligate species. Large-scale intensive management practices where timber production is the primary objective can lead to notable ecological changes in forest ecosystems. A key concept of ecological forestry is to design forest management activities to emulate natural disturbance regimes as a way to maintain the ecological integrity of forests. The Acadian Forest Ecosystem Research Program (AFERP) was undertaken as an experimental demonstration of management reflective of the region’s disturbance regime, which typically produces small canopy gaps. AFERP includes nine research areas assigned to three silvicultural treatments: unharvested control, small gap (expanding-group selection …

Forest Disturbance And Occupancy Patterns Of Carnivores: Results Of A Large-Scale Field Study In Maine, Usa, Bryn E. Evans

Electronic Theses and Dissertations

Understanding trends in the abundance and distribution of carnivores is important at global, regional and local scales due to their ecological role, their aesthetic and economic value, and the numerous threats to their populations. Carnivores in Maine range from the American black bear (Ursus americanus), to numerous native mesocarnivore species, such as American marten (Martes americana), fisher (Pekania pennanti), coyote (Canis latrans), red fox (Vulpes vulpes), bobcat (Lynx rufus), Canada lynx (Lynx canadensis) and to two small weasel species (Mustela erminea and Neogale frenata). …

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 …

Mountain Livelihoods In A Time Of Change: A Case Study Of Upper Mustang In Nepal, Sandesh Shrestha

Electronic Theses and Dissertations

A case study was conducted in a remote Himalayan village—Yara—in the Upper Mustang region of Nepal. The goal of this study was to understand and assess the livelihood strategies of local people in the village. The study focused on understanding the socio-economic and environmental driving factors of livelihood vulnerability, prevalent livelihood activities, emergent livelihood strategies, and resulting livelihood outcomes in the village. We used multiple data generation methods, which included both qualitative social science and quantitative biophysical components. For the qualitative component, we utilized multiple data generation methods including key informant interviews, semi-structured household interviews, group discussions, and field observations. …

Paper Structure Formation Simulation, Tyler R. Seekins

Electronic Theses and Dissertations

On the surface, paper appears simple, but closer inspection yields a rich collection of chaotic dynamics and random variables. Predictive simulation of paper product properties is desirable for screening candidate experiments and optimizing recipes but existing models are inadequate for practical use. We present a novel structure simulation and generation system designed to narrow the gap between mathematical model and practical prediction. Realistic inputs to the system are preserved as randomly distributed variables. Rapid fiber placement (~1 second/fiber) is achieved with probabilistic approximation of chaotic fluid dynamics and minimization of potential energy to determine flexible fiber conformations. Resulting digital packed …

Improving Conservation Of Declining Young Forest Birds Through Adaptive Management, Anna Buckardt Thomas

Electronic Theses and Dissertations

Early successional forest and shrubland habitats are collectively called young forest. Changes in disturbance regimes and land use conversion resulted in declines of young forest and associated wildlife across eastern North America. Conservation of declining young forest birds relies on the maintenance and creation of young forest habitats used for breeding. American Woodcock (AMWO; Scolopax minor) and Golden-winged Warbler (GWWA; Vermivora chrysoptera) are two declining young forest species. Conservation plans for both species use an adaptive management framework, which is an iterative process of planning, management actions, and monitoring and evaluation, in the context of species conservation goals. Adaptive management …

Climatic Range Filling Of North American Trees, Benjamin Seliger

Electronic Theses and Dissertations

Understanding the degree to which species distributions are controlled by climate is crucial for forecasting biodiversity responses to climate change. Climatic equilibrium, when species are found in all places which are climatically suitable, is a fundamental assumption of species distribution models, but there is evidence in support of climate disequilibria in species ranges. Long-lived, sessile organisms such as trees may be especially vulnerable to being outpaced by climate change, and thus prone to disequilibrium. In this dissertation, I tested the degree to which North American trees are in equilibrium with their potential climatic ranges using the ‘range filling’ metric, which …

Nitrogen Cycling During A Period Of Environmental Change, Kaizad Patel

Electronic Theses and Dissertations

Natural and anthropogenic disturbances have altered the N cycle on the regional to global scale. Although numerous studies have examined the effects of chronic atmospheric N deposition on ecosystem processes, less is known about intra-annual variability of these processes, or how these responses might be altered under conditions of changing climate. The work described in this dissertation focuses on the effects of a changing chemical and physical climate, particularly terrestrial N processes (a) during Maine’s changing winters, and (b) in response to chronic elevated N additions.

Subnivean winter soil processes were examined at the Dwight B. DeMerritt Forest (DBDF) and …

New Approaches To Mapping Forest Conditions And Landscape Change From Moderate Resolution Remote Sensing Data Across The Species-Rich And Structurally Diverse Atlantic Northern Forest Of Northeastern North America, Kasey R. Legaard

Electronic Theses and Dissertations

The sustainable management of forest landscapes requires an understanding of the functional relationships between management practices, changes in landscape conditions, and ecological response. This presents a substantial need of spatial information in support of both applied research and adaptive management. Satellite remote sensing has the potential to address much of this need, but forest conditions and patterns of change remain difficult to synthesize over large areas and long time periods. Compounding this problem is error in forest attribute maps and consequent uncertainty in subsequent analyses. The research described in this document is directed at these long-standing problems.

Chapter 1 demonstrates …

Immersed In Fire: The Use Of Virtual Reality As An Attitude Assessor And Boundary Object In Wildland Fire Management, Casey Olechnowicz

Electronic Theses and Dissertations

Interest in using prescribed burning as a forest management tool to promote forest health and regeneration is growing in Maine. The goal for this research was to better understand the way that the public perceives prescribed burning practices in wildland-urban interfaces, with an emphasis placed on how immersive imagery, closely related to virtual reality (VR), compares to traditional communication methods. We specifically focus on the social acceptability of prescribed burning and analyze how the level of immersive imagery is related to that acceptability (Ahn, 2015; Bricken, 1990; Fogg, Cuellar, and Danielson, 2009; Smith 2015; Wiederhold, Davis, and Wiederhold, 1998). The …

Individual Tree Measurements From Three-Dimensional Point Clouds, Elias Ayrey

Electronic Theses and Dissertations

This study develops and tests novel methodologies for measuring the attributes of individual trees from three-dimensional point clouds generated from an aerial platform. Recently, advancements in technology have allowed for the acquisition of very high resolution three-dimensional point clouds that can be used to map the forest in a virtual environment. These point clouds can be interpreted to produce valuable forest attributes across entire landscapes with minimal field labor, which can then aid forest managers in their planning and decision making.

Biometrics derived from point clouds are often generated on a plot level, with estimates spanning many meters (rather than …

Early Life Stage Characteristics Of Six Acadian Conifer Species: Germination And Seedling Development In A Changing Climate, Jason D. Schatz

Electronic Theses and Dissertations

Global climate change will drastically alter regional climates. The influence of these changes on the distribution and relative abundance of forest trees is both critically important and subject to substantial uncertainty. It will be particularly important to understand the effects of different climate scenarios on the early life stages of major tree species, because: 1) Early life stage performance and survival strongly influence the abundance of mature trees of a given species, 2) Trees are most sensitive to environmental variation during their early life stages, and 3) Our knowledge of the response of Acadian Forest tree species to environmental variation …

Digital Vertical Aerial Camera System For High-Resolution Site Inspections In Conservation Easment Monitoring, Kenton Williams

Electronic Theses and Dissertations

A three-level satellite to ground monitoring scheme for conservation easement monitoring has been implemented in which high-resolution imagery serves as an intermediate step for inspecting high priority sites. A digital vertical aerial camera system was developed to fulfill the need for an economical source of imagery for this intermediate step. A method for attaching the camera system to small aircraft was designed, and the camera system was calibrated and tested. To ensure that the images obtained were of suitable quality for use in Level 2 inspections, rectified imagery was required to provide positional accuracy of 5 meters or less to …

Aesthetic Values Of Five Primary Wood Transporting Methods Common To Northern New England, Michael C. Eckley

Electronic Theses and Dissertations

Throughout northern New England and across the country, increasing populations and the exurbanization of rural forested landscapes have had a tremendous impact on forest management. As forested areas become more populated, society has become more exposed to the sights and sounds associated with different forest operations. As a result, aesthetics are increasingly driving public reaction to and concern about forestry practices, especially timber harvesting. How people perceive forestry harvesting can be significant in defining the future of forest management, particularly in more populated woodlands. The objective of this study was to better understanding public values as they relate to timber …

A Comparison Of The Ecological Integrity Of Headwater Streams Draining Harvested And Un-Harvested Watersheds In The Western Mountains Of Maine, U.S.A., Darlene Siegel

Electronic Theses and Dissertations

Physical, chemical, and biological characteristics of four headwater streams draining forested watersheds were compared to determine the effectiveness of Riparian Management Zones (RMZs) in protecting aquatic ecological integrity from the effects of forest harvesting. Two of the watersheds were harvested with a 30% sheltenvood cut and a 75 foot buffer was left adjacent to the streams. The other two watersheds were un-harvested and were used as reference conditions for comparison with the harvested watersheds. General environmental conditions in these four headwater streams during the study period were characterized as follows. Each stream was located within a mixed- wood forest dominated …

Effects Of Fiberimatiux Interactions On The Interfacial Deformation Micromechanics Of Cellulose-Fiberipolymer Composites, William Tai-Yin Tze

Electronic Theses and Dissertations

The overall objective of this dissertation was to gain an understanding of the relationship between interfacial chemistry and the micromechanics of the cellulose-fiber/polymer composites. Regenerated cellulose (lyocell) fibers were treated with amine-, phenylamine-, phenyl-, and octadecyl-silanes, and also styrene-maleic anhydride copolymer. Inverse gas chromatography was conducted to evaluate the modified surfaces and to examine the adsorption behavior of ethylbenzene, a model compound for polystyrene, onto the fibers. Micro-composites were formed by depositing micro-droplets of polystyrene onto single fibers. The fiber was subjected to a tensile strain, and Raman spectroscopy was employed to determine the point-to-point variation of the strain- and …

The Short And Long-Term Effects Of Herbicide Application In Maine Clearcuts On Ant Communities (Hymenoptera: Formicidae), Kerry Frances Lough

Electronic Theses and Dissertations

The short and long-term effects of glyphosate application on the diversity and abundance of ants in Maine clearcuts was assessed in a two-year study. Glyphosate is applied to release coniferous trees from suppression by competition with deciduous vegetation after a forest is clearcut. Previous research indicates glyphosate has limited immediate and long-term effects on non-target fauna, though specific species can be affected. Limited research on the effects of herbicides on insects indicates some initial decrease in insect populations. Beneficial insects, such as pollinators and predators, positively influence the forest ecosystem, but little research has examined the effects of herbicide application …

Representational Analyses Of Conservation Lands In Maine, Stephanie Orndorff

Electronic Theses and Dissertations

The three studies reported here (i.e., statewide, southern Maine, and state and federal wildlife areas) identify what areas should be conserved to represent the natural diversity of Maine. Geographic Information System (GIs) technology was used to conduct the analyses comparing the distribution of abiotic and biotic variables representing natural diversity on and off conservation lands. In the statewide analysis, 10 environmental variables were compared on and off conservation lands using ArcGrid with a cell resolution of 1.86 x 1.86 km. The areas found to contain variables that were underrepresented were. combined to identify and map regions with under-represented characteristics. The …

Impact Of Preservative Treatments And Fungal Exposure On Phenolic Fiber Reinforced Polymer (Frp) Composite Material Utilized In Wood Reinforcement, Cihat Tascioglu

Electronic Theses and Dissertations

When wood products are exposed to environmental conditions conducive to biodeterioration, wood preservation becomes a necessity, especially when long-term utilization is desired. Although considerable literature exists on the treatment of laminated timbers and wood composites with wood preservatives, almost no information is available on the exposure of Fiber Reinforced Polymer (FRP) composites to wood preservative chemicals. In this work, FRP material was treated with common preservative chemicals and the effect of wood preservative treatments on mechanical properties of FRP material were investigated. Although the longitudinal elastic modulus was unaffected, some longitudinal strength losses were recorded for CCA and CDDC (water …

Determining Atmospheric Deposition Inputs To Two Small Watersheds At Acadia National Park, Sarah J. Nelson

Electronic Theses and Dissertations

Two small upland watersheds have been gauged and monitored at Acadia National Park since 1998. Cadillac Brook watershed burned in a wildfire in 1947. Hadlock Brook watershed has been undisturbed for several centuries, and serves as the reference site. Precipitation and throughfall volume and chemistry data have been collected using wetonly and continuously open collectors. Hydrologic and chemical inputs to the sites have been determined for each site. Differences in watershed and vegetation characteristics control the input of water and major ions to these watersheds. Vegetation type was the dominant control on enhancement of precipitation across the heterogeneous watersheds. Relative …

The Role Of Forest Soils In A Northern New England Effluent Management System, Leslie B. Nelson

Electronic Theses and Dissertations

The Carrabassett Valley Sanitary District in Carrabassett Valley, Maine has utilized both a forest spray irrigation system and a Snowfluent™ system for the treatment of their wastewater effluent. This study was designed to evaluate potential changes in soil properties after approximately 20 years of treatment in the forested spray irrigation site and three years of treatment in the field Snowfluent™ site. In addition, grass yield and composition were evaluated on the field study sites. After treatment with effluent or Snowfluent™, soils showed an increase in soil exchangeable Ca, Mg, Na, and K, base saturation, and pH. While most constituents were …

Fire And Its Effects On Mercury And Methylmercury Dynamics For Two Watersheds In Acadia National Park, Maine, Kenneth B. Johnson

Electronic Theses and Dissertations

Cross-continental movement of contaminated air masses and prevailing wind direction. Sites covered with softwood vegetation also received higher Hg deposition than other vegetation types because of the higher scavenging efficiency of the canopy structure. MeHg deposition was not affected by these factors. Hg deposition was lower in Cadillac Brook watershed (burned) than in Hadlock Brook watershed (unburned) because regeneration after the fire was dominated by mixed hardwood, whereas softwoods dominate the landscape in Hadlock Brook watershed. The lower deposition could also be a result of the watershed aspect; Cadillac Brook watershed faces southeast to east and Hadlock Brook watershed faces …

Monitoring Dioxin Levels In Maine Rivers With Semipermeable Membrane Devices, Heather A. Shoven

Electronic Theses and Dissertations

The Maine Department of Environmental Protection (DEP) currently monitors river dioxin levels through the sampling and destructive analysis of fish. Recent state law mandates that by December 31, 2002, the dioxin concentrations in fish downstream of a bleached Kraft pulp and paper mill are not to exceed the concentrations in fish upstream of the mill (38 M.R.S.A. §420-A). The objective of this thesis project was to develop an alternate method for determining Kraft mill compliance to this Dioxin law. This new method that uses semipermeable membrane devices (SPMDs) circumvents many of the concerns generated by the upstream-downstream fish test. An …

The Chemical Mechanism Of A Brown-Rot Decay Mimtic System And Its Application In Paper Recycling Processes, Yuhui Qian

Electronic Theses and Dissertations

This work is aimed at improving our current knowledge of the non-enzymatic inecl~anisins involved in brown-rot decay, as well as the exploration of potential applications of a brown-rot mimetic model system in paper recycling processes. The study was divided into two parts. The first part focussed on the chemical mechanisms involved in chelation and reduction of iron by a low molecular weight chelator (isolated from the brown-rot fungus Gloeophyllz~m tmbeum) and its model compound 2,3- dihydroxybenzoic acid (2,3-DHBA). Chelation as well as free radical generation mediated by this system were studied by ESR measurement. The results indicate that the effects …