Life Sciences Commons^™

Soil Organic Carbon In Maine, Its Responses To Biochar Addition, And Climate Change, Xue Bai

Electronic Theses and Dissertations

Soil organic carbon (SOC), as one of the largest C pools in terrestrial ecosystems, plays a key role in governing soil ecosystem processes and climate regulation. Climate change concerns have resulted in a rapidly growing interest in understanding the potential for natural climate solutions (NCS) that include enhancing SOC sequestration and reduce net atmospheric greenhouse gas (GHG) emissions. This research focused on addressing information needs about SOC in Maine, specifically in evaluating available soil databases to accurately quantify SOC density and concentration, and study the response of selected representative Maine soils to biochar amendments under a changing climate.

Maine SOC …

Economics And Operational Decision Constraints Of Small-Diameter Tree Harvesting, Libin Thaikkattil Louis

Electronic Theses and Dissertations

Sustainably managed forests are crucial in balancing trade-off between various ecosystem functions and optimum product utilization. Improving the utilization of these renewable resources through diversified forest wood products faces various socio-economic, ecological, and cultural challenges. A major challenge faced by forest managers in the Northeastern United States is overstocked stands dominated by small-diameter trees (SDT). Major woody portion of the harvested residues is constituted by SDT and are typically of low value. Data from the national inventory indicates a high number of SDT in Northeastern forests such that the average size of all trees in the region is less than …

Utilization Of Secondary Processing Mill Residues In Maine To Produce Raw Materials For Manufacturing Wood-Plastic Composites (Wpcs), Geeta Pokhrel

Electronic Theses and Dissertations

The overall objective of this study was to explore the potential of utilizing secondary processing mill residues generated in Maine (1.6 million tons annually) in Wood-Plastic Composites (WPCs). Attributable to the huge shipping costs for transporting wood flour over long distances, wood pellets are explored as alternative feedstock for WPCs manufacturing. The mill residues from four species based on their abundance and potential applicability for utilization in WPCs manufacturing were used to make the two different feedstocks. The properties of the wood flour and pellets were studied along with the comparison of the properties of polypropylene-based WPCs using both of …

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). …

Cellulose Nanofibril Coated Bio-Based Composites For Food Serving Applications, Rakibul Hossain

Electronic Theses and Dissertations

Cellulose nanofibrils (CNFs) and lignin-containing cellulose nanofibrils (LCNFs) have excellent binding properties with lignocellulosic materials such as wood particles, cellulose fibers, and other particles. They also have excellent oil and grease barrier properties. A novel application by utilizing the binder and barrier properties of CNF and LCNF has been proposed. In this study, multi-layer oil-resistant food serving containers were made using cellulose nanofibril coated wood flour composites. Composites were made with different formulations by using LCNF from old corrugated containers (OCC) at different fines content and CNF at 20, 30, and 40% binder content combined with wood particles. LCNF and …

Climate Change And Forest Management Impacts On Tree Growth And Physiology, Kelly French

Electronic Theses and Dissertations

Projected changes in temperature and precipitation are expected to lead to declines in many forest tree species across the Northeastern United States. Red spruce (Picea rubens) and balsam fir (Abies balsamea) are two of the most common tree species in Maine that make up about 5.5 million acres of the state’s forest land. As such, future climate conditions pose a major challenge for management of these species, and it is unclear how management may mitigate or exacerbate the negative effects of climate change. Therefore, in this study we investigated how thinning to release suppressed red spruce influences understory microclimate, and …

Remote Sensing Identification Of Black Ash (Fraxinus Nigra) In Maine Via Hyper- And Multi-Spectral Imagery, John W. Furniss

Electronic Theses and Dissertations

North American ash species (Fraxinus spp.) are under dire threat from the invasive pest, emerald ash borer (Agrilus planipennis, EAB). Black ash (F. nigra) has shown no resistance to EAB while its cultural and ecological importance render it irreplaceable. Traditional field forestry techniques are not suitable for the large-scale identification of individual black ash trees to facilitate conservation, thus necessitating the need for other identification and classification techniques. The objective of this research is to develop remote sensing techniques that can be used to identify ash trees, in particular black ash, at the individual tree level using both hyperspectral and …

Understanding The Adhesion Mechanism In Mycelium-Assisted Wood Bonding, Wenjing Sun

Electronic Theses and Dissertations

The increasing environmental awareness has led to an increased interest in developing more sustainable materials as alternatives to petroleum-derived products. Among different nature-based products, fungal-mycelium-based bio-composites have gained considerable attention in various applications. Multiple materials with different densities and structures and potential applications can be fabricated by inoculating filamentous white-rot fungi in lignocellulosic materials and other substrates. Different from lower-density as-grown foam-like mycelium composites, higher-density mycelium-lignocellulosic panels have the potential to replace commercial particleboard and fiberboard bonded by petroleum-based resins. This kind of composite can be produced by directly adding heat and pressure to the low-density foams or by assembling …

Tree Responses To Moderate And Extreme Drought In The Northeastern United States, Ruth A. Van Kampen

Electronic Theses and Dissertations

Climate change is expected to lead to novel drought conditions in the Northeastern United States. Therefore, experimental studies that mimic these conditions are crucial to understand the potential impact on forests. Further, recent large scale dendrochronological studies suggest that spring and summer droughts may immediately impact tree growth while fall droughts may cause delayed impacts on growth the following growing season. Therefore, in this study, we investigated the impacts of six-week-long spring, summer, and fall droughts on the physiology and intra-annual growth on 288 saplings of six tree species native to the Northeastern United States. These species (deciduous broadleaf angiosperms, …

Forest Phenology In Maine: Trends And Drivers Over The Past Two Decades And Implications For Resource Managers, Valeria Briones

Electronic Theses and Dissertations

Rapid climate change in recent decades has impacted forest, coastal, and social systems globally. In the northeastern U.S., alterations to the seasonal timing and duration of phenology cycles are a direct result of increasing temperatures, and monitoring these changes serves as a valuable indicator to analyze the impacts of climate change. Furthermore, increasing temperatures can influence when and how visitors recreate in natural landscapes. In the past decade, outdoor spaces have seen an increase in the number of visitors, partly as a result of climate change, that has influenced how resource managers and tourism suppliers plan for and respond to …