Forest Sciences Commons^™

Fertilization And Tree Species Influence On Stable Aggregates In Forest Soil, Jacob E. Kemner, Mary Beth Adams, Louis M. Mcdonald, William T. Peterjohn, Charlene N. Kelly

Faculty & Staff Scholarship

Abstract: Background and objectives: aggregation and structure play key roles in the water-holding capacity and stability of soils and are important for the physical protection and storage of soil carbon (C). Forest soils are an important sink of ecosystem C, though the capacity to store C may be disrupted by the elevated atmospheric deposition of nitrogen (N) and sulfur (S) compounds by dispersion of soil aggregates via acidification or altered microbial activity. Furthermore, dominant tree species and the lability of litter they produce can influence aggregation processes. Materials and methods: we measured water-stable aggregate size distribution and aggregate-associated organic matter …

Determining The Effects Of Imidacloprid On Non-Target Soil Organisms In Hemlock Stands, Braley Burke

Graduate Theses, Dissertations, and Problem Reports (ETD)

The hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae), is an invasive insect that is causing mortality of eastern hemlock trees, Tsuga canadensis, and Carolina hemlock trees, Tsuga caroliniana, across the eastern United States. To protect these ecologically important tree species, a neonicotinoid insecticide, imidacloprid, is commonly used. Imidacloprid is an effective treatment and can remain effective against HWA for four to six years but long-term (≥ one year after application) non-target effects of imidacloprid on forest ecosystems are not well-studied. This study examined terrestrial non-target effects of imidacloprid in hemlock stands with different treatment histories to …

Analyzing Safety Audits To Improve Logging Safety Performance, George Daniel Nolan Jr

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examines logging safety audits to determine how different variables, and differing amounts of time between audits, affect the outcome of safety score performance. To collect the data for this study a three-page paper audit was used that examined five areas of the logging site which include: Personal protective equipment (PPE), general, felling, mobile equipment and, landing and loading.

The study analyzed 3 aspects of the audit which were the total score and the sub-categories of PPE and felling since they were the two heaviest weighted sections. The analysis only included audits that had a 5 percent or greater …

Soil Microbial Nitrogen-Transforming Genes Influenced By Tree Species And Fertilization In An Appalachian Hardwood Forest, Emma G. Fox-Fogle

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many forest ecosystems have been receiving elevated nitrogen (N) deposition due to human activity. Increased ecosystem N threatens soil fertility, water and air quality, and modifies the soil microbially-mediated N cycle in complex ways. The current study investigates how the abundance of key functional N cycling genes within soil bacteria is altered by N deposition and further mediated by different dominant tree species at the Fernow Experimental Forest, WV. Soils were analyzed from two watersheds, where watershed 3 (WS 3) has been receiving experimental applications of N fertilizer that are 2x historic ambient N deposition and 5x the current ambient …

Three Essays On “Energy , Environment, And Developmental Economics”, Bolarinwa Ajanaku

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation examines topics related to renewable energy development and investment planning, energy markets, environment degradation and economic development. The substantial ecological costs of deforestation are well known and considered globally important due to biodiversity loss, land degradation, soil erosion, and contributions to climate change. The first essay focuses upon understanding the tradeoff between development and deforestation in Africa. In the second essay, spatial analysis and Geographic Information System (GIS) are applied to determine potential locations for wind farms development in the state of West Virginia. Lastly, the third essay examines the role of wind power penetration on wholesale electricity …

Climatic Drivers Of Growth In Mixed Conifer Forests Of The Sierra Nevada For Different Tree Sizes And Thinning Treatments, Andrew M. Hirsch

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Mediterranean region of northern California is projected to get increasingly warmer under all Intergovernmental Panel on Climate Change (IPCC) emission scenarios, with future precipitation projections not showing much of a trend. This poses a problem to the already dry summers that are experienced in the Mediterranean region of California. If precipitation does not increase alongside temperatures, the dry seasons will likely only get drier. The use of dendroclimatology to assess how mixed conifer species in the Sierra Nevada responded to past climate is a key resource that can be used to infer how trees may respond to a future …

Environmental Controls On The Terrestrial Water Cycle In Forested Mountain Ecosystems., Luis Andrés Guillén

Graduate Theses, Dissertations, and Problem Reports (ETD)

Water is a key resource to natural ecosystems and human societies alike, and the water cycle is fundamentally linked to the climate and the characteristics of catchments. However, the challenges posed by environmental change makes it imperative to understand how the water cycle is affected by biotic and abiotic factors, in particular, in areas that are crucial sources of water like forested headwater catchments. Therefore, this doctoral dissertation aims to advance the knowledge on the dynamics between climate, vegetation and landscape that determine the water balance of forested mountain ecosystems. This document presents five chapters, an introductory chapter, three standalone …

Soil Response Of Helicopter Liming In The Monongahela National Forest, Jarrett Douglas Fowler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Soils in the Monongahela National Forest (MNF) are acidic due to sandstone parent material, acid deposition, uptake of base cations by vegetation, and release of organic acids by organic matter (OM) decomposition. Increases in soil acidity have caused declines in forest health and changed species composition and nutrient status. Liming can neutralize soil acidity, but no large-scale liming projects have been done on acid forest soils in the USA. In anticipation of acquiring funding for a proposed liming project in the MNF, in 2007 and 2009 10 sites were selected to sample and analyze soils before lime was applied. In …

Dietary Protein Content And Digestibility Influences Discrimination Of Amino Acid Nitrogen Isotope Values In A Terrestrial Omnivorous Mammal, John P. Whiteman, Mauriel Rodriguez Curras, Kelli L. Feeser, Seth D. Newsome

Biological Sciences Faculty Publications

RATIONALE: Ecologists increasingly determine the δ¹⁵N values of amino acids (AA) in animal tissue; "source" AA typically exhibit minor variation between diet and consumer, while "trophic" AA have increased δ¹⁵N values in consumers. Thus, trophic-source δ¹⁵N offsets (i.e., Δ¹⁵N_T-S) reflect trophic position in a food web. However, even minor variation in δ¹⁵N_{source AA} values may influence the magnitude of offset that represents a trophic step, known as the trophic discrimination factor (i.e., TDF_T-S). Diet digestibility and protein content can influence the δ¹⁵N values …

Perceived Stressors Of Filipinos In South Korea And The Development Of An Appreciative Resilience-Focused Wellness Program, Monica H. Walet, Emely D. Dicolen, Joeffrey M. Calimag

Journal of Public Affairs and Development

People are faced with numerous challenges brought by the COVID-19 pandemic. It has affected all the areas of their well-being - physical, psycho-emotional, social, financial, and spiritual. Overseas Filipinos, specifically the Filipinos in South Korea, are not exempted from these. It is in this light that this research analyzed the factors that affect the well-being of Filipinos in South Korea and propose a sustainable program that would provide the needed support to navigate their unique challenges and perceived requirements for personal growth. A total of 353 Filipinos from various sojourns participated in the survey: Employment Permit System workers, marriage migrants, …

Conifer Encroachment And Removal In A Northern California Oak Woodland: Influences On Ecosystem Physiology And Biodiversity, Gabriel S. Goff

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana) woodlands across their range are becoming increasingly threatened by encroaching Douglas-fir encroachment (Pseudotsuga menziesii) as a result of fire exclusion. Using water potential (Ψ), stomatal conductance (g_s), xylem water stable isotopes (dD), and three metrics of biodiversity, this study investigates the effects of conifer encroachment and removal at the ecosystem-scale. The study was set in an Oregon white oak woodland in northern California and compared three levels of encroachment before and after conifer removal. Findings indicate that heavily encroached stands have the least amount of water stress and gas …

Comparison Of Low-Cost Commercial Unpiloted Digital Aerial Photogrammetry To Airborne Laser Scanning Across Multiple Forest Types In California, James Edward Lamping

Cal Poly Humboldt theses and projects

Science-based forest management requires quantitative information about forest attributes traditionally collected via sampled field plots in a forest inventory program. Remote sensing tools, such as active three-dimensional (3D) Light Detection and Ranging (lidar), are increasingly utilized to supplement and even replace field-based forest inventories. However, lidar remains cost prohibitive for smaller areas and repeat measurement, often limiting its use to single acquisitions of large contiguous areas. Recent advancements in unpiloted aerial systems (UAS), digital aerial photogrammetry (DAP) and high precision global positioning systems (HPGPS) have the potential to provide low-cost time and place flexible 3D data to support forest inventory …

In-Flux: Economic And Community Adaptations Of Former Timber Mill-Towns In The American West, Cherilyn P. Ashmead

Cal Poly Humboldt theses and projects

Once built around natural resource extractive industries, rural communities’ economies are changing as the United States is transitioning away from its industrial past. While much research has focused on rural economic shifts from natural resource production toward amenity-driven economies (Morzillo et al., 2015; Winkler et al, 2007), less research has explored the economic and demographic trends in areas pursuing new modes of production. This two-part study focuses on an understudied region with historic ties to timber in dry mixed-conifer forests, much of which are under federal land management. With few natural amenity draws, the region has largely maintained production-based sectors. …

Evaluating Immaturity Risk In Young Stands Of The Serotinous Knobcone Pine (Pinus Attenuata), Katherine Marlin

Cal Poly Humboldt theses and projects

As wildfire becomes increasingly frequent, many plant populations risk local extirpation if fire recurs too soon, a problem dubbed “immaturity risk”. We studied the regeneration of a serotinous conifer species, knobcone pine (Pinus attenuata), as a function of the time between high-severity fires (6-79 years). We evaluated age, cone production, and regeneration at two burned sites in northern California, the Ranch Fire (2018) in Mendocino National Forest, and the Carr Fire (2018) in Whiskeytown National Recreation Area. We found an average of 30.5 filled seeds in closed, brown cones (42% viability of filled seeds). The bulk of the …

Post-Fire Effects In Chaparral And Oak Ecosystems Of Northern California, Abigail M. Jones

Cal Poly Humboldt theses and projects

The issue of wildfires, hazard fuels management, and post-fire tree mortality has become an increasingly common topic in the western United States. This thesis is composed of two studies, with the first study, Chapter 1, examining fuel treatment effectiveness and the second study, Chapter 2, striving to characterize post-fire mortality in oaks.

Prior to wildfire, fuel reduction projects may take place to decrease the likelihood of high severity fire around human infrastructure and communities. Within California’s chaparral ecosystems, common treatment types include hand-thinning, prescribed burning, mechanical mastication, and mechanical mastication followed with prescribed burning. Because chaparral has a longer historical …

Effects Of Bark Beetle Outbreaks On Forest Landscape Pattern In The Southern Rocky Mountains, U.S.A., Kyle C. Rodman, Robert A. Andrus, Cori L. Butkiewicz, Teresa B. Chapman, Nathan S. Gill, Brian J. Harvey, Dominik Kulakowski, Niko J. Tutland, Thomas T. Veblen, Sarah J. Hart

Geography

Since the late 1990s, extensive outbreaks of native bark beetles (Curculionidae: Scolytinae) have affected coniferous forests throughout Europe and North America, driving changes in carbon storage, wildlife habitat, nutrient cycling, and water resource provisioning. Remote sensing is a cru-cial tool for quantifying the effects of these disturbances across broad landscapes. In particular, Landsat time series (LTS) are increasingly used to characterize outbreak dynamics, including the presence and severity of bark beetle-caused tree mortality, though broad-scale LTS-based maps are rarely informed by detailed field validation. Here we used spatial and temporal information from LTS products, in combination with extensive field data …

Use Of Redwood Basal Hollows By Bats: A Focus On The Townsend's Big-Eared Bat On The North Coast Of California, Amon Jotesh Armstrong

Cal Poly Humboldt theses and projects

Loss of roosting resources, either through disturbance or removal, negatively affects bats. For sensitive species, such as the Townsend’s big-eared bat (Corynorhinus townsendii), determining roost requirements is a critical component in conserving their habitat. Such cavity roosting bats on the North Coast of California may use hollows in large redwood trees. In this study, I examined the factors determining the use of basal tree hollows by different bat species at eight redwood forest sites in Del Norte, Humboldt, and Mendocino Counties, California. Bat guano was collected from 179 basal hollow roosts from 2017 to 2018, and guano mass …

White Pine Blister Rust Distribution In New Hampshire 1900-2018: Exploring The Impacts Of An Exotic Pathogen On Forest Composition And Succession, Janine Marr

Antioch University Dissertations & Theses

White pine blister rust (WPBR) has been affecting New Hampshire’s white pines for more than a century, yet no data exist on the long-term effects of the non-native disease on the state’s forests, particularly with respect to the regeneration and sustainability of white pine, and forest succession. This study aimed to address the gaps in the literature by exploring: 1) the current distribution, incidence, and severity of WPBR in New Hampshire; 2) the application of two historical hazard ratings models, one climatic, and one biotic; and 3) the long-term effects of the disease on forest composition, structure, and succession. Historical …

A Spatiotemporal Assessment Of Fish Assemblage Response To Land-Use Change And The Evaluation Of Edna Metabarcoding For Describing Diverse Fish Communities, Timothy M. Owen

Theses and Dissertations

Fish assemblages are often assessed as a biological proxy for environmental health. While humans value healthy environments for the ecosystem services and recreational opportunities they provide, it is increasingly evident that such resources can be paradoxically degraded by anthropogenic activities. In this investigation, we studied the relationship between different intensities of anthropogenic land-use change and habitat-driven fish assemblage response across multiple spatiotemporal scales. Secondarily, we explored the efficacy of eDNA metabarcoding against conventional electrofishing techniques for the purpose of describing complete fish communities. This study was conducted in the Tuckahoe Creek basin near Richmond, Virginia. This James River tributary serves …

Influences On Conifer Drought Responses In Northern California, Wallis L. Robinson

Cal Poly Humboldt theses and projects

California is experiencing increasingly severe and prolonged droughts, which are contributing to changes in tree stress and forest mortality. Many factors affect a tree’s drought response, including competition, climate, and site and tree characteristics. Northern California provides a suitable venue to explore the effects of these factors, as it spans a variety of site conditions and includes habitat for conifers with different adaptations and requirements. This study used annual ¹³C discrimination and growth metrics to assess differences in drought resistance and resilience in conifers adapted to coastal and montane ranges at both wet and dry sites, as well as …