Natural Resources and Conservation Commons^™

Environmental And Silvicultural Factors Associated With Northern White-Cedar (Thuja Occidentalis) Seedling Regeneration In Harvested Lowlands, Victoria J. Hunter

Dissertations, Master's Theses and Master's Reports

Northern white-cedar (Thuja occidentalis) plays a vital ecological and cultural role in North America's eastern hemi-boreal forests, yet its regeneration is often sparse and difficult to manage, especially in lowland conditions. To assess factors influencing cedar seedling densities, we surveyed 430 plots across 135 harvested cedar-dominated lowland stands (1–72 years post-harvest) over a broad geographic region. Most plots (73%) harvested in the last century and 90% of those harvested in the last decade had absent or understocked cedar seedling densities (0–5000/ha). Seedling density increased with time-since-harvesting, density of retained overstory cedar trees, denser canopy closure, and decreased with …

Survival And Spatial Ecology Of North American River Otters (Lontra Canadensis) In West Virginia, Laurel Marie Glover

Graduate Theses, Dissertations, and Problem Reports (ETD)

Wildlife reintroductions function to regain wildlife populations in areas where they have been extirpated or greatly diminished. One such species that has been reintroduced to several states is the North American river otter (Lontra canadensis). The West Virginia Division of Natural Resources (WVDNR) conducted a river otter reintroduction effort between 1984-1997, releasing 245 individuals into the state. The reintroduction was deemed a success with the WVDNR opening a regulated trapping season for river otters in 2011, allowing trappers to take one river otter per season. As the population has reestablished in West Virginia, several management challenges have arisen …

Integrating Sustainable Practices Into Lean Engineering: Applying The Engineering For One Planet Framework In Manufacturing Engineering Technology Education, Dalya Ismael, Vukica M. Jovanovic, Murat Kuzlu, Charles Lowe, Lisa Bosman

Engineering Technology Faculty Publications

A growing number of manufacturers are recognizing significant financial and environmental benefits from adopting sustainable business practices. Sustainable manufacturing refers to the production of goods through processes that are economically sound, minimize environmental impact, and conserve energy and natural resources. Lean engineering, a comprehensive approach to decision-making and leadership within manufacturing organizations, has proven effective in driving sustainable practices. Key strategies include waste elimination, value identification, value stream mapping, flow creation, pull system establishment, and continuous improvement. Both lean manufacturing and sustainability share a common focus on minimizing waste. Lean principles address seven types of waste: transport, inventory, motion, waiting, …

Advancing Sustainability In Civil Engineering Technology Through The Engineering For One Planet Framework, Dalya Ismael, Vukica M. Jovanovic, Murat Kuzlu, Charles Lowe, Lisa Bosman

Engineering Technology Faculty Publications

As global environmental challenges intensify, integrating sustainability into engineering technology education is increasingly critical. Yet, many programs lack comprehensive methods to embed sustainability principles, leaving graduates underprepared to address real-world environmental issues. Courses on sustainability often approach it in isolated or superficial contexts, unable to capture its complexity. The purpose of this study is to showcase one approach for embedding the Engineering for One Planet (EOP) framework into the Sustainable Building Practices course within the Civil Engineering Technology Department. The newly developed curriculum integrated learning outcomes from three EOP topics: Environmental Impact Assessment, Materials Selection, and Systems Thinking. Students were …

Assessment Of The Genetic Population Structure And Extent Of Clonality In A Rare Serpentine Endemic, Lathyrus Biflorus T.W. Nelson & J.P. Nelson (Fabaceae), Using Ddrad Sequencing, Ashley Dickinson

Cal Poly Humboldt theses and projects

Lathyrus biflorus, or the two-flowered pea, is a rare herbaceous perennial restricted to a single population in Northern California. The species is considered critically imperiled but remains unprotected under state or federal endangered species acts. Despite its rarity, little is known about its life history, reproductive biology, or genetic diversity. Using genome-wide reduced representation sequencing, this study aimed to address these gaps by investigating the molecular evidence of clonality, the number and diversity of genets (unique genetic individuals which can be made up of one or many clonal units or ramets), and overall genetic health of the population. My …

Snag Failure And Fuel Recovery Following Stand-Replacing Fire In The Klamath Mountains, Joseph R. Nicholas

Cal Poly Humboldt theses and projects

High-severity wildfires can produce extensive patches of standing dead trees (snags), which later contribute to surface fuel loading and present a hazard as they decay and fall. In the Klamath Mountains of northwestern California and southwestern Oregon, recent increases in the occurrence of large stand-replacing wildfires have raised concerns about fuel and vegetation recovery trajectories, the likelihood of future fires, and resulting impacts to local communities. Nevertheless, the post-fire environment may offer opportunities to enhance ecological and community resilience. Estimates of snag failure and fuel loading can support land management planning and risk assessment following wildfire, though such work is …

North American River Otter (Lontra Canadensis) Prey Selection Of Wintering Waterbirds In A Wetland Complex, Gina Yael Culver

Cal Poly Humboldt theses and projects

Generalist predators are assumed to take a wide variety of prey throughout an annual cycle, often switching between food sources depending on availability. Prey selection is often studied by way of variables such as prey age class, body size, and various topics related to anti-predator behaviors, all variables used to measure how predators target prey. Following prior studies in coastal Northern California documenting that river otters (Lontra canadensis) had selected waterbirds as prey, we identified undigested prey items in scat to evaluate prey selection of waterbirds at the Arcata Marsh and Wildlife Sanctuary (AMWS). We compared feathers found …

Home Range, Habitat Use, And Fall Migration Of Lewis’S Woodpeckers In The Eastern Cascade Range, Oregon, Cameron Piper

Cal Poly Humboldt theses and projects

Lewis’s woodpecker (Melanerpes lewis), a burn specialist, is experiencing range-wide population declines despite increasing fire activity in the western U.S. The White River Wildlife Area in Oregon hosts the state's only year-round population, raising questions about their breeding, habitat use, and migration. In summer 2024, we tracked nine woodpeckers using telemetry to estimate home range size and overlap. Full home ranges averaged 428 ha, with 66 ha core areas, and showed evidence of growing after nesting. Home ranges overlapped extensively (Full: 91 ± 13%; Core: 63 ± 29%), though individuals had distinct areas of intense use. Males had …

An Economic And Production Analysis Of Seaweed Farms In California And The Pacific Northwest, Brian Donovan

Cal Poly Humboldt theses and projects

Since the early 2010s, the seaweed aquaculture industry has steadily expanded in the United States, with states like Alaska, Maine, Hawaii, and Connecticut leading the way in the development of this emerging sector. However, information gaps remain concerning certain aspects of the domestic seaweed aquaculture industry. The purpose of this study was to examine the status of the seaweed aquaculture industry along the West Coast of the United States; specifically in the states of California, Oregon, and Washington. Seaweed farmers in these states were invited to voluntarily complete surveys asking important production, economic, and commercial questions regarding their operations. Data …

Common Raven Habitat Selection Along The Northern California Coast, Alon Averbuj

Cal Poly Humboldt theses and projects

Nest predation by common ravens (Corvus corax) is considered one of the most significant barriers to the recovery of the population of the federally threatened western snowy plovers (Anarhyncus nivosus nivosus) in Northern California. To increase productivity of snowy plovers, conservation managers in Northern California employ three main techniques; placing symbolic fencing to deter pedestrian entrance to snowy plover nesting areas, invasive vegetation cutback, and deposition of oyster shells to increase snowy plover nest crypsis. However, little is known on how these techniques affect habitat selection of ravens in the area. I modeled habitat selection of …

Experimental Investigation On Hydrogen-Rich Syngas Production Via Gasification Of Common Wood Pellet In Bangladesh: Optimization, Mathematical Modeling, And Techno-Econo-Environmental Feasibility Studies, Md Sanowar Hossain, Mujahidul Islam Riad, Showmitro Bhowmik, Barun K. Das

Research outputs 2022 to 2026

Since hydrogen produces no emissions, there is increasing interest in its production throughout the world as the need for clean and sustainable energy grows. Bangladesh has an abundance of biomass, particularly wood pellets, which presents a huge opportunity for gasification to produce hydrogen. Gasification of mahogany (Swietenia mahagoni-SM) and mango (Mangifera indica-MI) wood is performed in a downdraft gasifier to evaluate the impact of particle size, equivalence ratio, and temperature on hydrogen gas composition and gasifier performance. Under the optimal conditions determined by central composite design-response surface methodology (CCD-RSM) optimization, gasification of SM and MI wood can greatly increase hydrogen …

A Swirling Offering: Climate Change Impacts On Incense And Other Useful Alpine Plants Of Bhutan, Nidup Gyeltshen, Choki Gyeltshen, Sangay Dema, Suresh K. Ghimire, Natalie Konig, Robbie Hart

Research outputs 2022 to 2026

Climate change impacts on social-ecological systems —such as useful plant harvest— can be elucidated through local perceptions and ecological monitoring. To better understand how these two approaches may show convergent or divergent perspectives on a shared system, we conducted semi-structured interviews on climate change impacts on useful plants in the alpine region of Central Bhutan, contextualized with results from ecological monitoring at the same site. Participants reported 42 useful alpine plant species. Incense plants were the most frequently cited and prioritized in free-lists (three times more likely to be mentioned first), ahead of other common uses (food, medicine). Most participants …

Ecological Resources Of A Heavily Modified And Utilised Temperate Coastal Embayment: Cockburn Sound, Peter J. Mitchell, Daniel E. Yeoh, Kurt N. Krispyn, Claire N. Greenwell, Sorcha Cronin-O’Reilly, Delphine B.H. Chabanne, Glenn A. Hyndes, Danielle Johnston, David V. Fairclough, Claire Wellington, Alan Cottingham, Gary Jackson, Jeffrey V. Norriss, Matias Braccini, Hector Lozano-Montes, Chandra P. Salgado Kent, Erin Clitheroe, Alissa Tate, James W. Penn, Marion Massam, Neil R. Loneragan, James R. Tweedley

Research outputs 2022 to 2026

Coastal environments and their associated biota provide numerous environmental, economic and societal services. Cockburn Sound, a temperate embayment on the lower west coast of Western Australia, is immensely important for the State and adjacent capital city of Perth. However, urbanisation and associated terrestrial and marine development has the potential to threaten this important ecosystem. This study collated published and unpublished data to review the current state of the ecological resources of Cockburn Sound and describe how they have changed over the past century. Post-WWII, the embayment began undergoing pronounced anthropogenic changes that limited oceanic water exchange, increased nutrient load, modified …

Natural Hydrogen Soil Gas Emissions Near Harvey, Perth Basin: A Comparative Study Of Survey Methods, Krista Davies, Peter W. Haines, Charmaine Thomas, Leon Normore

Research outputs 2022 to 2026

Quantifying natural hydrogen soil gas emissions and their controlling factors is critical for assessing hydrogen storage viability and improving exploration strategies. This study provides the first detailed comparison of hydrogen emissions near the DMP Harvey-2 well in the Perth Basin and compares the effectiveness of repeated point surveys and autonomous monitoring in capturing emission variability. Hydrogen concentrations ranged from 0 to >1000 ppm in point surveys, with transient pulses up to 598 ppm detected through continuous monitoring, indicating episodic release. Repeated point surveys successfully captured the overall range of emissions but failed to resolve dynamic processes, such as abrupt flux …

Linking Empirical Data And Numerical Simulation To Characterize Dynamic Fire Behavior Associated With Interacting Firelines, Marta Sergeevna Jerebets

Graduate Student Theses, Dissertations, & Professional Papers

Understanding fuel pattern-fire process relationships is key for predicting fire behavior and effects with follow-on benefits to proactive fire management and model validation. To characterize dynamic fire behavior, this thesis leverages empirical data and numerical simulation through two complementary studies.

In the first study, longwave thermal sensors aboard unmanned aerial systems (UAS) were used to capture fine-scale fire behavior in two experimental grass burns. A novel paired design was used to quantify the effects of fuel arrangement on fire behavior with 3.66 m diameter treatments cut to a height of 0.15 m. The treatments ephemerally reduced fire rate of spread …

In The Footsteps Of Moose: Using Non-Invasive Techniques To Identify Cause-Specific Calf Mortalities And Evaluate Moose (Alces Alces) Movements Pertaining To Mineral Lick Locations On Ancestral Lands Of The Grand Portage Ojibwe, Anna B. Weesies

Electronic Theses and Dissertations

Following a sharp moose (Alces alces; mooz, Anishinaabemowin, Ojibwe language) population decline in northeastern Minnesota during the early 2000s, the Grand Portage Band of Lake Superior Chippewa initiated a long-term moose collaring effort to assess survival and mortality causes. Moose are a culturally important species to the Band, with annual subsistence hunts held on the Reservation and adjacent 1854 Ceded Territory. Continued research guides culturally appropriate management decisions aimed at bolstering calf and adult survival, helping to preserve this moose in Minnesota today and for subsequent generations. Chapter 1 identifies cause-specific calf mortality rates in this multi-predator system using minimally …

Huchum: The Legacy Of Fire Suppression, Indigenous Land Management, And Media Representation, Carolyn Coyne

Pomona Senior Theses

In my thesis, I examine how various forms of news media from the 1900s to present day in Ohlone territory have framed a particular hegemonic ideology around fire that matches early colonial journal entries – an ideology that is fueled by fear, sensationalism, and exclusion and directly commits violence against the Ohlone people. I investigate this time period because this is when modern news corporations, like The New York Times, rose into prominence. Specifically, I question how media representations of fire inform regulations over controlled burns; what are the similarities in discourse between media framing and policy? What tactics are …

A Critical Juncture: The Convergence Of Natural Resource Management And Tribal Sovereignty, Anna Aleta Butterfield

Graduate Student Portfolios, Professional Papers, and Capstone Projects

This portfolio reflects the work I’ve done in my four years as a dual degree student, pursuing a Master of Science in Environmental Studies and a juris doctorate degree, and focuses on policies and laws surrounding natural resource management. It touches on how those policies relate to and expand or constrict the exercise of sovereignty by indigenous populations.

This piece first considers the effects of plastic on salmon populations and those indigenous groups that rely on salmon for subsistence and cultural purposes. The remaining three pieces focus on various aspects of the Confederated Salish and Kootenai Tribes - Montana Water …

Investigating Non-Invasive Survey Methods And Building A Predictive Occupancy Model For Harlequin Ducks (Histrionicus Histrionicus) In Western Montana And Northern Idaho, Holli Ann Holmes

Graduate Student Theses, Dissertations, & Professional Papers

Harlequin Ducks (Histrionicus histrionicus; HADU) are an imperiled sea duck that breeds along white-water mountain streams, but challenges in surveying them have made it difficult to understand population trends in their Northern Rocky Mountain breeding population. In this study we had two objectives: (1) evaluate non-invasive survey methods for detecting HADU on their breeding grounds in Western Montana and Northern Idaho, and (2) develop an occupancy model to predict potential breeding stream use for HADU across the region. First, we assessed the efficacy of ground-based foot surveys (GBS), environmental DNA (eDNA), and camera traps to detect breeding HADU during …

Ecology-Driven Machine Learning For Predicting Risk Of Spread For Aquatic Invasive Species., Leif Eric Howard

Graduate Student Theses, Dissertations, & Professional Papers

Effective management of aquatic invasive species (AIS) requires predictive tools that leverage environmental and ecological data to forecast spread into uninvaded areas. However, species distribution models (SDMs) often struggle to capture key invasion processes such as dispersal, propagule pressure, and biotic interactions. This thesis integrates ecological, dispersal, and environmental predictors within a machine learning framework to enhance AIS risk prediction and model transferability across space.

In Chapter 2, 61 novel predictors were developed for 2,203 Minnesota lakes to model zebra mussel (Dreissena polymorpha) occurrence, incorporating variables related to propagule pressure (e.g., boat visitation), community composition (e.g., fish species …

Microbial Community Stabilization By Restored Oyster Reefs: Implications For Blue Carbon Storage, Natalie Boydstun

College of Graduate Studies: Theses & Dissertations

Coastal ecosystems provide critical carbon sequestration services, yet the microbial mechanisms underlying carbon storage remain poorly understood, particularly in non-vegetated habitats. This study investigated whether restored oyster reefs (Crassostrea virginica) enhance sediment carbon storage potential by stabilizing microbial communities and promoting efficient organic matter processing. I hypothesized that reef-mediated sediment stabilization and organic deposition would create conditions favoring microbial degradation of complex carbon compounds into stable soil organic matter, ultimately supporting anaerobic carbon storage. To test this, I compared sediment biogeochemistry, enzyme activity, and microbial community structure between three restored oyster reef sites and two unstructured control sites …

Sandy Subterranean Estuaries Minimize Groundwater Nitrogen Pollution Impacts On Coastal Waters, Xiaogang Chen, Isaac R. Santos, Jinzhou Du, Bochao Xu, Joseph J. Tamborski, Ding He, Neven Cukrov, Christian J. Sanders, Jianan Liu, Peiyuan Zhu, Yan Zhang, Ling Li

OES Faculty Publications

Widespread anthropogenic activities pollute groundwater that eventually seeps out to the coastal ocean. Here, we resolve nutrient transformations and fluxes in 11 sandy subterranean estuaries (STEs) with contrasting nutrient sources and development trajectories. Coastal groundwater nitrogen pollution stems from sewage discharge and land use change. Anthropogenically derived groundwater nutrient fluxes with high N/P ratios (∼170) accounted for 22%–61% of riverine inputs into China's coastal waters, providing an additional source of nutrients that can fuel coastal eutrophication and algal blooms. Sandy STEs remarkably attenuated ∼84% of nitrogen pollution, minimizing the impact of submarine groundwater discharge (SGD) on coastal water quality. Hence, …

Characterization Of Microbial Biofilms On Marine Plastics: Community Development And Density Implications For Vertical Transport Dynamics, Gregory M. Joern, Rut Pedrosa-Pàmies, Xiangtao Jiang, Zhanfei Liu, Alexander B. Bochdansky

OES Faculty Publications

Marine plastic pollution poses a significant and escalating threat to ocean ecosystems, with microbial colonization on plastics playing a critical role in determining their environmental fate. Despite the recognized importance of microbial biofilms, their composition, dynamics, and functional contributions on buoyant plastics remain poorly understood. In this study, we leveraged a novel integrative approach by simultaneously employing 16S, 18S, and ITS sequencing alongside microscopy, lipidomics, pigment analysis, adenosine triphosphate and biogenic silica quantification. This comprehensive methodology allowed for a thorough characterization of microbial growth and community dynamics on plastic debris in a mid-latitude, tidal sub-estuary. Our analyses consistently identified diatoms, …

Bridging The Gap Between Plot-Level And Landscape-Scale Analysis For Wildfire Risk Assessment, Vanessa Leigh Niemczyk

Graduate Student Theses, Dissertations, & Professional Papers

Remote sensing technology has advanced greatly over the past couple of decades proving its ability to aid in wildfire risk assessment and improve our understanding of forest structure and fuel inventory across the landscape. While some aerial and satellite sensors perform better than others, they all have a common weakness, their reduced ability to capture understory fuels with high detail. Terrestrial laser scanning is an emerging solution due to its understory perspective. This research leverages the beneficial aspects of both terrestrial laser scanning and various aerial- or satellite-based remote sensing platforms (aerial laser scanning, digital aerial photogrammetry, and Sentinel-2) to …

Community-Wide Impacts Assessment Of Silver Carp (Hypophthalmichthys Molitrix) In The Ohio River, Luka Marques

Graduate Theses, Dissertations, and Problem Reports (ETD)

Invasive species can cause measurable impacts on the properties of recipient ecosystems, with effects that often vary spatially and temporally. One of the most complex and pressing invasion cases in the United States involves invasive carp. Invasive carp have quickly expanded throughout the Mississippi River Basin, with ecological impacts that may vary across space and time. Silver Carp has the potential to provoke community-wide impacts on native fish abundances and food webs of native fish communities. My study area ranged from the confluence of the Mississippi River and the Ohio River to R.C. Byrd Lock and Dam. The Ohio River …

Modelling The Impacts Of Recreational Catch-And-Release Variability On Fish Stock Dynamics, Brett Crisafulli

Theses: Doctorates and Masters

Recreational fisheries often lack sufficient data for robust stock assessments, and post-release mortality (PRM) of discarded fish, particularly demersal species, poses a significant threat to sustainability. Because demersal fish often experience higher PRM (often due to barotrauma and stress), the substantial global interest in their recreational fisheries (e.g., Australia, Gulf of Mexico, Western Baltic Sea) raises conservation concerns. This study employs three distinct modelling approaches, applied to four reef-dwelling demersal species, to support effective recreational fisheries management by addressing data uncertainty, unintended consequences of management changes, and PRM effects. Specifically, this thesis (1) evaluates variability in average weights of recreationally-caught …

Shrubsteppe Birds Under Fire: Guiding Post-Wildfire Habitat Restoration In The Whiskey Dick And Quilomene Units, Washington, Kevin Clements

All Master's Theses

Bird species, globally, are declining at an alarming rate. Birds of the shrubsteppe are particularly vulnerable to habitat loss caused by agricultural development, invasive vegetation, and heightened wildfire frequency and severity. Fire and invasive vegetation create a positive feedback cycle that threatens complete conversion of shrubsteppe to grasslands. Restoring habitat following wildfire is a top priority for land managers. As bioindicators of ecosystem health, bird populations reflect landscape changes and restoration efficacy. I analyzed bird populations in the Whiskey Dick and Quilomene units of the L.T. Murray Wildlife Area in Kittitas County, Washington following the 2022 Vantage Highway fire. Using …

Identifying The Impacts Of Land Use/Land Cover Changes On Ecosystem Services From A Geospatial Perspective In Albany County, Kyaw Khaung Thant Zin

Electronic Theses & Dissertations (2024 - present)

Ecosystem services encompass the broad array of direct and indirect advantages that people derive from nature and its ecosystems. Considering accelerating environmental change and degradation, recognizing the importance of these services is more crucial than ever, as they illustrate the many ways in which healthy ecosystems sustain human life. However, these services are diminishing at a rapid and unprecedented rate, raising global concern over both the transformations taking place and their root causes. Among the leading threats, land-use change stands out as a particularly significant one, influenced by a variety of driving factors. Albany County, New York, characterized by its …

Mxene-Based Materials For Enhanced Water Quality: Advances In Remediation Strategies, Ali Mohammad Amani, Milad Abbasi, Atena Najdian, Farzaneh Mohamadpour, Seyed Reza Kasaee, Hesam Kamyab, Shreeshivadasan Chelliapan, Mostafa Shafiee, Lobat Tayebi, Ahmad Vaez, Atefeh Najafian, Ehsan Vafa, Sareh Mosleh-Shirazi

Electrical & Computer Engineering Faculty Publications

Two-dimensional MXenes are promising candidates for water treatment because of their large surface area (e.g., exceeding 1000 m²/g for certain structures), high electrical conductivity (e.g., >1000 S/m), hydrophilicity, and chemical stability. Their strong sorption selectivity and effective reduction capacity, exemplified by heavy metal adsorption efficiencies exceeding 95 % in several studies, coupled with facile surface modification, make them suitable for removing diverse contaminants. Applications include the removal of heavy metals (e.g., achieving >90 % removal of Pb(II)), dye removal (e.g., demonstrating >80 % removal of methylene blue), and radioactive waste elimination. Furthermore, 3D MXene architecture exhibit enhanced performance in antibacterial …

Estimating Mariana Monitor (Varanus Tsukamotoi) Density With Multiple Methods On Islan Dåno’, Guam, And Its Relevance To Guam Rail (Hypotaenidia Owstoni) Conservation, Jack T. Christie

Cal Poly Humboldt theses and projects

The Mariana monitor (Varanus tsukamotoi), or hilitiai, is a medium-sized varanid lizard found throughout the Mariana islands. On Islan Dåno’, a small islet off the southwest coast of Guam, hilitai coexist with one of the rarest birds in the world, the Guam rail (Hypotaenidia oswtoni), or ko’ko’, which were introduced to the island in 2010. Since 2009, hilitai have been lethally removed from the island to reduce possible predation on ko’ko’. After 15 years of removal efforts, I sought to 1) estimate the abundance and density of hiltai, 2) assess the effect of removal effort and …