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Full-Text Articles in Physical Sciences and Mathematics

Evaluating Benthic Macroinvertebrate Populations In Response To Scouring Events In The Trinity River, Ca, Liam Hay, Michael W. O'Neil, Chloe Pieper-Wasem Jan 2023

Evaluating Benthic Macroinvertebrate Populations In Response To Scouring Events In The Trinity River, Ca, Liam Hay, Michael W. O'Neil, Chloe Pieper-Wasem

Environmental Science & Management Senior Capstones

River systems across California have been impacted by appurtenant structures such as dams and diversions. These structures have had an adverse impact on Benthic invertebrate (BMI) communities by regulating river systems and changing the natural hydraulic pulses that follow seasonal precipitation. Benthic invertebrates are a critical food resource for salmonids and serve as an indicator of ecosystem health. Our study was interested in seeing the effects of scouring events on BMI in the Trinity River of Trinity County, C.A. Following a large precipitation event that occurred in the region in December 2022, an influx of water entered the river through …


Perceptions Of Trail Safety In Humboldt County, California: An Analysis Of Safety Concerns, Factors That Impact Trail Use, And The Value People Place On Trails, Natalie C. Arroyo Jan 2023

Perceptions Of Trail Safety In Humboldt County, California: An Analysis Of Safety Concerns, Factors That Impact Trail Use, And The Value People Place On Trails, Natalie C. Arroyo

Cal Poly Humboldt theses and projects

Trails in Humboldt County, California that are used for both transportation and recreation have myriad community benefits. However, people’s concerns about feeling safe can affect trail use, design, and development, as well as how trails are valued and perceived by residents. There has been a lack of information in Humboldt County about trail safety perceptions despite it being a factor that repeatedly arises in infrastructure planning and funding conversations. My research was focused on answering the following questions: (1) How do Humboldt County trail users perceive their safety on and near trails? (2) What factors affect these perceptions about safety, …


Analysis Of Benthic Macroinvertebrate Response To Restoration Flows And Scour In The Trinity River, Northern California, Sarah Gutierrez, Julie Avina Jan 2023

Analysis Of Benthic Macroinvertebrate Response To Restoration Flows And Scour In The Trinity River, Northern California, Sarah Gutierrez, Julie Avina

Cal Poly Humboldt Capstone Honor Roll

This study investigates the ecological impact of restoration flows and scouring events on benthic macroinvertebrate (BMI) communities within the Trinity River, an ecosystem historically impacted by anthropogenic activities. Central to this study is the examination of how hydrologic alterations, especially the construction of the Lewiston Dam, have influenced these vital ecological indicators. Using data collected earlier in 2023 from a current study by Benjamin King, we analyzed BMI samples from three river sites (Junction City, Pear Tree, and Lorenz Gulch), both prior to and following a major scouring event in January 2023. This paper utilizes statistical analyses, including ANOVA and …


Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer Jan 2023

Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer

Cal Poly Humboldt theses and projects

A growing interest in sustainable waste management and the implementation of new policies have prompted a shift towards alternative resource recovery methods for organic waste, including food waste. To effectively assess alternative food waste treatment scenarios, it is important to evaluate the life cycle impacts associated with each scenario. The storage phase of food waste, encompassing its accumulation in kitchens, and storage in bins for collection and transportation, has been overlooked as a source of greenhouse gases in previous studies. This investigation aimed to identify the greenhouse gases emitted during the initial five-day period of low-oxygen storage. An open dynamic …


Estimating Black Bear Population Parameters With Spatial Capture Recapture In A High Desert Mountain Ecosystem, Steffen D. Peterson Jan 2023

Estimating Black Bear Population Parameters With Spatial Capture Recapture In A High Desert Mountain Ecosystem, Steffen D. Peterson

Cal Poly Humboldt theses and projects

Black bear (Ursus americanus) populations have grown and recolonized historic range in California, and unharvested populations are currently poorly monitored by existing programs. In the Warner Mountains of northeast California, increasing issuance of bear depredation permits has underscored the importance of black bear population monitoring. To study population density, space-use, and demographics of this unharvested population, I established 10 non-invasive sampling clusters, comprising a 3 x 3 arrangement of 4-km2 grid-cells, across a 1,464 km2 study area and monitored hair snares over five 10-day sampling occasions in summer 2018. Fourteen microsatellite and two sex-specific genetic markers …


Changes And Relationships Of Soil Aluminum, Organic Matter, And Hydrogen Ion Concentration With Rye Cover Crop, Arron Wilder Jan 2023

Changes And Relationships Of Soil Aluminum, Organic Matter, And Hydrogen Ion Concentration With Rye Cover Crop, Arron Wilder

Cal Poly Humboldt theses and projects

Soil acidity is a common agricultural problem worldwide, as approximately 50% of all potentially arable soils are affected by pH limitations. At soil pH 3+) is considered to be the chemical form of aluminum in acid soil that hinders plant growth the most. Potentially, soil organic matter (SOM) can ameliorate the toxic effects of Al3+ on plants and microbes by binding with Al3+, thus preventing Al3+ (and other species of aluminum) from interacting in the rhizosphere. Increasing SOM also increases soil health indicators (i.e., microbial activity, soil water holding capacity, aggregate stability, porosity, etc.) while the …


Protecting Public Trust Resources In America's Private Forests: Case Studies In The Diversity Of U.S. State-Level Forestry Policies, Brita Ann Goldstein Jan 2022

Protecting Public Trust Resources In America's Private Forests: Case Studies In The Diversity Of U.S. State-Level Forestry Policies, Brita Ann Goldstein

Cal Poly Humboldt theses and projects

Privately-owned forests in the U.S. provide ecological and socioeconomic benefits to Americans. At the same time, they challenge common law principles that govern the administration of public goods. There is long-standing tension between private property rights, which entitles forest landowners to make land management decisions about their properties, and the role of state governments in protecting public trust resources on behalf of the general public. Each state chooses to protect public trust resources on private lands in a different way, meaning the U.S. is a patchwork of diverse private forest policy approaches. Describing this range of approaches can help inform …


On The Acceptance Of Urban Beavers In Martinez, California, Zane A. Eddy Jan 2021

On The Acceptance Of Urban Beavers In Martinez, California, Zane A. Eddy

Cal Poly Humboldt theses and projects

As ecosystem engineers, beavers construct complex riparian and wetland habitats that benefit many other species, including endangered salmonids. Through their landscape alterations, beavers also promote increased groundwater recharge and provide refugia during wildfires and high flow events by impounding water and allowing it to spread across the landscape. Prior to the North American colonial fur trapping campaigns, there were between 60 and 400 million beavers in North America. By the beginning of the 20th century, beavers were extirpated from many parts of the continent, however through human efforts, their population has since rebounded to between 10 and 15 million. The …


Assessing California Commercial Fishing Community Well-Being In The Context Of Marine Protected Area (Mpa) Formation, Samantha Cook Jan 2021

Assessing California Commercial Fishing Community Well-Being In The Context Of Marine Protected Area (Mpa) Formation, Samantha Cook

Cal Poly Humboldt theses and projects

Marine protected areas (MPAs)—defined geographic areas where fishing and harvesting activity is limited or restricted—have emerged as a popular marine biodiversity and climate resilience strategy worldwide. MPA monitoring efforts often follow MPA designation to help inform the adaptive management of MPAs and MPA networks. In 2012, California completed the largest statewide system of MPAs to date, consisting of 124 MPAs covering 16% of state waters. Following MPA implementation, the state initiated a long-term monitoring program (2019-2022) to help inform the 10-year MPA management review. This two-chapter thesis presents findings from a state-funded project to conduct long-term socioeconomic monitoring for human …


Response Of Invertebrate Drift To Dam-Release Restoration Pulse Flows From Lewiston Dam On The Trinity River, Ca, Jasmine S. Williamshen Jan 2021

Response Of Invertebrate Drift To Dam-Release Restoration Pulse Flows From Lewiston Dam On The Trinity River, Ca, Jasmine S. Williamshen

Cal Poly Humboldt theses and projects

The widespread construction of dams to regulate rivers has dramatically altered aquatic ecosystems, but these impoundments also provide a unique opportunity to support freshwater conservation goals by implementing functional flow regimes designed to mitigate dam-related impacts on fisheries. Drifting invertebrates are an important food source for stream-dwelling juvenile salmonids such that drift feeding can be an energetically profitable foraging strategy, yet the effect of streamflow alterations on invertebrate drift dynamics is largely undetermined. Drift net samples were collected on four days before and four days during the ascending limb (14-42 m3/s) of restoration pulse flows in April 2020 …


Can A Remote Sensing Approach With Hyperspectral Data Provide Early Detection And Mapping Of Spatial Patterns Of Black Bear Bark Stripping In Coast Redwoods?, Shayne R. Magstadt Jan 2021

Can A Remote Sensing Approach With Hyperspectral Data Provide Early Detection And Mapping Of Spatial Patterns Of Black Bear Bark Stripping In Coast Redwoods?, Shayne R. Magstadt

Cal Poly Humboldt theses and projects

The prevalence of black bear (Ursus americanus) bark stripping in commercial redwood (Sequoia sempervirens) timer stands has been increasing in recent years. This stripping is a threat to commercial timber production because of the deleterious effects on redwood tree fitness. This study sought to unveil a remote sensing method to detect these damaged trees early and map their spatial patterns. By developing a timely monitoring method, forest timber companies can manipulate their timber harvesting routines to adapt to the consequences of the problem. We explored the utility of high spatial resolution UAV-collected hyperspectral imagery as a …


Habitat Use And Prey Selection By Mountain Lions In An Altered Sagebrush Steppe Environment, Jonathan Ewanyk Jan 2020

Habitat Use And Prey Selection By Mountain Lions In An Altered Sagebrush Steppe Environment, Jonathan Ewanyk

Cal Poly Humboldt theses and projects

Throughout the American West there is an increasing trend of encroachment of woody vegetation on previously open sagebrush steppe habitat. The Modoc Plateau in northeastern California has not been excluded from this encroachment trend and has seen an increase in western juniper (Juniperus occidentalis) densities, likely as a result of long-term fire suppression. Mountain lions (Puma concolor) have not previously been studied on the Modoc Plateau, and there is potential for an increase in cover due to juniper encroachment to benefit the hunting behavior of lions. To better understand if the presence of cover is being …


Decay Of Woody Residues As The Counterfactual Treatment To Mobilization For Bioelectricity Generation, Max A. Blasdel Jan 2020

Decay Of Woody Residues As The Counterfactual Treatment To Mobilization For Bioelectricity Generation, Max A. Blasdel

Cal Poly Humboldt theses and projects

Decay of woody debris is a major carbon flux for forests. Decay processes are not well documented in forest modeling frameworks but play an important role in forest carbon cycling and life cycle assessments of forest-derived products. The main drivers of decay are species, vertical location, and climate. A database of literature values for decay by tree species was created to parameterize a larger model of California forestland carbon cycling. A novel methodology was applied to vary these decay values for each species spatially based on climatic drivers of decay. This resulted in decay values for each species and size …


Living Rivers, Cosmopolitan Activism, And Environmental Justice In The Bengal Delta, Daniel Adel Jan 2020

Living Rivers, Cosmopolitan Activism, And Environmental Justice In The Bengal Delta, Daniel Adel

Cal Poly Humboldt theses and projects

This thesis explores the social movements and civil society activism to protect the rivers that flow through Bangladesh—the cradle and terminal delta floodplain of the transboundary Ganges, Brahmaputra, and Meghna river systems—, as well as ways to build regional cooperation and watershed democracy in South Asia. The research drew on four overarching fields of study: environmental justice, southern environmentalism, ecological nationalism, and environmental governance. These four bodies of scholarship helped address the overarching question: how are civil society organizations analyzing and responding to the water diversions and degradation of Bangladesh’s transboundary rivers? Semi-structured interviews were conducted with civil society organizations …


Species Distribution Models For Three Deep-Sea Coral And Sponge Taxa In The Southern California Bight, Nissa Kreidler Jan 2020

Species Distribution Models For Three Deep-Sea Coral And Sponge Taxa In The Southern California Bight, Nissa Kreidler

Cal Poly Humboldt theses and projects

Deep-Sea Coral and Sponge (DSCS) species are signature taxa of deep-water habitats, however understanding the ecological mechanisms that drive their geographic distributions can be difficult to uncover due to the challenges of surveying deep-water ecosystems. A recent study on benthic assemblages in Southern California revealed statistical associations between several DSCS and demersal fishes, many of which are important to management agencies due to commercial or conservation concerns. Maps that predict where these DSCS may occur are needed for the management and protection of these DSCS taxa and the fauna that rely on them for habitat. In this thesis, I develop …


Sediment Production And Delivery From Timber Harvest Roads In Humboldt County, California, Chris P. Faubion Jan 2020

Sediment Production And Delivery From Timber Harvest Roads In Humboldt County, California, Chris P. Faubion

Cal Poly Humboldt theses and projects

Sediment delivery from unpaved actively-used and relatively un-trafficked forest roads are one of the most common sources of impairment to aquatic ecosystems. Hence the objectives of this study were to: 1) compare the variability in erosion rates from actively used and relatively un-trafficked timber harvest roads across multiple water years in Railroad Gulch; 2) identify segment scale controls on road surface erosion and road-to-stream connectivity; 3) develop storm-based and annual segment scale models to predict road sediment production and compare the accuracy of these models to WEPP: Road; and 4) estimate road-related sediment loads to streams.

Between 2014 and 2019 …


Exploring Community Knowledge And Perceptions Of Flooding And Sea-Level Rise In King Salmon, California, Kristina Kunkel Jan 2019

Exploring Community Knowledge And Perceptions Of Flooding And Sea-Level Rise In King Salmon, California, Kristina Kunkel

Cal Poly Humboldt theses and projects

The coastal community of King Salmon, California could be at the highest risk of relative sea-level rise on the entire U.S. West Coast. In 2019, the community already experiences severe flooding at least annually and may be regularly inundated as early as 2050. Until this study, there had been no documented effort to reach out to the community to show them future sea-level rise projections, understand the context of life in King Salmon, and listen to their reactions and perceptions. This research utilized a mixed methods grounded theory approach integrating semi-structured interviews with King Salmon stakeholders, qualitative data analysis, public …


Mechanisms And Spatial Patterns Of Bark Beetle-Associated Mortality Following Variable Density Thinning Treatments In A Sierra Mixed-Conifer Forest, Alexis Bernal Jan 2019

Mechanisms And Spatial Patterns Of Bark Beetle-Associated Mortality Following Variable Density Thinning Treatments In A Sierra Mixed-Conifer Forest, Alexis Bernal

Cal Poly Humboldt theses and projects

Long-term trends of tree mortality have increased over the last several decades, coinciding with above-average temperatures, high climatic water deficits, and bark beetle outbreaks. With the anticipation that drought and bark beetles may increase with climate change, uncertainty exists over the appropriate treatments that could ensure the future sustainability of forest resources and the ecosystem services that forests provide. Conventional thinning treatments are used to reduce stand density, with the assumption that reductions in competition can alleviate drought stress and enable trees to resist bark beetle attack. Alternative thinning treatments may also reduce stand density, but have a greater focus …


Making And Breaking Trust In Forest Collaborative Groups, Emily Jane Davis, Lee K. Cerveny, Donald R. Ulrich, Meagan L. Nuss May 2018

Making And Breaking Trust In Forest Collaborative Groups, Emily Jane Davis, Lee K. Cerveny, Donald R. Ulrich, Meagan L. Nuss

Humboldt Journal of Social Relations

There has been a recent increase in use of an organized, forest ‘collaborative’ group approach for multi-stakeholder input on federal forestlands in the U.S. West. This approach relies on the creation of shared trust to achieve social agreement. Yet growing critiques suggest a lack of trust in the U.S. Forest Service [Forest Service], between stakeholders, and the collaborative process itself. We conducted three comparative case studies of established forest collaborative groups in Oregon, Washington, and Idaho to ask how trust is created and damaged or broken in this context. We found multiple, interlinked dimensions to trust, including significant reliance on …


Who’S In Charge? The Role Of Power In Collaborative Governance And Forest Management., Patricia B. Orth, Antony S. Cheng May 2018

Who’S In Charge? The Role Of Power In Collaborative Governance And Forest Management., Patricia B. Orth, Antony S. Cheng

Humboldt Journal of Social Relations

Collaborative processes for working toward common management goals between individuals and organizations, despite their differences, emerged as one enduring legacy resulting from the Timber Wars in the American West during the late-1980s and the early 1990s. Power imbalances are often cited as a common problem in collaborative processes and can have a lasting, deleterious impact on the collaborative process and its outcomes. For all its importance, however, there is a yet unfulfilled need to understand the extent to which power and power imbalances affect collaborative relationships. Our research uses a case study approach to qualitatively analyze power dynamics within three …


The Role Of The Local Community On Federal Lands: The Weaverville Community Forest, Erin C. Kelly May 2018

The Role Of The Local Community On Federal Lands: The Weaverville Community Forest, Erin C. Kelly

Humboldt Journal of Social Relations

In the wake of the timber wars, communities across the American West have struggled to redefine their relationships to nearby federal forests. The timber-dependent model of the pre-Timber War era, with clear timber targets and economic outputs, has been replaced by more nuanced and less clearly-defined model: ecosystem management. This case study research uses interviews with participants in the Weaverville Community Forest (WCF) to explore the role of a community in managing its nearby federal lands. Momentum for the WCF flowed from a small group of citizens who were invested in the forest despite their cultural and ideological differences regarding …


An Opportunity To End The Timber Wars: How Collaboration In Southeast Alaska Has Helped To Dissipate Conflict, Diana K. Portner May 2018

An Opportunity To End The Timber Wars: How Collaboration In Southeast Alaska Has Helped To Dissipate Conflict, Diana K. Portner

Humboldt Journal of Social Relations

Forest management in the Tongass National Forest has been a topic of controversy for decades, due to the result of intense timber extraction in the mid-twentieth century. In recent years, collaborative approaches to management, beginning with a federally chartered advisory committee, have offered opportunities to overcome the seemingly intractable conflict. While a new culture of collaboration is emerging in Southeast Alaska, the region still faces challenges associated with the implementation of these approaches. This commentary explores the history of the conflict, factors that contributed to the success of collaborative approaches to land management in the region, and continued challenges that …


There Is A Fish In My Forest And Other Post-Timber War Musings, Mike Miles May 2018

There Is A Fish In My Forest And Other Post-Timber War Musings, Mike Miles

Humboldt Journal of Social Relations

(none)


Finding Solutions Through Politics: One View From Inside The Timber Wars, Erin C. Kelly, Andrea Tuttle May 2018

Finding Solutions Through Politics: One View From Inside The Timber Wars, Erin C. Kelly, Andrea Tuttle

Humboldt Journal of Social Relations

There are many perspectives of the timber wars, and one perspective that is not frequently documented is that of government bureaucrats – policy makers, regulators, and others who were often caught in the crossfire of opposing sides. This oral history with Dr. Andrea Tuttle is one attempt to describe the Timber Wars from this perspective. On February 25, 2017, I invited Dr. Tuttle to sit down and discuss her history with forest regulation. I asked very few questions and instead listened as she told the history; I ended up with two hours of audio, which I transcribed to over fifteen …


Timber Wars And Aftermath In Northwest Coastal California, Richard Gienger May 2018

Timber Wars And Aftermath In Northwest Coastal California, Richard Gienger

Humboldt Journal of Social Relations

Abstract and other info uploaded below


There Has Never Been A 'Timber War', Greg King May 2018

There Has Never Been A 'Timber War', Greg King

Humboldt Journal of Social Relations

There has never been a 'timber war' in northwestern California, but rather premeditated and ongoing attacks against the forests, and against the people who would protect them. This paper provides a historic examination of redwood logging and protection efforts since 1850.


Introduction To Hjsr Special Issue 40: The American West After The Timber Wars, Erin C. Kelly, Yvonne Everett May 2018

Introduction To Hjsr Special Issue 40: The American West After The Timber Wars, Erin C. Kelly, Yvonne Everett

Humboldt Journal of Social Relations

No abstract provided.


Table Of Contents May 2018

Table Of Contents

Humboldt Journal of Social Relations

No abstract provided.


Utility-Scale Solar Photovoltaic Hosting Potential Of Historic Mill Sites In Humboldt County, California, Michael Avcollie Jan 2018

Utility-Scale Solar Photovoltaic Hosting Potential Of Historic Mill Sites In Humboldt County, California, Michael Avcollie

Cal Poly Humboldt theses and projects

The adoption of Redwood Coast Energy Authority’s (RCEA’s) Community Choice Energy program in May of 2017 across Humboldt County has sparked interest in locally produced energy from solar photovoltaics (PV). RCEA has a goal of bringing 5 Megawatts (MW) of local, utility-scale, solar PV under contract by 2018 and 15 MW by 2023. Humboldt County’s former mill sites offer features that make them suitable for hosting PV development. This study performed an inventory and analysis of these sites to answer two questions: Can Humboldt County’s former mill sites provide the hosting capacity for15 MW of local, utility-scale solar PV? Which …


Low Income Housing Energy Efficiency Improvement Program For The Yurok Tribe Of Northern California, Keivan Branson Jan 2018

Low Income Housing Energy Efficiency Improvement Program For The Yurok Tribe Of Northern California, Keivan Branson

Cal Poly Humboldt theses and projects

Housing on the Yurok reservation in California is a major concern for the local Tribal Government. This report details a study of the energy situation for housing of the Yurok Tribe to provide a framework for implementing housing energy efficiency to benefit low-income members of the Tribal community residing in substandard housing. The report briefly details the history of the reservation as it pertains to the current housing situation, as well as the authors personal context of living for 16 years in the reservation town of Klamath, CA. The analysis draws on information obtained from mixed methods, including information collected …