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Full-Text Articles in Natural Resources Management and Policy

Using Environmental Dna Methods For Estimating Juvenile Chinook Salmon Abundance, Jacqueline Marie Bridegum Jan 2024

Using Environmental Dna Methods For Estimating Juvenile Chinook Salmon Abundance, Jacqueline Marie Bridegum

Cal Poly Humboldt theses and projects

In the Central Valley of California, stocks of Chinook Salmon are declining, and two out of the four ecotypes of Chinook Salmon within the Sacramento River system are federally listed. A monitoring network has been developed to estimate the abundances of downstream migrating Chinook Salmon smolts, but there is high uncertainty in these estimates due to low catch rates. Environmental DNA (eDNA) monitoring, which involves capture of genetic material that organisms release into their surrounding environment, has shown promise for estimating abundance of salmonids and could complement existing monitoring efforts and potentially reduce uncertainty in abundance estimates. This research project …


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 …


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 …


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 …


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 …


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 …


Assessing Spatio-Temporal Patterns Of Forest Decline Across A Diverse Landscape In The Klamath Mountains Using A 28-Year Landsat Time-Series Analysis, Drew S. Bost Jan 2018

Assessing Spatio-Temporal Patterns Of Forest Decline Across A Diverse Landscape In The Klamath Mountains Using A 28-Year Landsat Time-Series Analysis, Drew S. Bost

Cal Poly Humboldt theses and projects

Rates of tree mortality in California and the Pacific Northwest have greatly increased in recent years, driven largely by pest and pathogen outbreaks as well as the effects of hotter, warmer droughts. While there have been a multitude of regional-scale assessments of mortality and forest decline, landscape-level studies are necessary to better identify forests that are most vulnerable to decline and to anticipate future changes. This need is particularly notable in the remote and little-studied mountains of northwest California, which are renowned for their diverse, heterogeneous vegetation types. A recent observation of elevated levels of Shasta red fir (Abies …


Post-Fire Regeneration And Fuel Succession Patterns In Hesperocyparis Bakeri Forests, Bret Anthony Mcnamara Jan 2018

Post-Fire Regeneration And Fuel Succession Patterns In Hesperocyparis Bakeri Forests, Bret Anthony Mcnamara

Cal Poly Humboldt theses and projects

Climate change is predicted to cause widespread redistribution of suitable tree habitats, as well as increase the size and frequency of wildfires in the western United States during the forthcoming century. Rare serotinous conifers may have heightened sensitivity to the impacts of both fire regime and climate shifts for multiple reasons. First, the rapid spatial rearrangement of suitable habitat will disproportionately affect trees with constrained seed dispersal capabilities, and limited dispersal is a trait associated with some genera of serotinous trees. Second, a number of serotinous conifers depend on fire disturbances for regeneration, though with the expected increase in annual …


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 …


The Water-Electricity Nexus In California: Drought-Induced Risk To Thermal Electricity Generation, Timothy S. Hyles Jan 2017

The Water-Electricity Nexus In California: Drought-Induced Risk To Thermal Electricity Generation, Timothy S. Hyles

Cal Poly Humboldt theses and projects

Investigating the possibility that drought might limit the water supply needed for thermal electricity generation in California, power plant water consumption data was compared to urban and agricultural consumptive demands to identify areas where power plants might contribute to regional water stress. To identify areas where power plants might be impacted by water stress, regional power plant, urban, and agricultural water demands were also compared to the available water supply. A list of power plants that would contribute most to regional water scarcity (individually and in aggregate) was highlighted, based on the plant’s water consumption volume, water-intensity, and water source. …


Juvenile Survival And Adult Return As A Function Of Freshwater Rearing Life History For Coho Salmon In The Klamath River Basin, Molly Gorman Jan 2016

Juvenile Survival And Adult Return As A Function Of Freshwater Rearing Life History For Coho Salmon In The Klamath River Basin, Molly Gorman

Cal Poly Humboldt theses and projects

The Scott and Shasta rivers, Klamath River tributaries, experience spatial disparity in habitat quality in spring and summer as a result of historical and current land-use. Juvenile Coho Salmon (Oncorhynchus kisutch) born in the upper tributary reaches often rear in natal streams before migrating to sea. However, those born in the lower reaches often encounter unsuitable habitat and emigrate during their first spring to seek non-natal rearing habitats. It is assumed that these early outmigrants are population losses. This study evaluated first-summer survival, and contribution to the adult population, of non-natal rearing juveniles in the Klamath River Basin. …