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Full-Text Articles in Physical Sciences and Mathematics

Finding Nondestructive Parameters For Root-To-Shoot Ratios In Douglas-Fir, Grand Fir, And Redwood Saplings In Northwest California For Biomass And Carbon Storage Estimates, Walter A. Kast Jan 2017

Finding Nondestructive Parameters For Root-To-Shoot Ratios In Douglas-Fir, Grand Fir, And Redwood Saplings In Northwest California For Biomass And Carbon Storage Estimates, Walter A. Kast

Cal Poly Humboldt theses and projects

ABSTRACT

FINDING NONDESTRUCTIVE PARAMETERS FOR ROOT-TO-SHOOT RATIOS IN DOUGLAS-FIR, GRAND FIR, AND REDWOOD SAPLINGS IN NORTHWEST CALIFORNIA FOR BIOMASS AND CARBON STORAGE ESTIMATES

Walter A. Kast

There is a need for better understanding of how woody biomass is allocated above and belowground and how this allocation might differ among tree species. In this field of research, investigators face challenges such as the laborious task of removing trees from the soil with destructive sampling, and the cleaning, drying, and weighing of belowground biomass (BGB). Therefore, researchers and practitioners most often rely on existing models to predict BGB from easily-measurable aboveground variables …


Multiscale Habitat Suitability Modeling For Canary Rockfish (Sebastes Pinniger) Along The Northern California Coast, Portia N. Saucedo Jan 2017

Multiscale Habitat Suitability Modeling For Canary Rockfish (Sebastes Pinniger) Along The Northern California Coast, Portia N. Saucedo

Cal Poly Humboldt theses and projects

Detailed spatially-explicit data of the potential habitat of commercially important rockfish species are a critical component for the purposes of marine conservation, evaluation, and planning. Predictive habitat modeling techniques are widely used to identify suitable habitat in un-surveyed regions. This study elucidates the predicted distribution of canary rockfish (Sebastes pinniger) along the largely un-surveyed northern California coast using data from visual underwater surveys and predictive terrain complexity covariates. I used Maximum Entropy (MaxEnt) modelling software to identify regions of suitable habitat for S. pinniger greater than nine cm in total length at two spatial scales. The results of …


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. …


A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London Jan 2017

A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London

Cal Poly Humboldt theses and projects

Intermittent streams are common throughout the world and comprise 60% or more of total river lengths in the conterminous United States. Despite their prevalence, intermittent streams are understudied, particularly first-order headwater streams, which are vital for maintaining the function, health and biotic diversity of river networks. In June 2016, I sampled five intermittent and five perennial headwater streams in the Mattole River watershed in northwestern coastal California, USA, to compare benthic macroinvertebrate (BMI) assemblages between intermittent and perennial streams. BMI samples were collected using a 500µm mesh D-net at eight randomly located riffles along a 150-m reach, and then composited, …


Forward Osmosis For Wastewater Treatment And Energy Recovery: A Techno-Economic Analysis, Patrick William Buckwalter Jan 2017

Forward Osmosis For Wastewater Treatment And Energy Recovery: A Techno-Economic Analysis, Patrick William Buckwalter

Cal Poly Humboldt theses and projects

A novel wastewater treatment system was investigated using forward osmosis membranes to treat municipal wastewater. Treatment by forward osmosis was determined to cost $10 million per million gallons per day (MGD) of wastewater capacity over a 20-year lifetime, with an energy consumption of 870 kWh per million gallons. A case study at the Arcata Wastewater Treatment Plant was conducted to investigate a treatment system that combines energy recovery from algae biomass with forward osmosis membrane treatment using local seawater as a draw solution. Total system cost was calculated to be $29.7 million over a 20-year lifetime with a 2.3 MGD …


The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry Jan 2017

The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry

Cal Poly Humboldt theses and projects

Many amphibian species are in decline due to habitat loss and changing climates. Understanding how habitat characteristics and climate influence vital rates, and if they act in concert or in opposition can inform management decisions. This study investigated the potential interaction of canopy cover and climate on early stage vital rates of northern red-legged frogs. Demographic data were collected from sample populations in experimental canopy cover treatments across a latitudinal distribution. Rearing cages were used to estimate hatch success, and mark-recapture surveys to estimate tadpole survival. Ambient air temperature was used as an index of climate because it is easily …


Sedimentation And Erosion Patterns Within Anabranching Channels In A Lowland River Restoration Project, Ivan Medel Jan 2017

Sedimentation And Erosion Patterns Within Anabranching Channels In A Lowland River Restoration Project, Ivan Medel

Cal Poly Humboldt theses and projects

Phase 2A of the Salt River Ecosystem Restoration Project (SRERP) was implemented to increase transport efficiency of water and sediment through a low gradient river reach to alleviate flooding on adjacent properties. The SRERP utilizes a unique anabranching channel design that concentrates base flows within a single deep, narrow channel overflowing onto an alternating series of higher elevation active benches at flood stages. This paper investigated the performance of the project’s hydraulic conveyance and general utility of anabranching channels as a restoration alternative by assessing the distribution and magnitude of deposition and erosion response patterns.

Aggradation was not observed within …


A Population Model For Coho Salmon (Onchorhynchus Kisutch) In Freshwater Creek: Evaluating The Effects Of Life History Variation And Habitat Restoration, Gabriel Scheer Jan 2017

A Population Model For Coho Salmon (Onchorhynchus Kisutch) In Freshwater Creek: Evaluating The Effects Of Life History Variation And Habitat Restoration, Gabriel Scheer

Cal Poly Humboldt theses and projects

Historic land use practices and associated habitat degradation have led to significant declines in coho salmon (Oncorhynchus kisutch ) populations across their range. In California they are a state and federally listed species, requiring population monitoring and management plans tailored towards recovery. Traditionally, juvenile coho salmon in California were thought to spend approximately one year in their natal freshwater habitats before migrating to sea the following spring and summer as smolts. However, recent work has documented considerable variation in juvenile life history and migration timing. Specifically, juveniles that migrate downstream prior to one year of age and spend their …