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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The organization of a library for the John Gill Elementary School, Redwood City, California

Hutcheon, Ian Loring 01 January 1957 (has links)
Statement of the Problem: The objectives of this thesis are to set forth the detailed procedures and methods essential to organize, from the instructional point of view, a library for John Gill School, a kindergarten through sixth grade school.
12

Validation of a Redwood Sequoia Sempervirens (D. Don) Endl Butt Log Sawing Simulator

Ashford, Sheridan January 2013 (has links)
Redwood (Sequoia sempervirens (D. Don) Endl.) has been identified as a species with considerable potential for plantation forestry in New Zealand. Investment decisions in high value alternate species must be based on accurate wood quality and value predictions. There is an opportunity to extend non-destructive evaluation tools available to redwood growers, and to present the outputs of the growth model by log products and sawn timber. A redwood pruned buttlog sawing simulator has been developed however the simulator had not been tested with real data. Twelve redwood trees from Mangatu estate were selected for a sawing study; these logs were reconstructed and run through the sawing simulator. Computerised log processing was used to produce simulated pruned log sawing outturn from the redwood Buttlog Sawing Simulator, and results were compared to real results from a sawing study. The objective of the study was therefore to determine how well the simulator matched volume and grade out-turn from twelve logs. This study found the many inconsistencies between simulated data and real data; particularly related to log size. While this study was unsuccessful in validation of the redwood sawing simulator, it provides initial insight into the simulators strengths and short comings.
13

Height-associated variation in leaf anatomy of tall redwoods : potential impacts on whole-tree carbon balance /

Oldham, Alana Rose. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2008. / Includes bibliographical references (leaves 29-34). Also available via Humboldt Digital Scholar.
14

The effect of overstory canopy density alterations on air temperature in a managed redwood forest /

Wilson, Elizabeth F. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 25-27). Also available via Humboldt Digital Scholar.
15

Fire History and Soil Carbon in Old Growth Coast Redwood Forests across the Late Holocene

Hayes, Katherine 06 September 2018 (has links)
Fire is an important ecological feature across temperate forests, yet characteristics of the coast redwood fire regime remain uncertain due to generally few fire histories. This study examines legacies of fire in redwood forests in northern California through radiocarbon dating and quantification of soil macro-charcoal, soil carbon and pyrogenic carbon in old growth redwood stands. We sampled soils in the Headwaters Forest Reserve, a protected fragment of old growth redwood in Humboldt County, California. Radiocarbon dates from macro-charcoal indicate fire events occurring a maximum of 6,840 calibrated years BP, predating existing records. Composite 14C dates show increased fire activity within the last 1,000 years in synchrony with existing dendrochronological records. Soil C averaged 928 g/m2, of which a high proportion was pyrogenic C (15-30%). Information from this multi-proxy reconstruction clarifies our understanding of the nature of coast redwood fires, contributing to ongoing discussions of coast redwood fire management.
16

Classification of Plot-Level Fire-Caused Tree Mortality in a Redwood Forest Using Digital Orthophotography and Lidar

Bishop, Brian David 01 March 2014 (has links)
Swanton Pacific Ranch is an approximately 1,300 ha working ranch and forest in northern Santa Cruz County, California, managed by California Polytechnic State University, San Luis Obispo (Cal Poly). On August 12, 2009, the Lockheed Fire burned 300 ha of forestland, 51% of the forested area on the property, with variable fire intensity and mortality. This study used existing inventory data from 47 permanent 0.08 ha (1/5 ac) plots to compare the accuracy of classifying mortality resulting from the fire using digital multispectral imagery and LiDAR. The percent mortality of trees at least 25.4 cm (10”) DBH was aggregated to three classes (0-25, 25-50, and 50-100%). Three separate Classification Analysis and Regression Tree (CART) models were created to classify plot mortality. The first used the best imagery predictor variable of those considered, the Normalized Difference Vegetation Index (NDVI) calculated from 2010 National Agricultural Imagery Program (NAIP) aerial imagery, with shadowed pixel values adjusted, and non-canopy pixels removed. The second used the same NDVI in combination with selected variables from post-fire LiDAR data collected in 2010. The third used the same NDVI in combination with selected variables from differenced LiDAR data calculated using post-fire LiDAR and pre-fire LiDAR collected in 2008. The imagery alone was 74% accurate; the imagery and post-fire LiDAR model was 85% accurate, while the imagery and differenced LiDAR model was 83% accurate. These findings indicate that remote sensing data can accurately estimate post-fire mortality, and that the addition of LiDAR data to imagery may yield only modest improvement.
17

Importance and Spatial Distribution of Phytophthora Ramorum Host Species in a Coast Redwood Forest

Gray, Alicia E. 05 1900 (has links)
Phytophthora ramorum, an exotic forest pathogen known as ‘sudden oak death’ (SOD), has received considerable attention in recent years because of its effects on vegetation structure, composition, and fire disturbance regimes in western U.S. coastal forests. This research examines differences in the importance (e.g., density, dominance, and frequency) and distribution of five host species of P. ramorum–– Umbellularia californica (California bay laurel), Quercus agrifolia (coast live oak), Pseudotsuga menziesii (Douglas fir), Sequoia sempervirens (Coast redwood), and Arbutus menziesii (Madrone)––in Soquel, California. A stratified random sampling design was used to select 66 plots surrounding a managed forest edge in Soquel Demonstration State Forest. Vegetation measurements were conducted in summer 2013. In each plot, all trees ≥3 cm diameter at breast height (DBH) were identified to species, counted, and DBH, height, and canopy position measured. Leaf area index (LAI) of bay laurel was measured to quantify the amount of leaves available for pathogen dispersal with a LiCOR 2200 Plant Canopy Analyzer. In addition, morning (9:00 am) and afternoon (1:00 pm) photosynthetically active radiation (PAR) were quantified using a quantum light sensor. This paper examines the influence of environmental variables, including distance to edge, aspect, slope, and light availability on host species spatial patterns in Soquel, CA. Studying P. ramorum host pattern and importance among managed forest edges is critical for determining hotspots most susceptible to infection and spread, thus relevant for implementing control measures.
18

Power V. Threhsold: Near-Channel Morphology Controls Sediment Rating Curve Shape in Coastal Redwood Watersheds

Fisher, Adam Caspian Nebraska 01 December 2019 (has links)
River sediment is one of the most pervasive pollutants in the world. Excess amounts of fine sediment can reduce water quality, damage stream ecosystems, and harm aquatic life. Both natural and human-caused processes can add sediment to a river, such as tectonic uplift, landslides, and timber harvesting. Therefore, it is important to understand how fine sediment enters and moves through a rive system to inform policymakers and land-managers on effective ecosystem management. In this study, we determined how the relationship between river flow and suspended sediment changed among watersheds along the North Coast of California. We found a rise in suspended sediment concentration at median flows following extreme timber harvesting. Additionally, our results indicate that river flow and suspended sediment relationships are influenced by timber harvest activity, tectonic uplift, rainfall patterns, and near-channel environments. These results support previous findings that extreme land disturbance in a watershed, be it natural or human-caused, can change river flow and suspended sediment relationships. Our results suggest that policymakers and land-managers should take into account tectonic uplift when making regulation and should prioritize protecting near-channel environments.
19

Carbon distribution in managed upland redwood stands using the California Climate Action Registry Forest Project Protocol /

Swenson, Steven W. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2009. / Includes bibliographical references (leaves 55-65). Also available via Humboldt Digital Scholar.
20

Compounding Fire Disturbance History Encourages Coast Redwood (Sequoia sempervirens) Regeneration and Community Dominance

Brousil, Matthew R 01 December 2016 (has links)
Disturbance is fundamental to forest ecosystem function and overall health, but climate change is likely to increase both disturbance frequency and intensity in the future. Forests subject to increasingly frequent and intense disturbances are more likely to experience compounding disturbance effects. Compounding disturbances may exert unpredicted, non-additive stresses on ecosystems, leading to novel conditions that may exceed the capacity for local species to survive and regenerate. I further hypothesize that compounding disturbances could create conditions misaligned with species’ adaptations by altering physical and chemical growing conditions in forest soils, affecting forest composition, structure, and, subsequently, function for many years following disturbance. A better understanding of these remnant effects will be essential to managing and conserving coast redwood forests, which are projected to see increased frequency of fire under future climate scenarios. My objectives in this study were to quantify the effects of time-since-fire and single vs. compounding disturbances on coast redwood forest structure, composition, and regeneration dynamics and to evaluate the effects of abiotic soil qualities on post-fire regeneration. I mapped and sampled coast redwood forests burned in 1985, both 1985 and 1999, 2008, and 2013; modeled regeneration as a function of burn history, understory light, and post-fire nutrient levels; and tested redwood seed regeneration in post-fire soils in a greenhouse experiment. Forest structure, composition, and regeneration following compounding disturbance were most similar to the homogenous, redwood-dominated forest of the recent 2013 burn. There were no unique effects of compounding disturbance on soil nutrient levels, although variations in nutrient levels generally followed patterns seen in previous studies. Soil nitrate was positively associated with coast redwood regeneration levels, showing that soil nutrients may be influential in regeneration processes following disturbance. Time since burn and single burn histories were negatively associated with regeneration levels in the field, and there were no differences in seed germination in the greenhouse between soils from different fire histories. Increases in coast redwood forest dominance accompanied declines in bay laurel and tanoak presence, indicating a shift in post-fire forest structure and composition resulting from compounding disturbance. These results illustrate a complex relationship between regeneration dynamics, post-fire soil quality, and disturbance histories. Forest homogenization from compounding disturbances may have negative implications for ecosystem services and overall function if compounding disturbances are more frequent as predicted under future climate conditions.

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