Biodiversity loss is of global concern, and is due in part to deforestation and high consumer demand for wood and wood products. The neotropical tree species Cedrela odorata (“Spanish cedar” or “cedro”) is economically valuable for its wood and faces threats of overexploitation. Due to strong similarities in wood features...
The climate of the Pacific Northwest is in flux, and existing forest ecosystems are stressed and poised to shift in fundamental ways, with or without human intervention. This dissertation probes the nature of forest responses to environmental change through investigations of morphology and genetics of three species of alder co-occurring...
At a time when the biodiversity on Earth is being rapidly lost, new technologies and methods in genomic analysis are fortunately allowing scientists to catalog and explore the diversity that remains more efficiently and precisely. The studies in this dissertation investigate genomic diversity within the milkweed genus, Asclepias, at multiple...
Fungi play critical roles in ecosystem processes and interact with plant communities in mutualistic, pathogenic, and commensal ways. Fungal communities are thought to be influenced by both associated tree communities and soil properties. However, the relative importance of the biotic and abiotic drivers of soil fungal community structure and diversity...
Rhizopogon is a large genus of ectomycorrhizal (EM) fungi that grows in association with host trees of the family Pinaceae. We have conducted a series of studies investigating the ecology and evolutionary biology of the EM symbiosis shared between R. subgenus Villosuli and trees of the genus Pseudotsuga. Two members...
In recent years, there has been renewed interest in black raspberry (Rubus
occidentalis L.) breeding. This has been spurred, in part, by an increase in black
raspberry consumption due to studies that have shown them to be particularly high in
anthocyanin content indicating high levels of antioxidants. Present cultivars are...
North America, with over 400 species of Astragalus (Fabaceae), is one of three major centers of diversity, all of which comprise the majority of the nearly 1750 species of Astragalus worldwide. One of the most diverse species, Astragalus lentiginosus of Section Diphysi, is a polymorphic complex of over 40 varieties,...
Veratrum californicum (common name: corn lily) is a wild plant species that grows in the Intermountain West, its range extending from British Columbia to Mexico. Corn lily is of interest because it has the potential to provide pharmaceutical precursors for use in the treatment of cancer. Pharmaceutical companies are currently...
An estimated 5.7 million Americans are currently living with the dementia stage of Alzheimer’s disease, impeding health and wellbeing for individuals diagnosed, caregivers, families, and communities across the country (Alzheimer’s Association, 2018). Studying early indicators of age-related cognitive decline and pathological cognitive impairment (e.g., Alzheimer’s disease) is crucial to inform...
This paper is a summary of a larger project that consolidated
agricultural land use projection information for the Pacific Northwest,
as of January 1979. The characteristics of nine major projection studies
are identified and used as a basis for comparing the relative merits of
each study with regard to: 1)...
The objective of the study is to analyze empirically the demand
for hired farm labor and the elasticities of substitution of capital for
labor in the U.S., the Middle Atlantic region, the Pacific region, and
in the states of California and Oregon.
The data period 1941-1969 was analyzed for the...
A novel high temperature thermal instrument is proposed, which utilizes a dual-sensing platinum resistor encased in a mono-crystalline alpha-alumina (sapphire) substrate. The instrument is comprised of four platinum trace elements, oriented with 90° rotational symmetry atop a 1120 oriented crystal lattice substrate. All four of these sensors measure temperature directly...
In this study, we contrasted socioemotional selectivity theory (SST;
Carstensen, 2006) with dynamic integration theory (DIT; Labouvie-Vief, 2003) using
trajectories of quantitative and qualitative social support in later life. SST is a lifespan
theory of motivational development (Carstensen, Isaacowitz, & Charles, 1999). There
is a normative decline in social support...
Adequate management and scientific investigation of ecosystems
depends on classification of landscape systems based on all significant
bio-physical and associated cultural properties. The present
classification is a hierarchical systems design that can be modeled in
terms of a natural system interacting with its level-specific
environment. A watershed system in this...
Juvenile English sole (Parophrys vetulus) were
collected in Yaquina Bay, Oregon from January, 1986 to
March, 1987. Recruitment of young-of-the-year sole
occurred from January to June, 1986 and again from
December, 1986 to February, 1987. Emigration from Yaquina
Bay started in September, 1986, but a small portion of the
English...
This study was prompted by the need for improving the efficiency of irrigation systems at the Oregon South coastal areas. Accurate information about evapotranspiration (ET) rates is essential for maximizing the efficiency of irrigation systems. Currently, ET estimates provided by Bureau of Reclamation AgriMet Program are derived from the Kimberly...
Cognitive self-regulation and the behavioral manifestations of cognitive self-regulation are important aspects of school readiness, yet less is known about the variation in measurement modalities within children. In this dissertation, two studies examined the makeup, antecedents, and consequents of constellations of cognitive self-regulation (CSR) measures around the transition to formal...
Whitebark pine (Pinus albicaulis) is an iconic North American high-elevation tree species currently threatened by climate change, mountain pine beetle, and white pine blister rust (WPBR), a lethal disease caused by the non-native fungal pathogen Cronartium ribicola. In collaboration with the USDA Forest Service Dorena Genetic Resource Center, germplasm was...
As part of investigations to adapt a suitable grazing system in
western Oregon, this research was designed to monitor the effects of
defoliation treatments on dry matter production, forage quality,
regrowth after defoliation, and species composition of a Lolium
perenne Trifolium subterraneum pasture for three consecutive
growing seasons from 1980...
Three commercial sausage starter cultures were grown in
an internal-pH-controlled medium (PHASE 4) and in a soluble
phosphate-buffered medium. The cultures were tested by
comparing viable counts before and after freezing at -40 C
or freeze-drying and subsequent storage for 3 months in the
frozen or dried state. Strains varied...
The goal of this study was to determine if the cardiorespiratory adaptations to an eight-week circuit weight training program are better measured with a biokinetic swim-bench test versus a standard treadmill test. The working hypothesis of the study was that since standard circuit weight training programs stress the upper body...
Coal continues to be burned by direct combustion in packed or moving bed in
small size domestic furnaces, medium size industrial furnaces, as well as small power
stations. Recent stringent restrictions on exhaust emissions call for a better
understanding of the process of combustion of coal in beds.
The present...
This investigation demonstrates the feasibility of a
polyculture system using effluent water from land-based
salmon culture systems to feed juvenile Manila clams, Tapes
japonica (Deshyes), and an evaluation of an artificial diet
for feeding juvenile clams. An economic analysis of the
polyculture system was compared to cultures of a single...