Wavelet analysis is an analytical and modeling tool for optimizing sampling efficiency and accuracy, particularly in the context of designing long-term, large-scale monitoring plans. As a pattern analysis method that accommodates and preserves non-stationarity, wavelet analysis provides novel visualization and analytical capabilities for increased insight into interactions between multi-scalar heterogeneous...
This dissertation has focused on the charateristics of bubbles generated by breaking waves and the feedback of wave-current interaction on the forcing mechanism of low frequency wave especially basin seiching wave. For the first study, Optical image capture observations of breaking waves in a laboratory surf zone are presented. The...
The U.S. Pacific Northwest is home to one of the most extreme wave climates in the world with waves of 10 m in height arriving to the coast approximately each year. With an average water temperature of 12℃, the beaches in the region are too cold to go on a...
A theory is developed to provide an analytical solution to an
unsteady flow field which is partially occupied by a porous structure.
The flow is induced by a small amplitude incident wave
train. The porous structure may contain multi-layer anisotropic but
homogeneous media. Three typical porous structures are investigated:
a...
Realizing the vast amount of energy available in ocean waves, an industry has emerged that is progressing towards the deployment of grid–connected wave energy converters. Likely to be deployed in arrays, a challenge to the wave energy industry is maximizing the energy production of such arrays. We have been developing...
Knowledge about vegetation patterns and ecological processes in unmanaged, late-successional
watersheds is needed to provide a foundation for forest management strategies
aimed at conserving native biodiversity. I examined influences of environmental variability
and disturbance history on forest structure and composition in the Cummins Creek
Wilderness, located on the central Oregon...
Western juniper (Juniperus occidentalis) encroachment has been associated with increased soil loss and reduced infiltration resulting in the loss of native herbaceous plant communities and the bird and animal species that rely on them. Hydrologically, however, change in water yield has been linked with the amount of annual precipitation a...
Oregon's watershed councils are local, non-regulatory, collaborative forums charged
with the recovery of endangered salmon and improving water quality under The Oregon Plan for Salmon and Watersheds. Private forest landowners, given their prominence is owning riparian areas, are central to success of these efforts. Using a statewide survey of watershed...
Problem areas identified are: The needs a) to develop curve
fitting procedures to estimate flood flow distributions; b) to
incorporate precipitation data into frequency analysis procedures;
and c) to better define flood potentials for ungauged streams.
Closely related to the above, it is noted that variables commonly
used to estimate...
Research on the application of soluble, metal chelates for
water tracing using thermal neutron activation analysis for tracer
determination has led to the development of several tracers with
promising solution stabilities (conservative behavior) and determination sensitivities. The solution stabilities of the ethylenediamine
tetraacetic acid (EDTA) and the diethylenetriamine pentaacetic acid...
Red alder (Alnus rubra Bong.) seedlings fertilized with NH4NO3 or inoculated with a pure culture Fran/cia and inoculated with live or dead spores of the mycoirhizal fungus Alpova diplophloeus (Zeller & Dodge) Trappe & Smith were grown in a growth
chamber or in a greenhouse for six months Frankia inoculation...
Application of sewage sludge to soils increases the trace metal
content and the organic content of soils. The complexation of indigenous and added metals with organic constituents must be studied to
evaluate metal availability to plants and animals.
The water soluble organic fractions (WSOF) from an agricultural
soil (W), a...
Multipurpose management of hydrosystems face a number of uncertainties related to hydrologic variability and nonstationarity. Anticipated air temperature increases in the Pacific Northwest region are projected to alter the timing and quantity of streamflow associated with precipitation shifting from snow to rain, including shorter winter runoff periods, earlier spring runoff,...
The overall objective of the study is to measure changes in agricultural production and water use patterns under various water supply and allocation mechanisms. The methodology nests an economic model of on-farm decisions in a basin-wide hydrologic model. The economic model forecasts the use of applied water, technology and crop...
The age, or residence time of water is a fundamental descriptor of catchment hydrology, revealing information about the storage, flow pathways and source of water in a single integrated measure. While there has been tremendous recent interest in residence time to characterize catchments, there are few studies that quantify residence...
Sorbitol-induced osmotic stress (SIOS) to the root was found to be effective in
reducing transpirational water loss in plants during water stress. Mechanisms of SIOS in
stomatal control were investigated in containerized apples (Malus domestica Borkh.
'Gala'/M26) when leaf water potential (Ψw), osmotic potential (Ψs), turgor potential (Ψp),
stomatal conductance...
Chapter 1 Growth and Survival of Root-Wrenched Douglas-fir Seedlings Root wrenching of seedlings (severing the roots 15 cm below the soil surface) was investigated as a nursery practice to improve growth and survival of field-planted Douglas-fir from six local seed sources
in the Pacific Northwest. At lifting, shoots of wrenched...
The goal of this thesis was to determine the physiological mechanisms that link adverse preplanting treatments of Douglas-fir, such as exposure and root pruning, to the phenomenon of transplanting shock. The objective of experiments 1 and 2 was to measure the effect of exposure and pruning on the physiology and...
Both red (Trifolium pratense L.) and white (Trifolium repens L.) clover
seed yields can be highly variable and low in western Oregon. The objectives of
this study were to: i) determine crop water requirements and supplemental
irrigation timing, and ii) quantify the effects of soil and water status on
inflorescence...
Significant post planting mortality of young conifer seedlings often occurs on drought prone sites because seedlings fail to either establish, or maintain favourable water relations. Survival is contingent upon growth which occurs when turgor pressure is above a threshold level. Since growth after planting is influenced by nursery cultural practices,...
Dormancy of 'Pinot Noir' grapevines was characterized. Primary buds
required ca 300 cumulative chilling hours (CCH) to initiate the transition from
endodormancy to ecodormancy, which occurred in mid November. Additional
chilling, up to 1000 CCH, improved budbreak. Changes in bud water content
were estimated by gravimetric and spectroscopic methods. Total,...
The Pacific Northwest region of the United States is known for quality production of blueberries, blackberries, and red raspberries. However, as the climate shifts to warmer, drier, and more extreme summers, growing these water intensive berry crops is becoming increasingly difficult. Furthermore, water regulations within agriculture are becoming more prevalent...
The North Unit irrigation District of Central Oregon,
a water project developed under the guidelines of the
Bureau of Reclamation, is characterized by limited water
and the need for efficient utilization and control of the
irrigation system. To manage the limited water resource,
irrigators need a timely and economical method...
There is no information available on water management of birdsfoot
trefoil grown for seed. Information is also not available describing how to
minimize seed losses due to shattering in order to obtain consistently high
birdsfoot trefoil seed yields. The objectives of this research are to: (i) quantify
crop water use,...
Academics and practitioners agree that in water governance, the quality of a decision making process should influence the quality of the outcome and the degree to which it is accepted by interested parties. However, finding a feasible way to evaluate and then improve the quality of a decision making process...
Exercise may be the most effective strategy to reduce osteoporotic fractures in older adults because of its potential to reduce both bone loss and fall risk. It is unclear whether water exercise is an effective strategy to reduce fracture risk in postmenopausal women. PURPOSE: To examine the effects of a...
Urban landscape water use is increasingly a focus of water conservation efforts. This is especially true in the arid and semi-arid regions of the western United States where increased demand, environmental concerns, and extended periods of drought have created chronic water shortages. However, until recently, little attention has been paid...
Water conservation and water quality are rapidly increasing in importance in all areas of the world. The ability to accurately measure soil water content and salinity, over a wide variety of conditions, is key to meeting this need. A set of forward prediction models and waveform interpretation algorithms to extract...
Sandy soils are among the least productive soils because of their inability to
store adequate water for plant growth. Their high percolation rate not only allows
water to move quickly beyond the root zone, but also washes nutrients below the reach
of plant roots. High evaporation occurs from the soil...
Drought and mandatory water restrictions are limiting the availability of irrigation water in many important blueberry growing regions and new strategies are needed to maintain yield and fruit quality with less water. Three potential options for reducing water use, including deficit irrigation, irrigation cut-offs, and crop thinning, were evaluated for...
Experiments were carried out to study the movement of water and
halide anions in perched water tables or saturated zones in the soil
and upper rock mantle of eight different experimental sites located
on low hills near the western border of the Willamette Valley. At each
site the experimental procedure...
Microbial ecology has been transformed by metagenomics, the study of the genetic in-formation in entire communities of organisms. In the following we develop metagenomic tools arising from the classic Wasserstein metric as applied to questions regarding the diversity between microbial communities. We provide a novel proof of the characteriza-tion of...
Approximate string matching is commonly used to align genetic sequences (DNA
or RNA) to determine their shared characteristics. In contrast with the standard
dynamic programming methods which use local edit distance models, the Walking
Tree heuristic method was created to handle non-local changes, e.g., translocations,
inversions, and duplications, altogether and...
Earthquakes a . tsunamis pose significant threats to port and harbor
communities in the Pacific Northwest. Developing effective mitigation and
preparedness plans requires a comprehensive understanding of community
vulnerability. Research presented here focuses on the vulnerability of ports and
harbors to earthquake and tsunami hazards and includes a regional study...
Realistic (ideally photorealistic) real-time rendering has remained an elusive goal in computer graphics. While photorealistic rendering has certainly been achieved at the expense of tremendous computational resources and corresponding rendering times; real-time rendering typically must accept a great number of compromises to achieve adequate performance, such as aliasing artifacts, the...
Vortical structures are the driving mechanism of transition to turbulence in porous media requiring adequately resolved observations along with analysis of the scale and energy of flow within the pores. Of specific interest is to understand the vortex dynamics, energy, and turbulent mixing and transport properties in the scale of...
The volumetric receiver is an advanced solar central receiver
concept designed to produce high temperature air. This document
presents the results of a heat transfer and performance evaluation of
the volumetric receiver concept.
The volumetric receiver consists of an array of ceramic fins or
fibers arranged in concentric rows around...
The awareness of electric power quality has increased over the past decade as electronic equipment
has become more susceptible to power disturbances. The most disruptive power disturbances are voltage
sags and momentary interruptions and their effect on adjustable speed drives (ASDs) is studied in this
thesis.
Several solutions have been...
The Rattlesnake Ash-Flow Tuff erupted 7.05±0.01 Ma from the western Harney Basin, southeastern Oregon. The location of the vent area is inferred based on vent-ward increases in size of pumices, in degree of welding, and in degree of post-emplacement crystallization. Today's outcrops cover 9000 km2 and estimated original outcrop coverage...
The global mid-ocean ridge system is the largest magmatic system encompassing over 75% of the Earth’s total volcanism. As magmas ascend through the vertically variable oceanic crust, melts begin to crystallize and diversify and subsequently erupt at the surface. The interpretation of these erupted products observed on the seafloor requires...
Semi-volatile trace metals like Li, Cu, Mo, Sn, In, and Pb have the potential to track mobility of a volatile phase in volcanic systems. In this dissertation four studies are presented that either directly investigate or are motivated by observations of trace metal behavior in volcanic systems. A common tool...
High vegetative growth of Pinot Noir vine is a common problem in most vineyards of Oregon's Willamette Valley, where sunlight exposure and heat accumulation are limited. Consequently, growers in this region commonly use vineyard management strategies to regulate vine vigor and improve grape and wine quality. Wine quality is greatly...
Two-phase flow in a fractal-like branching microchannel heat sink may have
enhanced heat transfer capabilities over single phase flow in the same branching
channel network. In order to exploit this potential, a complete understanding
of flow boiling in this geometry is required. The fractal-like geometry is similar
to that of...
Community colleges have become a practical educational option for undocumented students seeking an associate degree; thus reflecting the community college's very mission and purpose by providing access and affordability for these students. Specifically, undocumented Latino students are known to select community colleges due to their low tuition cost, proximity to...
The purpose of this study was to describe and record the experiences of people of color in a community leadership development program. Selected people of color were asked to describe their experiences as participants in the American Leadership program in Tacoma-Pierce County in the State of Washington. The American Leadership...