The work presented here is focused on applying basic principles of solid-state chemistry to the study and development of new wide band-gap semiconductors and insulators for photovoltaic and electronic-device applications. Analysis of crystal structure, band structure, optical band gap, morphology and transport properties provides fundamental insight into materials performance as...
Studies to identify the environmental factors that influence the rate of ectotrophic mycelial growth of Phellinus weirii (Murr.) Gilbertson along Douglas-fir roots were undertaken both in the laboratory and in the field. The effects of soil pH, nitrogen, moisture, temperature, microorganisms and bulk density were investigated. In the lab, the...
A modified slide-dip bioassay was used to survey and establish
baseline resistance levels in Psylla pyricola Foerster from
western Oregon orchards to four pesticides. Orchards selected in the
Hood River, Rogue River and Willamette Valleys spanned a wide range of
environmental and management conditions. During the study period of
1982-1983,...
Phellinus weirii (Murr.) Gilbertson, cause of laminated
root and butt rot, is a heterothallic basidiomycete lacking
clamp connections. Two biological species groups of the fungus
have been hypothesized, the Douglas-fir and cedar-types, on the
basis of physiological, morphological and epidemiological
differences. Single-spore and vegetative isolates differ in
cultural morphology, nuclear...
An Internet Map Server (IMS) web site was constructed with the goal of
helping middle- through high-school students learn about ocean processes. This IMS was
developed in conjunction with the activities of the Science & Math Investigative
Learning Experience (SMILE) program, and for eventual use with the Oregon Coastal
Atlas,...
The purpose of this document is to display a portion of the work I have completed over the last two years. The Athlete is the recently written opening to a novel of the same name. I've decided not to excerpt a longer section of the novel because the novel isn't...
New methods, sensors, and devices based on redox indicators were developed to
monitor redox conditions in anoxic and anaerobic laboratory systems and the subsurface
environment. The primary application was monitoring redox conditions
during the dechlorination of tetrachioroethene (PCE) to ethene (ETH) in packed
columns and microcosm bottles containing an enriched...
A field experiment designed to test the hypothesis that infragravity and lower frequency waves influence the patterns of erosion and deposition on the beach foreshore has been carried out. The data show coherent fluctuations in the foreshore sediment level which can be related to low frequency wave motions. The fluctuations...
The amount and quality of competition among
individuals in developing plant communities is an important factor determining community structure, composition and development. In perennial plant communities, this competition is reflected by shifts in carbon allocation among plant parts and can result in long-term structural differences between neighboring individuals. This study...
An Internet Map Server (IMS) web site was constructed with the goal of
helping middle- through high-school students learn about ocean processes. This IMS was
developed in conjunction with the activities of the Science & Math Investigative
Learning Experience (SMILE) program, and for eventual use with the Oregon Coastal
Atlas,...
Coastal flood hazard zones and the design of coastal defenses are often devised using the maximum
recorded water level or a ‘‘design’’ event such as the 100 year return level, usually projected from
observed extremes. Despite technological advances driving more consistent instrumental records of waves
and water levels, the observational...
Balanced nutrition is important for efficient livestock production.
Daily nutrient requirements vary depending on the phase of production. Knowing the nutrient composition of feeds and matching feeds to animal requirements at a given stage of production will ensure that nutritional needs are met. Forage analysis is a management tool that...
Extreme water levels generating flooding in estuarine and coastal environments are often driven by compound events, where many individual processes such as waves, storm surge, streamflow, and tides coincide. Despite this, extreme water levels are typically modeled in isolated open-coast or estuarine environments, potentially mischaracterizing the true risk of flooding...
The wave-induced velocity field in the nearshore is composed of contributions from incident wind waves (f > 0.05 Hz), surface infragravity waves (f < 0.05 Hz, lkl < (σ²/gβ) and shear waves (f < 0.05 Hz, lkl > σ²/gβ), where ƒ is the frequency, σ = 2πf, k is the...
A form of the linear, inviscid shallow water wave equation which includes alongshore uniform, but cross-shore variable, longshore currents and bathymetry is presented. This formulation provides a continuum between gravity waves (either leaky or edge waves) on a longshore current, and the recently discovered shear waves. In this paper we...
Because of highly dissipative conditions and strong alongshore gradients in foreshore
beach morphology, wave run-up data collected along the central Oregon coast during
February 1996 stand in contrast to run-up data currently available in the literature. During
a single data run lasting approximately 90 min, the significant vertical run-up elevation...
Probabilistic flood hazard assessment is a promising methodology for estuarine risk assessment but currently remains limited by prohibitively long simulation times. This study addresses this problem through the development of an emulator, or surrogate model, which replaces the simulator (in this case the coupled ADCIRC+SWAN model) with a statistical representation...
Many habitat selection studies have focused on the importance of spatiotemporal scales and sample size, yet often hidden within is a trade-off between using more animal locations versus more predictive covariates. Few have evaluated the outcome of choosing between these two different paths even though the trade-off can have significant...
Oregon State University operates a World-Wide Standard Seismograph
Station at Corvallis (COR) and a seismic station at Klamath Falls
(KFO), Oregon. Data recorded at the Portland (PTD), Oregon, seismic
station, operated by the Oregon Museum of Science and Industry, are
included in this Seismological Bulletin.
The Corvallis station includes three...
This project was carried out collaboratively by Oregon State University (OSU) and the Oregon Department of Geology and Mineral Industries (DOGAMI) and involved continuation of the beach monitoring program begun in summer 2009 to determine baseline conditions and beach variability at the site of the planned Reedsport wave energy conversion...
Planetary or Rossby waves are the predominant way in which the ocean adjusts on long (year to decade) timescales. The motion of long planetary waves is westward, at speeds ≥1 cm s⁻¹ . Until recently, very few experimental investigations of such waves were possible because of scarce data. The advent...
The authors have used a spectral, primitive equation mechanistic model of the stratosphere and mesosphere
to simulate observed stratospheric flow through the winters of 1991–92 and 1994–95 by forcing the model at
100 hPa with observed geopotential height. The authors assess the model’s performance quantitatively by
comparing the simulations with...
In this report, a response is given to the charge of this study. Volume I: Summary Report includes a synopsis of the technical considerations followed by the main findings and recommendations. The full technical background for these summary statements is given in detail in Volume II: Technical Background Report, and...
Mastitis is the single most expensive disease to the dairy industry, contributing to large financial losses due to decreased quantity and quality of milk. It's essential to develop and implement a mastitis
control program to keep mammary glands healthy and reduce infection in the herd. Removing the hair from a...
During the discovery and description of seven New Zealand methane seep sites, an infaunal assemblage dominated by ampharetid polychaetes was found in association with high seabed methane emission. This ampharetid-bed assemblage had a mean density of 57,000 ± 7800 macrofaunal individuals m⁻² and a maximum wet biomass of 274 g...
Abstract: Significant declines in spring Northern Hemisphere (NH) snow cover extent (SCE) have been observed over the last five decades. As one step toward understanding the causes of this decline, an optimal fingerprinting technique is used to look for consistency in the temporal pattern of spring NH SCE between observations...
Swiss needle cast (SNC), an important fungal disease of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), has increased in severity throughout its natural and introduced range over the last half century. The role of climate change and forest management practices in the increase is unclear. We analyzed tree-ring chronologies from six late-successional...
Coastal communities face heightened risk to coastal flooding and erosion hazards due to sea-level rise, changing storminess patterns, and evolving human development pressures. Incorporating uncertainty associated with both climate change and the range of possible adaptation measures is essential for projecting the evolving exposure to coastal flooding and erosion, as...
This repository item contains the files needed to reproduce the results reported in the published work entitled "Runups of unusual size: rogueness and variability of swash" in the Journal of Geophysical Research. As described in the publication, the results described within it pertain to simulations of wave runup for various...
Marine macrophyte wrack (macroalgae and seagrasses) frequently washes onto beaches but little is known about the factors controlling its biogeographic variability. We report on a large-scale study of macrophyte wrack deposition patterns on the US Pacific Northwest coast. We measured macrophyte wrack on 12 sandy beach sites from southern Washington...
Appearing in this issue of the Journal of Physical Oceanography are three papers that present new observations of a distinct, narrow band, and diurnally varying signal in temperature records obtained in the low Richardson number shear flow above the core of the equatorial undercurrent. Moored data suggest that the intrinsic...
The collapse of the Laurentide Ice Sheet over Hudson Bay ∼8.47 ka allowed the rapid drainage of glacial Lake Agassiz into the Labrador Sea, an event identified as causing a reduction in Atlantic meridional overturning circulation (AMOC) and the 8.2 ka cold event. Atmosphere‐ocean models simulations based on this forcing,...
Changes in soil C and N pools following wildfire are
quite varied, but there is little understanding of the
causes of the variation. We examined how the
legacies of prefire ecosystem structure may explain
the variation in soil trajectories during the first
decade following wildfire. Five years prior to
wildfire...
Changes in soil C and N pools following wildfire are
quite varied, but there is little understanding of the
causes of the variation. We examined how the
legacies of prefire ecosystem structure may explain
the variation in soil trajectories during the first
decade following wildfire. Five years prior to
wildfire...
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Prefire Ecosystem Structure in
Douglas-Fir Forest
Peter S. Homann,1* Bernard T. Bormann,2 Brett A
Nitrosomonas europaea is a chemolithoautotrophic bacterium that oxidizes ammonia (NH₃) to obtain energy for growth on carbon dioxide (CO₂) and can also produce nitrous oxide (N₂O), a greenhouse gas. We interrogated the growth, physiological, and transcriptome responses of N. europaea to conditions of replete (>5.2 mM) and limited inorganic carbon...
Nitrosomonas europaea is a chemolithoautotrophic bacterium that oxidizes ammonia (NH₃) to obtain energy for growth on carbon dioxide (CO₂) and can also produce nitrous oxide (N₂O), a greenhouse gas. We interrogated the growth, physiological, and transcriptome responses of N. europaea to conditions of replete (>5.2 mM) and limited inorganic carbon...
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Giguereb, Frank Chaplenc, Peter J. Bottomleyb,d, Luis A.
Sayavedra-Sotoa#.
aDepartment of Botany and
Nitrosomonas europaea is a chemolithoautotrophic bacterium that oxidizes ammonia (NH₃) to obtain energy for growth on carbon dioxide (CO₂) and can also produce nitrous oxide (N₂O), a greenhouse gas. We interrogated the growth, physiological, and transcriptome responses of N. europaea to conditions of replete (>5.2 mM) and limited inorganic carbon...
Full Text:
Andrew Giguere,b Frank Chaplen,c Peter J. Bottomley,b,d Luis A. Sayavedra-Sotoa
Department of Botany and
In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now...
Full Text:
the reader to a number
of papers for background, including those by Shields [1936], Meyer-Peter and
In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now...
Full Text:
climatic and land use changes: A review of methods and research needs
Forecasting the response of Earth's
Early-successional stages have been truncated and altered in many western U.S. forest landscapes by
planting conifers, controlling competing vegetation, suppressing fire, and focusing on maintaining late-seral
species and undisturbed riparian zones. Declining area of early-successional stages may be reducing
resilience and sustainability on landscapes that experience elevated disturbance related to...
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-Whitman National Forest, 1550 Dewey Ave,
PO Box 907, Baker City, OR 97814
Peter S. Homann3, Dept. of
Early-successional stages have been truncated and altered in many western U.S. forest landscapes by
planting conifers, controlling competing vegetation, suppressing fire, and focusing on maintaining late-seral
species and undisturbed riparian zones. Declining area of early-successional stages may be reducing
resilience and sustainability on landscapes that experience elevated disturbance related to...
Full Text:
,⇑, Robyn L. Darbyshire b, Peter S. Homann c, Brett A. Morrissette d, Susan N. Little e,1
aUSDA Forest
The spatio-temporal overlap of morphologically undistinguishable weak and healthy stocks is a major concern for the Pacific Northwest troll Chinook salmon fishery. Regular fishery closures have led to major financial losses calling for alternative regulatory measures. One approach for such complex and pressing socio-ecological challenges is the transition towards transdisciplinary...