Chromium and its compounds are widely used by modern industries, resulting in large quantities of this element being discharged into the environment. To remove chromium from contaminated soils and ground water, it is necessary to predict chemical and physical processes that control the rate of reactions and transport of chromium...
This research analyzes the effects of islands on river process and the effects river processes have on island formation. A fluvial island is defined herein as a land mass within a river channel that is separated from the floodplain by water on all sides, exhibits some stability, and remains exposed...
The mechanisms of pool maintenance were investigated in a small (width = 10 m,
drainage area = 18 km2), gravel-bed stream where pools are commonly associated with
large, in-channel obstructions. Measurements of boundary shear stress, scour and fill of
the stream bed, and bedload transport rate and grain-size distribution were...
Waves are the primary input of energy in the nearshore region, and together with the currents forced through the transfer of momentum that occurs during the wave breaking process they are the principal mechanism for sediment transport in the nearshore. The basic physics of waves and currents are thought to...
The 14-km long Netarts Littoral Cell, located on the northern Oregon coast, experienced episodic erosion as a result of the severe 1997-98 El Nino and 1998-99 La Nina. The erosion events led to the development of a unique partnership bridging scientists, stakeholders, and various planning agencies. To address these erosion...
The longshore variability of the coastal response to hurricanes may be examined within the framework of a storm-impact scaling model that compares spatially-variable beach morphology and fluid forcing. The relative elevations of dune height and storm-induced water levels are used to define three impact regimes (swash, collision, and overwash), within...
Forest managers in the Blue Mountains, of northeastern Oregon are currently faced with
vast areas of forests with health problems and high fuel loadings. These conditions
resulted from a combination of insect infestations, past management practices and the
elimination of fire from the local ecosystems. These forests are now overstocked,...
Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture,...
Rubus spp. seeds have a thick protective endocarp and testa (seedcoat) that can
restrict germination even under favorable conditions. The effect of pregermination
treatments were studied in Rubus chamaemorus L., R. eustephanos Focke ex Diels, R.
idaeus 'Amber' L., R. leucodermis Douglas ex Torrey & A. Gray, R. multibracteatus A....
Climate change remains controversial and misunderstood, despite the consensus among climate scientists that recent climate change is anthropogenic. Many American adults do not agree with or do not understand this scientific consensus, suggesting a disconnect in science communication or a distrust in science. This disconnect may begin in formal education...
Italian ryegrass [Lolium perenne L. ssp. multiflorum (Lam.) Husnot] resistant to multiple herbicide sites of action continues to limit winter wheat production in western Oregon. In addition to impacting wheat production, multiple resistant Italian ryegrass may threaten the market for annual ryegrass seed for cover crops if wheat fields with...
Photonic sintering of nanoparticles is a relatively new process for sintering of nanoparticles, deposited on a substrate, into functional solid structures. The working principle of this process is the incidence of large-area broad-spectrum light onto deposited nanoparticles, which results in heat generation in the nanoparticles and their subsequent densification. Key...
Vertically shoot positioned (VSP) training systems are common in Oregon's Willamette Valley, where deep fertile soils and high regional precipitation task growers with curbing vegetative vigor within this system. Management strategies, such as canopy hedging and cluster-zone leaf removal, are used to improve microclimate within the canopy and around the...
A study of the phyletic relationships among five species of
tragopans and an outgroup, the Blood Pheasant (Ithaginis cruentus), was
conducted from 1987 to 1991. Biochemical, behavioral, and external
morphologic characteristics were compared. A cladistic approach was
used to compare the behavioral, biochemical, and external morphologic
data collectively, as different...
Northeastern Oregon geology and climate provides moderately productive conditions for forest management and timber production. Although site preparation and planting are commonly used silvicultural practices, little research exists on the efficacy of specific forest herbicides and responses of seedling survival and growth in this region. This research seeks to improve...
The scale of pest and disease dispersal is often larger than the scale of individual farms. Therefore, an individual grower’s response to pests and diseases can affect and is affected by their surrounding growing region. Individual growers are also not isolated, and engage in various forms of information gathering, sharing,...
This dissertation investigated potential ecological limitations to seedling regeneration in young, seasonally dry, evergreen forest restoration plantations in northern Thailand. We explored whether recruitment of colonizing tree species in the restoration plantations can be attributed to seed dispersal mode (i.e. abiotic or animal dispersal) and seed size. We did this...
A microfluidic nanofiltration module has been designed, fabricated and applied to the continuous-flow, pressure-driven, post-synthetic purification of macromolecules and nanoparticles via diafiltration using a commercially available organic solvent resistant nanofiltration membrane, STARMEM 122. This module will readily interface with other microscale components within a
"nanofactory" for the rapid synthesis, purification...
This research addresses sample process variance estimation on continuous domains and for non-probability samples in particular. The motivation for the research is a scenario in which a program has collected non-probability samples for which there is interest in characterizing how much an extrapolation to the domain would vary given similarly...