Five simulated precipitation patterns characteristic of the Columbia
Basin and Plateau region and six fertilization rates were evaluated
for their effect on percent crude protein, percent in vitro dry matter
digestibility, fiber content, and yield of wheat aftermath on a commercial
farm in north central Oregon.
The higher moisture regimes...
The shallow water benthic habitat of the SW Beaufort Sea is frequently
gouged by the keels of ice pressure ridges. This natural physical
disturbance was hypothesized to be an important factor affecting the
structure of the benthic community. Smith-McIntyre grab samples were
taken from three discrete gouge axes and from...
Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges groundwater for over 1 billion people globally. Despite its importance to water resources, our understanding of the storage capacity...
Species and cultivar combinations have been relatively well studied, though little is known about the influence of spatial arrangement on agricultural or native plant mixtures. The effect of spatial pattern on mixtures was explored in three experiments. In the first two, agricultural and native plants were planted in two-way mixtures...
Forested, mountain landscapes in the Pacific Northwest (PNW) are changing at an unprecedented rate, largely due to shifts in the regional climate regime. Documented climatic trends across the PNW include increasing wildfire frequency and intensity and an increasingly ephemeral snowpack, especially at moderate elevations. One relationship that has yet to...
The Gorda Escarpment (40.4° N and from 126° W to 124.7° W) is a topographic high which is the eastern portion of the Mendocino Transform Fault. The Vizcaino Block is the anomalously shallow portion of the Pacific plate immediately south of the Gorda Escarpment. Sediments of the Vizcaino Block record...
Arctic-boreal regions are exhibiting the symptoms of profound ecological shifts as they experience pronounced warming. Wildlife in high-latitudes are one such harbinger of change, and their populations are undergoing range-shifts, declines, and extinctions in response to their rapidly altering habitats. As the circumpolar and boreal north is snow-covered for up...
The purpose of this research was to do a comparative study of
the self-concept of Mexican-American/Chicano(a) students enrolled
in two- and four-year institutions of higher education in western
Oregon during the 1985-1986 academic year.
The secondary purposes of the research were:
1) To ascertain if there were any significant differences...
During eleven cruises conducted off the Oregon continental
slope from April 1973 to March 1975, approximately 1600 specimens
of the majid crab Chionoecetes tanneri Rathbun were collected.
A time sequence of size frequency histograms and bivariate plots of
allometric measurements were used to determine size classes,
population structure, growth and...
Eleven cruises were conducted on the Oregon continental slope from April 1973 to March 1975 to assess the biology and ecology of the Tanner crab, Chionoecetes tanneri Rathbun. Bathymetric and seasonal analysis of the distribution of adult Tanner crabs west of Coos Bay, Oregon, revealed no segregation of sexes or...
Passive sampling devices have been used for decades to measure complex mixtures of bioavailable organic chemicals in a variety of environmental media. More recently passive sampler applications have expanded beyond monitoring chemical concentrations, and this dissertation continues to advance methods of passive sampling on many fronts. Despite their growing use,...
During the 2011 Great East Japan Earthquake and Tsunami, numerous bridge structures were damage or destroyed. The damage to bridge systems was caused by long duration strong ground shaking, tsunami inundation forces, or both. Long duration strong ground shaking from subduction zone earthquakes and the multi-hazard scenario of combined earthquake...
Annual rates of prespawn mortality (PSM) in adult Chinook salmon (Oncorhynchus tshawytscha) trapped and transported upstream of dams in the Willamette River basin are high (often >40%) and could limit the ability to restore natural populations of spring Chinook salmon if not reduced. Improvements at the U.S. Army Corps of...
Erwinia amylovora is a plant pathogenic bacterium that causes the destructive disease fire blight of apple and pear. We examined the plasmid content of a collection of 305 isolates of E. amylovora from Washington and Oregon with PCR assays and RFLP. Nearly all isolates of E. amylovora carried plasmid pEA29,...