Water quality and stream flow data for tliree representative land uses in the Tualatin River Basin were evaluated to determine the comparative levels of various pollutants. In addition, the data were used in an effort to identify the extent to which observed concentrations of total and ortho phosphorus could be...
The goal of this phase of the study was to develop a model of the Tualatin River incorporating Scoggins Creek and Hagg Lake. This tool will be used in conjunction with a hydrologic model, the EPA HSPF model (Johnson, Imhoff, and Kittle, 1984), to analyze management strategies to improve water...
The Tualatin River Basin in Washington County, Oregon has been identified by the Oregon Department of Environmental Quality (DEQ) as "Water Quality Limited." Algal blooms have become commonplace in the lower , reaches of. the river during summer months. Phosphorus has been identified as the nutrient upon which to base...
This report summarizes the conclusions reached in "A Project to Collect Scientific Data and Provide Evaluation and Recommendations for Alternative Pollution Control Strategies for the Tualatin River Basin."
This study was funded by the Oregon Department of Environmental Quality as a grant to the Oregon Water Resources Research Institute on...
The Tualatin River Basin along the east side of the Coastal Mountains in Oregon is subject to a complex mixture of land uses. Approximately half the area is devoted to forestry production. The remainder is divided between agriculture and urban uses. In addition to this diversity in land use, there...
This report presents estimates of land uses, concentrating on agricultural land in the Tualatin drainage basin. Acreage in different crop groups and agricultural water use and distribution in the watershed were estimated. The total amounts of nitrogen and phosphate applied to agricultural land and the average loading of nutrients per...
The Tualatin River is a major water resource for Washington County. In its course, the river drains forest lands, farmlands, and urban areas receiving toxic materials from non-point source runoff: Wastewater treatment plant effluents from municipalities and industries also contribute toxic materials to the river. Many materials discharged into the...
In response to Oregon House Bill 3338, the Oregon Department of Environmental Quality requested proposals in 1991 to assemble available information on Tualatin River Basin conditions to provide a scientific basis for improving river water quality. An interdisciplinary team of researchers from Oregon State University and Portland State University was...
The Tualatin River in northwest Oregon has been designated as water quality limited by the Oregon Department of Environmental Quality. Restoration and enhancement of riparian areas to improve water quality is one task to be pursued by management agencies. This paper examines some of the potential costs and benefits of...
About one-third of the land in the Tualatin Basin is used for agricultural production (Miner, Scott, and Wood, 1994). The variety of crops produced includes grains, specialty seeds, vegetables, fruits, berries, and nursery corps. Cattle and hog enterprises are the most prevalent livestock operations in the area (measured by number...
Dionysius said that history is philosophy learned from examples. As one of the original four counties of the Territory of Oregon, the Tualatin River Basin is rich in history. While still a prime agricultural region, the Tualatin Valley is one of the state's fastest developing areas. The slow accumulation of...
The Tualatin Basin landscape has undergone extensive change since the initiation of Euro-American settlement, with important consequences for basin hydrology and water quality. Changes that include the isolation of the Tualatin River from its floodplain areas, losses of important wetlands and riparian areas, and urbanization associated with population growth in...
Experiments were conducted to determine the influence of cultural management practices on weed growth in nursery containers. Experiments 1 and 2 evaluated the effects of dolomitic lime rate and application method on substrate pH, creeping woodsorrel (Oxalis corniculata L.) establishment in containers, and growth of azalea (Rhododendron ‘Rosebud’) and pieris...
The purpose of this study was to explore the phenomenon of community colleges creating pathways to degree completion in professional-technical programs by breaking degree programs into smaller portions, referred to as "chunks." The purpose or possible advantage of chunking was that it would improve the rate of degree completion among...
Continuously tunable diode laser sources coupled to single-mode fiber are useful sources for fiber Bragg grating (FBG) strain sensors. This paper describes the
development and fabrication of such a device. An introduction is given describing
applications of tunable lasers and some of the different methods of creating a tunable
diode...
Four aspects of factors influencing the accuracy of nondestructive chlorophyll (Chl) and nitrogen (N) measurement in fresh leaves were studied: (1) optimum wavelength (OW) identification; (2) indices development and evaluation; (3) influence of leaf properties; and (4) influence of meter parameters and sampling technique. Results were used to develop indices...
Fire is a major disturbance process in many forests. Long-term studies of the biogeochemical effects of fires, especially on soils, are very rare.
Consequently, long-term effects of fire on soils are often hypothesized from
short-term effects. In a chronosequence study, I studied 24 western Cascades
(Oregon) forest stands thought to...
As part of the Willamette Basin Geographic Initiative Program, the Environmental Protection Agency (EPA) funded The Nature Conservancy of Oregon to inventory, classify, and map native wetland and riparian plant communities and their threatened biota in the Willamette Valley. Between October 1994 and September 1996, we evaluated 172 wetland and...
This research was designed to broaden the understanding of how timber-harvest affects aquatic macroinvertebrates in perennial and intermittent headwater streams. This study compared emergent and benthic macroinvertebrate assemblages from 20 headwater streams in the central Oregon Coast Range that varied by harvest condition and flow duration. Through comparison of the...
The purpose of this project was to investigate play and our cultural assumptions as to its usefulness or lack there of. The concepts of hard work versus hard play were explored in order to discover when human beings are operating at their best. In terms of innovation and productivity in...
The Elliptic Curve Digital Signature Algorithm (ECDSA) is a public key cryptosystem used for creation and verification of digital signatures in electronic documents. In this thesis, we created a Java applet that provides the functionality of the ECDSA using all of the NIST elliptic curves over GF(p). This applet was...
Tot Mizaj, a central term in Traditional Uyghur Medicine (TUM) theory, says there are four typical characters in all things in nature; the geography, people, organs, animals, foods, and medicines. It is by maintaining balance of these characters that existence is perpetuated. Each Mizaj, corresponding to one element; fire, air,...
Hispanics in Hood River County, Oregon account for roughly 25% of the population, with many employed in agriculture. A community health survey was carried out in Hood River County during the winter months of 2001 with the purpose of evaluating the health conditions, needs, and barriers to access of needed...
Community colleges are experiencing a decline in state allocated funding. Traditionally, college administrators look for ways to cut expenditures and raise tuition and fees to make up for the shortfall. Using available land resources to generate a revenue stream may provide revenue for community colleges.
The purpose of this study...
Designing spectral efficient, high-speed wireless links that offer high quality-
of-service and range capability has been a critical research and engineering challenge. In this thesis, we mainly address the complexity and performance issues of
channel estimation and data detection in multiple-input multiple-output (MIMO)
orthogonal frequency division multiplexing (OFDM) systems over...
Although the question of free will has persisted throughout the history of philosophy as an important metaphysical consideration, rarely does the inquiry include empirical evidence from other disciplines concerned with human behavior. In this interdisciplinary paper, I combine the wisdom of psychologists, metaphysicians, and philosophers of science to comment on...