Soil moisture in a crop's root zone must be regularly
monitored to accurately predict crop water requirements.
Most irrigation scheduling services currently
use the neutron probe to monitor soil moisture. Unfortunately,
there is a degree of variability associated
with use of the neutron probe creating uncertainty in
measurements of soil...
Improved water use efficiencies in irrigated agriculture are necessary to assist in coping with the accelerating demand and economic competition for the world's fresh water supply and increasing ecological concerns. This will likely rely in part on optimum irrigation, which implies regulated deficit irrigation. While conventional irrigation management is intended...
Potato ground cover and spectral data were measured
in the Columbia Basin during the 1990 growing season.
Three spectral were correlated with ground cover;
normalized difference, near infrared-red ratio, and the
first derivative of the spectral curve at 750 nm. All
models were statistically significant at the 99% level.
Normalized...
This study investigated the effect of plant surface
area (plant density) on the efficiency of organic carbon
removal in a bench-scale constructed wetland.
Constructed wetlands are commonly assumed to be biofilm
reactors in which organic carbon removal occurs primarily
through sedimentation and aerobic degradation by attached
microbial biofilms. In conventional...
Recycling of water in aquaculture facilities is used to minimize the amount of energy or tempered water required to control water temperatures. The rate of heat exchange between the water and the environment can be an important variable in the design, management, and economic analysis of a recycle system. A...
Nitrate contamination in ground and surface waters is of great concern to environmentalists. A two-dimensional model of water and solute movement in soils was used to test the usefulness and relative advantages of a two-dimensional model over a one dimensional model for analysis of deep percolation and nitrate leaching in...
Deliberately underirrigating a crop may yield economic
benefits. The optimal use of water by an irrigator
should be achieved under a deficit irrigation regime. It
is important to know how water deficits affect yields and
the interaction of the deficits with the scheduling of
irrigations.
A field experiment was conducted...
Under today's environmental conditions and with the increasing worldwide competition for water, errors in irrigation management decisions can be costly. Therefore, providing both accurate evapotranspiration estimation on a daily basis and estimation of the magnitude of error associated with this estimate is vital for informed water management decisions that allow...
The shallow aquifer in Northeast Malheur County, Oregon is polluted with Nitrates at concentrations exceeding federal drinking water standards. Efforts to solve the groundwater problems in this area have focused on developing farm management practices that will increase groundwater quality while maintaining agricultural production. Furrow irrigation is the dominant practice...
This study was prompted by the need for improving the efficiency of irrigation systems at the Oregon South coastal areas. Accurate information about evapotranspiration (ET) rates is essential for maximizing the efficiency of irrigation systems. Currently, ET estimates provided by Bureau of Reclamation AgriMet Program are derived from the Kimberly...
Furrow irrigation is the dominant practice for irrigating row crops in the western Treasure Valley region near Ontario, Oregon. Though improvements have been made in management practices over the years, excessive runoff and deep percolation are still important problems contributing to surface water and groundwater degradation. Field observations were made...
The intermittent or cyclic application of water to
furrows or borders, a method known as "surge flow irrigation",
can significantly improve the advance characteristics
of surface irrigation. Numerous field studies have
shown that the advance of furrows is considerably more
rapid when irrigated by surge flow than by the conventional,...
A growth model is developed for coho salmon which accounts for
temperatures and feeding rates typically encountered in fish hatchery
operation. Feeding rates utilized by the model ranged from
maintenance to maximum utilizable rations. The model is derived from
an empirical equation for maximum growth rate, and a theoretical
equation...
The rainfall regime of the Cape Verde Islands is influenced
by the Intertropical Convergence Zone (ITCZ) resulting in strong
seasonal trends and frequent thunderstorm events. These
events are frequently responsible for the destruction of riverine
structures and valuable crop land.
A menu driven database program (RIS) was developed for
the...
Often furrow irrigation application efficiencies are low compared to sprinkler systems. The primary goal of furrow irrigation is to infiltrate a relatively uniform target depth of water necessary for the crop, while minimizing the amount of runoff. The concept is difficult because water can infiltrate differently at all locations in...
Estimations of plant water use can provide great assistance to growers, irrigators,
engineers and water resource planners. This is especially true concerning the introduction
of a new crop into irrigated agriculture. Growing hybrid poplar trees for wood chip stock
and veneer production under agronomic practices is currently being explored as...
Four years of daily weather observations from Central Tunisia were available for testing the application of the Penman Equation to estimate reference evapotranspiration in the arid climate of Central Tunisia. The data included minimum and maximum temperature, minimum and maximum relative humidity, 24-hour wind run, and lysimeter measurements of reference...
Achieving and maintaining sustainability in irrigated agriculture production in the era of rapidly increasing stress on our natural resources require, among other essential actions, optimum control and management of the applied water. Thus, a significant upgrade of the currently available soil water monitoring technologies is needed. The primary goal of...
Many regions in North America are experiencing water shortages, and these conditions are expected to worsen. The next generation of irrigation scheduling applications must therefore be capable of providing operational advice in support of deficit irrigation strategies. However, the theoretical, technical, and practical challenges associated with deficit irrigation scheduling are...
Soil water content and water potential are two important parameters in
determining the status of water in the soil. Improvement in the ability to measure these
parameters by way of increased speed, accuracy, resolution, imaging volume, ease of
automation, as well as reduced calibration requirements and reduced soil disturbance
would...
Groundwater contamination on irrigated land is of concern in this nation
and around the world. In order to reduce the potential of groundwater
contamination by agricultural practices such as irrigation, fertilizer and pesticide
application, vadose-zone monitoring and sampling are needed. The main
objective of this study was to evaluate impacts...
Competition for water both from within the irrigation community and from
outside interests has been a major source of conflict in the West. In the Umatilla Basin of
central Oregon, Umatilla River water is diverted to irrigate a variety of crops, while
instream flows have value in salmonid production. Historically,...
Surface water in the Deschutes Basin of central Oregon has been largely over
allocated since the early 1900s. Therefore, rapid population growth and urban
demand for water in the upper Basin lead to an increased reliance on groundwater in
the last three decades. The Oregon Department of Water Resources (OWRD)...
The Washington State Department of Natural Resources' Comprehensive Tree-Volume Tarif Tables are a set of preconstructed local volume tables. This can increase "on plot" efficiency since only diameters are necessary to obtain volumes after the proper table for the given diameter/height relationship is accessed. The tables are accessed and indexed...
Efficient use of water in agricultural production involves accurate assessment
and control of the quantity and spatial uniformity of excess percolation. Passive
Capillary Samplers (PCAPS), which sample water from the vadose zone have shown
potential to provide superior estimates of soil water flux compared to alternative
methods. In a four-year...
Asynthesis & Act is a significant intervention into the discourse of the sublime. Through a deep investigation of the critical metaphysics of Immanuel Kant, the first chapter of this thesis puts forth the claim that the sublime is a radical experience that occasions a possibility for the individual to commit...
Here presented is a photographic catalogue, a key, and literature review for the 35 genera and 90 species of lepturine longhorn beetles (Cerambycidae: Lepturinae) found in the Pacific Northwest. Several nomenclatural changes, recognized by the global taxonomic community, but previously unknown to North American authors, are adopted, and one new...
The rapid development of computing technologies in recent decades has allowed for data to be generated at unprecedented rates. As a result, users are challenged with the task of finding the precise information that they are looking for. Visualization techniques provide the ability to view and analyze data in different...
The agricultural production of peppermint has been shown to contribute significant quantities of nitrate-nitrogen to groundwater recharge. In an effort to provide new tools for increasing nitrogen efficiency within peppermint production, three research questions were proposed: i) How should plant tissue samples be collected to achieve the greatest precision when...
The contamination of ground water resources represents a serious
problem and a prominent threat to the health of our society. This study
focuses on the leaching of inorganic anions as a function of agricultural
practices under natural field conditions. In order to enhance the
understanding of such leaching processes, this...
The need to replace the present methods of rating the acceptability of a manufacturer's lot of strawberries is indicated. Work has been done towards adapting and developing laboratory techniques for this purpose.
The quality factors checked upon were the state of maturity, the effectiveness of processing work, and the freedom...
A wilderness area, as administered by the U. S. Forest Service, is a tract of undeveloped land over 100,000 acres in size with no roads or provision for motorized transportation. Commercial timber cutting, hotels, stores, and similar developments are prohibited. While there are some exceptions for private holdings and administrative...
Published August 1996. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Recent advances in computer technology have made possible the development of expert systems. Expert systems are computer programs that perform at the level of a human expert. Expert systems can help integrate and apply diverse sources of information and expertise to problems of integrated crop management. A prototype Crop Management...
Optimization programming techniques were applied to
develop the least cost formulations for Pacific whiting
surimi-based seafood (PWSBS). To develop the quality
constraint functions, texture and color of whiting surimi
gels were determined by torsion test and colorimeter,
respectively. Whiting surimi gels were produced by heating
at 90°C for 15 min....
Soil solution samplers have certain inadequacies that limit their range of
possible applications. Passive Capillary Samplers (PCAPS), which apply suction to the
soil pore-water via a fiber glass wick, have shown promising results in preliminary
experiments in regard to collection efficiency of water and of bromide tracers. The
objectives of...
A laboratory study of anaerobically digested sewage
sludge was performed to measure equilibrium constants for
ammonia in the sludge. Measured constants describing the
solution and dissociation of ammonia in sludge were compared
to theoretical constants obtained from thermodynamic data.
No significant difference was found between these two sets
of constants....
A hydraulic power-take-off was designed and built for outboard
engines typical of those used on small boats and Pacific City-type
dories. An associated hydraulic system was developed for use on
these boats to provide power for fishing machinery. The power for
each system was provided by a hydraulic pump direct-drive...
This study explored how selected input and redistribution processes affect the amount and arrangement of in-stream wood within the 64 km2 Lookout Creek watershed in the Andrews Forest, western Cascade Range, Oregon. A longitudinal inventory of in-stream wood was conducted over approximately 20 km of stream length in 2nd to...
The research effort described in this report explores the whole question of optimization of irrigation system design, planning and operations. Optimum irrigation practices, in theory, may involve some degree of deficit irrigation (deliberate under-irrigation of crops), hence the focus of this research was the use of deficit irrigation under practical...
In this thesis, I examine the experiences of breastfeeding mothers who chose to give birth with Certified Professional Midwives at a free-standing birth center, and the factors that influence their known high rates of breastfeeding initiation and duration. Using grounded theory and data collected from participant observation, semi-structured interviews, and...
Measurements on growth traits up to 41 years of age
from 68 progeny sites in eight first-generation breeding
zones of coastal Douglas-fir (Pseudotsuga menziesii
[MIRB.] FRANCO var. menziesii) in the US Pacific Northwest
were used to investigate age trends of genetic parameters
and to determine optimum age of selection. Heritabilities...
Tile drainage increases aeration in the root zone of poorly drained soils by
accelerating water movement from the subsurface. Water movement is the main agent
of chemical transport, either transporting soluble materials directly (e.g., nitrate) or by
transporting the soil particles that bind adsorptive compounds (e.g., pesticides). The
detection frequency...
Hydrologic processes within mineral flat wetlands, along with their
connections to groundwater and downstream surface water in lowland agricultural
catchments are poorly understood, particularly under different land uses. In the three
field studies included in this thesis, we examined infiltration, wetland hydroperiod,
groundwater recharge dynamics, surface runoff generation, and water...
While water scarcity and energy demand are continuously increasing in the world, alternative sources are needed to meet the requirement of a growing population. Microbial Fuel Cell (MFC) is a sustainable technology that converts organic matter in wastewater into electricity, thus it can be a potential alternative source for water...
Alternative futures studies provide a way for policy-makers and stakeholders to investigate the future impacts of different management strategies by providing representations of possible outcomes. An alternative futures study was undertaken by the Pacific Northwest-Ecosystem Research Consortium for the Willamette River Basin, Oregon, USA, to determine how this regional system...
Decision-making in environmental management is complex due to the multiplicity arid diversity of management objectives and technological choices. This suggests that modelers and experts could utilize (I) multiple-criteria decision-making (MCDM) approaches to assist stakeholder groups in integrating and synthesizing relevant data and information to address ecological and socio-economic concerns and...
Three related topics have been explored in this thesis. Those three topics deal
with the pricing problems both in the market for access rights to fish and in the market
for seafood. The purpose of this study is to contribute some insights into the global
picture of fishery management and...
Five unique but related studies were conducted at the Oregon State University Dairy
Wetland Treatment System (OSUDWTS), Corvallis, OR. The research site consisted of
six parallel wetland cells, which were built in 1992 and began receiving concentrated dairy
wastewater in the fall of 1993. Hydrologic, hydraulic, and water quality data...
This investigation attempts to demonstrate that the development
of the early 20th century biological enterprise involved a striving for a
unifying theoretical perspective. A skeletal substantiation of this is
given by an overview of early 20th century biology in which some
biologists began recognizing a multiplicity of different orders of...
My thesis is comprised of two articles, titled "Journeying Through (An)Other World: Examining the Role of Magic and Transformational Otherness in Sir Gawain and the Green Knight" and "Magic, Muggles, and Mudbloods: Examining Magical Otherness in J.K. Rowling's Harry Potter Series." The introduction frames the thematic, theoretical, and critical connections...
Over 150 years ago, C. Bergmann observed a within-species pattern of increasing body size as elevation and latitude increased. Bergmann’s data came from numerous endothermic taxa, but the pattern has since been documented among numerous poikilotherms and invertebrates. The ferocious waterbug Abedus herberti Hidalgo (Hemiptera: Belostomatidae) lives in isolated populations...
Electromagnetic engines, or motors, are machines in which the motive power is derived from electric currents by means of their electromagnetic action. The following design is for a 1½ K.W. bi-polar motor.
A new experimental apparatus was built at Oregon State University to perform high resolution stimulated Raman spectroscopy in a pulsed molecular jet at state densities of the order of 10¹¹ cm⁻³. The technique uses a stimulated Raman step to first populate a vibrational/rotational level and then a resonantly enhanced multiphoton...
A study was designed to examine the pharmacokinetics of theophylline in a well defined group of congestive heart failure (CHF) patients, without liver disease, and to evaluate the validity of the dosage guidelines recommended by the FDA. A total of five CHF patients and seven non-CHF patients were entered and...
The immune toxicity of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been studied for over 35 years, but only recently has the profound immune suppression associated with TCDD exposure been linked to induction of regulatory T cells (Tregs). The effects of TCDD are mediated through binding the aryl hydrocarbon receptor (AhR), a ligand-activated transcription...
The incidence and duration of breast feeding were determined
via telephone questionnaires from a sample of 95 women who delivered
healthy infants during the month of September 1982, in the greater
metropolitan area of Portland, Oregon. This sample was limited in
that the women were married, predominately white, over 25...
Electrical resistivity and thermoelectric power measurements
have been made over the temperature range of 450° to 600°C on
n-type liquid thalliurn-tellurium solutions. Liquids with compositions
from 61.5 to 72.0 atomic percent thallium were studied. In addition,
alloys of some of the three component thallium-teIlurium solutions
containing small amounts of silver,...
The purpose of this study was to examine and compare the effectiveness
of two approaches in nutrition education instruction among culturally
diverse adolescents: the teacher-oriented lecture approach and the
student-oriented instructional design approach. The study was
designed to help culturally diverse students gain a basic
understanding of practices that promote...
Two essays are focused on crop choice and the growth of corn production in
the Corn Belt and surrounding areas. The first essay develops a partially
degenerate nested logit model to examine the effect of price islands and local
ethanol capacity on corn production and crop mix. The primary data...
Sustainable elk (Cervus canadensis) habitat management on U.S. Forest Service (USFS) lands involves a complex relationship between management practices and ecological processes. A relatively novel Rocky Mountain elk population (Cervus canadensis nelsoni) on the Plumas National Forest (PNF) in northeastern California became established in the early 2000s, but there is...
Several environmental and cultural factors were studied to
explain the distribution of western juniper (Juniperus occidentalis Hook.)
in an area one mile northwest of Millican, Oregon. In the study area juniper
grows densely on upper south slopes and only sparsely occurs on upper
north slopes. Juniper moisture stress was found...
Globally the forest harvesting industry is becoming increasingly mechanized. Driving this trend is the desire to increase productivity and reduce cost, as well as to improve labor-related issues. With mechanization comes an in-forest platform for the introduction of state-of-the-art communication and measurement technologies, and powerful on-board computers. These systems have...
In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and...
Lincoln City, Oregon is an area of active environmental
processes and increasing development. To reduce conflict, a larger
data base on environmental hazards was required. Previous studies
in the area, remote sensing techniques and. field research were used
to accomplish this end. Within Lincoln City, numerous environmental
hazards were identified...
The addition of macromolecules to solvent, even in dilute quantities, can significantly alter a fluid's response in an extensional, or stretching, flow. When high-molecular-weight polymers are extended in solution, extensional thickening can result, yielding viscosities that are orders of magnitude larger than values found in shear. Examples of applications where...
The goal of this thesis is to identify the factors which have most significantly contributed to historical dam removals in the United States. The trend of increased dam removals over time is specifically analyzed for evidence that increased scarcity of environmental goods and services is motivating dam removals. A theoretical...
The mechanism of continuously chlorinated silver-silver
chloride electrode performance was studied by using a wiped, rotating,
partially submerged, cylindrical silver cathode. The cell
performance using a zinc anode was measured, and the rate of
chlorination of silver was calculated for several water saturated
chlorine atmospheres.
At 75°F, with a chlorine...
E-commerce is growing each year, reaching 130.1 billion in 2008 (Internetretailer.com, 2009b). Retailers have turned their attention to the online channel to discover ways to stay competitive. Yet there is still limited research on online apparel retailing, especially in online product presentation. Thus, the purpose of this study was to...
The diffusion coefficients of several chlorinated hydrocarbons
in air were determined by using an Arnold cell. The chlorinated
hydrocarbons used were carbon tetrachloride, chloroform, 1, 2-
dichloroethane and dichloromethane. To determine the reliability
of the experimental method, diffusion coefficients were obtained
for benzene and ethanol. These were compared with diffusion...
Due to increasing populations, food production must increase significantly to be sustainable. The Internet of Things has been shown to have potential in the field of agriculture to make farming practices more efficient. However, for IoT to be properly integrated into agriculture, sensors must be applied within the field and...
Agricultural education at the high school level, like all vocational programs, is expanding vertically as well as horizontally. With this increased emphasis placed on vocational agriculture, the shortage of teachers is already being felt and the situation will, in all probability, become more critical.
The expansion of the programs to...
We model the popular board game of Clue as an MDP and evaluate Monte-Carlo policy rollout in a simulated environment pitting different agents and policies against each other. We describe the choices we made in the representation, along with some of the problems we encountered along the way. We find...
A complete solution, exact to second-order, for wave motion
forced by a hinged-wavemaker of variable-draft is presented. A
solution for a piston type wavemaker is also obtained as a special
case of a hinged-wavemaker with negative infinite draft. The
existing Stokes inviscid theories for mass transport is extended to
include...