Seed size, abundance, viability, dormancy, and germination requirements strongly influence plant establishment and therefore are important considerations in restoration of native vegetation. These characteristics provide criteria for selection of suitable species, development of collection and pretreatment methods, and determination of seeding densities. The first set of objectives of this study...
An analysis of variational data assimilation schemes for linear dynamical forecast models shows that the penalty functional must include an explicit contribution from the initial conditions in order to ensure a unique, low-noise forecast. The noise level is related to the effective number of data being assimilated.
The purpose of this study was to determine the effects of long-term weighted vest
exercise on hip bone mass, functional ability and static balance in elderly women. This was
a within subject exercise intervention study and included a 6-month control period.
Twenty-three subjects (age 85 ± 6) were recruited and...
Three experiments whose objectives were to investigate cover
crop kill by winter freeze, weed suppression by 'Micah' barley and
other spring cereals, and allelopathic potential of cereal covers
were conducted at the Vegetable Research Farm and in the greenhouse
and growth chamber facilities at OSU in 1989/90. Kill by winter...
Published April 1991. Reprinted June 1993. 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
Examines the problems of runoff and nonpoint source pollution in Oregon's Tualatin River and how local residents and government officials are trying to reduce nonpoint source pollution. It also offers tips to help each of us play an active role in cleaning up our nation's drinking water supplies.
The goal of this research project is to determine the fractal nature, if any, which
surface water waves exhibit when viewed on a microscopic scale. Due to the
relatively recent development of this area of mathematics, a brief introduction to the
study of fractal geometry, as well as several examples...
Alongshore-separated time series of natural swash motions were obtained over a range of environmental conditions using a video technique. Although the frequency spectra and normalized wavenumber spectra for these motions were particularly bland, wavenumber-frequency spectra of these data showed clear partitions of infragravity band energy levels associated with various wave...
The purpose of this thesis is to apply the wavelet transform WT to
multiresolution structures for analyzing the information content of images based on
multiresolution signal decomposition of the wavelet representation. The advantage
of the wavelet transform is the fact that it uses different building blocks than the
Fourier's sines...
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...
Two types of boundary element models are developed for the interaction of waves with trenches. The first type is for a two-dimensional domain in the horizontal plane and employs the linear long wave approximations. It is shown that appropriate selection of pit geometries leads to a significant reduction in wave...
Knowledge about vegetation patterns and ecological processes in unmanaged, late-successional
watersheds is needed to provide a foundation for forest management strategies
aimed at conserving native biodiversity. I examined influences of environmental variability
and disturbance history on forest structure and composition in the Cummins Creek
Wilderness, located on the central Oregon...
Most recent research on stream amphibians in the Pacific Northwest has focused on associations with reach-level or stand-level environmental features. Little is known about landscape-level distributions of these species or landscape-level aspects of their life-histories. I used a watershed-wide sample and logistic regression to develop models and maps of probability...
There are many parallels between the 1978 legislation to expand Redwood National Park and the Northwest Forest Plan, which together with the Northwest Economic Adjustment Initiative formed the 1993 Pacific Northwest Initiative. In both situations, the Federal Government sought to promote retraining for displaced workers, to undertake watershed assessment and...
Studies are currently underway to determine the suitability of Yucca Mountain
in Nevada as the nation's first high-level nuclear waste repository. Values of net
infiltration are required to determine pre-waste emplacement groundwater travel times
and the performance of the repository as a waste containment system. The objective of
this study...
Published March 1991. 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
Revised August 1997. 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
Oregon's watershed councils are local, non-regulatory, collaborative forums charged
with the recovery of endangered salmon and improving water quality under The Oregon Plan for Salmon and Watersheds. Private forest landowners, given their prominence is owning riparian areas, are central to success of these efforts. Using a statewide survey of watershed...
This supplement to Waterfront Revitalization For Small Cities, EM 8414, is a companion reference for planners, community officials, and citizens in Oregon waterfront communities. Its three parts are designed to answer the question, "Where do we go for help here in Oregon?" Sources of technical and financial information and assistance...
Published March 1990. 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
This article is based on a total of 353 observations, many of which were systematic censuses.
At West Beaver Pond, Llewellyn made 225 observations of waterbirds during 1982-June 1993. He noted a total of 19 taxa; 53% were seen in five or more of the 10 years with many observations....
In 1984-1986, Bayer made 171 and 67 waterbird censuses at West Pond and East Pond, respectively. From 1974 through June 1992, Bayer and others also made an additional 138 and 110 observations at West Pond and East Pond, respectively. A total of 48 waterbird taxa were reported at West Pond,...
This article is based on a total of 204 observations, many of which were censuses.
Between Siletz River Mile (RM) 50.0 and 50.6, Llewellyn made 151 observations of waterbirds during 1981-1993. He noted a total of 12 species; most were seen during several years. Hooded and Common mergansers and American...
The applicability of anhydrous milkfat fractions in edible films and coatings was determined through moisture barrier, penetrometer, and stress-relaxation testing. Industrial milkfat fractions were compared along with tripalmitin:anhydrous milkfat blends which simulated milkfat fractions having different melting points. The water vapor permeability (WVP) was determined gravimetrically using a modified ASTM...
Excised stem segments of vines had higher specific hydraulic conductivies (flow rate per pressure gradient per stem transverse area) than did trees during the dry season in a deciduous forest in Jalisco, Mexico. Vine species averaged from 2.7 to 203 x 10-3 m2 MPa-1 s-1 and tree species from 0.8...
Stephens winter wheat was grown using conventional furrow irrigation and surge irrigation on 12 one-half-acre plots. Both systems were operated simultaneously four times during the season. Conventional irrigation applied 26.5 ac-in/ac of water with runoff of 0.8 ac-in/ac and infiltration of 25.7 ac-in/ac. Surge irrigation applied 13.7 ac-in/ac with 0.5...
The overall objective of the study is to measure changes in agricultural production and water use patterns under various water supply and allocation mechanisms. The methodology nests an economic model of on-farm decisions in a basin-wide hydrologic model. The economic model forecasts the use of applied water, technology and crop...
Sorbitol-induced osmotic stress (SIOS) to the root was found to be effective in
reducing transpirational water loss in plants during water stress. Mechanisms of SIOS in
stomatal control were investigated in containerized apples (Malus domestica Borkh.
'Gala'/M26) when leaf water potential (Ψw), osmotic potential (Ψs), turgor potential (Ψp),
stomatal conductance...
The goal of this thesis was to determine the physiological mechanisms that link adverse preplanting treatments of Douglas-fir, such as exposure and root pruning, to the phenomenon of transplanting shock. The objective of experiments 1 and 2 was to measure the effect of exposure and pruning on the physiology and...
Both red (Trifolium pratense L.) and white (Trifolium repens L.) clover
seed yields can be highly variable and low in western Oregon. The objectives of
this study were to: i) determine crop water requirements and supplemental
irrigation timing, and ii) quantify the effects of soil and water status on
inflorescence...
Water quality problems related to excessive algal
growth, high nutrient loading, and low flows have been
occurring along Oregon's Tualatin River. The Tualatin River
is 86 miles long and has a drainage basin of 711 square
miles. The drainage basin incorporates forest,
agricultural, and urban areas. Located in the Portland...
Dormancy of 'Pinot Noir' grapevines was characterized. Primary buds
required ca 300 cumulative chilling hours (CCH) to initiate the transition from
endodormancy to ecodormancy, which occurred in mid November. Additional
chilling, up to 1000 CCH, improved budbreak. Changes in bud water content
were estimated by gravimetric and spectroscopic methods. Total,...
Observations during the Coastal Transition Zone (CTZ) experiment in summer 1988 reveal the
presence of deep phytoplankton layers in a coastal upwelling system. The layers occur throughout the
CTZ study area, including a strong baroclinic jet which was present over the period of the experiment.
On the basis of a...
There is no information available on water management of birdsfoot
trefoil grown for seed. Information is also not available describing how to
minimize seed losses due to shattering in order to obtain consistently high
birdsfoot trefoil seed yields. The objectives of this research are to: (i) quantify
crop water use,...
Population size of Clavibacter michiganensis subsp.
sepedonicus in potato cv Russet Burbank and plant response
as affected by drought were assessed in a greenhouse
experiment. Water deficit stress and no stress treatments,
and inoculum densities of 0 or 2 X 10⁷ cfu C. m.
sepedonicus/seed piece were arranged factorially. Stem...
Sandy soils are among the least productive soils because of their inability to
store adequate water for plant growth. Their high percolation rate not only allows
water to move quickly beyond the root zone, but also washes nutrients below the reach
of plant roots. High evaporation occurs from the soil...
Published September 1994. 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