A special apparatus was developed in which the soil moisture
levels of several soil cells could be maintained independently by
various osmotic solutions at a selected temperature. The effect of
four soil moisture suctions and four soil temperatures on the rates
of transpiration, photosynthesis and respiration of monterey pine
seedlings...
A sequence of soil profiles was sampled along a climate-vegetation transect on the dated Mazama pumice fall in central
Oregon. The <2 μ size fraction from each sample was characterized
with respect to the relative significance of amorphous and
crystalline components, and the individual minerals of the latter
group were...
Snowbrush (Ceanothus velutinus), red alder (Alnus rubra), and
bitterbrush (Purshia tridentata) are three important nitrogen- fixing
nonleguminous species. They commonly grow in association with
commercially important conifers in western United States and conceivably
could be utilized to add nitrogen to forest ecosystems. Nitrogen
15 gas was used to study nitrogen...
The understory vegetation was sampled in eight plant communities
of a Douglas-fir ecosystem to determine the organic matter
production and mineral composition.
Four sample sites were selected in each plant community and
the understory vegetation sampled using the method of quadrats of
successively increasing size. All herbaceous plants were separated...
Humus is one of the important factors controlling the soil
formation process. The nutrients released from it during the decomposition
process also affect the growth and reproduction of the
forest. The type of humus formed is influenced by the nature of the
forest litter and the environment in which it...
Six, recent clear cut areas were selected in the Douglas-fir
zone of the Western Cascade Range of Oregon to determine the
environmental and nutritional effects that snowbrush has on the establishment
and growth of Douglas-fir seedlings.
One thousand eighty milacre sample plots on the six clear cuts
were used to...
The effect of moisture stress and nutrients on the rate of growth
of wheat (Triticum aestivum L. Var. Gaines) seedlings was studied.
A special apparatus in which the moisture stress of several perlite
cells could be maintained constant by osmotic solutions was used.
Predetermined amounts of nitrogen were added to...
The objectives of this study were to establish a suitable method
for the measurement of the root cation-exchange capacity of conifer
seedlings, and to examine possible influences of this root characteristic
on nutrient absorption from a Bellpine soil under greenhouse
conditions.
The exchange sites of fresh, excised roots were saturated...
Soil erosion by mass wasting is the major problem on forest
lands of the Pacific Northwest, The clay fractions of soils from a
large number of sites in Oregon's Western Cascades were characterized
in order to determine the relationships of various clay materials to
mass movements. Each site was either...
The morphology, genesis, and classification of soils
forming in multiple tephra deposits of recent age from
Mt. St. Helens volcano in southwestern Washington Cascade
Mountains was studied.
Soils which occupied well drained and poorly drained
positions on the landscape were characterized according
to their morphology and the results of analyses...
Symbiotic associations are established between non-leguminous
(actinorrhizal) nitrogen-fixing flowering plants and two categories
of microorganisms: mycorrhizal fungi and a filamentous actinomycete.
The actinomydete induces nodule formation and produces nitrogenase,
the enzyme responsible for the reduction of atmospheric nitrogen to
a form available to higher plants. The mycorrhizal fungus is found...
Soils representative of several landscape units in the H. J.
Andrews Experimental Forest, Western Cascade Range, were sampled,
analyzed, and tentatively classified. Genetic inferences were
drawn relating soils to landscape position and other factors of soil
formation. Descriptive information and nutrient capital data were
provided to support ecosystem modelling efforts...
To obtain data on the decomposition of the forest floor, a battery operated electrolytic respirometer was developed making it possible to measure CO₂ evolution from field moist forest floor samples in situ independent of root respiration. Banks of four respirometers powered by two 12-volt batteries were installed in three old...
Decomposition of forest litter is a complex process
involving interactions between physical, chemical and
biological factors. As litter decomposes it is chemically
altered. Cation exchange capacities of litter represent a
means of characterizing the number of hydrophilic acid
groups. Some kind of soil-root ion exchange mechanisms are
utilized by the...
Shallow, rapid soil mass movements are common events and primary sources
of sediment in steep terrain of the Pacific Northwest.
Poorly vegetated debris deposits and scars resulting from landslides
remove land from the productive timber base, and are subject to
continuing erosion. To examine the impact of these events on...
Nutrient and particulate matter balances were established for five ecosystems dominated by Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] in the western Cascades, Oregon. Carriers of N and P were particulate matter (dust in precipitation and sediment in streams) and dissolved matter in both precipitation and stream water. The input and outflow...
Cultivated lilies include many garden varieties in addition to
the Easter lily, Lilium longiflorum Thunb. A popular member of
the garden group is Lilium speciosum Thunb., whose leaves can be
discolored by a virus symptom described as streak mottle. This
disorder is characterized by dashes of chlorotic tissue interspersed
with...
This thesis is based on an experiment in typewriting
which utilized specially designed audio-monaural
equipment for skill-building. The experiment was conducted
with students taking typewriting instruction at
the intermediate level at Oregon State University during
the Fall quarter, 1960. Three control and three
experimental classes participated and were compared on...
An experimental study was conducted with beginning typewriting
students to investigate the effects of two variables in proofreading
straight copy paragraph materials in the independent method of
proofreading. One was the influence of repetition which was examined
through the use of three different methods of reading. The second
was the...
Fluid-structure interaction (FSI) has been of significant research interest worldwide over the past several decades because of its variety of applications in both offshore and coastal engineering. Researchers analyzing FSI systems rely heavily on experimental tests in model scale in laboratories or large-scale sea trials. However, these tests are often...
The effects of roadbuilding, logging and burning upon stream
runoff responses to individual storms are evaluated for the Alsea
experimental watersheds, located in the Oregon Coast Range, The
parameters analyzed are peak discharge, induced peak discharge,
time-to-peak, and storm-runoff volume. The volume parameter is
further sub-divided into total, quick, delayed,...
A model is developed that allows the prediction of the stress-strain
distribution in a mixed carbide sphere pac fuel pin during
irradiation. The model is coupled with a previously developed model
for the thermal behavior of the pin. The one-dimensional (radial at
various axial locations) solution is for quasi-steady pin...