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...
Field studies designed to study residual effects from fertilizer
molybdenum were initiated in September 1971 on established grass-clover
pastures at ten sites in Western Oregon. Treatments were 0.0
and 1.12 kg molybdenum /ha on plots receiving 0-35-0-20S fertilizer (elemental sulfur-S) and 0.0, 0.56, 1.12 and 2.24 kg molybdenum /ha on...
Shoot apex senescence is defined as the collective progressive
and deteriorative processes which ultimately terminate the functional
life of the shoot apex. Senescence of shoot apices of Pisum sativum
L. 'Alaska' as measured by cessation of stem elongation was delayed
by removal of flowers and by treatment with gibberellin A₃...
The rate of the C¹⁴0₂ release from glucose, specifically labeled
with C¹⁴ at 1, 2, 3+4, and positions, was used to study the relative
participation of pathways of glucose catabolism in red beet slices.
Evidence was obtained which indicated that in mature red beets glucose
was catabolized mainly via glycolysis-tricarboxylic...
Sulfur-coated urea (SCU), a slow release nitrogen fertilizer,
may be economically competitive with conventional fertilizers, but
little is known of the mechanism of urea release from SCU and the
environmental factors which affect the urea release rate. Objectives
of this thesis were: (1) to determine factors which affect the rate...
The research presented in this thesis evaluated the effects of
uranyl (UO₂⁺⁺) upon the absorption of Li, Na, K, Rb, and Cl. Due
to the biological importance of Na and K, these two ions were
studied in the greatest detail.
The results of this research showed that, at UO₂⁺⁺ concentrations...
Incubation experiments with an acid poorly drained soil have
shown that the application of neutral soluble salts influenced the level
of extractable Mn. The application of a salt which lowered the soil
pH either increased the extractable Mn or retarded the oxidation
and/or fixation of extractable Mn. This effect was...
Detoxification of atrazine in soils results from both chemical
hydrolysis and microbial degradation.
Infrared analysis was used
to study the hydrolysis of atrazine upon interaction with soil
colloids
and to ascertain the existence of enol, keto, and protonated-keto
forms of hydroxyatrazine.
Evolution of ¹⁴CO₂ from ¹⁴C-atrazine
and ¹⁴C-hydroxyatrazine was indicative...
The ecological and silvicultural importance of snowbrush,
Ceanothus velutinus, in the areas west of the summit of the Oregon
Cascades was studied. Particular attention has been given its nitrogen-
fixing ability under both field and greenhouse conditions.
On west slopes of the Oregon Cascades snowbrush occurs above
2, 500 feet...