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The localization of the United States sugar beet seed industry with emphasis on the Willamette Valley
No full textThis investigation has analyzed and described the impact of
place on one of man's activities -- the production of sugar beet seed.
It is apparent that in this activity man's relationship to the earth is
especially close and dependent upon a number of factors. These
are localizing factors. Sugar beets grown for seed are sensitive to
a number of environmental elements, particularly to the physical
element of temperature. Relative compatibility with certain established
farming systems and the establishment of seed producing organizations
in places favorable for sugar beet seed production are
other localizing factors. Since the market for sugar beet seed is
tightly controlled by contracting, and since the seed producing agencies
have been established in certain favorable areas, and since
quantity needs are rather static, it is probable that sugar beet seed
production will continue to be localized in the present production
areas. Furthermore, no great increase in quantity of production
can be expected.
The long, relatively mild winters with temperatures favorable
to development of the reproductive phase of growth in the sugar beet
have made the Willamette Valley of Oregon one of the two chief sugar
beet seed producing areas of the United States. Because it is the
place offering the best opportunity for total or complete reproduction
in all varieties, the Willamette Valley is the foremost producer of
seed of bolting resistant varieties of sugar beets. For the same reason,
it is the most prominent place for producing seed breeders'
elite and stock seed for increase. It is probable that these aspects
of the United States sugar beet seed industry will remain localized to
the Willamette Valley.
The Willamette Valley has ample land on which sugar beets for
seed could be raised should demand for seed ever warrant expansion.
Sugar beets for seed compete favorably with other crops grown on the
Valley's best soils; the present situation indicates that the same kind
of competition could be carried to any suitable part of the Valley.
With the only slight expansion now taking place, localization within
the Willamette Valley will likely remain within a radius of 30 to 40
miles of Salem, and principally on a north -south axis on the more
suitable alluvial soils
Contributions of ammonia-oxidizing bacteria and archaea to nitrification in forest soils
Get PDFPrior to 2005, ammonia oxidation, the first step of nitrification, was thought mediated mainly by ammonia-oxidizing bacteria (AOB). However, the discovery of Thaumarchaeota carrying the genes coding for the ammonia monooxygenase (AMO) enzyme led to the discovery that ammonia-oxidizing archaea (AOA) also contribute to nitrification. Despite the uptick in studies on nitrification following the recognition of AOA, the relative importance and the contribution of AOA and AOB in different ecosystems, and the factors controlling their abundance and activity, have not been well understood. Because nitrogen (N) cycling is mediated by microbes and controls the net primary productivity in forests, and nitrification is the rate controlling step in N cycling, it is important to have a better understanding of nitrification in forest ecosystem, especially the abundance and contribution of AOA and AOB in forest soils.
The objective of this study was to determine nitrification activity and nitrifier abundance in forest soils. I wanted to know: (i) if the inclusion of red alder influences
the distribution, total nitrification activity, and relative contribution of AOA and AOB to nitrification; (ii) if pH and substrate concentration influence the distribution and activity of ammonia oxidizers, and if so, (iii) what is the relationship between these two factors and nitrification.
The study selected soils from stands of red alder (Alnus rubra Bong.) and Douglas-fir (Pseudotsuga menziesii Mirb. Franco) at three sites in Oregon (Cascade Head, the H.J. Andrews, and McDonald Forest) that had a soil pH range of 3.9 to 5.7. The abundances of AOA and AOB were investigated using quantitative PCR (qPCR) by targeting the amoA gene. Nitrification activity was evaluated by nitrification potential in a slurry assay and nitrification rate in whole soil. Activity of AOA and AOB was differentiated by using octyne, which inhibits the AMO enzyme in AOB but not AOA.
Nitrification activity and octyne-resistant activity (AOA) were significantly higher at Cascade Head than at the H.J. Andrews and McDonald Forest and greater in red alder compared with Douglas-fir soils. Whole soil nitrification rate was stimulated by high NH₃ concentration (10 mmol kg⁻¹ soil) addition but not by low NH₃ concentration (1 mmol kg⁻¹ soil). At the high concentration of NH₃, both AOA and AOB responded, and nitrification was highest at McDonald Forest, followed by Cascade Head and the H.J. Andrews. There was strong evidence that soil pH was an important factor controlling AOA but not AOB abundance, and the AOA to AOB ratio decreased with increasing soil pH. Collectively, the data indicated that nitrification was mainly driven by AOA in acidic forest soils (pH < 5)
Design of an electrical analog for spherical wave propagation in solid elastic media
Get PDFWith the advent of underground testing, the study of the propagation of seismic signals has become of great importance. This thesis investigates the design of electrical analogs to represent the propagation of seismic waves. The analogs developed allow for the study of the effects of variations in the characteristic constants of the medium through which the wave propagates and further allow for the characteristics of the source to be imposed upon the compressional displacement propagation. It is assumed that the source may be represented by a spherical radiator and by solving the wave equation in spherical coordinates, the transfer function for the wave is obtained. The design of the analog is based on this transfer function and through the use of network synthesis, a lumped element network is synthesized. Variation of the elements in the synthesized network will permit the study of the effects of variations in velocity. Poisson's ratio, range, size of the radiator, and excitation functions on the compressional wave propagation. To include the effects of multiple layering, a second analog was designed. This was accomplished by connecting, in tandem, analogs representing single layer of specified thickness. The individual stages of this analog were synthesized using a different method from the one used in the synthesis of the first analog in that they were terminated. The application of the second analog is restricted to the case for which we can assume, within reasonable error, that the spherical wave approaches a plane wave in character
Child guidance attitudes of parents who have children in cooperative nursery schools and those who do not
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Language Differences between Women and Men and the Attribution of Leadership
Get PDFThis research addresses the perception of leadership attributes in light of evaluator and target gender. It specifically investigates whether there is a difference in language usage when the evaluator is female versus when the evaluator is male. Two studies were conducted. A pre-test used instrumental development drawing from studies conducted by Bem (1974) and Berlo et al. (1969). The pre-test sampled a population of 56 students in a Small Group Problem Solving class at Oregon State University and used a survey to determine the top six gender attributes used to describe women (Self-reliant, Sensitive, Understanding, Warm, Affectionate, and Cheerful) and the top six gender attributes used to describe men (Analytical, Strong personality, Competitive, Loyal, Assertive, and Dominant). The present study consisted of a survey that placed the 12 attributes on semantic differential scales. A population of 54 students in a Small Group Problem Solving class at Oregon State University used the scales to indicate to what degree the target displayed the attribute in question. The gender of the evaluator and target were coded and six group comparisons were run to determine measures of statistical significance. Significant results were found for 13 out of 96 individual attribute comparisons. Because only a few individual attribute comparisons were found to be significant, future research could return to Bem’s (1974) study and replicate it in new populations to determine its validity and reliability
Survival and nest site characteristics of translocated mountain quail on Steens Mountain, Oregon
Get PDFMountain Quail (Oreortyx pictus) populations have declined in the eastern portion of their range during the last century. However, few studies have investigated the nesting habitat and survival of Mountain Quail translocated into an area from which they have been extirpated. We translocated 217 wild Mountain Quail (Oreortyx pictus) from southwestern Oregon to Steens Mountain in southeastern Oregon to re-establish a population in this former part of their range. We measured habitat characteristics at 45 nest sites and 90 random sites to identify which habitat characteristics are important in Mountain Quail nest site selection. We found that canopy cover of shrubs, trees, and rocks, and shrub height 8 m from the nest were the 2 most important characteristics influencing Mountain Quail nest-site selection. Mean shrub height at nest sites was approximately 1 m tall and mean canopy cover was 28%. Managing habitat for shrubs of this height and a similar density of canopy cover will increase habitat suitable for Mountain Quail reproduction. When selecting future release sites, shrub height and canopy cover should be of primary consideration.
In addition to determining what habitat attributes Mountain Quail select for nesting, we also estimated survival rates for 135 radio-collared Mountain Quail for the 5-month period following translocation and looked at the effects of year, sex, time, linear and quadratic time trends, body condition, and weather covariates to see if they explained variation in survival rates. Year, sex, and a quadratic time trend were the most important factors explaining variation in survival in this study. Survival was higher in 2005 than 2006 and was higher for females in both years of the study. Survival was lowest during the first 2 weeks after the release suggesting that improving survival during this initial time period may improve overall chances of a successful translocation. Selecting release sites that provide adequate cover from raptors and other predators may be critical for survival of Mountain Quail following a translocation
Improving wood strength and stiffness through viscoelastic thermal compression
Get PDFThe objective of this research project was to increase the density, strength, and stiffness of two low to medium-density diffuse-porous hardwood species. Wood used in this study was processed using a method of wood densification known as “Viscoelastic Thermal Compression” (VTC). The VTC process is a three phase treatment which incorporates saturated steam treatment, mechanical compression, and a heat treatment. The strategy of the VTC process is to increase the density, strength, and stiffness of wood through non-destructive means. The two hardwood species chosen for this study were 7-year old Eastern cottonwood (Populus deltoides) and sweetgum (Liquidambar styraciflua) from the Pensacola, Florida area. The primary justification for this research was to test the suitability of VTC processed wood for future use in a high-strength structural composite. Analysis of VTC processed Eastern cottonwood has shown increases in density, MOE, and MOR of up to 178, 254, and 156 percent, respectively. VTC processed sweetgum showed increases in density, MOE, and MOR of up to 168, 213, and 182 percent, respectively. Both species exhibited increases in MOE and MOR which were approximately proportional to increases in wood density. Data obtained from this research project was used to develop equations to estimate the potential increase in wood strength and stiffness that can be achieved with the VTC process. Eastern cottonwood control specimens showed statistical differences in wood density as a result of vertical location. The upper stem locations were of higher density than the lower sections. Controls from the upper stem were found to contain a greater percentage of branchwood and earlywood vessels. A significantly smaller lumen diameter and presence of a gelatinous layer was seen in the latewood regions of the upper stem controls. This resulted in thicker lumen cell walls in the longitudinal fibers, which may have contributed to the wood density increase seen. Sweetgum control specimens showed no statistical difference in wood density as a result of stem location. The findings from this research showed that significant gains in wood strength and stiffness could be obtained with the VTC process, without causing cell wall fractures. These results were seen in two low to medium-density, diffuse porous hardwood species. Similar results could likely be seen in other species, both hardwood and softwood, providing the same procedure is followed. VTC processed wood shows potential for use as a high-strength laminate in a composite product