Following the surface application of urea to soil, there is the potential for nitrogen (N) loss from ammonia (NH3) volatilization until sufficient rain or irrigation has moved it into the soil. Many studies measuring NH3 loss have used laboratory and microplot field studies. The limitation of these techniques is that...
The goals of this project were to determine 1) if liming controls clubroot, 2) the pH that must be attained to achieve commercially viable levels of control, and 3) how best to lime (materials, timing, incorporation strategies) to achieve that pH.
Following the surface application of urea to soil, there is the potential for nitrogen (N) loss from ammonia (NH3) volatilization until sufficient rain or irrigation has moved it into the soil. Many studies measuring NH3 loss have used laboratory and microplot field studies. The limitation of these techniques is that...
The overall objective of this three-year project was to provide farmers with updated fertilizer recommendations for snap beans. The goal was to maximize nutrient use efficiency without compromising bean yield and quality. This was accomplished by partnering with commercial bean growers to conduct on-farm research as well as conducting trials...
The market for organic vegetables is increasing. As conventional farmers transition fields to organics to meet this demand, there is a need for better organic nutrient management guidance, especially for nitrogen (N). Organic N management is more challenging than conventional N management due to a higher level of uncertainty surrounding...
This research has demonstrated that liming clubroot infected soils to a pH ≥7.1 is an effective practice for reducing both the incidence and severity of clubroot. Liming does not kill the pathogen but rather prevents disease spores from infecting the plant. This research demonstrated that highly reactive calcitic lime products...
Several new powdered limestone products that are more finely ground (smaller particle size distribution) than products historically used have become commercially available. A major factor influencing the effectiveness of a liming material is its particle size distribution, with smaller particles reacting more quickly. Because lime efficiency estimates for various particle...
Urea is a common nitrogen fertilizer for sweet corn production. This two year project evaluated commercially available urea additives for their potential to provide crop production and environmental benefits. Specifically, experiments were designed to evaluate the efficacy of urea fertilizer products containing a urease inhibitor (Agrotain Ultra), or nitrification inhibitors,...
The overall objective of this multi-year project is to maximize nutrient use efficiency without compromising bean yield and quality. This year’s project objectives were to: 1) evaluate crop response to P fertilizer at current soil P test levels in grower fields; 2) generate phosphorus (P) potassium (K), and nitrogen (N)...
Enhanced efficiency fertilizer (EEF) technologies have the potential to improve the crop N use efficiency (NUE) as well as minimize negative environmental losses compared to conventional fertilizers. The EEF fertilizer products consist of urea plus additives (to inhibit N loss). The major pathways for N loss in our sweet corn...
Although Oregon is the #2 snap bean producer in the US, yield of snap beans per acre is greater in Oregon than any other state (USDA NASS 2012). Despite the scale and importance of snap bean production in Oregon, almost no research has been done on phosphorus (P) utilization over...
The enhanced efficiency (EEF) products we tested in our study hold the potential to increase the nitrogen utilization efficiency of sweet corn as well as reduce nitrate leaching when all N fertilizer is applied before planting. However, this potential is limited by weather (i.e. large early season rainfall events), irrigation...
Weed interference is a major, ongoing pest problem in sweet corn and a diverse community of weeds persists until harvest in most fields. Impact herbicide was used for the first time in 2006 with great success, and a registration for Laudis was granted in November of 2007. These registrations have...
The goal of dissertation research was to use geochemical, statistical and geological methods to constrain and understand climate variability over several different time scales. Specifically, I have addressed three questions regarding past climate change: (1) how does the record of Irish cirque glaciers constrain the dimensions of the Irish Ice...
Due to a growing body of literature documenting declines in pollinator populations, there has been increased public interest in pollinator conservation. In urban and suburban landscapes, many gardeners and urban land managers are interested in gardening for pollinators, particularly bees. Simultaneously, many homeowners and municipalities are interested in other aspects...
During the past few decades, the U.S. Department of Energy (DOE) has made significant investments to improve nuclear data libraries, as the quality of this data impacts nearly all analyses of nuclear systems. Nuclear fission product yields are one component of these libraries, and are important for the analysis of...
Results from vegetation management trials involving horticultural crops conducted during the past year are compiled and reported by faculty members of the Oregon Agricultural Experiment Station, the Oregon State Extension Service, and colleagues who cooperated from adjacent states along with local enterprises. This work was conducted throughout Oregon and involved...
Results from vegetation management trials involving horticultural crops conducted during the past year are compiled and reported by faculty members of the Oregon Agricultural Experiment Station, the Oregon State Extension Service, and colleagues who cooperated from adjacent states along with local enterprises. This work was conducted throughout Oregon and involved...
Results from vegetation management trials involving horticultural crops conducted during the past year are compiled and reported by faculty members of the Oregon Agricultural Experiment Station, the Oregon State Extension Service, and colleagues who cooperated from adjacent states along with local enterprises. This work was conducted throughout Oregon and involved...
Crops were grown at the experimental farms using accepted cultural practices (within the limits of experimentation) or trials were conducted on growers' fields. Most experiments were designed as randomized complete blocks with three to five replications. Herbicide treatments were applied uniformly with CO₂ precision plot sprayers. Unless otherwise indicated, preplant...
Results from vegetation management trials involving horticultural crops conducted during the past year are compiled and reported by faculty members of the Oregon Agricultural Experiment Station, the Oregon State Extension Service, and colleagues who cooperated from adjacent states along with local enterprises. This work was conducted throughout Oregon and involved...
Ensuring long term water security is the essential pathway towards development, prosperity, and stability in Afghanistan. However, the country is faced with water challenges that can be ascribed to governance failure at multiple levels of governance rather than to the resource base itself. Hence, studying the water governance system in...
The Younger Dryas climatic event is a global phenomenon associated with a 1,000 year return to glacial conditions during the late Pleistocene period between 12,800 and 11,500 cal BP. Because of its significant effects on paleoenvironmental conditions in some parts of the world, archaeologists commonly seek to assess whether the...
Monophyly of the gomphoid-phalloid clade was confirmed based on multigene phylogenetic analyses. Four major subclades (Hysterangiales, Geastrales, Gomphales and Phallales) were also demonstrated to be monophyletic. The interrelationships among the subclades were, however, not resolved, and alternative topologies could not be rejected statistically. Nonetheless, most analyses showed that the Hysterangiales...
Terrestrial chronologies from southern Greenland provide a detailed deglacial history of the Greenland Ice Sheet (GIS). The northern GIS margin history, however, is less established. Here we present surface exposure ages from moraines associated with two large outlet glaciers, Petermann and Humboldt, in the northwestern sector of the GIS. These...
This dissertation explores one overarching question relevant to the
paleoclimate of the latest Pleistocene glacial cycle (approximately the last
130,000 years): “How did spatial and temporal evolution of ocean
temperature, both at the surface and interior, relate to other parts of the
climate system in the late Pleistocene?” Results from...
We review and synthesize the geologic record that
constrains the sources of sea level rise and freshwater discharge
to the global oceans associated with retreat of ice
sheets during the last deglaciation. The Last Glacial Maximum
(~26–19 ka) was terminated by a rapid 5–10 m sea
level rise at 19.0–19.5...
There are a number of problems associated with urban expansion and as cities continue
to grow the integration of green roofs can help to ease and offset many of them. This study
uses a combination of moss and Sedum as vegetation for experimental green roof sections in
order to test...
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Ed Peachy & AaronHeinrich
Maria Dragila & Gloria Ambrowaik
Andy Phillips & Hannah VanHoosen
This project is evaluating interseeding of crop crops to improve cover crop establishment after late harvested crops such as sweet corn and processing squash. In Project 1 at the OSU Vegetable Research Farm, a cover crop of oat and crimson clover produced the most cover crop biomass when interseeded at...
Rethinking the Dualism: Don DeLillo's White Noise and the Ecocritical Possibilities of the Nature/Culture Mix questions current applications of ecocriticism and offers that these applications are inadequate in dealing with the perceived nature/culture dualism. This thesis suggests that ecocritics need to stop thinking in dualistic terms, but instead must consider...
The purpose of the study was to demonstrate the effectiveness of a safety systems approach, so designed, to reduce instructional needs by the application of research to the conceptualization and development of a computer-assisted safety management program. Procedure Two hundred accredited schools served as the respondent population for the study....
This thesis brings together under one cover a survey of the
history of the real number pi along with a study of the present state
of its theory, application, and calculation.
Autonomous robotic agents are on their way to becoming in-home personal assistants, construction assistants, and warehouse workers. The degree of autonomy of such systems is reflected by the manner in which we specify goals to them; the abstraction of low-level commands to high-level goals goes hand-in-hand with increased autonomy. In...
Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional understanding of how individuals of those species interact with their environment, specifically how their movement is affected by human-induced changes. In order...
The purpose of this study was to investigate the interrelationships
between loneliness, college academic achievement, and locus of
control. The sample consisted of 97 subjects who were randomly selected
from those students living in the residence hall system at Oregon
State University.
Five null hypotheses were tested:
1. There is...
Polychaete annelids from 48 benthic samples containing over
2000 specimens were identified. Samples were taken with either an
anchor dredge or an anchor-box dredge from a 15 station transect
(44° 39. 1'N) that ranges from 800 to 2900 meters in depth. Sediment
subsamples were collected and analyzed for organic carbon...
Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that...
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. Gottschalk99, Dave Goulson6, Aaron D.
Gove100,101, James Grogan102, Mick E. Hanley103, Thor Hanson104, Nor R
This dissertation examines the impact of the German naturalist and literary figure Johann Wolfgang von Goethe’s ideas on twentieth century Anglophone plant morphology and biology. Goethe interpreted the organ forms of flowering plants as metamorphoses of each other. His literary, historical, and philosophical writings suggest themes of alienation from and...
In the midst of the sixth mass extinction, understanding wildlife disease spillover is critical to maintaining protected wildlife areas. Studying ecoimmunology and wildlife disease ecology helps to understand immune and disease traits in an ecological context, which is invaluable in preventing pathogen spillover between livestock and wildlife. To investigate this...
The results presented in this dissertation address a number of questions regarding late Pleistocene and Holocene ice-sheet and climate interactions, spanning disciplines involving paleoclimatology and atmospheric science. These studies use various techniques in geochemistry, climate modeling, and ice-sheet modeling to address ice- sheet response to climate and the attendant interactions...
The Brownian motion of micron-scale particles reflects the viscoelastic response of the local environment of the medium. Tracking the thermal fluctuations of these particles is a measure of the rheology of the material at the microscopic scale. This technique is called passive microrheology. Microrheology has been developed to assess the...
The deglacial behavior of the sub-Arctic North Pacific is poorly constrained, with many published records suffering from limited age control due to extensive post- depositional biogenic carbonate dissolution. Potential alternative dating methods could include the correlation of stable-isotopic and/or paleomagnetic secular variation records to an independently-dated regional template, however no...
Reconstructing the sensitivity of past climate to forcings, and of ancient glaciers and ice sheets to this climate, can allow us to better understand the range of climate and cryosphere behavior we may see in the coming centuries. The Arctic is a region of particular importance due to its well-documented...
Results from vegetation management trials involving horticultural crops conducted during the past year are compiled and reported by faculty members of the Oregon Agricultural Experiment Station, the Oregon State Extension Service, and colleagues who cooperated from adjacent states along with local enterprises. This work was conducted throughout Oregon and involved...
"What’s wrong with this AI?" Explainable AI (XAI) researchers are moving beyond explaining an AI’s actions, to helping users detect an AI’s failures. However this detection may not be enough—for actionability, we often need to pinpoint which part failed. We investigate how AAR/AI, a structured assessment process, supports users with...
This dissertation explores the engineering of carbon nanotube electronic devices using atomic force microscopy (AFM) based techniques. A possible application for such devices is an electronic interface with individual biological molecules. This single molecule biosensing application is explored both experimentally and with computational modeling.
Scanning probe microscopy techniques, such as...
The goals of this dissertation are centered on understanding changes in Earth surface and climate systems through the use of geologic proxies as records of past changes in these systems. Specifically, this dissertation (1) establishes a new chronology for retreat of the Ross Sea sector of the West Antarctic Ice...
The search for the stand density that optimizes growth and hence generates the maximum amount of wood is one of the philosopher’s stone in modern forestry. Since scientific methods were applied to forestry, numerous generations of foresters have studied the relations between stocking density and growth, obtaining diverse results and...
Karl Jordan (1861-1959) was an extraordinarily productive entomologist who influenced the development of systematics, entomology, and naturalists' theoretical framework as well as their practice. He has been a figure in existing accounts of the naturalist tradition between 1890 and 1940 that have defended the relative contribution of naturalists to the...
Hop (Humulus lupulus L. var. lupulus) is a diploid, dioecious plant with an extensive history of cultivation and use in brewing, as a textile, and for its therapeutic properties. Hop is prized for its ability to produce a variety of aromatic and flavor compounds, as well as compounds with anti-microbial...
Multi-robot teams offer promising solutions for many long term deployments in remote and dangerous domains, such as extraterrestrial or underseas exploration. However, long term deployments present many problems preventing robot teams from operating effectively. Learning over long time scales is makes it difficult to assign credit to robots' actions, as...
Although dam construction has been an integral tool in development initiatives for nearly a century, dams can have significant negative impacts on local residents, particularly those who are permanently displaced from their homes and must be resettled elsewhere. Dams have unique impacts on indigenous peoples. As a result, many dam...
This thesis seeks to better understand the most pressing cultural barriers to progress in the sustainability movement, and to offer suggestions for overcoming barriers. This research includes a two-year long case study of the sustainability movement at OSU, where the researcher coordinated projects encouraging behavior change. Despite increasing severity and...
Calcium (Ca) is an essential macronutrient that is increasingly recognized as a biogeochemical factor that influences ecosystem structure and function. Progress in understanding the sustainability of ecosystem Ca supply has been hampered by a lack of information on the various forms and pools of Ca in forest ecosystems. In particular,...
It is desirable for complex engineered systems to perform missions efficiently and economically, even when these missions' complex, variable, long-term operational profiles make it likely for hazards to arise. It is thus important to design these systems to be resilient so that they will actively prevent and recover from hazards...
Biodiversity loss is of global concern, and is due in part to deforestation and high consumer demand for wood and wood products. The neotropical tree species Cedrela odorata (“Spanish cedar” or “cedro”) is economically valuable for its wood and faces threats of overexploitation. Due to strong similarities in wood features...
This dissertation presents novel, field-activated smart material systems for the actuation and control of autonomous robots. Smart materials, a type of material whose properties can be changed with an external stimuli, represent a promising direction to expand upon existing robotic control and actuation methods, particularly in the sub-fields of soft...
There is growing commercial interest in the use of multiagent systems in real world applications. Some examples include inventory management in warehouses, smart homes, planetary exploration, search and rescue, air-traffic management and autonomous transportation systems. However, multiagent coordination is an extremely challenging problem. First, information relevant for coordination is often...
Spectrometric detection systems for gas chromatography
(GC) based on gas phase ultraviolet absorbance
and fluorescence measurements have been developed and
evaluated in this research. Polynuclear aromatic compounds
(PNAs) are selectively detected by these systems.
Limits of detection for PNAs range from 4 ng to 90 ng
for absorbance determinations, and...
The objective of this dissertation is to enhance the monitoring of forest ecosystems through the utilization of remotely sensed data to address the exigencies posed by the Anthropocene. On a global scale, rising temperatures and fluctuating precipitation patterns have strained forests and produced shifts in natural disturbance regimes. Additionally, the...
The body of work aims to contribute to the area of Quantitative analysis in Environmental Sciences, and is focused on the microbiome. The underlying theme for the dissertation is methods and workflow. The unique bioinformatics workflow used for the analysis of genomic data was used to answer distinct and pressing...
Bacterial blight (Xanthomonas arboricola pv. corylina) (Xac) of hazelnut (Corylus avellana L.) was described first in Oregon in 1915 and is now recognized as a damaging disease of young hazelnut trees worldwide. Stressed hazelnut trees in conditions such as planting on marginal sites, and trees between 1 and 4-years-old are...
After decades of expert-based modernization efforts that have had profound negative impacts on human and environmental health, Ecuador is currently pursuing a rights-based, participatory development paradigm known as sumak kawsay or "the good life". Despite its promises of inclusion and interculturality, this approach continues to rely on highly trained specialists,...
In real networks, identifying dense regions is of great importance. For example, in a network that represents academic collaboration, authors within the densest component of the graph tend to be the most prolific. Dense subgraphs often identify communities in social networks. And dense subgraphs can be used to discover regulatory...
By means of a case study and historical analysis, this dissertation examines the past and present of avian influenza. By integrating disconnected histories of human and animal influenza, this dissertation links historical insights with the concerns of contemporary avian flu science. It is not only a natural history of avian...
This dissertation explores the structural dynamics of human understanding and particularly the concept of meaning and its connections to concepts of ultimate ground, necessity and contingency, language, and perception. It focuses on the history of the concept of meaning in early twentieth-century European physics and philosophy, through an analysis of...
By 1900 domestication was a promising, if somewhat vexed, subject in biology. Volumes had been written about domestication, but little serious scientific inquiry was directed toward the phenomenon. Expertise lay with practical men, primarily breeders and fanciers. The bulk of scientific commentary on domestication came from anthropologists who derived theories...