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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Pollution prevention strategies used by Oregon hospitals

Patel, Neha T. 24 September 2002 (has links)
Waste generated by the health care industry has been cited as a major source of toxic pollution, including mercury and dioxins, which poses a serious threat to public health. The purpose of this study was to investigate pollution prevention activities of health care facilities in Oregon related to environmentally preferable purchasing practices, recycling, mercury reduction efforts, and written policy. Surveys were sent to 57 hospitals in Oregon, 24 facilities responded (42.1 %). Results indicate that the following environmentally-preferable purchasing practices are being implemented: purchasing reduced hazardous material (92%); using recycled packaging (75%); and, using products made from recycled content material (83%). Other practices, such as the purchasing of cadmium-free red bags (25%), supplies shipped in reusable shipping containers (34%), and using minimal packaging (46%) are being implemented in a few hospitals. None of the hospitals are purchasing chlorine-free office paper. The majority of participating Oregon hospitals are recycling paper (96%), cardboard (96%), clear glass (67%), linens (87.5%), batteries (67%) and X-ray film (83%). Fewer hospitals are recycling plastics: #1 PET and #6 polystyrene (37.5%), #2 HDPE (42%), #5 polypropylene (33%). Fewer hospitals are also composting food (46%), computers and equipment (42%), fluorescent lamps (21%) and solvents/fixers (29%). Major barriers to recycling in hospitals include lack of established markets for some materials, limited space to collect the materials, and low employee participation. The majority of participating hospitals are reducing the purchasing of mercury containing products, replacing mercury blood pressure units and gauges, replacing lab and housekeeping chemicals, and pharmaceuticals. Fewer than 50% of then participating hospitals are replacing switches, recycling batteries and conducting an inventory of mercury sources. Few hospitals are checking drains and pipes for mercury contamination (13%), recycling fluorescent lamps (21%) and requiring vendors to disclose mercury content below 1% (17%). While most hospitals no longer purchase new mercury-containing devices, the cost associated with disposal of mercury as a hazardous waste is a major barrier to elimination. Hospitals located in urban areas in Oregon are more likely to implement pollution prevention strategies than rural hospitals. Nearly all Oregon hospitals lack a corporate policy on pollution prevention/source reduction, or written goals on waste volume reduction or waste toxicity reduction efforts. The few hospitals (8%) that have put policies in place have done so voluntarily, and with the full support from upper-level management. Based on theses findings recommendations include the following: 1) Establish a "Green Team" of hospital staff from diverse departments. This group can then strategize about courses of action for the facility with input from all responsible sectors. 2) Conduct a waste audit. This establishes a baseline of existing hospital waste and will help determine how to shape a waste minimization program and pollution prevention plan. 3) Pollution prevention education should be a top priority for all departments within each hospital including purchasing, nursing, housekeeping and top management. Many health care professionals are not aware of the link between the products and practices they choose and the environmental consequences of these choices. 4) Rural hospitals can join pollution prevention email list serves such as the Oregon Health Care Without Harm list (HCWHoregon-health.org) or the H2E list serve (www.h2e-online.org) to share, learn and identify practical strategies for pollution prevention and waste minimization. 5) Approach and involve upper level management to work with hospital "green teams" to develop and implement a hospital policy on pollution prevention. / Graduation date: 2003
82

A preliminary archaeological predictive model for the US 30 transportation corridor, Portland, Oregon To Astoria, Oregon

Kachadoorian, Lydia A. 04 February 2003 (has links)
This thesis is a preliminary archaeological predictive model and project-planning tool created for the Oregon Department of Transportation (ODOT) as part of a statewide planning effort to enhance the agency's ability to assess the potential impacts of highway projects on archaeological resources. This model addresses the archaeological sensitivity of the US 30 highway corridor from Portland, Oregon to Astoria, Oregon. The highway corridor is divided into 7 separate segments for management purposes and each segment is given a low, medium, or high probability rating for its potential to yield archaeological resources in this model. The ratings are accompanied by planning and maintenance recommendations to be integrated into a comprehensive planning document for the corridor. Probability determinations are based on State Historic Preservation Office (SHPO) archaeological records, physiographic data, dominant vegetation zones, General Land Office maps, ethnographic accounts, and historical records. The precise utility of this model is unknown because cross-tabulations that compare actual and model assigned presence or absence of resources have not been made. Low probability ratings are assigned to 27% of the corridor. Medium probability segments comprise 15% of the corridor. High probability rating account for 58% of the total length of the corridor. The segment with the highest site density is segment 2, averaging .63 archaeological sites per mile. The archaeological probability ratings were initially omitted from the Draft Corridor Management Plan of 1998, but have been included in the Final Corridor Management Plan of 1999. The predictive model results were incorrectly added to the document and consequently create false impressions. In the Final Corridor Management Plan the number of sites listed for segment 2 is incorrect. It is indicated that seven archaeological sites are present within the corridor, but the actual number is fourteen. Furthermore, the percentage ratings of low, medium, and high archaeological probability are erroneously provided for segments 3, 4, and 7 in the final plan. Ultimately this report has proven useful to ODOT archaeological staff, however signs indicate that the data provided to planning personnel has had little impact on project planning and design. / Graduation date: 2003
83

Work pants worn by loggers in Western Oregon, 1920-1970

Gullickson, Mark A. 25 May 2000 (has links)
With the arrival of European settlers to Western Oregon nearly 150 years ago came new methods of forest management. Early settlers' forest practices consisted of little more than harvesting what seemed an endless supply of timber. Forestry in the 20th century eventually incorporated such management concerns as re-forestation, biodiversity, wildlife sciences, recreation, and cultural resources. While forest practices in the Pacific Northwest changed dramatically during the 20th century, clothing worn by those most commonly associated with the field, the "logger," remained relatively unchanged. While much information has been published regarding the often over-romanticized life of the logger, information regarding the day to day-life and associative material culture remains almost nonexistent. As the 20th century economy in the Pacific Northwest became less dependent on the wood products industry, the culture and way of life for those whose lives centered around this once thriving industry began to disappear. My interest in this subject developed out of my personal experience working in the woods throughout the Pacific Northwest for seven years, as a forest fire fighter and park ranger for the Bureau of Land Management, and as an archaeologist for the U.S. Forest Service and Oregon State University Research Forests. In this study, I gathered collective memories from 18 individuals who logged throughout Western Oregon between 1920 and 1970. Informants were asked a series of questions pertaining to their logging careers and the clothing they wore. Often termed "old-timers," these informants served as the primary resource of information about work clothing worn by loggers in Western Oregon between 1920 and 1970. Published information describing the history of logging in the Pacific Northwest, photographs provided by informants showing them at work, the examination of catalogues from manufacturers of men's work clothing, and interviews with representatives of work clothing companies served as secondary resources. Published materials detailing work clothing worn by loggers is relatively nonexistent. Consequently, persons with first hand knowledge wearing logging work clothing are in many instances the only sources of information. Photographs furnished by subjects, showing them wearing their work clothing were collected as supportive material. While interviewing subjects for this project, additional questions beyond the scope of the project were asked. Subjects were asked related questions about other types of clothing they wore during their careers. Other areas of logging history and culture explored during interviews consisted of information about changes they observed in the technology of logging hand tools and machinery, land management and associative forest practices, and first hand experiences observing fellow workers severely injured or killed while working in the woods. With the passing of each "old-time" logger, a living connection between the present and the past, and the stories in between, are gone forever. This project helps to present a written record of some of these connections. / Graduation date: 2000
84

Investigations of soil morphology, hydrology, reduction-oxidation potentials, and stratigraphy on a selected hillslope in western Oregon

Verble, Kathy K. 01 June 1998 (has links)
Graduation date: 1999
85

Biological control of purple loosestrife Lythrum salicaria by two chrysomelid beetles Galerucella pusilla and G. calmariensis

Schooler, Shon 07 May 1998 (has links)
In the first part of this study we monitored the development of biological control of purple loosestrife Lythrum salicaria over a six-year period at Morgan Lake in western Oregon. In 1992, two beetles, Galerucella pusilla and G. calmariensis (Coleoptera: Chrysomelidae), were released to control the wetland weed at this test site. Our purpose was to estimate quantitative performance parameters that might be generally applied in monitoring biological weed control. Our six performance measures were: 1) biological control agent establishment, 2) the rate of increase of the agents, 3) the rate of spread of the agents, 4) the effect of the agents on individual target plants, 5) the effect of the agents on the population of the target plants, and 6) the indirect impact of the biological control agents on the local plant community. The beetles established viable populations that increased during the study with an intrinsic rate of increase (r), based on the growth rate in damage, estimated at 2.24/year. Within six years after introduction, the beetles spread to saturate the entire purple loosestrife habitat (4100 m��) around the lake. The rate of spread, estimated by calculating a diffusion coefficient (D), was 57.5 m��/year. Adult beetles made seasonal, exploratory movements up to 30 m away from the host plant stand into surrounding crop fields, which suggests a disturbance-free buffer should be established in the habitat surrounding the loosestrife stand. By 1997, both flowering success and median stem density (per 0.125 m�� plot) of purple loosestrife declined to zero. Mean above-ground biomass decreased to 8.4% of its 1994 level. Biomass of native plant species increased by only 3% between 1996 and 1997. Overall, G. pusilla and G. calmariensis reduced the abundance of the target plant at our site. Our monitoring methods were effective at quantitatively measuring the establishment, increase, spread, and damage of the biological control agent, the subsequent decline of the target plant, and the impact on the local plant community. The second part of our study used field and greenhouse experiments to assess non-target effects of two introduced biological control organisms (Galerucella pusilla Duftschmid and G. calmariensis L.: Chrysomelidae) on the economically important ornamental plant, crape myrtle (Lagerstroemia indica L: Lythraceae). Prior host specificity tests performed in the laboratory found that beetles fed, but were unable to complete their life cycle, on this non-target plant. However, there was concern over damage that might occur when the two plant species existed together. This study extended prior tests into a field environment in order to compare the physiological host range revealed in greenhouse tests with the ecological host range revealed in the field. We assumed, based on prior evidence, that the control agents would not complete development on the non-target plant, and therefore, when the non-target organism was isolated from populations of the target organism the direct effects of the biological control agents would be negligible. When the target and non-target organisms existed together, the magnitude of indirect effect of the target organism on the non-target organism via the control agent was expected to increase with: 1) decreasing distance between the target and non-target organisms, and 2) increasing dispersal capability of the control agents. As expected from prior studies beetle feeding and oviposition occurred on crape myrtle but the beetles could not complete development on this non-target plant in our greenhouse and field tests. Leaf damage inflicted by the beetle was lower on crape myrtle than on purple loosestrife plants used as controls and extensive defoliation to the non-target plant was limited to within 30 m from the edge of the purple loosestrife stand. Biomass of crape myrtle was significantly reduced near the stand compared with plants that remained relatively untouched at greater distances. Purple loosestrife biomass exhibited a greater reduction with decreasing distance from the source of beetle colonization. In this thesis we construct and implement strategies for quantitatively assessing success of biological control programs and risk of introduced biological agents to non-target organisms. Through these observations and experiments we hope to increase the predictability and safety of biological control programs. / Graduation date: 1998
86

Evaluation and use of a soil mineralizable nitrogen test to determine the fertilizer nitrogen needs of winter wheat grown in western Oregon

Baloch, Dost M. 31 July 1998 (has links)
Graduation date: 1999
87

The ecological consequences of the reduction of species diversity : experimental approaches

Allison, Gary William 16 January 1997 (has links)
The influence of loss of diversity on community dynamics and ecosystem functioning has recently received considerable attention. Although study of biodiversity has a long history within ecology, empirical investigations exploring consequences of loss have been rare. Because many factors confound diversity comparisons, experimental manipulations of diversity offer the most direct way of attributing cause to diversity loss. The effects of reduction in number of species will depend on the strength and sign of species interactions affected by loss of diversity. An experiment performed on a high zone, rocky intertidal community in which macroalgal diversity was manipulated demonstrated that effects of diversity loss will be highly dependent on which species are removed. However, effects of diversity reductions were strongest at the harsh end of a stress gradient where interactions were more positive. Thus, factors that affect the strength and sign of species interactions such as the degree of physical stress may serve as a rough guide to where the effects of diversity loss will be most severe. An assessment of the influence of diversity on community response to a strong physical perturbation was performed using an experimentally-induced thermal stress. Higher diversity treatments were most strongly affected directly by the stress because such treatments had higher abundance and therefore more biomass to lose. However, those same treatments recovered more quickly from the stress. Community recovery of initially low diversity treatments was slowed by persistence of non-typical states or slow recovery of dominant species. A simulation study was performed to assess the ability of different experimental designs to detect biodiversity effects. Our ability to predict consequences of changes in diversity will be dependent on our ability to distinguish the most influential biodiversity "components" within a system. This study uncovered a phenomenon that will be common in biodiversity studies: misidentification of one biodiversity component (e. g., an effect of a keystone species) as a different component (e. g., an effect of the number of species). I call this phenomenon "aliasing." Because of the complexity of biodiversity, experiments and observational studies will be highly susceptible to aliasing and, thus, results will require careful interpretation. / Graduation date: 1997
88

Use of livestock to improve the quality of elk winter range forage in northeastern Oregon

Clark, Patrick Eugene 28 May 1996 (has links)
The effects of late spring defoliation on the winter forage quality of bluebunch wheatgrass (Agropyron spicatum [Pursh] Scribn. & Smith), Idaho fescue (Festuca idahoensis Elmer) and elk sedge (Carex geyeri Boott) and the response of wintering Rocky Mountain elk (Cervus elaphus nelsoni Bailey) to changes in winter range forage quality were examined. The study included two experiments; a hand clipping experiment conducted on bluebunch wheatgrass and a sheep grazing experiment conducted on bluebunch wheatgrass, Idaho fescue, and elk sedge. Four treatments were applied to bluebunch wheatgrass in the clipping experiment: 1) the entire basal area of individual plants was clipped to a 7.6 cm stubble height during the mid boot phenological stage, 2) one-half the basal area of individual plants was clipped to a 7.6 cm stubble height during the mid boot stage, 3) the entire basal area of individual plants was clipped to a 7.6 cm stubble height during the inflorescence emergence stage, and 4) plants were left unclipped as a control. In early November, forage samples from each of the three clipping treatments exhibited increases in percent crude protein and percent in vitro dry matter digestibility compared to the unclipped control treatment. Clipping the entire basal area of bluebunch wheatgrass plants to a 7.6 cm stubble height during the mid boot or inflorescence emergence stage was more detrimental to plant vigor than clipping one-half the plant basal area during the mid boot stage or leaving the plants unclipped. There was some evidence that clipping one-half the plant basal area during the mid boot stage may improve plant vigor compared to no clipping. Differences in crude protein, in vitro dry matter digestibility, and dry matter yield from winter forage samples of bluebunch wheatgrass, Idaho fescue and elk sedge were detected between plots grazed by domestic sheep during the boot stage of bluebunch wheatgrass and plots where sheep grazing was excluded. No differences in winter elk utilization of bluebunch wheatgrass, Idaho fescue, or elk sedge were detected between the late spring sheep grazing treatment and sheep exclusion treatment. Plot occupancy by wintering elk was similar between plots grazed by sheep and plots where sheep grazing was excluded. Although, wintering elk did not appear to respond to the livestock grazing treatment, results from this study suggest small improvements in the winter forage quality of perennial grasses such as bluebunch wheatgrass can result following late spring defoliation. Forage conditioning treatments which produce even small improvements in forage quality may be important to the nutritional status of wintering elk. / Graduation date: 1997
89

Field management effects on the thermal stability and activity of soil enzymes in whole soil and aggregates

Bandick, Anna Katrina 01 May 1997 (has links)
Graduation date: 1997
90

Breaking seed dormancy in three western Oregon grasses

Trask, M. Melinda 12 July 1996 (has links)
Graduation date: 1997

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