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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.
21

Mobile Processing: Developing Appropriate Technology for Pastured Poultry Producers

Stokes, Sarah Diane 06 February 2007 (has links)
N/A
22

Population Characteristics and the Effects of Hunting on Black Bears in a Portion of Northwestern Montana

Thier, Timothy Joseph 23 September 2011 (has links)
Prior information regarding the status of black bears (Ursus americanus) in Hunting District 100 in extreme northwestern Montana was confusing and oftentimes conflicting. To gather information on the population and the effects of hunting, especially during the spring hunting season, 13 black bears were radio-collared and monitored during 1986 and 1987. An additional 15 bears were marked and released. Information was gathered on the age and sex structure of the capture sample, survival and mortality rates of marked bears, reproduction, home range sizes, and hunter technique and effort. A density estimate of 1 black bear/15.4 km2 for the study area was determined. The age structure of captured bears was comprised primarily of adult males, which is generally recognized as indicative of a lightly or unexploited population. However, the mortality of marked bears due to hunting was found excessive. A decrease in the number of bears captured from 1986 to 1987, the large proportion of marked bears killed, and the 1987 spring observation data, all indicate that the study area population was well sampled by trapping. A reproductive rate of 0.70 cubs/female/year was determined, with at least 1 female not producing a successful litter until the age of 7. The mean home range size for adult males (5+ years) using the minimum convex polygon method was 98.7 km2 with a range of 35.5 to 192.6 km2 (n ;: 7). The home range size for adult females was 45.8 km2 with a range of 17.5 to 107.4 km2 (n = 4). Driving open roads was the primary hunting technique used during the spring hunting season. Thirty-nine percent of the bears killed during the spring season were shot within 100 mof an open road, while 66% of the bears were killed after first being observed from an open road.
23

An Assessment of Livelihood Security in International Community-based Wildlife Conservation Projects

Perez-Watkins, Monica Antonia 13 February 2013 (has links)
Strategies for human livelihood security and wildlife conservation often conflict, especially in rural and impoverished areas where wildlife and their habitats are important sources of livelihood. Community-based conservation approaches to wildlife conservation seek to remedy this conflict. Still, problems persist and alternative forms of livelihood are often not generated or accounted for in community-based projects. Therefore, it is important to understand the extent to which and specific ways livelihood security are incorporated into community-based wildlife conservation projects. This thesis uses qualitative methods to examine the extent to which livelihood security is incorporated into community-based wildlife conservation projects. Specifically, I assess whether and how well various subcomponents of livelihood security, which I identify as income, non-monetized benefits and access rights, representative participatory management, and food security, are incorporated into projects from developing regions around the world. My content analysis and rating of the quality of evidence of 27 published case studies revealed that various subcomponents of livelihood security are often incorporated into community-based wildlife conservation projects, though the subcomponents are often only weakly or moderately incorporated and sometimes are not incorporated at all. Among the four subcomponents of livelihood security, representative participatory management is incorporated into the projects to the greatest extent and food security is incorporated the least. Although case studies might mention livelihood security, in one-quarter of such instances, no evidence was provided that a particular subcomponent was actually incorporated into the project. Still, livelihood security was found to be incorporated to a moderate or strong extent in slightly more than one-third of instances. Recommendations to better incorporate livelihood security into wildlife conservation projects are provided for project facilitators, including non-governmental organizations, funders, and government agencies.
24

NEST SITE CHARACTERISTICS OF LEWISS WOODPECKER (MELANERPES LEWIS) IN RIPARIAN SYSTEMS OF WESTERN MONTANA

Fylling, Megan 18 September 2013 (has links)
The Lewiss Woodpecker (Melanerpes lewis) is known to breed in ponderosa pine, cottonwood riparian, aspen, and burned conifer forest types, but is declining in much of its range throughout the U.S. and is listed as a Level II Species of Concern in Montana. In western Montana, Lewiss Woodpeckers commonly breed in riparian bottomlands, but information on characteristics of their preferred nesting habitat within these areas is lacking. I studied nesting habitat use by Lewiss Woodpeckers in two important breeding areas in cottonwood-dominated riparian forest along the Clark Fork and Bitterroot rivers in western Montana. I found 55 nests during the summer of 2012, and measured vegetation characteristics around 38 of those nest sites as well as 30 randomly located sites within the same forests. My main objective was to examine nest-tree, local, and landscape habitat characteristics of Lewiss Woodpeckers at nest sites and random sites to determine whether sites used in western Montana river systems were a nonrandom subset of bottomland conditions and whether used conditions were similar to those reported from other parts of their geographic range. Logistic regression models were developed based on used sites and available sites within the study area. Results showed that Lewiss Woodpeckers used larger snags in areas with relatively high percent shrub cover and relatively high snag density per hectare. Snags provide perches to forage from, cavities for nesting, and an open canopy, while the shrub understory supports arthropod prey. From a landscape perspective, Lewiss Woodpeckers nest sites were closer to agricultural fields than were randomly located sites, suggesting adjacent fields were preferred. Information from this study will be disseminated to land managers and private landowners, recommending desired vegetation conditions to benefit this species, including snag retention. To ensure that conditions suitable for Lewiss Woodpecker are maintained in perpetuity will also require management of the river system in its entirety.
25

A Comparison of Storm Hydrographs from Small Urban Watersheds with Different Land Use Patterns in Baton Rouge

Walker, Josey Wade 12 July 2002 (has links)
Statistics gathered by FEMA indicate that nine of ten federal disasters are related to flooding. Research has demonstrated that increases in flooding can be contributed to urbanization or the construction of new residential and commercial developments (Anderson, 1970; Arnold & Gibbons, 1996; Putnam, 1972). New development has two main problems associated with it. First is the increase in impervious surfaces due to new parking lots, buildings, and streets (Booth & Leavitt, 1999; Seaburn, 1969). Second is the elimination of natural vegetation, which reduces evapotranspiration and lowers the soils ability to absorb precipitation (Hewlett, 1982). This study first demonstrates the relationship between land use and land cover characteristics associated with urbanization to hydrograph statistics, specifically time to rise and total rise. Secondly to create predictive models of watershed behavior based on these measures. Time to rise is the time between the inception of a storm and the initial rise of stream stage. Total rise is the total rise in stage to its peak, during the entire storm. This study represents a new geospatial approach for studying these relationships. The study first established a GIS database of land use and land cover characteristics. The second phase performed regression analyses of the hydrograph response variables with the land use and land cover characteristics as independent variables. There were statistically significant relationships between residential development, commercial development and roads with the response variables, time to rise and total rise. As development increases time to rise decreased and total rise increased. The percentage of forest land use, land maintained as contiguous forest, was correlated with total rise. As the percentage of forest land use increased the total rise decreased. This study demonstrates some univariate models that show direct relationships between land use and land cover characteristic and hydrograph response.
26

Evaluation of in Situ Bioremediation Approaches in Meeting International Standards for Organic and Residual Metals Toxicity in Soils

McDonald, Jason Allan 06 August 2002 (has links)
Drilling fluids and muds are an essential component of the rotary drilling process used to drill for oil and gas on land and in offshore environments. However, the bioaccumulation of petroleum contaminated soils/drilling mud due to oil and natural gas exploration has posed a major environmental concern due to its prolonged environmental persistence and its leachability below the rhizosphere. The main objectives of this research were: (i) To assess initial toxicity of drilling mud and related contaminated soils from an agricultural setting in Galliano, Sicily (Phase one) and (ii) To develop a low intervention bioremediation approach using bioplug technology to ensure that the soil/drilling mud has met U.S. and international soil/ground water quality standards by performing a microcosm study (Phase two). Total petroleum hydrocarbon content of the drilling mud reduced to 617.0±176.0, 446.0±195.0, and 533.0±138.0 mg/kg from 5000.0±530.0 mg/kg after treatment via mixing (84.2-95% reduction). The PAH and phenol concentration of the drilling mud resulted in a 97-99.5% reduction via mixing (5d study) and 69.4-77.9% reduction via in situ treatment (40d study). The metals of concern for the drilling mud are cadmium and selenium. Both metals had exceeded Italian and La DEQ soil leachability standards, which were established at 0.005 mg/L for cadmium and 0.010 and 0.050 mg/L for selenium, respectively. In situ bioremediation was performed on a cross-section of Italian soil/mud to test the effectiveness of bioplug technology. Total petroleum hydrocarbons had reduced from 217.12±43.38 and 149.68±45.51 mg/kg to 15.16±3.35 and 34.27±15.86 mg/kg for the control drilling mud test beds, and from 89.20±67.42, 141.71±64.80, and 197.87±77.38 mg/kg to 5.24±6.15, 15.02±10.20, and 9.65±9.37 mg/kg for the experimental drilling mud test beds, respectively. The efficiency of degradation for control and experimental setups were 85.1±11.2% and 92.9±3.0%, respectively. Overall, the microcosm experiment indicated that a significant reduction in total petroleum hydrocarbons had taken place for the drilling mud using bioplug technology and will be installed at the Italian site.
27

Mitigation Strategies for the Removal of Rinsate Organics and Lithium-Based Dyes from Textile Effluents

Huddle, Kathryn W. 28 October 2002 (has links)
Governmental agencies have set regulatory values on the concentration of dye-related color that can be released in textile mill effluents. A proprietary biotic and abiotic technology treatment train was built at a candidate facility in northwestern Georgia to reduce the organic content and dye-related color content in the textile mills effluent. Laboratory experimentation began with bench scale 4 L immobilized microbe (IMBR) bioreactor tests to biologically treat primary wastewater streams, namely skein dye and space dye, from this candidate facility. The biological treatment reduced the organic content levels, expressed as chemical oxygen demand (COD), from 3185±30 to 290±20 mg/L (COD reduction rate: 43.21±0.1 mg/L/h) in the skein dyeing effluent and from 5430±30 to 550±120 mg/L (COD reduction rate: 72.8 ± 1.3 mg/L/h) in the space dyeing effluent; however, the biological process did not remove all of the color from the effluent sample. An ozonation unit was added to the biological treatment process to aid in color reduction. The ozonation successfully reduced the residual color in both primary effluent streams. The skein dyeing effluent was reduced from 4.9 to 0.3 mg/L of residual color (color removal rate: 0.069 mg/L/h). The space dyeing effluent was reduced from 16.0 to 1.5 mg/L of residual color (color reduction rate: 0.21 mg/L/h). Both organic content and color removal exhibited >89% reductions. However, to produce water devoid of color from the effluent samples, activated carbon was added and filtered out to further clarify the ozone treated water. The resultant water was of recyclable quality. These laboratory processes were then adapted to create a commercial scale technology treatment train at the candidate facility. The commercial unit, operating at 110 gpm (gallons per minute) with a system hydraulic retention time of 41.6 hours, had reduction levels of >78% for both organic content reduction and color removal. These levels were acceptable treatment levels with the resultant effluent successfully recycled into the dye house processes. Thus, recyclable process water was produced from the effluent waters of the candidate textile mill facility.
28

Influences on State-Level Policies for Wildfire Risk Reduction

Valiantis, Marios Anastasis 03 April 2003 (has links)
Wildland fires are part of the United States history and culture. The human dimension of State wildland fire management, - the relationship of people and wildland fire in America- is an important and driving force in how federal and state agencies respond to wildland fire, now and in the future. In many ways, the critical element for the management of wildland fire is the management of people, communities, and organizations. Explosive growth in the wildland-urban interface puts entire communities, their associated infrastructure and the socioeconomic fabric that holds communities together at a high risk from wildland fire. Year after year fires are getting worst. The risk now is even bigger since more people live in the wildland-urban interface. The 2000 fire season highlighted the vulnerabilities of these wildland-urban interface communities, including industries, businesses, occupational groups, families, and individual citizens. This research attempts to determine the influences on state-level policies for wildfire risk reduction in the wildland-urban interface. All fifty States were selected to be studied in terms of their policies on wildfire risk reduction. Data was collected from the States in a survey form, and then analyzed to determine what factors may influence the states wildfire risk reduction polices. This research is an important first step in understanding the choices, approaches and specific activities undertaken by state decision-makers facing unprecedented threats from catastrophic wildland fire.
29

Factors Affecting Participation in City Recycling Programs

Lockhart, Stacy Marie 03 April 2003 (has links)
Recycling consists of diverting or recovering materials from the solid waste stream that would otherwise end up returning to the environment as a potential source of pollution. These collected materials are then used as raw materials in the manufacture or assembly of a new product or package. Over the years the amount of municipal solid waste being generated per person has steadily increased. Waste disposal costs are also increasing, making recycling even more important. To address this issue cities are developing recycling policies or plans. The type of plan varies according to the area; as of this time there are no national recycling standards or legislation being imposed. The Environmental Protection Agency is currently encouraging state and local governments to adopt a recycling program to reduce the amount of municipal solid waste being sent to landfills and incinerators. This study attempts to determine the types of municipal recycling programs and the success of those programs (measured by the participation rate) that have been instituted by cities. State capitals were selected as the cities to be studied in terms of their recycling programs and participation rates. Data was collected from these cities in both survey form and through the United States Census Bureau and 1991-1992 Green Index. It was then analyzed to determine what factors, if any, are associated with participation in the recycling programs in these cities. Significant correlations were found between participation and median value of owned homes, percent renter occupied housing units, percent bachelors degree or higher, and main type of recycling program. The municipal solid waste fee policy variable was not found to be significant but was determined to still be relevant to the study due to previous research and a significance level below .10.
30

Toward a Sustainable Energy Future? A Comparison between U.S. and European Energy Sectors

Moehner, Annett 03 April 2003 (has links)
Since 1987, the concept of sustainable development, which tries to combine economic, social and environmental concerns into one benign development model, has become increasingly popular worldwide. To explore and explain the differences in accomplishing sustainable development, this thesis looks at one specific aspect: the energy sectors in the United States and the European Union. After giving an overview on the political and theoretical aspects of sustainable development, the various sustainability dimensions in the energy sector are explored. The following four reasons which warrant the change of the current fossil fuel intense energy sector are discussed: first, air pollution; second, insecurity of energy supplies; third, ultimate exhaustion of fossil fuels; and finally, climate change. Following the development of the methodology, various statistical tests are performed using a variety of indicators. Using Wilcoxon?s rank sum test significant differences between the U.S. and the EU energy sectors are discovered in energy intensity, carbon dioxide emissions, as well as per capita energy consumption in the various energy end-use sectors. Afterwards, a Sustainable Energy Index (SEI) is developed identifying Austria, Sweden and Finland as having the most sustainable and Wyoming, Alaska and West Virginia as having the least sustainable energy sectors. In addition, through regression analysis, energy intensity, share of renewables and energy consumption in the transportation sector are determined to have the greatest impact on carbon dioxide emissions. After the discussion of the SEI policy recommendations are developed, whose prompt implementation is desirable given the global rise in energy consumption and the negative consequences of climate change. Finally, a conclusion is drawn that no country or state has yet achieved a sustainable energy sector. Nonetheless, it was observed that, in general, European Countries scored better than American States, which can be attributed to better energy and environmental policies.

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