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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.
1

A mechanisation study of systems for the use of straw

Magowan, T. J. January 1987 (has links)
No description available.
2

Current real estate development industry usage of sustainable forestry products in the Southeast

January 2012 (has links)
0 / SPK / specialcollections@tulane.edu
3

Linking Individual Biological Outcomes to Resource Use

Ayers, Christopher Ryan 15 August 2014 (has links)
Minimum resource requirements support population persistence; however, ecologists and conservationists often want to identify factors that improve biological outcomes of animals. The population-level approach common in wildlife-resource studies limits our ability to draw inferences about the importance of resources and other factors by failing to link them with individual fitness. Measuring individual-based biological outcomes and resource use helps determine variation in mechanistic relationships between animal fitness and behavior. I suggest using direct metrics of resource use such as food consumption and distance traveled, to avoid errors with estimating resource availability. I summarize these concepts in an analytical framework for modeling relationships between resource use and fitness to guide readers toward effective study designs. I also describe constraints on an animal’s ability to use resources freely, which must be considered when modeling these relationships to account for additional sources of variation in biological outcomes. I investigated effects of resource use on body condition, survival, and reproduction using field data from four species of vertebrates. I found that using multiple predictor metrics to model biological outcomes allows comparison between factors affecting fitness. In general, factors more closely relating to energetics (e.g., movement pattern or distance traveled) were more useful predictors of animal outcome than metrics of habitat use or selection. Management and conservation efficiency can be improved by focusing efforts on preventing detrimental risks and threats, and supporting less stressful access to beneficial resources rather than supporting average population habitat use without consideration of biological outcomes. Improving the study of ecology depends in part on our efforts to seek finer-scaled mechanistic observations of relationships among individual organism behavior, resource use, and biological outcomes that improve our understanding of population-level resource ecology. Melding current techniques to obtain detailed evidence of how habitat is used at an individual level will allow us to relate resources to fitness for more efficiently understanding an animal’s ecology and improving conservation and control of populations. While we will continue to manage for populations, we must not lose sight of the individual variation that drives natural selection if we want to fully understand variation in resource-outcome relationships.
4

Temporal Variation in Space and Resource Use of Macaws in the Southeastern Peruvian Amazon

Adamek, Krista Anne 2011 May 1900 (has links)
Space use and resource use of three species of macaws (Ara ararauna, A. chloropterus, and A. macao) were studied for a period of three years in the southeastern Peruvian Amazon. Basic information on wild macaw populations is lacking due to the logistical and behavioral challenges of working with these species in dense rainforest. Population declines world-wide have been attributed significantly to a reduction in food and nesting resources due to habitat loss. This research aims to obtain baseline data on macaws in a region with relatively intact rainforest. Specific objectives were to (1) quantify space use, describe the spatial and temporal variation in movement patterns, explore habitat selection and spatial pattern of resources during the non-breeding season, and (2) identify key nesting and foraging species and determine whether there is seasonal variation in diet, and explore how resources may be related to movements and competition. Individuals from each species were radio-tagged and monitored from 2004 to 2008 by ground, platform, and aerial tracking. Seasonal ranges were estimated using MCP and KDE methods. Diversity and niche measurements and selection were calculated for dietary items, nesting substrate, and habitat. The relationship between palm habitat distribution and A. ararauna movements was explored using landscape analysis techniques. All species had similar home range sizes during the breeding season, ranging from a mean of 1,540 ha to 2,541 ha. Non-breeding ranges were significantly larger for A. ararauna (117,849 ha). Greater than 200 species of plants were consumed, yet seasonal preferences vary. The increase in dietary breadth and decrease in overlap during dry season is unlikely related to food scarcity or competition. Key nesting and dietary species include Mauritia flexuosa, Dipterix micrantha, and Bertholletia excelsa. Palm habitat is a key resource for Ara ararauna and associated with long-distance movements. This research addresses a critical gap in our knowledge regarding macaw movements and resource use in Amazonian rainforest. Despite their mobility, their low fecundity and specialized nesting requirements can impact reproductive success and population growth if habitat loss continues on its current trajectory.
5

Predator-prey dynamics among large carnivores and their ungulate prey: from the Great Lakes to the Last Frontier

Svoboda, Nathan James 13 August 2024 (has links) (PDF)
Identifying factors that influence spatial and temporal resource use is critical to understanding ecological relationships of sympatric species. Spatial and temporal shifts in resource availability, distribution, and vulnerability can influence animal space use, movements, foraging behavior, and prey selection. Identifying these factors is critical to understanding predator-prey dynamics. In Michigan’s Upper Peninsula, white-tailed deer (Odocoileus virginianus) exist in a multi-predator system that includes black bears (Ursus americanus), wolves (Canis lupus), coyotes (C. latrans), and bobcats (Lynx rufus). On Sitkalidak Island, Alaska, plains bison (Bison bison) were recently introduced into a single-predator island landscape that contains some of the largest brown bears (Ursus arctos middendorffi) in the world. The objectives of this research were to investigate how spatial and temporal shifts in resource availability, distribution, and vulnerability impact predator space use, movements, diel activity, and resource utilization, including how competition influences resource acquisition among sympatric carnivores. In Michigan, we investigated shifts in predator space use during three time periods based on white-tailed deer fawn availability and vulnerability including the pre-parturition (PPP, 1 May–24 May) limited mobility (LMP, 25 May–30 June) and social mobility (SMP, 1 July–31 August) periods and examined predator movements during LMP and SMP. In Alaska, we investigated resource use and diel activity patterns of Kodiak brown bears and plains bison during 2 time periods determined by temporal shifts in resource availability. Carnivore responses to fawn white-tailed deer distribution and vulnerability in Michigan varied among species but were congruent with life history strategies. Carnivores did not overall rely predominantly on fawns but shifted their space use and altered movements to maximize intake of seasonal resources. In Alaska, brown bears and bison did not exhibit high landscape attribute overlap during the early and late periods suggesting bears were not recognizing bison as a potential prey source. Although we observed some overlap in utilization of landscape attributes and diel activity between bears and bison, we suggest this overlap was a result of congruent resource requirements and overlapping spatial resource acquisition. This research provides additional insight into life history strategies among co-occurring species and dynamics of multi-species predator-prey systems.
6

Exploring the Ecological Footprint of Tourism in Ontario

Johnson, Peter January 2003 (has links)
Once considered a 'green' industry, tourism and its associated ecological impacts are now widely acknowledged. Focus within tourism planning has aimed to reduce the ecological burden placed on a destination area, and move towards a more sustainable tourism industry. This research proposes the use of the Ecological Footprint (EF) as a tool to compare the ecological costs of different types of tourism. The EF shows the relative amount of productive land appropriated by the activities and choices of an individual tourist. The main goal of this study was to analyse and compare the ecological resource use of tourism in Ontario. Surveys were conducted with tourists staying at 9 different types of accommodations throughout Ontario. Additional data were collected from personal interviews with accommodation managers at each location and incorporated into the EF calculation. Four areas of tourism ecological impact were identified; tourists' personal consumption, transportation, activity, and accommodation costs. These four components contributed in varying degrees to each tourist Ecological Footprint, and this variation became the main area of analysis. The findings of this research demonstrated that air travel contributes significantly to the total ecological cost of a particular tourism experience. Comparably, travel by personal car made a much smaller contribution to the tourist EF. Thus, local area tourists who could drive to a destination had a smaller EF than those long-distance domestic and international tourists who flew. Accommodation ecological costs were primarily a factor of the amount of built space available, and total energy usage per guest. Accommodations that had a large number of occupants for a given area and level of energy consumption achieved a scale of efficiency. In this manner, larger, more efficiently constructed accommodations often made smaller contributions to the tourist EF than small-scale, but inefficient accommodations. The main conclusion was that the ecological impacts of tourism can be quantitatively recorded, and that a complete trip view of tourism ecological resource use is necessary. When considering practical applications in the tourism industry, an Ecological Footprint analysis could be used by tourism managers as an evaluative tool to compare the ecological outcome of various construction, programming, and operational changes. For the tourist, the EF can serve as an 'eco-label', to distinguish one type of 'green' tourism from another, creating a more informed consumer. Ultimately, the Ecological Footprint serves one purpose- to demonstrate that less ecologically consumptive tourism choices are possible for both tourists and tourism managers.
7

Exploring the Ecological Footprint of Tourism in Ontario

Johnson, Peter January 2003 (has links)
Once considered a 'green' industry, tourism and its associated ecological impacts are now widely acknowledged. Focus within tourism planning has aimed to reduce the ecological burden placed on a destination area, and move towards a more sustainable tourism industry. This research proposes the use of the Ecological Footprint (EF) as a tool to compare the ecological costs of different types of tourism. The EF shows the relative amount of productive land appropriated by the activities and choices of an individual tourist. The main goal of this study was to analyse and compare the ecological resource use of tourism in Ontario. Surveys were conducted with tourists staying at 9 different types of accommodations throughout Ontario. Additional data were collected from personal interviews with accommodation managers at each location and incorporated into the EF calculation. Four areas of tourism ecological impact were identified; tourists' personal consumption, transportation, activity, and accommodation costs. These four components contributed in varying degrees to each tourist Ecological Footprint, and this variation became the main area of analysis. The findings of this research demonstrated that air travel contributes significantly to the total ecological cost of a particular tourism experience. Comparably, travel by personal car made a much smaller contribution to the tourist EF. Thus, local area tourists who could drive to a destination had a smaller EF than those long-distance domestic and international tourists who flew. Accommodation ecological costs were primarily a factor of the amount of built space available, and total energy usage per guest. Accommodations that had a large number of occupants for a given area and level of energy consumption achieved a scale of efficiency. In this manner, larger, more efficiently constructed accommodations often made smaller contributions to the tourist EF than small-scale, but inefficient accommodations. The main conclusion was that the ecological impacts of tourism can be quantitatively recorded, and that a complete trip view of tourism ecological resource use is necessary. When considering practical applications in the tourism industry, an Ecological Footprint analysis could be used by tourism managers as an evaluative tool to compare the ecological outcome of various construction, programming, and operational changes. For the tourist, the EF can serve as an 'eco-label', to distinguish one type of 'green' tourism from another, creating a more informed consumer. Ultimately, the Ecological Footprint serves one purpose- to demonstrate that less ecologically consumptive tourism choices are possible for both tourists and tourism managers.
8

Sustainable development: a case study of the natural resource use of Yelwa Village, Nigeria

Korndoerfer, Tammy Linda January 2009 (has links)
The world today faces many challenges. Reducing poverty and protecting the environment are prominent amongst these challenges, and consequently both are high on priority lists for many national, international, governmental and non-governmental organizations. Since the 1980s there has been an increasing awareness that environmental protection must not fly in the face of social justice, especially in developing countries, and that a system can only truly achieve sustainability if it is socially just and economically sound, as well as environmentally secure. Likewise poverty reduction at the cost of the environment is worthless in the long term. This has given rise to much more holistic approaches to both conservation and poverty reduction policies and brought the rights of communities living in or near protected areas into the international focus. However, wether it is possible to conserve biodiversity and protect habitats successfully without undermining the livelihoods of local communities, or wether it is possible to offer development aid to an impoverished region without jeopardizing their local environment, is a question which has not been resolved. This study approaches this debate by examining the relationship between the livelihoods and natural resources of a rural village adjacent to a forest reserve on the Mambilla Highlands in Nigeria. A mixture of qualitative and quantitative techniques were employed during five months spent living on location to develop a picture of the situation as it currently exists, the environmental effects of development in the village to date, and the effects of these environmental changes on people’s livelihoods. Based on this research this thesis concludes that development in a region certainly increases the vulnerability of the environment. However, rather than concluding that this makes development and environmental protection conflicting agendas, this thesis argues that this period of vulnerability presents opportunities to develop true sustainability, as effective sustainable practices can develop from the experience of resource depletion. Additionally, examples of how knowledge sharing and dialogue between western scientists and indigenous communities has the potential to facilitate and accelerate this process are discussed.
9

Sustainable Development: A case study of the natural resource use of Yelwa Village, Nigeria

Korndoerfer, Tammy Linda January 2009 (has links)
The world today faces many challenges. Reducing poverty and protecting the environment are prominent amongst these challenges, and consequently both are high on priority lists for many national, international, governmental and non-governmental organizations. Since the 1980s there has been an increasing awareness that environmental protection must not fly in the face of social justice, especially in developing countries, and that a system can only truly achieve sustainability if it is socially just and economically sound, as well as environmentally secure. Likewise poverty reduction at the cost of the environment is worthless in the long term. This has given rise to much more holistic approaches to both conservation and poverty reduction policies and brought the rights of communities living in or near protected areas into the international focus. However, wether it is possible to conserve biodiversity and protect habitats successfully without undermining the livelihoods of local communities, or wether it is possible to offer development aid to an impoverished region without jeopardizing their local environment, is a question which has not been resolved. This study approaches this debate by examining the relationship between the livelihoods and natural resources of a rural village adjacent to a forest reserve on the Mambilla Highlands in Nigeria. A mixture of qualitative and quantitative techniques were employed during five months spent living on location to develop a picture of the situation as it currently exists, the environmental effects of development in the village to date, and the effects of these environmental changes on people’s livelihoods. Based on this research this thesis concludes that development in a region certainly increases the vulnerability of the environment. However, rather than concluding that this makes development and environmental protection conflicting agendas, this thesis argues that this period of vulnerability presents opportunities to develop true sustainability, as effective sustainable practices can develop from the experience of resource depletion. Additionally, examples of how knowledge sharing and dialogue between western scientists and indigenous communities has the potential to facilitate and accelerate this process are discussed.
10

Essays in rural energy, forest dependency and covariates of fuel saving technologies in Ethiopia

Beyene, Abebe Damte 08 May 2012 (has links)
This thesis contains empirical findings on rural energy, forest resource use and fuel saving technologies in Ethiopia. Using a household survey data conducted in different parts of the country, efforts were made to contribute to the limited empirical evidences in Africa in general and Ethiopia in particular. The thesis has four empirical chapters and the first and the last chapters of the thesis are the introduction and summary, respectively. The main findings and policy implications are highlighted below. The second chapter examines the coping mechanisms of rural households to fuel wood scarcity. Using randomly selected households, the results of the empirical analysis show that rural households residing in forest degraded areas respond to fuel wood shortages by increasing their labor input to fuel wood collection. The study also finds that there is no evidence for the substitution between fuel wood and dung or fuel wood and crop residues. Supply side strategies alone may not be effective in addressing the problem of forest degradation and biodiversity losses. Any policy on natural resource management in general and rural energy problems in particular should make a distinction between regions of different forest degradation level. The third chapter examines the relationship between property rights and household demand for fuel wood, as measured by the source from which fuel wood is collected. Results from the discrete choice model indicate that active local-level institutions reduce the dependency on community forests, but, otherwise, increase household dependency on open access forests. However, land tenure security and local level institutions do not increase demand for fuel wood collected from private forests. The results suggest that there is a need to bring more open access forests under the management of the community and increase the quality of community forestry management in order to realize improvements in forest conservation. The fourth chapter of this thesis deals with finding empirical evidence on the role of local level institutions and property right regimes on forest dependency using data from a random sample of rural households in Ethiopia. We find that forest dependency is negatively correlated to the wealth status of the household. Our estimation results suggest that local level institutions are not significant factors in determining use of non wood forest products unlike major forest products such as timber or woody materials in general. We also find that there is a need to expand the current practice of participatory forest management to other open access forest areas. We conclude that generalization on the forest-poverty link depends on the type of forest management and the specific characteristics that prevail in the area. The last chapter of the thesis deals with finding empirical evidence on the determinants of adoption of different types of fuel saving technologies in urban Ethiopia. The duration analysis suggests that adoption rates have been increasing over time, that income and wealth are important contributors to adoption, and that substitute technologies tend to hinder adoption of Lakech charcoal stove. However, it was not possible to consider prices or perceptions related to either the technologies or biomass availability in the duration models, and, therefore, further research is needed in order to further inform policy with respect to household technology adoption decisions. / Thesis (PhD)--University of Pretoria, 2012. / Economics / unrestricted

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