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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.
121

None

Lo, Wen-Cheng 25 July 2001 (has links)
Ecologist Tom Dale and Vernon Gill Carter Published a book ¡mTopsoil and Civilization¡n in 1955, There is a paragraph in the prolog¡G ¡uCivilized human always can temporarily control the environment mostly. Their main problem caused of the misconceiving that the temporary control can be forever. They misconceive that they are the ¡§dominator of the world¡¨, but don¡¦t realize the rule of the nature at all. Human no matter civilized or not, nevertheless, is the son not the master of nature. If they want to sustain and maintain the ecological environment, their behavior must follow the rule of nature. If they try to evade these rules, the consequence usually ruins the surrounding environment what nurture them. When the environment gets worst rapidly, their civilization declines too.¡v It seems to be a fate, like Morrie said in ¡mTuesday with Morrie¡n¡G¡uEvery one knows he will die, but nobody takes it as real.¡vHuman does not only treat his own life like this way, but also the environment what they survive and live in! From 1992, ¡¦Rome Club¡¦ published the book ¡mThe limit of growth¡n, the consciousness of environmental protection started to head up. Some issues like Ecology of commerce, Sustainable development, Land ethics, Deep ecology and Environmental economic came out one after one. Purely economic and efficient considering of design and production can¡¦t satisfy these kinds of demand. For this sake, International Standard Organization issued out the ISO-14000 series and accepted worldwide gradually. ISO-14040¡GLife Cycle Assessment¡Aevaluating the impact to the environment from material input, manufacturing, transportation, using, recycle, disposal, by other words--- ¡¥from the cradle to grave¡¦. LCA try to use quantitative concept to interpret the environmental impact or damage from human made product. It may provide environmental protection user a systematic thinking to distinguish which product is environmental amity product, which is not; also could be a stand for environment strategy. Applied on the production, it can be a good tool for ¡¥Green Design¡¦ thinking, to reduce the impact to the environment from every stage in production. This thesis is going to study the 6V4Ah Lead acid battery that used widely in the market. Quoting LCA¡¦s indications and SimaPro 4.0 software developed by Pre Consultants B.V. as the database and tools to evaluate the impact and damage to our environment. About the basic data bank, we adopt the local databank built by ITRI (Industrial Technology Research Institute) for years and the data included in SimaPro software. Those are Pre4, PreNL, BUWAL250 and IDEMAT96. Following the analysis procedures as Classification, Normalization, Evaluation by both impact orientation method --- Eco-indicator 95 method and damage orientation method --- Eco-indicator 99 method to evaluate this product¡¦s LCA study. Further more, look forward to provide a potential evaluation way to evaluate and compare to other various batteries.
122

Cumulative effects analysis in U.S. Forest Service decision-making

Schultz, Courtney Allison. January 2009 (has links)
Thesis (PHD)--University of Montana, 2009. / Contents viewed on November 25, 2009. Title from author supplied metadata. Includes bibliographical references.
123

Plants in the garden an approach to modeling the impact of industrial activities in ecosystems /

Reap, John J. January 2004 (has links) (PDF)
Thesis (M.S.)--Mechanical Engineering, Georgia Institute of Technology, 2004. / Matthew J. Realff, Committee Member ; Farrokh Mistree, Committee Member ; Berdinus A. Bras, Committee Chair. Includes bibliographical references (leaves 191-195).
124

The Effect of a tax on coal in South Africa a CGE analysis /

De Wet, Theunis Jacobus. January 2003 (has links)
Thesis (Ph. D. (Economics))--University of Pretoria, 2003. / Includes bibliographical references (leaves 174-181).
125

Swedish hydropower : A literature study about Swedish hydropower, environmental impact and EU: s Water Framework Directive

Karlberg, Anna January 2015 (has links)
In Sweden, EU: s Water Framework Directive led to an investigation that started in April 2012 by the Swedish government, called Vattenverksamhetsutredningen freely translated to "Water Activities Survey", with the purpose to investigate the Environmental Code’s rules concerning water activities and water plants. The survey is divided into 3 reports, two sub-reports and a final report. One of the sub-report is focused on Swedish hydropower and the investigators found that many hydropower plants have old permits. One suggestion in the survey was to reconsider old permits so they would become consistence with today’s Environmental Code. There have been discussions regarding whether Sweden will lose much of its electricity production from hydropower as an outcome if the survey’s suggestions becomes reality. The aim with this literature study is to investigate how the EU: s Water Framework Directive and the Water Activities Survey will affect Swedish hydropower and if there will be a decrease in electricity production as an outcome if the suggestions made in the survey becomes reality. The results in this literature study shows that there will probably be a decrease in production for Swedish hydropower, but with how much is hard to say because the Swedish government has not yet decided what they will do with the suggested actions in the Water Activities Survey. A comparison is done with Sweden’s import and export statistics between the years 2001-2014 with a predicted loss of 13 TWh per year, which is a number taken from a survey made by Vattenfall. A comparison with a loss of half of 13 TWh per year is also done. Between the years 2001 and 2014 Sweden imported electricity 6 out of 14 years and exported electricity 8 out of 14 years. If adding the predicted loss of 13 TWh per year to the import and export statistics, Sweden would have had to import electricity 12 years and export 2 years. If adding a loss of 6.5 TWh per year Sweden would have had to import electricity 8 years and export 6 years. The conclusions is that Sweden will have to import a lot more electricity if only looking at import and export statistic if the loss of electricity is between 6.5-13 TWh per year.
126

Impact assessment of non-native parasites in freshwater fisheries in England and Wales

Williams, Chris F. January 2007 (has links)
Non-native parasites pose a significant threat to aquatic bio-diversity and fishery development. Many factors have facilitated the introduction of non-native parasites into England and Wales. Identifying the effects of these parasites and the importance of any changes to wild fish populations represents a considerable challenge. However, in order for the Environment Agency to identify future disease threats, effectively manage resources and implement practical and sustainable control measures, the risks posed by these parasites to fisheries must be better understood. A structured, risk-assessment process for non-native freshwater parasites is proposed. This approach includes procedures for hazard identification, impact assessment, risk management and communication. A quantitative approach to hazard identification provides an initial prediction of impact at the time of introduction to inform decisionmaking and guide preliminary control measures. This is followed by a more comprehensive framework for impact assessment that promotes understanding of changes at host, population and fishery levels. These are placed into context with the economic and ecological value of native resources. An independent 'non-native parasite review group' has been convened to ensure consistency of policy decisions and clear communication of disease risks to interested bodies. It is hoped that this wil assist the management of future invasions and provide a scientifically robust foundation on which to base proportionate control measures. The Category 2 parasites are defined as "species having a significant disease potential when introduced into waters where they do not already exist, or are non-indigenous species with unknown pathogenicity and distribution". Understanding of the dangers posed by these parasites varies considerably. Ergasilus sieboldi, Anguilicola crassus, Bothriocephalus acheilognathi and Lernaea cyprinacea, are well recognised non-native fish pathogens that pose a considerable threat to fisheries. Conversely, the effects of other introduced parasites remain poorly understood. In many cases, a paucity of published literature at the time of introduction has limited a reliable assessment of impact. Four non-native parasites were considered a priority for further study. These were Paraergasilus longidigitus (Copepoda: Poecilostomatoida), Ergasilus briani (Copepoda: Caryophylldae) Poecilostomatoida ), Atractolytocestus huronensis (Cestoda: and Philometroides sanguinea (Nematoda: Philometridae). Pathological, epidemiological and experimental investigations were undertaken to assess the effects of these parasites at host and population levels. P. longidigitus can cause pronounced pathological changes to the olfactory epithelium of infected fish. Although this damage provides the potential for disruption to spawning through reduced sensitivity to reproductive chemical cues, experimental observations combined with seasonality studies suggest that the parasite is unlikely to disrupt reproduction within infected cyprinid fisheries. Similarly, studies conducted on the caryophylidean cestode A. huronensis provide little evidence to suggest that the parasites poses a threat to car fisheries. Damage within the intesinal tract was characterised by relatively mild mechanical and inflammatory changes. Infections of up 213 parasites had no adverse affect upon the conditon of common carp. Based on these findings and the application of the aformentioned risk model, P. longidigitus and A. huronensis are considered to be of low disease risk to fisheries. The pathology of E. briani and P. sanguinea are described for the first time. Literature suggests that both parasites are pathogenic to juvenile fIsh. E. briani causes a number of pathological changes within the gils of juvenile cyprinids, although these remain localised due to the very strict site specificity of the parasite. Migrations of the nematode P. sanguinea causes damage to the fins and caudal musculature of juvenile crucian car. For both parasites, the extent and severity of pathological changes are inversely proprtional to host size. Further studies at the population level are needed before an assessment of impact to fisheries can be made. The difficulties associated with studying the effects of introduced parasites to juvenile fish populations in the wild are recognised. Recommendations for further study are given.
127

Pah hu wichi (From Big Spring Running Down): Big Spring Ethnographic Assessment US 95 Corridor Study

Stoffle, Richard W., Pittaluga, Fabio, Earnest, Tray G., Eisenberg, Amy, Amato, John, Dewey-Hefley Genevieve 09 1900 (has links)
It was determined in the mid- 1990s that Highway 95 in southern Nevada had experienced a tremendous increase in traffic and increased safety hazards for motorists due to growth in population and commerce in the Southwest. Federal, state, and local governments worked to find a solution to the impacts of increased traffic and have chosen a number of alternatives related to highway expansion. This is an American Indian ethnographic study for the Big Springs Highway 95 Corridor Project. The study area included the Big Spring Complex and associated American Indian sites potentially impacted by the westward expansion of U.S. 95 north of its junction with U.S. 15. The study does not include an analysis of U.S. 95 impacts to the east of the Big Springs complex towards what is known as Lorenzi Park. This report is based on interviews with American Indian representatives from six Southern Paiute tribes and the Las Vegas Indian Center. Each tribe and organization chose to send one or more tribal members to evaluate the potential impacts to American Indian cultural resources that would occur if Highway 95 were to be expanded to incorporate a portion of the current Big Spring location. This report provides the Southern Paiute evaluations of the proposed expansion.
128

Norse landnám and its impact on the vegetation of Vatnahverfi, Eastern Settlement, Greenland

Ledger, Paul M. January 2013 (has links)
No description available.
129

An analysis of the environmental impact statement of the Warm Springs Dam Project

Curtis, Cassie Susan, 1951- January 1976 (has links)
No description available.
130

An Interdisciplinary Study on Farm Based Biogas Production in Southern Brazil

Hjort, Anders, Norin, Simon January 2008 (has links)
Today the use of anaerobic digestion technique emerges as an alternative to the conventional treatment method of pig slurry to the pig producers in Brazil because of the energy demanding intensive pig production and the negative environmental impact that arises during storage and use. The end products of AD technique are biogas as an energy source and digestate that can be used as a fertilizer. The study took place at two pig producers in southern Brazil in order to evaluate the biogas production in the area, its applications and environmental impact. The visited pig producers run a confined animal production system where the slurry that is used in the anaerobic digesters is diluted. The studied digesters are covered with an air tight flexible plastic membrane that takes the shape of a balloon where each digester has the volume of 620 m3. Sedimentation occurs inside each reactor where the temperature also fluctuates. The produced biogas is conveyed to a torch where the biogas is combusted. The results of this study show that the digesters are working properly but there is a need for mixing and constant temperature in order to optimize the process. Biogas is primarily suited for heat production and the digestate can be used as a fertilizer. Biogas production is considered to have a positive environmental impact if the biogas is used or combusted in a torch. There is also a need to apply a cover over the digestate during the storage time to avoid ammonia emissions. The approximated biogas potential for Rio Grande do Sul is nearly 100 GWh/year. For an approximated biogas potential of more consideration it is found that further studies of the housing systems in Rio Grande do Sul are needed. This is due to a greatly varying amount of degradable materials in the pig slurry from one ranch to another.

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