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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

Water Discharge Models, Seasonal Effluent Mass Loading, and Best Management Practices for Crawfish Ponds

Parr, Landon David 20 November 2002 (has links)
Nearly 35,000 ha are used to grow crawfish in southwest and south-central Louisiana, and many of these ponds discharge into impaired water bodies. In 2002, proposed guidelines were published by the United States Environmental Protection Agency (USEPA) assigning effluent limitations and standards for some aquaculture production systems and exempting others (e.g. crawfish ponds). This research had three objectives relative to crawfish ponds: develop water discharge models; final drawdown effluent quality and seasonal mass loading of solids and nutrients; and identification of Best Management Practices (BMPs) that could reduce effluent discharge and improve effluent quality. Models for south-central and southwest Louisiana with a 15 cm storage capacity showed that excess precipitation overflow (final drawdown not included) can be decreased by 28% for a high precipitation year, 61% for an average precipitation year, and 100% for a low precipitation year. The major sources of effluent from crawfish ponds are (1) overflow during winter when precipitation exceeds evaporation, evapotranspiration, and infiltration and (2) discharge during the summer drawdown period. Pond evaporation and evapotranspiration combined are the greatest sources of water loss (68%) during a crawfish production cycle. During final drawdown, solids were high during the first 5% of pond water discharge due to poorly consolidated sediment in and around the drain and high during the last 20% of pond water discharge due to the poorly consolidated pond bottom sediments. During final drawdown: total suspended solids were reduced over a distance of 268 m by 28% at the Aquaculture Research Station (wide, shallow, non-vegetated ditch); total suspended solids increased over a distance of 268 m by 15% at the Rice Research Station (narrow, non-vegetated ditch); and total suspended solids were reduced over a distance of 268 m by 80% at the University of Louisiana at Lafayette Model Sustainable Agricultural Complex (deep vegetated ditch). To reduce solid and nutrient mass loading in crawfish pond discharge, ponds should be slowly drained from the top of the water column and avoid draining the last 20% of the pond volume. If that is not possible, then it is recommended to treat the last 20% of the pond volume by sending the discharge through deep vegetated ditches, settling basins, or constructed wetlands with a residence time of 4 d to 14 d.
2

Economic growth with a renewable resource sector /

Elíasson, Lúðvík. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (p. 148-150).
3

Evaluation of the topologic instantaneous unit hydrography on rural watersheds in Southeast Arizona

Lantz, Douglas Gregory, January 1998 (has links) (PDF)
Thesis (Ph.D. - Renewable Natural Resources)--University of Arizona. / Includes bibliographical references (leaves 200-203).
4

A Framework for Evaluating and Assessing the Effects of Urban Growth on Protected Areas

Yeasmin, Dilruba January 2011 (has links)
Protecting and managing National Parks and Monuments effectively is very important for their future sustainability. Urban encroachment on areas adjacent to protected areas is often considered a potential threat to the natural resources inside the protected areas. To minimize these threats, evaluating and assessing the effects of urban encroachment on protected areas and developing effective management strategies is critical. To implement any management strategy, interactions, support and perceptions of changing conditions from neighboring communities is imperative. The goal of this study was to develop a framework to assess perception of land use change along the borders surrounding Saguaro National Park East. The objectives of this study were to determine 1) the change in landscape that has occurred as a result of urban encroachment in and adjacent areas to Saguaro National Park (SNP) over a 15 year period 2) the degree to which neighbors surrounding SNP perceive that these changes have occurred due to urban encroachment 3) the perception of neighbors surrounding SNP that increased urbanization has led to more impacts on local wildlife 4) the possible planning and management strategies that neighbors agree would lead to reduce impacts of urban encroachment on protected areas and how strongly do they support the implementation of these proposed planning and management strategies. Results of this study indicated that landuse / landcover changes have occurred over the landscape at a rapid rate and in large areas within one mile of lands adjacent to the boundary of SNP East. Urban area increased 2.45%, agricultural lands decreased 76.15% and forested lands decreased 6.19% from its previous class in one mile adjacent land to the park from 1992 - 2001. Building units (residential) increased dramatically by 71.53% in this one mile buffer in the period between 1992 and 2007. In addition, respondents that live in adjacent lands perceive these changes over the landscape due to urban encroachment at a moderate degree strongly agree that increased urbanization has led to more negative impacts on local wildlife. Further, respondents strongly support more communication between authorities, developers and neighbors and environmental education programs with regards to urban encroachment on SNP.
5

Examining potential effects of marine renewable energy developments on top predators

Philpott, Evelyn January 2013 (has links)
This thesis uses data collected over three summers in 2010, 2011 and 2012 at the Isle of May National Nature Reserve, Scotland to examine top predator presence and behaviour in a moderately fast tidal stream site. Fieldwork consisted of an intensive land based observation survey of seabirds at sea, acoustic monitoring of small cetaceans and the deployment of a suite of oceanographical tools to simultaneously collect data on a fine temporal scale over a study area of ~1.5km2. The aim of the study was to examine the potential effects of marine renewable energy developments on top predator behaviour in a tidal stream site by addressing some of the key data gaps such as habitat use in tidal stream areas, dive behaviour and collision and disturbance risk assessment. Acoustic detections of harbour porpoises were investigated as a function of physical environmental variables. Strong links between porpoise presence and increased thermal stratification and chlorophyll levels were detected along with a very strong diurnal pattern with increased detections at night. There was no relationship with tidal state. The habitat use of five species of breeding birds at sea adjacent to breeding cliffs was examined to gauge what environmental factors drive habitat use at these sites. Counts of foraging kittiwakes were examined in relation to environmental variables and while strong temporal trends emerged there was no link with oceanographic features. The study site was predominately used for loafing (non foraging behaviour) and so species specific temporal variation in loafing behaviour was analysed. Strong seasonal and diurnal trends in loafing emerged for all species which could be linked to differences in their breeding phenology. These results can be used in assessing and mitigating disturbance to these birds from marine renewables developments. Age specific variation in dive behaviour in the European shag was examined to determine whether newly fledged juveniles were at a greater risk of collision with tidal turbines than adults. Juveniles initially demonstrated a shorter dive duration than adults but after 4-6 weeks their dive duration had significantly increased. However age specific difference in dive behaviour in relation to water depth iii remained unchanged over time with juveniles showing no relationship between dive duration and water depth while adults increased dive duration in deeper water. The implications of this result for assessing age specific collision risk for this species is discussed. Results from this study were used to populate a framework for assessing collision and disturbance risk to seabirds in the near shore area adjacent to the breeding colony from a small scale tidal turbine development scenario. A method was developed to quantify risk by combining relative abundance data, behavioural data and published data on activity budgets for four species; guillemots, razorbills, puffins and shags. The output from this thesis has practical applications for informing the temporal and spatial scale of data collection and survey design in environmental impact assessments regarding marine renewable energy developments with emphasis on understanding the mechanistic links driving predator behaviour. Results can also be used to design appropriate mitigation procedures to prevent disturbance to loafing or foraging birds.
6

Inheritance, obligation, and responsibility in a commons dilemma /

Porter, Michael K. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 29-34). Also available via Humboldt Digital Scholar.
7

Effect of oil prices on returns to alternative energy investments

Schmitz, Anthony. January 2009 (has links)
Thesis (M. S.)--Economics, Georgia Institute of Technology, 2010. / Committee Chair: Vivek Ghosal; Committee Member: Byung-Cheol Kim; Committee Member: Chun-Yu Ho; Committee Member: Tibor Besedes. Part of the SMARTech Electronic Thesis and Dissertation Collection.
8

Dwelling well an application of Christopher Alexander's theory of wholeness to investigate occupant affective responses to homes incorporating renewable natural resources /

Peacock, Cherie Lynette, January 2005 (has links) (PDF)
Thesis (M.S. in architecture)--Washington State University, December 2005. / Includes bibliographical references (p. 102-106).
9

Benefication of glycerol from algae and vegetable oil

Mafu, Lubabalo Rowan January 2011 (has links)
This research has been directed at furthering the utilization of crude glycerol oversupply formed as a by-product from the biodiesel manufacturing process. Phosphorylation of hydroxyl groups is a synthetic route that was investigated for the conversion of glycerol into a glycerol-phosphate (GPE) ester mixture. The process investigated for the synthesis of a GPE product was based on phosphorylation reaction procedures that were previously reported in the literature. The reaction to convert glycerol into a GPE mixture has been thoroughly investigated and the hydrogen chloride gas formed as a reaction by-product has been optimized. The chemical properties of GPE have been studied and discussed together with a mass balance of the overall glycerol phosphorylation process. The phosphate groups contained in polyhydric phosphate molecules have a potential chelating effect on cations. There are several cations that may be chelated by the phosphate ester group of polyhydric phosphate molecules. These cations include ammonium (NH4+), Potassium (K+), Calcium (Ca2+) etc, which are essential as nutrients in plant fertilizer formulations. This research has investigated the use of a GPE synthesized from glycerol in the laboratory and the use thereof as a phosphorus containing base in the formulation and evaluation of Nitrogen, Phosphorus and Potassium (NPK) containing fertilizer solution, Ammonium-Potassium-Glycerol-Phosphate (APGP) fertilizer solution. The APGP fertilizer solution has further been evaluated by growing two week old tomato seedlings under controlled conditions. The performance of the APGP fertiliser solution has been evaluated using design of experiments by comparison with traditionally used liquidAmmonium-Potassium-Phosphate inorganic fertilizer. This fertilizer solution has been prepared in similar manner as APGP formulation with the difference between them being the source of phosphorus. The results have been evaluated using statistic analysis where a significant difference between the evaluated fertilizer formulations was found. The comparative study of these formulations was monitored by the observed plant weights. A blank treatment was used as a control to determine if a significant difference among these formulations was observed. Anova single factor and t-Test methods (Two-Samples assumed of equal variances) are statistical models that were applied to interpret the observed experimental data with respect to wet and dry weighed masses of tomato seedlings. These methods indicated a confirmed conclusion that there was a significant difference between APPO4 solution and APGP solution. The observed data have shown that the APPO4 solution provided significantly better fertigation performance than APGP solution. Consequently, further investigation has been conducted to determine the cause of the poorer performance of the APGP solution. The further study of the APGP fertilizer solution included nutrient stability testing, biological analysis and other observed physical changes of the APGP solution over time. Biological results have revealed the presence of a Fusarium fungus species that has grown and is suspended in APGP fertilizer solution. This microbe species has been observed to play a vital role in consuming fertilizer nutrients. In addition, the observed abnormal plant growth and nutrient decomposition of the APGP formulation has been proposed to be mostly a result of the pathogenicity of the fusarium fungi species that was suspended in the APGP solution. Further work has been proposed in which the effect of such biological contamination is eliminated through adequate sterilization procedures and the APGP formulation re-evaluated.
10

Philosophical foundations and conceptual bases of administrative procedures of multiple use management of natural resources

Smith, David Anthony January 1970 (has links)
In attempting to determine the background to the controversial term "multiple use," it was deemed necessary to briefly examine preceding social behaviour and legislation. A brief study of early European agricultural practices, through to the Industrial Revolution, allows an insight into the rural background of the early immigrants to North America. The Conservation Movement of the early 1900s was a result of socially unacceptable exploitation of natural resources and dissatisfaction with the American governments' methods of land disposal in the name of "progress." The rapid demise of the Movement is attributed to its failure to produce practical guidelines for resource management. Subsequent resource development in North America has been fragmentary; a major cause of inefficiency and a disregard for social implications. The definition of "multiple use" that appeared in the 1960 Act, like the principles of the Conservation Movement, relied on platitudes rather than practicalities. The goals of multiple use are examined, and a new definition is proposed, as is the substitution of "integrated resource management" for the shibboleth of "multiple use." The history of the development of Canada's resources parallels that of the United States. Yet because of the smallness of the population in relation to the size of the country, the exhaustibility of natural resources has been barely contemplated. Serious public concern for the manner in which Canadian resources are being managed is only of recent occurrence. The responsibility for integrated resource management lies with provincial governments. Except for the United States Forest Service, the case studies conclusively show that the biggest obstacles to the implementation of integrated resource management, are of a political nature. Some techniques of economics that pertain to the allocation and distribution of wealth generated by natural resources are examined. While none of these are entirely satisfactory, Benefit-Cost Analysis is proposed as a possible first step toward better control of resource development. In including man and his social structures within its deliberations, the discipline of ecology gains sounder foundations for analyzing the effects of resource management on society. The application of systems analysis to such complex ecological problems has great potential in allowing management strategies to be explored before being implemented. A hypothetical model is developed in which systems analysis is used to effect integrated resource management. Such a form of management presently remains as an ideal because of existing governmental, and industrial relations. Since voluntary cooperation for the public welfare appears unlikely in the near future, research will be needed to determine at which level of government to establish a department, whose function will be that of integrating resource management. / Forestry, Faculty of / Graduate

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