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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.
101

The Effects of Land-Use Change on the Hydrological Properties of Andisols in the Ecuadorian Paramo

Hartsig, James Joseph 01 May 2011 (has links)
The Ecuadorian páramo is characterized by unique soil properties that allow the ground to hold large amounts of water. These páramo grasslands support Andean cities and communities as a source of water for municipal, industrial, and agricultural use. Although recent research has suggested that changes in land use can decrease the amount of water and affect the water-holding capabilities of the soil, the hydrologic effects of different land uses, including burning for livestock grazing and pine planting for carbon credits, are currently under debate. This research tested hypotheses about moisture-related properties of páramo soils under different land uses at two study areas in Ecuador. Bulk density, volumetric water content, water retention, and general physical properties were identified and compared between sites at those study areas. Soil structure differed between pine sites and other sites at both study areas, and moisture consistency differed between pine and other sites at the Mazar Wildlife Reserve. Volumetric water content values were high (mean of 86% at one Mazar site) but the pine sites contained less water by volume than the other sites. Water retention data showed that the surface horizons of all sites at both study areas require more pressure to release moisture than the subsurface horizons. Compared to other sites studied, the pine sites from both study areas have lower gravimetric water contents at saturation through -6.0 kPa. Different burning regimes do not appear to affect soil properties, in-situ moisture content, or water-retention capacity. The introduction of pine plantations in the páramo at both study areas appears to have lowered soil moisture contents and reduced bulk density in the soil profile. This research adds to a growing group of studies that show that changes in land management can affect the hydrological properties of soils.
102

National Park Service Cave and Karst Resources Management Case Study: Great Smoky Mountains National Park

Nolfi, Daniel C. 01 May 2011 (has links)
As discussed in the National Parks Service’s (NPS) Directors Orders/Natural Resources Management Reference Manual #77 and the 2006 NPS Management Policy Handbook, implementing a management plan specifically for cave and karst resources within a national park is paramount to afford these resources appropriate protection. With support from the Federal Cave Resources Protection Act and the National Park Service Organic Act of 1906, management actions protecting caves has begun to place significant importance outside the traditional cave environment onto a broader karst landscape. The need to understand and protect the karst environment and caves as a karst resource has taken a much larger role in the scientific literature and has increased interest in its federal management application. Proactive management through the use of holistic karst wide management plans and programs is shown to provide superior measures for resource protection when compared to the shortcomings associated with reactive cave focused management. The use of Great Smoky Mountains National Park (GRSM) as a case study supports the need to develop and implement a proactive cave and karst management plan specific to their resources. Management decisions with regards to cave and karst resources currently follow the park's general directives and Superintendent's Compendium. GRSM’s caves and karst areas represent unique resources, such as extensive vertical relief and rare biota, requiring special management in order to effectively protect them and to manage those who study and recreate within them. Characteristics such as these necessitate holistically addressing management of these resources.
103

Determining the lon-exchange Mechanism of Strontium into a Niobium Doped Titanosilicate

Kramer, Samantha Jane 01 May 2011 (has links)
A 25% niobium substituted sitinakite was exchanged with strontium as time resolved X-ray diffraction data was collected. The structural modeling of this data by Rietveld method1 has lead to the determination of the atomic positions of the ions and unit cell parameters as strontium occupancy increases. The starting material of the exchange experiment is the protonated phase, H2Nb0.67Ti1.33SiO7·1.9 H2O, with space group P42/mcm2,3. Once strontium (Sr2+) enters the unit cell, extra-framework H2O molecules shift to provide the necessary hydration coordination. These new positions of H2O result in a lowering of symmetry to the P-42m space group, and it is thought that the new hydrogen bonding network serves to enhance strontium ion diffusion into the channels of sitinakite. Exchange of strontium into the microporous material reaches a maximum fractional occupancy of 21% when a 10.0 mM strontium ion solution is forced over the powdered material. Sequestration of strontium into this material has contributed valuable information to the study of microporous materials and ion exchange chemistries.
104

Multiple Storm Event Impacts on Epikarst Storage and Transport of Organic Soil Amendments in South-Central Kentucky

Vanderhoff, Sean M. 01 December 2011 (has links)
The groundwater in agricultural karst areas is susceptible to contamination from organic soil amendments and pesticides. During major storm events during 2011, dye traces were initiated using sulphorhodamine-B, fluorescein and eosine in a groundwater recharge area where manure was applied to the ground. Fecal coliform samples were collected from significant storm events from January-September 2011. Water samples and geochemical data were collected every four hours before, during, and between the storm events from a waterfall in Crumps cave flowing from the known recharge area to track the transport and residence time of the epikarst water and organic soil amendments during variable flow conditions. Two dataloggers at the same waterfall were set up to collect 10-minute data, which included pH, specific conductivity, temperature, and discharge. Total rainfall amount and other surface meteorological data were collected from a rain station located above the cave. Cave water samples were collected for the analysis of anions, cations, bacterial count, and the presence of dye. The dye traces show variability in the characteristics of epikarstic response and flowpaths. The changes in geochemistry indicate simultaneous storage and transport of meteoric water through epikarst pathways into the cave, with rapid transport of bacteria occurring through the conduits that bypass storage. Fecal coliform counts were elevated all through the study period indicating survivability in soils through the seasons. The results indicate that significant precipitation events affect the storage properties and rapidly impact the various pathways and timing of contaminant transport through the epikarst zone, eventually allowing these contaminants to be transported unfiltered in to the groundwater supply. This study shows that current best management practices in karst lands need to be revisited to incorporate areas that do not have surface runoff but where contaminants are transported by seepage into local aquifer.
105

Making Music Sustainable: The Case of Marketing Summer Jamband Festivals in the U.S., 2010

Cary, Melissa A. 01 August 2012 (has links)
Commercial music festivals in the United States have been growing in popularity since the 1960s. Today, many weekend-long music festivals are annual events spanning a variety of genres and often occur at the same locations each year. My research compares and contrasts how jamband music festivals are marketed as sustainable events and attempts to determine how the advertised sustainable practices are implemented and utilized at selected jamband music venues. The jamband genre of music emphasizes musical improvisation and borrows from other styles of music: rock, electronic, jazz, blues, folk, and bluegrass. In addition, any impacts these festivals have upon the local environment are evaluated. Sustainability is a topic often used as a marketing strategy when promoting summer jamband music festivals. Fans of this genre are identified with a culture that is similar to the environmentally conscious hippie culture of the 1960s and 1970s. The data for this research were obtained through field observations, interviews, surveys, and content analyses of promotional materials. It is my hypothesis that the festivals’ sustainable practices will be adopted by local communities as the festivals leave both a physical and cultural imprint upon the local landscapes, which is determined through attendee surveys and interviews with local decision makers and festival promoters. I also hypothesize that the geographic location of each will have an influence on the participation in such practices by the festival attendees, as I believe those in attendance at the High Sierra Music Festival in California will be more likely to have green lifestyles as California has been a leader in environmentally conscious innovations and attitudes, whereas other states, Illinois and Tennessee, lag behind. The data collected were mapped and analyzed to determine the effectiveness of environmental sustainability promotions and practices at the fan level as well as the local level. This research fills a gap within the geographic literature as no research exists examining the spatial relationship between music festivals and sustainability. Additionally, my research highlights that popular cultural events can be opportunities to engage in meaningful environmental education on issues such as recycling, and environmental sustainability.
106

Phosphorus Transport and Distribution in Kentucky Soils Prepared Using Various Biochar Types

Reddy, Anvesh 01 December 2012 (has links)
Conserving the environment is an issue that is gaining popularity day by day. Phosphorus transfer from agricultural soils is an important environmental issue that is being closely observed as the transport of phosphorous to water bodies is adversely affecting water quality due to accelerated eutrophication. It is important to establish phosphorous models that accurately account for soil test phosphorous. Standard models like SWAT (Soil and Water Assessment Tool) and EPIC (Environmental Policy Integrated Climate) were designed for serving this purpose. They are now used as the basis for developing new models that can more accurately account for the phosphorus transport, depending on local soil conditions and external factors like climate, addition of biochar or other soil amendments. Our research involved development of new methods from published data that are applied to different soils from Kentucky that are incubated for various time periods, with and without the addition of biochar amendments. Changes in the soil labile phosphorus content after phosphorus addition to and depletion from these incubated soils was measured to discern the effect of biochar on the rates of phosphorus transport. The measured labile phosphorus was further analyzed using statistical analysis software drawing comparisons among treatments without biochar, with low temperature biochar and high temperature biochar for specific soil-biochar combinations. Loamy sand soils with both pine chips and switch grass biochar types have shown slightly increased leeching of phosphorus upon addition of biochar whereas clay loam soils have not shown any significant change upon addition of biochar.
107

Turisme i sostenibilitat. Una proposta metodològica per a l’estudi de la sostenibilitat turística a escala municipal

Torres Delgado, Anna 12 December 2012 (has links)
Avui en dia ningú posa en dubte que l’activitat turística ha de ser una pràctica sostenible que contribueixi al desenvolupament econòmic, l’equitat social, la revalorització cultural i la preservació de l’entorn. Tanmateix, aconseguir un turisme sostenible no és fàcil, sobretot tenint en compte que la imprecisió del concepte dificulta la seva aplicació. La marca de “turisme sostenible” ha passat a adjectivar moltes pràctiques turístiques que difícilment compleixen els principis del desenvolupament sostenible, o bé que ho fan de manera parcial per una de les seves dimensions (normalment l’ambiental). Cal doncs, aclarir el concepte i dotar-lo d’instruments que permetin transformar la idea teòrica en valor pràctic, és a dir, en una sèrie de paràmetres identificables i quantificables. Amb aquest pas el turisme sostenible ha de deixar de ser una estratègia general, amb moltes possibles interpretacions i actuacions, i convertir-se una realitat assolible i adaptada a les circumstàncies específiques de cada lloc. És necessari desenvolupar metodologies d’identificació i quantificació d’impactes del turisme per a facilitar la incorporació de la sostenibilitat en els processos de decisió i gestió. Responent a aquesta necessitat, la tesi aprofundeix en la relació entre la sostenibilitat i el turisme a través de l'elaboració d'una metodologia per estudiar la sostenibilitat turística a escala local. La proposta dóna resposta a una de les principals dificultats en l'aplicació real de la sostenibilitat en el sector: la manca de límits de sostenibilitat turística. I ho fa a través del desenvolupament d’una metodologia basada en indicadors que s'aborda a dos nivells complementaris: el primer amb l'aplicació d'un sistema de 26 indicadors de sostenibilitat social, econòmica i ambiental en diversos casos d'estudi de Catalunya, i el segon amb la construcció d'un Índex de Sostenibilitat Turística (ISOST) elaborat a partir de l'anàlisi empíric realitzat i amb vocació d'ús general. La valoració conjunta d’aquestes dues eines és bàsica per a la correcta interpretació de la sostenibilitat turística municipal i per al disseny d’estratègies de millora. El Sistema d’Indicadors es calcula per 20 municipis representatius de les diferents realitats turístiques i territorials de Catalunya. Precisament l’aplicació del Sistema d’Indicadors en casos d’estudi ha suposat una diferència qualitativa respecte altres propostes, en tant que ha permès garantir-ne la seva mesurabilitat i funcionalitat en l’estudi dels impactes del turisme. També ha permès un tractament analític valuós i profund de la informació indicador a indicador, i la identificació d’aquelles variables clau en la sostenibilitat turística que posteriorment s’agreguen per a crear l’índex ISOST, que en facilita una interpretació global per cada municipi. El càlcul de l’ISOST per la mostra representativa de casos, que s’han tractat dins un marc d’anàlisi comú per a poder distingir patrons generals i factors contextuals propis de cada cas, ha permès establir a la vegada llindars de sostenibilitat turística extrapolables a partir dels quals definir el grau de sostenibilitat turística de qualsevol municipi turístic. La definició de llindars suposa la traducció de la sostenibilitat turística a valors quantificables a través d’una fórmula definida, de manera que l’ISOST esdevé una eina útil en els processos de decisió, planificació i gestió turística municipal. / Achieving sustainable tourism is not easy, mainly because the vagueness of the concept makes its application difficult. It is therefore necessary to clarify the concept and develop the tools to turn the theoretical idea into practical value, which means identifiable and measurable parameters. Methods for identification and quantification of tourism impacts are necessary to incorporate sustainability into decision-making processes and management. Due to this need, the thesis explores the relationship between sustainability and tourism through the development of a methodology for studying sustainable tourism at the municipal level. The proposal responds to one of the most important difficulties in the current implementation of sustainability in the tourism sector: the lack of limits of sustainable tourism. According to this aim, a methodology is developed in two complementary levels: first by the application of a system of 26 social, economic and environmental indicators on several Catalan municipalities; and secondly by the construction of an Index of Sustainable Tourism (ISOST) drawn from the empirical evidences. The System of Indicators is calculated for 20 municipalities, which are representative of different realities and regional tourism in Catalonia. Indeed this application on case studies is a qualitative difference with respect to other proposals, as it ensures measurability and functionality of the tool in the study of tourism impacts. It has also allowed a thorough analytical treatment of information (indicator to indicator), and identify those key aspects in tourist sustainability which are subsequently added to create the index (ISOST). Calculating the ISOST in a representative sample of cases, dealing within a common analytical framework to distinguish general patterns and contextual factors, has allowed to establish tourist sustainability thresholds and define a method for calculating the degree of sustainability of any tourist municipality. The definition of these thresholds is the translation of tourist sustainability into quantifiable values defined by a formula, so that ISOST becomes a useful tool in the decision processes, planning and management of tourism.
108

Near-surface Atmospheric Response to Simulated Changes in Land-cover Vegetation Fraction, and Soil Moisture over Western Kentucky

Leeper, Ronnie 01 August 2009 (has links)
A series of land-use-land-cover-change (LULCC) based sensitivity experiments, including changes in vegetation type, fractional vegetation (FV), and soil moisture (SM), over Western Kentucky were conducted to investigate atmospheric response to land-use. The choice of land-use for this study was chosen in the context of Western Kentucky’s historical LULCC. For this study, vegetation types considered were grassland, forest, and bare soil with further variations in FV for grassland and forest at 25, 50, 75, and 100 % and systematic increases and decreases in volumetric SM of 0.05, 0.10, and 0.15 m3 m-3. To the author’s knowledge, this is the first assessment of its kind that incorporates these types of LULCC in a single study. In addition, typical anthropogenic land-use change often incorporates several types of LULCC. Moreover, this assessment provides a robust analysis of the impacts LULCC has on atmospheric processes over Western Kentucky. To simulate the importance of land-use on atmospheric processes, a well known meso-scale model developed by the National Center for Atmospheric Research (NCAR) and the Pennsylvania State University (PSU) MM5 coupled with an intermediately complex land surface model (LSM) Noah was used. The purpose of this research is to investigate the impact of multiple types of LULCC on planetary boundary layer (PBL) evolution, PBL stability, near surface 3D-wind fields, temperature, and moisture. Furthermore, it is anticipated that multiple types of LULCC will provide more insight into the complex nonlinear land-atmosphere interactions from atmospheric, air quality, and climatology perspectives. Modeling analysis revealed the importance of land-use on atmospheric processes. Changes in all three types of LULCC (land-cover, FV, and SM) altered the distribution of surface energy and moisture, PBL structure, 3D-wind fields, and PBL stability. In general, it was found that LULCC that enhanced (diminished) ET rates reduced (increased) sensible heat flux, atmospheric temperature and, and PBL heights below (above) control (CTRL). For instance, the conversion of land-cover from CTRL to grassland reduced 2 m temperature and PBL heights by 0.60 °C and 228 m respectively compared to CTRL due to an evaporative advantage (lower stomata resistance). Multiple types of land-use change were found to either offset or enhance overall modeled response to LULCC. A reduction in FV to 25 % over grassland diminished ET despite the evaporation advantage of grassland and increased 2 m temperature and PBL heights with respect to CTRL by 3.3 °C and 504 m. These results significantly altered horizontal and vertical wind fields, affecting moisture advection and the development of meso-scale circulations. Compared to CTRL, these differences were enhanced over drier soils, but muted over moist soils. Moreover, the impact of LULCC on atmosphere evolution was not only dependent on the type of LULCC, but also on the current state of other unaltered land surface features such as vegetation type, FV, and SM. Alterations to modeled PBL development, as a result of LULCC, can have important impacts on a region’s climatology and air quality. Simulated changes in typical PBL moisture and temperature through time can affect local and regional climatology. Depending on the type of LULCC, these alterations in climate may lead to localized cooling. In addition, it was further hypothesized that changes in PBL height can affect air quality. Given the capping inversion layer at the top of the PBL, changes in PBL heights can significantly affect air quality with lower (higher) PBL heights diminishing (enhancing) air quality. Moreover, this research prescribes the importance of considering LULCC in atmospheric assessments of climatology and air quality, including pollutant dispersion and trajectory modeling.
109

Developing tools for sustainability management in the graphic arts industry

Enroth, Maria January 2006 (has links)
<p>The main aim of this thesis is to develop and test industry-specific, applied work procedures and tools for environmental and emerging sustainability work in the graphic arts industry. This includes methods to quantify, follow-up, evaluate, manage, improve and communicate the environmental performance of activities in the graphic arts supply chain and printed products.</p><p>In order to achieve the aims of the thesis, a selection of work areas were chosen as the basis for developing the industry-specific work procedures and tools. The selected work areas are the following: environmental management (being a part of sustainability management), environmental and sustainability strategies, environmental indicators and design for environment (DfE).</p><p>The research presented in this thesis was based on survey research methods, case studies and multi-company studies. Within the framework of these methods, quantitative and qualitative techniques for data gathering were used. The companies included in the studies were selected according to their willingness, interest and motivation to participate and develop their environmental or sustainability work.</p><p>The most significant results of the research presented in this thesis regarding the selected work areas are the following:</p><p>• An evaluation of early certified environmental management systems (EMSs) in Sweden identified four areas as priorities in making the EMSs more efficient. Two of them, viz. improvement in the follow-up of environmental work, and the linking of EMSs to product design, were developed for the graphic arts industry. The remaining two areas were clarifying the identification process and assessment of environmental aspects, and streamlining and co-ordinating different management systems.</p><p>• An established and successfully tested working method for formulating and realising corporate sustainability strategies in the graphic arts industry.</p><p>• Industry-specific environmental indicator models for the graphic arts industry with defined methods for standardised inventorying and calculations. These models have been tested, used and approved of by the industry itself.</p><p>• Collected and compiled data for the developed environmental indicator models. Data have been collected from quite a large number of companies (10-20 companies for each of the printing techniques covered, i.e. coldset offset, heatset offset and gravure) over a period of several years.</p><p>• The use of the industry-specific environmental indicator models was developed and illustrated.</p><p>• A described and recommended work procedure for DfE in graphic arts companies including industry-specific tools for applying DfE to printed products, in the form of a manual and a checklist. The checklist was designed so that it can serve as a simple tool for the environmental assessment of printed products. The tools were tested by graphic arts companies.</p>
110

Large-scale analysis of sustainable forest management indicators assessments of air pollution, forest disturbance, and biodiviersity [sic] /

Coulston, John Wesley, Riitters, Kurt. Smith, Gretchen Cole. January 2004 (has links)
Thesis (Ph. D.)--North Carolina State University, 2004. / Title from PDF title page (viewed Mar. 27, 2005). Includes vita. Includes bibliographical references.

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