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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.
81

Greenhouse gas assessment of Brazilian soybean production and postharvest nitrous oxide emissions from crop residues decomposition / Emissões de gases de efeito estufa na cultura da soja e influência dos resíduos culturais nas emissões de óxido nitroso pós-colheita

Raucci, Guilherme Silva 27 February 2015 (has links)
Brazil is one of the world\'s largest producers and exporters of soybeans. The oil and meal obtained from grains are important components of biodiesel and animal feed chains. In recent years, international standards and certifications were developed to promote sustainability in the agricultural supply chain. In this context, greenhouse gases (GHG) emissions in the products life cycle has been the main point of interest to the scientific community and consumers. Few studies have evaluated the GHG emissions in soybean cultivation with specific data for the Brazilian reality. The aim of this study was to evaluate the main sources of GHG in soybean production in the State of Mato Grosso, Brazil. We evaluated 55 farms in the crop years of 2007/08, 2008/09 and 2009/10, accounting for 180,000 hectares of soybean cultivation area and totaling 114 individual situations. The results indicated that the largest source of GHG in the soybean production is the decomposition of crop residues (36%), followed by fuel use (19%), fertilizer application (16%), liming (13%), pesticides (7%), seeds (8%) and electricity consumed at the farms (<1%). The average GHG emissions considering the three crop years were 0.186 kg of CO2eq kg-1 of soybean produced. Based on these results, field experiments were conducted to quantify N2O emissions from the decomposition of soybean crop residues in different climatic regions and harvest periods in Brazil. Our results show that, in field conditions, the contribution of N2O emissions from senesced and desiccated residues that remain on field after soybean harvest are unlikely to represent a significant source of N2O loss above normal background soil emissions. These results were also supported by the laboratory incubation experiment, indicating that the IPCC methodology for estimating N2O emissions from soybean crop residues may provide overestimations for the Brazilian conditions. The results of this study provide relevant and specific information to producers, industry and scientific community regarding the environmental impacts associated with soybean production in Brazil / O Brasil é um dos maiores produtores e exportadores mundiais de soja. O óleo e farelo obtidos dos grãos são componentes importantes das cadeias do biodiesel e ração animal. Nos últimos anos, normas e certificações internacionais foram desenvolvidas para promover a sustentabilidade na cadeia de produção agrícola. Nesse contexto, as emissões de gases de efeito estufa (GEE) no ciclo de vida dos produtos tem sido o principal ponto de interesse para a comunidade científica e consumidores. Poucos estudos avaliaram as emissões de GEE no cultivo da soja com dados específicos para a realidade brasileira. O objetivo deste estudo foi determinar as principais fontes de GEE na produção de soja em Mato Grosso, principal estado produtor brasileiro. Foram coletados dados de 55 fazendas nos anos-safra de 2007/08, 2008/09 e 2009/10, totalizando 114 avaliações. Os resultados indicaram que a maior fonte de GEE na produção de soja é a decomposição de resíduos culturais (36%), seguido pelo uso de combustível (19%), aplicação de fertilizantes (16%), calagem (13%), pesticidas (7%), sementes (8%) e eletricidade consumida nas fazendas (<1%). A emissão média considerando os três anos-safra avaliados foi 0,186 kg de CO2eq kg-1 de soja produzido. Com base nesses resultados, foram desenvolvidos experimentos em campo para quantificação das emissões de N2O proveniente da decomposição dos resíduos culturais da soja em diferentes regiões climáticas e períodos de colheita no Brasil. Adicionalmente, foram realizadas incubações em laboratório com materiais de soja em diferentes estágios de desenvolvimento. Os resultados indicaram que resíduos culturais de soja que permanecem no campo após a colheita não representam uma fonte significativa de N2O. Os resultados obtidos neste estudo fornecem informações relevantes para produtores, indústria e comunidade científica quanto aos impactos ambientais associados à cultura da soja no Brasil
82

Quantifying the global cropland footprint of the European Union's non-food bioeconomy

Bruckner, Martin, Häyhä, Tiina, Giljum, Stefan, Maus, Victor, Fischer, Günther, Tramberend, Sylvia, Boerner, Jan 18 February 2019 (has links) (PDF)
A rapidly growing share of global agricultural areas is devoted to the production of biomass for non-food purposes. The expanding non-food bioeconomy can have far-reaching social and ecological implications; yet, the non-food sector has attained little attention in land footprint studies. This paper provides the first assessment of the global cropland footprint of non-food products of the European Union (EU), a globally important region regarding its expanding bio-based economy. We apply a novel hybrid land flow accounting model, combining the biophysical trade model LANDFLOW with the multi-regional input-output model EXIOBASE. The developed hybrid approach improves the level of product and country detail, while comprehensively covering all global supply chains from agricultural production to final consumption, including highly-processed products, such as many non-food products. The results highlight the EU's role as a major processing and the biggest consuming region of cropland-based non-food products while at the same time relying heavily on imports. Two thirds of the cropland required to satisfy the EU's non-food biomass consumption are located in other world regions, particularly in China, the US and Indonesia, giving rise to potential impacts on distant ecosystems. With almost 39% in 2010, oilseeds used to produce for example biofuels, detergents and polymers represented the dominant share of the EU's non-food cropland demand. Traditional non-food biomass uses, such as fibre crops for textiles and animal hides and skins for leather products, also contributed notably (22%). Our findings suggest that if the EU Bioeconomy Strategy is to support global sustainable development, a detailed monitoring of land use displacement and spillover effects is decisive for targeted and effective EU policy making.
83

Operational Efficiency in the Food and Beverage Industry Through Sustainable Water Consumption

Weber, Christopher 01 January 2019 (has links)
The scarcity of water poses a threat to domestic and global economic sustainability while inhibiting the operational efficiency of food and beverage industry firms. The purpose of this multiple case study was to explore the strategies some food and beverage industry leaders in the United States used for implementing sustainable water consumption practices to improve operational efficiency. The conceptual framework for the study was stakeholder theory. The primary data source was semistructured interviews with 4 food and beverage industry leaders in Wisconsin who have responsibility for implementing their firms' sustainability practices, and the secondary data source was corporate sustainability reports. Thematic analysis was used to analyze data, which resulted in 4 themes: efficient equipment, stakeholder and sustainability focus, water recycling, and supply chain support. The implications of this study for social change include the potential for leaders in the food and beverage industry to use findings to create more sustainable water supplies and demonstrate greater stewardship of the environment.
84

Alfdex Manufacturing Footprint :  <em>Future Expansion Strategy for Production 2014 - a Global Review </em>

Hedström, Robin January 2010 (has links)
<p>Investments in offshore manufacturing have in a historical perspective been taken as a series of separate decisions with a strong focus on cost reduction. This kind of cost is typically narrowed to the cost of purchase or manufacture. The total supply chain costs are hardly ever considered. Investments need to be reviewed within the context of a company´s total market and manufacturing requirements. This will prevent unwanted issues such as extended lead times, greater buffer stocks and excess capacity, uncoordinated strategic responses, conflicts and the failure to be profitable.</p><p>Alfdex, which is a joint venture owned by Alfa Laval and Haldex, provide the global truck and diesel engine market with its products and is for the moment market leader. The future demand will however exceed their current capacity within five years. To avoid that any decision will be made ad hoc this project will identify some essential factors that are significant for a future expansion of production. This will thereafter be adapted for Alfdex situation to recommend where they should expand their future production based on an objective perspective.</p><p>In this project seven markets will be reviewed; North America, Europe, South America, Russia, China, India, and Asia. The manufacturing footprint refers to where a company geographically locates its production. It is based on a long-term perspective and required reasonable strategic thinking and analysis.</p><p>Four essential factors have been identified which will determine Alfdex manufacturing footprint recommendations; the current situation; the market development and capacity need; the issue of costs; global and local conditions and differences together with the supply chain. In addition a scenario matrix and analysis matrix have been developed to support the analysis.</p><p>This work has shown that the most feasible solution, based on what is known today, is to make an onsite expansion in Landskrona, Sweden. By keeping the production in Sweden Alfdex will meet the most qualifications identified in the manufacturing footprint. Additionally a sales person and technical support are required in North America as well as allocating resources to monitor the Chinese market.</p><p>In this version of the report customers’ and suppliers’ names as well as some figures have been concealed. In some cases the information has been replaced by an <strong>X</strong> and in others it has been completely removed.</p>
85

Seismic investigations in the Brunswick No. 6 area, Canada – Imaging and heterogeneity

Cheraghi, Saeid January 2013 (has links)
The Brunswick No. 6 area, which is located in the Bathurst Mining Camp, New Brunswick, Canada, is the focus of this thesis. Almost a decade ago, in order to improve the understanding of the crustal structures and explore for new mineral deposits at depth, three 2D seismic profiles totaling about 30 km and 3D seismic data covering an area of about 38 km2 were acquired from the study area. Petrophysical properties including compressional-wave velocity and density were also measured in two deep boreholes in the area. These data were recovered and reanalyzed, and the improved seismic images interpreted as the main part of this PhD thesis. A prestack DMO and poststack migration algorithm was considered for processing both 2D and 3D data. Processing of 2D data revealed shallow and deep reflections, which correlate well with surface geology. Steeply-dipping reflections, some of which could host mineral deposits, were imaged down to a depth of 6-7 km. Processing of 3D data showed similar results to the processed 2D profiles. Nevertheless, the non-orthogonal nature of the 3D survey, combined with irregular distribution of offsets, azimuths and trace midpoints, caused a severe acquisition footprint masking reflections in the DMO-corrected unmigrated stacked cube. An FK-dip filter in the wavenumber domain was designed to reduce the effects of the acquisition footprint. To better understand wave propagation and scattering effects, calculated acoustic impedance log from the available borehole data was used to estimate vertical scale length using a von Karman autocorrelation function. 2D synthetic models representative of heterogeneity in the area were generated accounting for the estimated scale length. Numerical modeling was used to study the scattering effects on the synthetic models, where some predefined targets were superimposed in the provided 2D heterogeneous medium. The effects of variable source frequency, longer horizontal scale length and petrophysical fluctuations of heterogeneous medium were also investigated. The modeling results indicate that, in the presence of large horizontal, but small vertical scale lengths (structural anisotropy), the identification of mineral deposits is possible in the unmigrated stacked sections, but can be challenging in the migrated sections.
86

The Ecological Footprint of Hostel Tourists in Ontario and Quebec

Purvis, Claire Lynne Jay January 2008 (has links)
In recent years, the impacts of tourism on the environment have indicated an urgent need for sustainability principles to be introduced within the industry. Although problems arise regarding the definition and meanings of sustainability, the Ecological Footprint has been proposed as a key indicator of sustainable tourism. In this study, the ecological footprint was adapted to a tourism context, in order to measure the sustainability of backpacker tourists, who are speculated to be environmentally friendly due to their low budgets and use of few resources. During this study surveys were conducted with 123 backpackers and hostel tourists staying at 8 hostels located throughout Ontario and Quebec. Information was collected on respondents’ food, activity and transportation behaviours, as well as hostel occupancy rates, property sizes, energy usages, and waste management routines. This data was inputted into the ecological footprint calculator to determine the average ecological footprints of backpacker tourists in Ontario and Quebec, and the relationship between the ecological footprint, demographics and travelling behaviours. In addition to the data collected for ecological footprint calculations, information was also gathered on hostel and respondent environmental behaviours. The findings indicate that backpacker tourism is substantially more sustainable than some other forms of international travel, however it is generally not sustainable as an activity. Backpacker ecological footprints were considerably higher than the average footprints of residents in their home countries, indicating the immense impacts of transportation, which accounted for 77% of the average EF in this study. As most backpackers in this study were international travellers, the transportation impacts were often a result of flight emissions and although an inquiry was made into sustainable flight options, it is clear that there is currently no perfect solution for decreasing flight impacts. As a result, reducing the ecological footprint of backpacker tourism to a sustainable level currently appears to be for the most part, impossible. However, as backpacker tourism does contribute to the social and economic sustainability of some areas, minor changes are possible within the sector, to at least make the backpacker market as environmentally sustainable as currently possible.
87

Alfdex Manufacturing Footprint :  Future Expansion Strategy for Production 2014 - a Global Review

Hedström, Robin January 2010 (has links)
Investments in offshore manufacturing have in a historical perspective been taken as a series of separate decisions with a strong focus on cost reduction. This kind of cost is typically narrowed to the cost of purchase or manufacture. The total supply chain costs are hardly ever considered. Investments need to be reviewed within the context of a company´s total market and manufacturing requirements. This will prevent unwanted issues such as extended lead times, greater buffer stocks and excess capacity, uncoordinated strategic responses, conflicts and the failure to be profitable. Alfdex, which is a joint venture owned by Alfa Laval and Haldex, provide the global truck and diesel engine market with its products and is for the moment market leader. The future demand will however exceed their current capacity within five years. To avoid that any decision will be made ad hoc this project will identify some essential factors that are significant for a future expansion of production. This will thereafter be adapted for Alfdex situation to recommend where they should expand their future production based on an objective perspective. In this project seven markets will be reviewed; North America, Europe, South America, Russia, China, India, and Asia. The manufacturing footprint refers to where a company geographically locates its production. It is based on a long-term perspective and required reasonable strategic thinking and analysis. Four essential factors have been identified which will determine Alfdex manufacturing footprint recommendations; the current situation; the market development and capacity need; the issue of costs; global and local conditions and differences together with the supply chain. In addition a scenario matrix and analysis matrix have been developed to support the analysis. This work has shown that the most feasible solution, based on what is known today, is to make an onsite expansion in Landskrona, Sweden. By keeping the production in Sweden Alfdex will meet the most qualifications identified in the manufacturing footprint. Additionally a sales person and technical support are required in North America as well as allocating resources to monitor the Chinese market. In this version of the report customers’ and suppliers’ names as well as some figures have been concealed. In some cases the information has been replaced by an X and in others it has been completely removed.
88

The Ecological Footprint of Hostel Tourists in Ontario and Quebec

Purvis, Claire Lynne Jay January 2008 (has links)
In recent years, the impacts of tourism on the environment have indicated an urgent need for sustainability principles to be introduced within the industry. Although problems arise regarding the definition and meanings of sustainability, the Ecological Footprint has been proposed as a key indicator of sustainable tourism. In this study, the ecological footprint was adapted to a tourism context, in order to measure the sustainability of backpacker tourists, who are speculated to be environmentally friendly due to their low budgets and use of few resources. During this study surveys were conducted with 123 backpackers and hostel tourists staying at 8 hostels located throughout Ontario and Quebec. Information was collected on respondents’ food, activity and transportation behaviours, as well as hostel occupancy rates, property sizes, energy usages, and waste management routines. This data was inputted into the ecological footprint calculator to determine the average ecological footprints of backpacker tourists in Ontario and Quebec, and the relationship between the ecological footprint, demographics and travelling behaviours. In addition to the data collected for ecological footprint calculations, information was also gathered on hostel and respondent environmental behaviours. The findings indicate that backpacker tourism is substantially more sustainable than some other forms of international travel, however it is generally not sustainable as an activity. Backpacker ecological footprints were considerably higher than the average footprints of residents in their home countries, indicating the immense impacts of transportation, which accounted for 77% of the average EF in this study. As most backpackers in this study were international travellers, the transportation impacts were often a result of flight emissions and although an inquiry was made into sustainable flight options, it is clear that there is currently no perfect solution for decreasing flight impacts. As a result, reducing the ecological footprint of backpacker tourism to a sustainable level currently appears to be for the most part, impossible. However, as backpacker tourism does contribute to the social and economic sustainability of some areas, minor changes are possible within the sector, to at least make the backpacker market as environmentally sustainable as currently possible.
89

Exploring the Environmental Impact of A Residential Life Cycle, Including Retrofits: Ecological Footprint Application to A Life Cycle Analysis Framework in Ontario

Bin, Guoshu January 2011 (has links)
The residential sector is recognized as a major energy consumer and thus a significant contributor to climate change. Rather than focus only on current energy consumption and the associated emissions, there is a need to broaden sustainability research to include full life cycle contributions and impacts. This thesis looks at houses from the perspective of the Ecological Footprint (EF), a well-known sustainability indicator. The research objective is to integrate EF and Life Cycle Analysis (LCA) measures to provide an enhanced tool to measure the sustainability implications of residential energy retrofit decisions. Exemplifying single-detached houses of the early 20th century, the century-old REEP House (downtown Kitchener, Canada), together with its high performance energy retrofits, is examined in detail. This research combines material, energy and carbon emission studies. Its scope covers the life cycle of the house, including the direct and indirect consumption of material and energy, and concomitant carbon emissions during its stages of material extraction, transportation, construction, operation, and demolition. The results show that the REEP House had a significant embodied impact on the environment when it was built and high operating energy and EF requirements because of the low levels of insulation. Even though the renovations to improve energy efficiency by 80% introduce additional embodied environmental impacts, they are environmentally sound activities because the environmental payback period is less than two years.
90

Distinguishing Painted dog (Lycaon pictus) footprints from Domestic dog (Canis lupus familiaris) and Hyaena (Crocuta crocuta) footprints in the field – in search of a quantitative method

Scharis, Inger January 2011 (has links)
Population estimation is an important task in all wildlife conservation. Such estimations are often difficult in low-density species such as big carnivores. The painted dog (Lycaon pictus) is an endangered species and the first aim of IUCNs action plan is to assess the size and the distribution of the remaining population. This study is the first step towards a quantitative method to distinguish painted dog footprints from footprints of feral domestic dogs and hyaenas. Footprint photographs were collected and digitally processed and total pad area and angles between the digits and backpad of the paw were measured. Both the pad area and the angles show a statistically significant difference between the species. However, further analysis shows that there is no significant difference in pad area between painted dog females and domestic dog males. Size of the pads alone is therefore not suitable as a measure to determine the species from an unknown footprint. The angles between backpad and digits seem to be more suitable to distinguish between species. Therefore, a combination of pad size and the angle between backpad and digits might be useful to estimate the species from an unknown footprint in the field.

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