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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.
71

Current and future economic impact of Mount Hood National Forest outdoor recreation consumption /

Anderson, David M January 1991 (has links)
Thesis (M.S.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references (leaves 80-89). Also available on the World Wide Web.
72

Measuring the factor content of trade

May, Sharon Lee, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 127-129).
73

Consumption-based material flow indicators - Comparing six ways of calculating the Austrian raw material consumption providing six results

Eisenmenger, Nina, Wiedenhofer, Dominik, Schaffartzik, Anke, Giljum, Stefan, Bruckner, Martin, Schandl, Heinz, Wiedmann, Thomas, Lenzen, Manfred, Tukker, Arnold, Arjan, de Koning January 2016 (has links) (PDF)
Understanding the environmental implications of consumption and production depends on appropriate monitoring tools. Material flow accounting (MFA) is a method to monitor natural resource use by countries and has been widely used in research and policy. However, the increasing globalization requires the consideration of "embodied" material use of traded products. The indicator raw material consumption (RMC) represents the material use - no matter where in the world it occurs - associated with domestic final demand. It provides a consumption-based perspective complementary to the MFA indicators that have a territorial focus. Several studies on RMC have been presented recently but with diverging results; hence, a better understanding of the underlying differences is needed. This article presents a comparison of Austrian RMC for the year 2007 calculated by six different approaches (3 multi-regional input-output (MRIO) and 3 hybrid life-cycle analysis-IO approaches). Five approaches result in an RMC higher than the domestic material consumption (DMC). One hybrid LCA-IO approach calculates RMC to be lower than DMC. For specific material categories, results diverge by 50% or more. Due to the policy relevance of the RMC and DMC indicators it is paramount that their robustness is enhanced, which needs both data and method harmonization.
74

Frameworks for estimating virtual water flows among U.S. states

Mubako, Stanley T. 01 May 2011 (has links)
The United States is the world's top virtual water exporting nation, but not much is known about the country's internal virtual water flow patterns and the volumes involved. Previous studies have suggested that the import of virtual water, defined as the volume of water required to produce a commodity or service, can relieve pressure on a region's water resources. This study seeks to quantify virtual water flows among U.S. states using the water footprint and input-output analytical methods, and to compare the quantitative results to actual water use volumes in agriculture. The results showed an overall pattern where virtual water is transferred from sparsely populated states mostly in the Midwest, where the country's most fertile agricultural land is located, to the relatively dry Western states, and to the densely populated, but relatively wet coastal regions in the East of the country. For the year 2008, states used 196 Gm3 of water to produce agricultural commodities (crops and livestock) that were exported for consumption in other states. This total virtual water export volume is equivalent to 35 percent of total water withdrawals for all sectors in the U.S., or 41 percent of total rainfall evapotranspiration volume. Gross annual virtual water import volumes were 191 Gm3, giving a net interstate virtual water flow volume of 5 Gm3 for all states. The total virtual water import volume represent 34 percent of total water withdrawals in the U.S., or 40 percent of total rainfall evapotranspiration volume. The estimates in this study cover virtual water flows as a result of trade in 9 primary crops which represent 95 percent of the cultivated area harvested, and trade in nine primary animals that represent nearly 90 percent of animal establishments, and 97 percent of the total national sales in the U.S. for the year 2008. The estimates do not include virtual water flows as a result of trade in processed crop and livestock products and industrial products, which would have resulted in even higher virtual water flow volumes. Commodities making the greatest call on the nation's water resources were corn for grain, with 20 percent of total water use, and milk cows with 17 percent. The total evapotranspiration volume for the nine primary crops analyzed was 332 Gm3/yr. This consists of 93 Gm3 irrigation water (excluding 25 percent irrigation losses), and 239 Gm3 from rainfall, showing that rainfall contributed 72 percent of the total water volumes required to produce primary crops. If irrigation return flows are considered, the proportion contributed by rainfall becomes 65 percent, compared to 35 percent (128 Gm3) for irrigation water. The nine live animals for all states used 636 Gm3 in 2008, with beef cattle taking up 340 Gm3, or 53 percent of the total volumes used for animal production. Net virtual water exports in absolute terms ranged from 91 Mm3/yr in the state of Washington, to 15 Gm3/yr in Iowa, while the minimum net virtual water import value was 47 Mm3/yr in Vermont, to 11 Gm3/yr in Florida. On a per capita basis, the people of North Dakota were responsible for the largest agricultural net virtual export volume (16,011 m3/yr/ca), although the state has only 0.2 percent of the national population. Washington was responsible for the lowest per capita net virtual water export (375 m3/yr/ca). The people of Delaware (0.3 percent the total population) were responsible for the largest net virtual water imports related to agricultural commodities on a per capita basis (1511 m3/yr/ca), with Nevada ranking lowest. In absolute terms, water footprint values in relation to the 18 primary crops and livestock groups ranged from 1157 Mm3/yr in Rhode Island, to 61,471 Mm3/yr in California. Water footprint per capita values ranged from 1,083 m3/yr/capita in New York, to 4,872 m3/yr/capita in Nebraska. Both water footprint and input-output methodologies showed that virtual water transfer constitutes a substantial portion of the water balance in water scarce states such as California, where imports and exports were found to be 13 and 15 percent of total actual water use. The ratios of net virtual water import to agricultural water use volumes were very high for relatively humid states such as Rhode Island (nearly 5,000 percent) and Connecticut (more than 3,500 percent), partly showing that factors related to economic structure dominate climatic factors (water endowments) in shaping virtual water flow patterns in most U.S. states. These results suggest that rather than being the main reason behind observed virtual water flow patterns, water availability is complimentary to other factors of production, mainly the availability of suitable agricultural land. Similar to Japan or some European countries, most highly states in the eastern part of the country rely heavily on virtual water imports to meet their local agricultural consumption requirements, while their economies focus on sectors that are less land and water intensive, such as the services industry. The study also revealed that the volumes of international virtual water imports and exports are dwarfed by internal (interstate) virtual water volumes in the U.S., showing an overall preference for home consumption to international trade. The productive value of water ($/m3 used) was found to be much higher for industry and domestic sectors, in comparison to more water intensive agricultural use. While input-output analysis appears less prone to estimation errors and is less laborious to implement, it is limited in assessing the virtual water content of individual commodities when compared to water footprint analysis. However, the two alternative methodologies both produced results that are to a large extent consistent with production and consumption patterns in the U.S. The study adds new insights and information to earlier global studies that did not elaborate much on the internal virtual water flow dynamics of the world's largest virtual water exporter. The knowledge is relevant for this large country, where there are wide variations in water and other natural resource endowments between regions.
75

Measuring telecouplings in the global land system: A review and comparative evaluation of land footprint accounting methods

Bruckner, Martin, Fischer, Günther, Tramberend, Sylvia, Giljum, Stefan 23 March 2015 (has links) (PDF)
In an increasingly globalized world with more and more distributed international supply chains, sustainability studies and policies need to consider socioeconomic and environmental interactions between distant places. Studies of the global biomass metabolism investigate physical flows between and within nature and human systems, thus providing a useful basis for understanding the interrelatedness of changes in one place with impacts elsewhere. Various methodological approaches exist for studying the human-nature metabolism and estimating the land embodied in international trade flows, a core element of assessing telecouplings in the global land system. The results of recent studies vary widely, lacking robustness and thus hampering their application in policy making. This article provides a structured overview and comparative evaluation of existing accounting methods and models for calculating land footprints. We identify differences in available accounting methods and indicate their shortcomings, which are mainly attributable to the product and supply chain coverage and detail, and biases introduced by the use of monetary flows as a proxy for actual physical flows. We suggest options for further development of global land footprint accounting methods, particularly highlighting the advantages of hybrid accounting approaches as a framework for robust and transparent assessments of the global displacement of land use.
76

Towards Robust, Authoritative Assessments of Environmental Impacts Embodied in Trade: Current State and Recommendations

Tukker, Arnold, de Koning, Arjan, Owen, Anne, Lutter, Franz Stephan, Bruckner, Martin, Giljum, Stefan, Stadler, Konstantin, Wood, Richard, Hoekstra, Rutger January 2018 (has links) (PDF)
Global multiregional input-output databases (GMRIOs) became the standard tool for track ing environmental impacts through global supply chains. To date, several GMRIOs are available, but the numerical results differ. This paper considers how GMRIOs can be made more robust and authoritative. We show that GMRIOs need detail in environmentally relevant sectors. On the basis of a review of earlier work, we conclude that the highest uncertainty in footprint analyses is caused by the environmental data used in a GMRIO, followed by the size of country measured in gross domestic product (GDP) as fraction of the global total, the structure of the national table, and only at the end the structure of trade. We suggest the following to enhance robustness of results. In the short term, we recommend using the Single country National Accounts Consistent footprint approach, that uses official data for extensions and the national table for the country in question, combined with embodiments in imports calculated using a GMRIO. In a time period of 2 to 3 years, we propose work on harmonized environmental data for water, carbon, materials, and land, and use the aggregated Organization for Economic Cooperation and Development (OECD) Inter-Country Input-Output GMRIO as default in combination with detailing procedures developed in, for example, the EXIOBASE and Eora projects. In the long term, solutions should be coordinated by the international organizations such as the United Nations (UN) Statistical Division, OECD, and Eurostat. This could ensure that when input-output tables and trade data of individual countries are combined, that the global totals are consistent and that bilateral trade asymmetries are resolved.
77

Grau de interdependência e setores-chave da economia brasileira contemporânea: um estudo fundamentado na análise de redes / Degree of interdependence and key sectors of the contemporary brazilian economy: a study based on analysis of networks

Michael Moura Martins 02 April 2009 (has links)
Este trabalho mostra como a teoria sobre redes sociais pode ser útil para se realizar análises de dependência intersetorial. Mais especificamente, este trabalho busca identificar os setores produtivos que exercem maior poder de influência - seja de forma positiva ou negativa sobre o sistema econômico nacional, ou seja, os setores-chave da economia brasileira. Para tanto, utiliza-se como base a matriz brasileira de insumo-produto de 1996 atualizada com dados do sistema de contas nacionais referentes ao ano de 2002. Sob uma perspectiva da teoria sobre redes sociais e com o uso do software UCINET, foram criadas duas redes que representassem as relações dos setores produtivos da economia brasileira: a primeira enfatiza as origens dos insumos utilizados pelo sistema produtivo nacional, já a segunda destaca os destinos desses insumos. Com essas redes somadas aos cálculos de índices oriundos dessa mesma teoria concluiu-se que os setores que mais impactam sobre o sistema produtivo brasileiro e, portanto, merecedores de atenção especial por parte dos formuladores de políticas econômicas são: Famílias, Agropecuária, Resto do Mundo, Refino de Petróleo e Construção Civil. Além disso, também, concluiu-se que as redes que representam os setores brasileiros são: densas, possuem baixas distâncias geodésicas, apresentam elevados coeficientes de cluster e têm graus de centralidade elevados, o que faz com que as oscilações de produção em determinado setor produtivo se propague pelo resto da economia rapidamente. / This work shows how the theory on social networks can be useful for analysis of inter dependence. More specifically, this work seeks to identify the productive sectors that have more power of influence - is a positive or negative - on the national economic system, ie the key sectors of the Brazilian economy. For both, were used as the base matrix of input-output Brazilian 1996 updated with data from the system of national accounts for the year 2002. From a perspective of the theory on social networks and with using the software UCINET, two networks were created that represented the relationship of the productive sectors of the Brazilian economy: the first emphasizes the origins of the inputs used by the national productive system and the second highlights the destinations these inputs. With these networks - added to the calculations of indices from that theory - it was concluded that the sectors that exert greater powers of influence on the Brazilian productive system, and therefore deserving of special attention by policy-makers are economic: Families, Agricultural, Rest of the World, Oil Refining and Construction. In addition, it was concluded that the networks that represent the sectors Brazilians are dense, have low geodesic distances, have high coefficients of cluster and have high degrees of centrality, which means that fluctuations of output in a productive sector spreads rapidly through the rest of the economy.
78

Avaliação socioeconômica e ambiental de sistemas de recolhimento e uso da palha de cana-de-açúcar / Socioeconomic and environmental evaluation of recovery systems and use of sugarcane straw

Cardoso, Terezinha de Fátima, 1969- 08 November 2014 (has links)
Orientadores: Luis Augusto Barbosa Cortez, Marcelo Pereira da Cunha / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-25T21:19:54Z (GMT). No. of bitstreams: 1 Cardoso_TerezinhadeFatima_D.pdf: 3738702 bytes, checksum: e368bb547a1651b00f2e7c3133f1f8aa (MD5) Previous issue date: 2014 / Resumo: A colheita de cana crua, sem queima, tem sido imposta principalmente por questões ambientais e com vistas ao aproveitamento integral da cana-de-açúcar. Questões econômicas, ambientais e sociais induzem à mecanização da colheita, o que pode proporcionar melhores condições de trabalho e o aproveitamento da palha, com a eliminação da queima prévia. Parte da palha pode ser utilizada para cobertura do solo, melhorando o reciclo de nutrientes, a retenção de água e redução da erosão. Outra parte da palha poderá ser recolhida, enviada para a indústria e utilizada para geração de eletricidade e/ou para produção de etanol de 2ª geração. Este trabalho, com auxílio da Biorrefinaria Virtual de Cana-de-açúcar (BVC/CTBE), empregou as metodologias de insumo-produto e análise de ciclo de vida (ACV) para analisar os impactos socioeconômicos e ambientais do recolhimento e aproveitamento da palha de cana-de-açúcar no setor sucroenergético, considerando (i) a tecnologia de colheita existente (colhedora Convencional) e em desenvolvimento (Estrutura de Tráfego Controlado ¿ ETC, proposta de mecanização com redução e controle do tráfego), (ii) a parcela de palha recolhida, (iii) a forma de recolhimento e transporte e (iv) seu uso. Avaliou-se, também, a viabilidade econômica de cada rota tecnológica considerada. Verificou-se que a colheita integral é economicamente vantajosa na fase agrícola e que a redução da densidade de carga pode ser compensada com menor perda de colmos, devido à redução de potência dos extratores da colhedora. O enfardamento apresenta custos elevados para pequenas frações de recolhimento devido à redução na capacidade operacional das máquinas. A análise do modelo verticalizado de produção (fase agrícola e industrial) mostrou que a baixa eficiência da estação de limpeza a seco interfere diretamente nos rendimentos da indústria, diminuindo a vantagem da colheita integral. A proposta de recolher palha através de colheita integral com palha repicada apresentou bons resultados nas simulações, reduzindo o custo de transporte e melhorando a eficiência de separação da palha na indústria. Considerando o modelo verticalizado de produção, fardos 7,5 t/ha (com colhedora convencional) e Integral sem ponteiro repicada (ETC) apresentam maiores valores para TIR, 12,0% e 14,2%, respectivamente. A fase agrícola responde por 80% a 90% dos impactos ambientais, variando de acordo com o cenário e a categoria de impacto analisada. O uso e produção de fertilizantes e corretivos são os itens que mais ocasionam os impactos ambientais, seguidos de uso de óleo diesel. Em termos socioeconômicos, a colheita integral apresenta maior valor de produção e PIB; já os cenários com fardos apresentam maior remuneração mensal média por emprego e número de empregos gerados em função do maior número de operações mecanizadas demandando mais mão de obra. O resultado principal do estudo mostra que os cenários com ETC apresentam maior eficiência econômica e a proposta de recolhimento através de colheita integral com palha sem ponteiro e repicada apresentou maior atratividade econômica com menores impactos ambientais. Esta pesquisa demonstra a importância de desenvolvimento de tecnologias que permitam melhor aproveitamento da biomassa / Abstract: Harvesting of green sugarcane, without burning, has been imposed mainly by environmental issues and aiming to take full advantage of sugarcane. Economic, environmental and social issues induce mechanical harvesting, which can provide better working conditions and the use of straw, with the elimination of the previous burning. Part of the straw can be used for soil coverage, enhancing the recycling of nutrients, water retention and reducing erosion. Another part of the straw can be collected, sent to the industry and used for bioelectricity generation or production of 2nd generation ethanol. This paper, with the support of Virtual Sugarcane Biorefinery (VSB), applied input-output and life cycle analysis methodologies to analyze the socioeconomic and environmental impacts of collection and utilization of straw sugarcane, considering (i) harvesting of sugarcane existing (conventional harvester) and developing (ETC - Controlled Traffic Structure ¿ proposed mechanization of reduction and traffic control) technologies, (ii) fraction of gathered straw, (iii) form of collection and transportation and (iv) use of straw. It was also evaluated economic viability of each technological route considered. It was found that the integral harvest system is economically advantageous in the agricultural phase, and that the load density reduction is almost matched with lower loss of stalks due to the reduced power of the harvesters¿ exhauster. The baling system shows higher costs of small fractions straw recovery due to reduction of the machines operational capacity. The verticalized production model analysis (agricultural and industry fases) showed that the low efficiency of dry cleaning station directly interferes with the industry output, reducing the advantage of the integral harvest system. The proposal to collect straw through integral harvest with chopping presented good results in simulations, reducing the cost of transport of straw and improving industrial productivity with better separation of straw. Considering the verticalized production model, 7,5 ton/ha baling (with conventional harvester) and integral harvest system chopped without tops (ETC) present higher values of IRR, 12,0% and 14,2%, respectively. Regarding environmental impacts, it was found that agricultural phase represents 80% ¿ 90% of the environmental impacts, varying according to the analyzed scene and the impact category. The use and production of fertilizers and soil correctors are the items that cause the most environmental impacts followed by the use of diesel. In socioeconomic terms the integral harvest system presents higher production value and GDP (Gross Domestic Product); the baling scenes present higher average monthly income per job and number of generated jobs due to higher number of mechanized operations requiring more manpower. The main result of this study shows that ETC scenes present higher economic efficiency and the recovery proposal of integral harvest system chopped without tops presented higher economic prospects with lower environmental impacts. This paper shows the importance of technology development which permits better use of biomass / Doutorado / Maquinas Agricolas / Doutora em Engenharia Agrícola
79

Recent Progress in Assessment of Resource Efficiency and Environmental Impacts Embodied in Trade: An Introduction to this Special Issue

Tukker, Arnold, Giljum, Stefan, Wood, Richard January 2018 (has links) (PDF)
This paper serves as an introduction to this special issue on the use of multiregional input- output modeling in assessments of natural resource use and resource use efficiency. Due to globalization, growth in trade has outpaced growth in global gross domestic product (GDP). As a consequence, impacts of consumption of a country increasingly take place abroad. Various methods have been developed to perform so-called footprint analyses. We argue that global multiregional input-output (GMRIO) analysis has the largest potential to provide a consistent accounting framework to calculate a variety of different footprint indicators. The state of the art in GMRIO has, however, various shortcomings, such as limited sector and regional detail and incomplete extensions. The work presented in this special issue addresses a number of such problems and how to possibly overcome them, focusing on the construction of a new GMRIO database (EXIOBASE V3). This database includes long time series in both current and constant prices, a high level of product and sector detail, a physical representation of the world economy, and allows analyzing which footprints out of the many possible indicators provide most information for policy making. Various options for empirical analyses are presented in this special issue. Finally, we analyze how GMRIOs can be further standardized and gradually moved from the scientific to the official statistical domain.
80

A review and comparative assessment of existing approaches to calculate material footprints

Lutter, Franz Stephan, Giljum, Stefan, Bruckner, Martin 16 April 2016 (has links) (PDF)
Effective implementation of resource policies requires consistent and robust indicators. An increasing number of national and international strategies focussing on resource efficiency as a means for reaching a green economy call for such indicators. As supply chains of goods and services are increasingly organised on the global level, comprehensive indica-tors taking into account upstream material flows associated with internationally traded products need to be compiled. Particularly in the last few years, the development of con-sumption-based indicators of material use also termed material footprints has made considerable progress. This paper presents a comprehensive review of existing methodol-ogies to calculate material footprint-type indicators. The three prevailing approaches, i.e. environmentally extended input-output analysis (EE-IOA), coefficient approaches based on process analysis data, and hybrid approaches combing elements of EE-IOA and process analysis are presented, existing models using the different approaches discussed, and advantages and disadvantages of each approach identified. We argue that there is still a strong need for improvement of the specific approaches as well as comparability of re-sults, in order to reduce uncertainties. The paper concludes with recommendations for further development covering methodological, data and institutional aspects.

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