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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

The impact of physical planning policy on household energy use and greenhouse emissions /

Rickwood, Peter. January 2009 (has links)
Thesis.
72

City of San Luis Obispo community and municipal operations 2005 baseline greenhouse gas emissions inventory : a professional project /

Chiapella, Geoffrey M. Nuworsoo, Cornelius K. January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2010. / "A report for the Community Development Department of the city of San Luis Obispo" Title from PDF title page; viewed on April 27, 2010. Major professor: Cornelius Nuworsoo, Ph.D., AICP "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the Joint Transportation Planning degree [of] Master of City and Regional Planning/Master of Science in Engineering (Transportation Planning Specialization)." "March 2010." Includes bibliographical references (p. 137-138).
73

Unanticipated Consequences of Regional Greenhouse Gas Policies: Criteria Emissions and the Regional Greenhouse Gas Initiave

Olesniewicz, Timothy J. January 2008 (has links) (PDF)
No description available.
74

Evaluating the use of marginal abatement cost curves applied to greenhouse gas abatement in the UK agriculture

Eory, Veronika January 2016 (has links)
Climate change is arguably the most important global societal challenge. Developing ‘low-carbon societies’, i.e. reducing greenhouse gas (GHG) emissions and adapting to a changing climate, is becoming a policy goal across the globe. Agriculture plays an important role in this transformation. The sector is highly vulnerable to climate variability, and is a significant source of emissions. At the same time, it has potential for reducing GHG emissions and also provides opportunity for carbon sequestration in soils and crop biomass. Policy support for mitigating GHG emissions is being informed by scientific evidence on the effectiveness and costs of mitigation opportunities. This information is frequently depicted in marginal abatement cost curves (MACCs), an assessment tool which can help to visualise the hierarchy of technical measures and their cumulative level of abatement. Similarly to other assessment tools, MACCs’ suitability to provide information has certain limitations. Furthermore, different derivations of MACCs are appropriate to answer different questions. In order to draw both informative and reliable conclusions for policy decisions, the characteristics of the MACCs and the resulting limitations have to be presented clearly. This dissertation seeks to answer the general question whether the agricultural MACCs can be improved so that they provide more comprehensive and tailored information to policy makers. In particular five limitations of the MACCs are discussed: the lack of representation of wider effects, the issue of cost-effectiveness of policy instruments and the inclusion of transaction costs, the uncertainty in the MACCs, the boundaries and the heterogeneity of the analysis. Theoretical frameworks are developed and case study examples are provided for these limitations, and the frameworks are assessed in terms whether they achieve the goal of providing more comprehensive information to policy makers than a conventional MACC. Furthermore, the dissertation summarises the available methodologies and applications in agriculture to enhance the MACCs and provides guidelines for researchers and policy makers about the choice of methods and the communication of the results in order to improve the use of MACCs in the policy process.
75

Effects of grazing and housing management systems on greenhouse gas emissions, blood profiles and meat quality of Nguni goats

Tapiwa, Chikwanda Allen January 2016 (has links)
The broad objective of this study was to evaluate the effects of grazing and housing management systems on greenhouse gas emissions, blood profiles and meat quality of Nguni goats. A total of 64 castrated Nguni goats were used and a housing structure was designed to accommodate the goats as well as evaluate effects of type of floor on greenhouse gases, meat quality, blood metabolites and fatty acid profiles. In the first experiment: Forty-eight castrated Nguni goats, at 6-7 months old were used for herding (H) or tethering (T) management systems and randomly allocated to pens with earth (E) or slatted (S) floors. Gas sampling was done using static chambers and analysed using a SRI 8610C gas chromatography machine. The highest CH4 fluxes were from the manure of herded goats on earth floors (HE). The highest CO2 fluxes were from manure of herded goats that were housed on slatted floors (HS): The highest N2O fluxes were from the manure of tethered goats that were sheltered on slatted floors (TS). It was concluded from the first experiment that goat manure is an important source of GHG that is influenced by grazing and floor type management systems. The second experiment was done to evaluate greenhouse gas (GHG) emission from disused (DP) vs occupied goat pens (OP) with earth (EF) or slatted (SF) floors. Eight previously occupied pens were used in this study. Sixteen goats were randomly put in the pens labelled occupied pens with earth floors (OPEF) and occupied pens with slatted floors (OPSF) resulting in four goats per OP. There were month by pen use; month by floor type; and use by floor type interaction effects (P < 0.05) on CH4 production. Floor type, use (DP vs OP) and month affected (P < 0.05) CH4 production. Manure on earth floors of occupied pens (OPEF) emitted the highest (P < 0.05) methane followed by earth floors of disused pens (DPEF). The least CH4 was emitted from DPSF. There was pen use (DP vs OP) by floor type interaction effect (P < 0.05) on CO2 emission. Floor type and pen use affected (P < 0.05) CO2 production. Manure in occupied pens with slatted floors (OPSF) produced the highest CO2 and the least CO2 was from disused pens with slatted floors (DPSF). Floor type and month influenced (P < 0.05) N2O production. It was concluded that continued use of goat pens increased GHG emissions. However, disused goat pens with manure remain an important source of GHG as they continued to emit quantifiable levels of CH4, CO2 and N2O. The third experiment was done to determine the effects of grazing and housing management systems on the concentrations of blood metabolites, activity of creatine kinase, body weight (BW), body condition score (BCS) and carcass characteristics using 48 castrated Nguni goats. Tethered goats had higher (P<0.05): urea, creatinine, total protein, globulin concentrations and more activity of CK than herded goats. On the other hand, herded goats had higher (P<0.05) plasma glucose (H: 3.39±0.020 vs T: 3.23±0.020 mmol/L), serum albumin (H: 15.30±0.147 vs T: 14.82±0.144 g/L) concentration. It was concluded that serum concentrations of all the metabolites and the activity of CK were sensitive to grazing system. Herding of goats promoted more glucose concentration and preservation of muscle protein and hence superior body weights and BCS than tethered goats. The fourth experiment was done to determine the effects of grazing and housing management systems on the activity of creatine kinase (CK) and cortisol concentration, and chevon quality. Further, the effect of muscle type [Muscularis longissimus thoracis et. Lumborum (LTL) and triceps brachii (TB)] on chevon quality was also investigated. Forty eight castrated Nguni goats aged 6- 7 months were randomly allocated to tethering (n=24) and herding (n=24) treatments. Floor type affected meat (P<0.05) pH24. Tethered goats had higher (P < 0.05) L* and CL percent than herded goats. Muscle type had a significant influence (P < 0.05) on a*, WBSF and pH. It was observed and concluded that T resulted in higher L* and more CL percent whilst SF lowered the pH24 of chevon; at the same time meat from the TB muscle was more tender, despite having a higher pH24 and more CL percent relative to LTH cuts. The fifth experiment was done to determine the effect of grazing and floor type on fatty acid composition of chevon from tethered and herded Nguni goats. Floor type had no effect on fatty acid composition. Oleic, stearic, palmitic and linoleic were the major fatty acids. Chevon from tethered goats had higher (P < 0.05) proportions of long chain polyunsaturated fatty acids (PUFAs): eicosapentaenoic, docosapentaenoic, docosahexaenoic, conjugated linoleic acid (CLA) and more total SFA, total PUFA, total Omega- 6 and total omega 3 fatty acids than herded goats. On the other hand, chevon from herded goats had more (P < 0.05) C18:1c9, C18:2t9, 12 (n-6), C20:3c11, 14, 17 (n-3) and total MUFA than tethered goats. However, there was no difference (P > 0.05) in the PUFA: SFA and n-6/n-3 fatty acid ratios between the herded and tethered goats. It was concluded that tethering promoted higher proportions of beneficial PUFAs which were more in TB than LTH muscle. The overall conclusions from the whole study were that goat manure is an important source of GHG with high CH4 being emitted from earth floors of herded goats. High CO2 and N2O are emitted from SF of herded and tethered goats, respectively. There were no major differences in meat quality between herded and tethered goats. However, herding promoted more live weight gain than tethering. On the other hand, tethering promoted more beneficial fatty acids. Therefore depending on the objective of the enterprise, smallholder farmers can safely tether or herd their goats. Further, there is need to develop technologies to harness CH4 from goat manure.
76

Variabilidade temporal da concentração atmosférica de CO2, fluorescência da clorofila induzida pelo sol e NDVI em áreas com diferentes usos agrícolas no centro-sul do brasil / Temporal variability of CO2 atmospheric concentration, solar induced fluorescence and NDVI in areas under different agricultural uses in the south-central of brazil

Morais Filho, Luiz Fernando Favacho 01 August 2018 (has links)
Submitted by Luiz Fernando Favacho Morais Filho (luiz.morais@unesp.br) on 2018-09-20T13:26:22Z No. of bitstreams: 1 Dissertação Fernando def.pdf: 826650 bytes, checksum: fab3320515ffbd38a313ef8487dd8d26 (MD5) / Rejected by Neli Silvia Pereira null (nelisps@fcav.unesp.br), reason: Solicitamos que realize correções na submissão segundo as orientações abaixo. Art. 1º Os trabalhos produzidos ou publicados, em qualquer mídia, que decorram de atividades financiadas, integral ou parcialmente, pela CAPES, deverão, obrigatoriamente, fazer referência ao apoio recebido. Art. 2º Para fins de identificação da fonte de financiamento fica autorizada a utilização do código 001 para todos os financiamentos recebidos. Art. 3º Deverão ser usadas as seguintes expressões, no idioma do trabalho: "O presente trabalho foi realizado com apoio da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Código de Financiamento 001" Agradecemos a compreensão. on 2018-09-21T16:56:24Z (GMT) / Submitted by Luiz Fernando Favacho Morais Filho (luiz.morais@unesp.br) on 2018-09-21T17:54:52Z No. of bitstreams: 2 Dissertação Fernando def.pdf: 826650 bytes, checksum: fab3320515ffbd38a313ef8487dd8d26 (MD5) Dissertação Definitiva.pdf: 826037 bytes, checksum: d609125d1b8cd12088e625ac1abd0d65 (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-09-21T18:30:33Z (GMT) No. of bitstreams: 1 moraisfilho_lff_me_jabo.pdf: 826037 bytes, checksum: d609125d1b8cd12088e625ac1abd0d65 (MD5) / Made available in DSpace on 2018-09-21T18:30:33Z (GMT). No. of bitstreams: 1 moraisfilho_lff_me_jabo.pdf: 826037 bytes, checksum: d609125d1b8cd12088e625ac1abd0d65 (MD5) Previous issue date: 2018-08-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Brasil é um país que apresenta grande parte do seu território destinado a atividades agrícolas. Os cultivos de cana-de-açúcar, soja e milho têm grande importância na economia nacional. As práticas de manejo de cultivos e do solo estão intimamente ligadas à emissão de CO2 e a produtividade dos cultivos. Essas práticas também interferem no potencial de fotossíntese, que pode ser medido remotamente por satélites pela fluorescência da clorofila induzida pelo sol (SIF), e pelo Índice de Vegetação pela Diferença Normalizada (NDVI). O monitoramento do CO2 atmosférico via satélite vem sendo amplamente utilizado na compreensão dos fluxos de carbono. Neste estudo investigamos a variabilidade temporal do XCO2, o SIF e o NDVI em áreas com os principais cultivos do centro sul do Brasil, cana-de-açúcar, rotação soja-milho e pastagens. O estudo foi realizado em áreas correspondentes à três usos agrícolas, sendo cana-de-açúcar (Pradópolis – SP), rotação soja-milho (Santo Antônio do Paraíso – PR) e pastagens (Águas Claras – MS). As variáveis analisadas foram Temperatura do ar, Pluviosidade, NDVI, SIF e XCO2. Todos os dados foram ajustados em escalas mensais. A Temperatura do ar foi obtida através da plataforma NASAPOWER, a Pluviosidade através da plataforma NASA GIOVANNI, NDVI via SATveg EMBRAPA e SIF e XCO2 a partir da plataforma OCO-2 da NASA. O período de estudo foi de outubro/2014 a outubro/2016, totalizando uma série temporal de dois anos e todos os dados foram estratificados em escala mensal. Nas séries temporais de NDVI, SIF e XCO2 foram removidas as tendências pelo método da regressão. A SIF variou de 0.141 a 0.6 W m-2 sr-1 μm-1 na cana-de-açúcar, 0.01 a 0.724 W m-2 sr-1 μm-1 em grãos e 0.02 a 2.24 W m-2 sr-1 μm-1 na pastagem. O XCO2 oscilou de 397.9 a 400.5 ppm na cana-de-açúcar, de 396.8 a 404.201 ppm em grãos, e de 400.4 a 407.3 ppm na pastagem. A SIF apresentou correlação linear positiva significativa com o NDVI na cana-de-açúcar e nas pastagens, ao passo que apresentou correlação linear negativa com o XCO2 nas três áreas de estudo. O NDVI e a SIF acompanharam a fenologia dos cultivos nas regiões. O pasto apresentou o maior pico de SIF entre as três áreas de estudo. / Brazil’s territory is covered, mostly, by agricultural activities. Sugarcane, soybean and corn cultivation and livestock plays a major role in the national economy. Management practices in the agricultural activity are correlated to CO2 emission. These practices can affect the crop biomass production and photosynthesis activity. Solar-induced Chlorophyll Fluorescence (SIF) can be used to estimate photosynthesis in cultivation areas. Normalized Difference Vegetation Index (NDVI) has been used to estimate biomass production, soil coverage and crops phenology. Recently, atmospheric CO2 monitored using remote sensing has been widely used in the understanding of carbon fluxes, correlating it to other parameter such as gross and net primary production or even the SIF. The aim of this study was to understand the temporal variability of XCO2, SIF and NDVI in areas under sugarcane cultivation, soybean-corn rotation and grassland to livestock production in the South-Central region of Brazil. This research was conducted in three localities, each one corresponding to one agricultural use: Pradópolis – SP (sugarcane cultivation), Santo Antônio do Paraíso (soybean-corn) and Águas Claras – MS (grassland and pasture to livestock). We analyzed temperature, pluviosity, NDVI, SIF and XCO2. Temperature and pluviosity data were obtained using the NASAPOWER and NASA GIOVANNI platform, respectively. NDVI was obtained in the SATveg project (EMBRAPA). SIF and XCO2 data were obtained in the OCO-2 program. We collected data of a 2-year time series (from October/2014 to October/2016). All these data were transformed to monthly scale. The SIF values of sugarcane varied from 0.141 to 0.6 W m-2 sr-1 µm-1 , from 0.01 to 0.724 W m-2 sr-1 µm-1 in cropland (soybean-corn), and 0.02 a 2.24 W m-2 sr-1 µm-1 in the pasture. The XCO2 varied from 397.9 to 400.5 ppm in the sugarcane cultivation, from 396.8 to 404.201 ppm in the cropland and 400.4 to 407.3 ppm in the pasture. SIF showed a significative positive linear correlation to NDVI in sugarcane and pasture, and a significative negative linear correlation to XCO2 in all áreas. The NDVI and SIF parameters were sensible to the plants phenology. / 001
77

Energy emissions input-output analysis in South Africa

Moodley, Shomenthree 29 July 2008 (has links)
Given the energy intensive nature of the South African economy and the country’s dependence on fossil fuels, the reduction of greenhouse gas (GHG) emissions poses a serious problem to poverty alleviation, economic growth and employment. This study assesses the inter-industry and macro-economic impacts of carbon dioxide emissions reduction in South Africa. A monetary energy input-output table was developed using data from supply and use tables and a physical energy-emissions input-output table was developed from the national energy balance and the country’s GHG inventory. Both tables were used to develop the energy-emissions input-output model. Carbon dioxide taxes and energy subsidy reform were selected as potential economic policy instruments for analysis in South Africa. The energy-emissions input-output model was used to analyse the implications of the selected policy scenarios in terms of their effect on gross domestic product (GDP), employment, household consumption, energy consumption and energy emissions reduction. According to the energy-emissions input-output model developed in this study, financial and community services, construction and accommodation and machinery and equipment have the largest final demand and value added while nuclear energy, natural gas and biomass have the smallest final demand and value added. Renewable energy is labour intensive but not energy intensive as this energy sector has the highest labour to value added and the lowest energy to labour and energy to value added ratios. The petroleum products sector is the least labour intensive and the most energy intensive as it has a low labour to value added ratio and high energy to labour and energy to value added ratios. For every one unit increase in biomass, renewable energy and nuclear energy results in the largest increase in output, income and employment while machinery and equipment, natural gas and gold and other mining sectors have the lowest increase in simple and total output, income and employment multipliers. There is not much movement between natural gas, nuclear energy, renewable energy and biomass and the rest of the economy. Coal and crude oil have a relatively moderate impact and are moderately impacted on by other industries in the economy. Although almost all other industries in the economy depend heavily on electricity and petroleum products, these two industries are not as heavily dependent on other industries. Coal is responsible for the largest direct primary energy emissions followed by crude oil while natural gas; nuclear energy, renewable energy and biomass have a low direct impact. The electricity sector accounts for the highest indirect impact on coal emissions and petroleum products have the highest indirect impact on crude oil emissions. The petroleum products sector has the highest indirect impact on natural gas emissions. The electricity sector is largely responsible for the direct impact on coal emissions in terms of total economic output and the petroleum products sector accounts for all crude oil emissions from output. Natural gas, renewable energy, nuclear energy and biomass have no effect on direct emission output ratio. The iron and metals sector has the largest direct impact on electricity emissions per output and transport and communication has the highest direct impact on petroleum products emission per output. The largest indirect coal pollution per output impact is in the electricity sector, followed by petroleum products and iron and metals, while machinery and equipment has the smallest indirect impact on coal emissions per output. Petroleum products have the largest indirect crude oil pollution per output and the petroleum products sector is the only sector with an indirect impact on natural gas emissions per output. The iron and metals sector has the largest indirect electricity emission per output followed by household consumption and financial and community services while natural gas has the smallest indirect electricity emissions per output followed by machinery and equipment. Nuclear energy, renewable energy and biomass have no indirect petroleum products emissions per output. Machinery and equipment and crude oil have the lowest indirect petroleum products emissions per output. Inter-industry analysis indicates that the tax on coal results in the largest decrease in total output in the electricity and petroleum products sectors while output in the petroleum products and gold and other mining sectors decreases the most with the tax on oil. The tax on electricity has the largest negative impact on the iron and metals and financial and community services sectors and the tax on petroleum products results in the largest decrease in the transport and communication and financial and community services sectors. The electricity and coal mining sectors suffer the largest decrease in output as a result of energy subsidy reform. Macro-economic impacts were analysed according to real and marginal decreases. Real changes were used to assess the impact of each policy in terms of direct changes to each specific variable. Marginal decreases were calculated as a ratio of decreasing GDP for each variable hence marginal employment equals change in employment as a ratio of change in GDP and marginal household consumption equals change in household consumption as change a ratio of change in GDP. Marginal excess burden of taxes was calculated as changes in tax revenue, as a ratio of decrease in GDP. In terms of decreasing GDP, employment and household consumption, the lower the marginal burden the better the policy. Although the tax on coal offers the highest reduction in real energy emissions, this scenario also results in the highest reduction in GDP, employment and household consumption. Therefore the coal tax is not considered as the best option for carbon dioxide emissions reduction in South Africa. The electricity tax offers a moderate reduction in real energy emissions, GDP, employment and household consumption. It is concluded that the electricity tax could be an option for carbon dioxide emissions reduction in South Africa. However energy subsidy reform offers higher energy emissions reduction and a moderate reduction in GDP, employment and household consumption. This scenario is recognised as the most efficient option for carbon dioxide reduction in South Africa in terms of real changes. The tax on coal indicates high marginal decreases in employment and household consumption, moderate marginal tax revenue and moderate marginal decrease in energy consumption and energy emissions reduction. The tax on crude oil indicates low marginal decreases in employment and household consumption, low marginal excess burden on taxes, low marginal decrease in energy consumption and a moderate marginal decrease in energy emissions. The tax on petroleum products indicates low marginal decreases in employment and household consumption, low marginal excess burden on taxes and a high marginal decrease in energy consumption and energy emissions. Energy subsidy reform offers moderate marginal decreases in employment and household consumption, low marginal excess burden on taxes and a low marginal decrease in energy consumption and energy emissions. The comparison of marginal burdens of energy emissions reduction policies indicates that energy subsidy reform offers the best option as this scenario has moderate marginal decreases in employment and household consumption, low marginal excess burden on taxes and a low marginal decrease in energy consumption and energy emissions. The tax on crude oil is selected as the second best alternative as this scenario has low marginal decreases in employment and household consumption, low marginal excess burden on taxes, low marginal decrease in energy consumption and a moderate marginal decrease in energy emissions. Therefore in terms of real and marginal reduction in energy emissions, energy consumption, GDP, employment and household consumption, energy subsidy reform proves to be the best policy instrument in terms of energy emissions reduction, energy consumption, poverty alleviation, economic growth and employment. / Thesis (PhD)--University of Pretoria, 2008. / Agricultural Economics, Extension and Rural Development / unrestricted
78

Investigation of Microalgae Growth Kinetics Using Coal-Fired Flue Gas as a Carbon Source

Brooker, Bryan Daniel 01 June 2011 (has links) (PDF)
ABSTRACT Investigation of Microalgae Growth Kinetics using Coal-Fired Flue Gas as a Carbon Source Bryan Daniel Brooker Energy related carbon dioxide (CO2) emissions make up the majority of the United States’ greenhouse gas emissions. Emissions must be alleviated to reduce the effects of global climate change. Microalgae cultivation sequesters CO2 while producing biomass. Algal biomass can provide a renewable feedstock for biofuel and electricity production, and ingredients for pharmaceuticals, nutraceuticals, pigments and cosmetics. Utilizing microalgae to mitigate CO2 emissions encourages energy independence by providing a feedstock for biofuels and offers other potentially profitable avenues for the uses of biomass. This study focused on investigating the algal growth kinetics of microalgae cultivated with artificial coal-fired flue gas. Two algal strains, Chlorella vulgaris and Tetraselmis sp. were cultivated in lab scale photobioreactors to assess the feasibility of using flue gas as a carbon source for microalgae growth. The microalgae growth kinetics were compared between flue gas and pure CO2 treatments for each algal strain. Both microalgae species were able to grow under flue gas dosing. The differences in growth characteristics for Chlorella were statistically insignificant between the two gas dosing treatments. Tetraselmis yielded identical maximum specific growth rates among the two gas treatments, while the biomass production was greater using CO2. At a 95% confidence interval, the difference in biomass production between the gas treatments ranged from 45 to 225 mg/L. The decrease in biomass production for Tetraselmis was the only sign of growth inhibition from flue gas. Overall, Chlorella vulgaris and Tetraselmis sp. are capable of fixating CO2 from coal-fired flue gas.
79

Biogenic Methane and Nitrous Oxide Emissions from the Wastewater Collection System in Cincinnati, Ohio

Fries, Anastasia E. 12 September 2017 (has links)
No description available.
80

Carbon Footprint Accounting Using Various Tools and Techniques, Comparison and Uncertainties

Sharma, Neha January 2010 (has links)
No description available.

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