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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.
61

Spatial variation of soil methane and nitrous oxide emissions in subarctic environments of Churchill, Manitoba

Churchill, Jacqueline A. 07 June 2007 (has links)
Global warming, associated with elevated levels of greenhouse gases is expected to alter hydrologic regimes, permafrost extent and vegetation composition in the Hudson Bay Lowlands (HBL). Greenhouse gas (respiration, CH4 and N2O; GHG) emissions and soil gas concentrations were determined over the growing seasons of 2005 and 2006 from numerous habitats within three dominate ecosystems within the HBL, a polygonized-peat plateau, northern fringe boreal forest and palsa fen, near Churchill, Manitoba. Nitrous oxide emissions and soil concentrations were near zero however, a trend for very slight production of N2O was observed at dry aerobic sample positions while very slight consumption occurred at very wet sample locations. “Hot-spots” of intense CH4 emissions and soil concentrations occurred in the sedge-dominated areas of high moisture and plant productivity, whereas areas of low moisture and plant productivity resulted in slight CH4 consumption. Of all the ecosystems studied, the palsa fen had the greatest CH4 production, with carbon losses from CH4 occurring at rates of approximately 50 g C m-2 during the growing season. A peat plateau ecosystem site was also used to compare GHG emissions using a similar vegetation type (Cladina stellaris) and under differing soil conditions. Based on the results, slight gradients in soil conditions such as moisture content, peat accumulation and active layer depths altered respiration emissions but did not significantly affect CH4 and N2O fluxes. The differences in GHG emissions were not as great as those between different plant community types, which suggest plant community types could be used to predict GHG emissions in similar environments.
62

Development of Greenhouse Gas Mitigation Options for Albertas Energy Sector

Subramanyam, Veena 11 1900 (has links)
Alberta is the third largest economy in Canada and is expected to grow significantly in the coming decade. The energy sector plays a major role in Albertas economy. The objective of this research is to develop various greenhouse gas (GHG) mitigations scenarios in the energy demand and supply sectors for the Province of Alberta. This is done through an energy-environment planning and forecasting tool called Long Range Energy Alternative Planning system model (LEAP). By using LEAP, a sankey diagram for energy and emission flows for the Province of Alberta has been developed. A reference case also called as business-as-usual scenario was developed for a study period of 25 years (2005-2030). The GHG mitigation scenarios encompassed various demand and supply side scenarios. In the energy conversion sector, mitigation scenarios for renewable power generation and inclusion of supercritical, ultra-supercritical and integrated gasification combined cycle (IGCC) plants were investigated. In the oil and gas sector, GHG mitigation scenarios with carbon capture and sequestration (CCS) option were considered. In Albertas residential and commercial sector 4-6 MT of CO2 equivalents per year of GHG mitigation could be achieved with efficiency improvement. In the industrial sector up to 40 MT of CO2 equivalents per year of GHG reduction could be achieved with efficiency improvement. In the energy conversion sector large GHG mitigation potential lies in the oil and gas sector and also in power plants with carbon capture and storage (CCS) option. The total GHG mitigation possible in the supply side option is between 20 70 MT CO2 equivalents per year. / Engineering Management
63

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

Rickwood, Peter January 2009 (has links)
This thesis investigates the impact of physical planning policy on combined transport and dwelling-related energy use by households. Separate analyses and reviews are conducted into dwelling-related and transport-related energy use by households, before a model is developed to investigate the city-wide implications of different land-use scenarios in Sydney, Australia. The analysis of household energy use in Chapter 3 suggests that medium density housing (i.e. lose-rise apartments, townhouses, and terraces) is likely to result in the lowest per-capita energy use, while also allowing for sufficient densities to make frequent public transport service viable. The analysis of transport energy in Chapter 4 confirms that increasing urban density is associated with decreased car ownership and use, independent of other factors. However, land use changes alone are likely to result in modest changes to travel behaviour. The results of the scenario modelling in Chapters 7-9 support the view that changes to land use alone can reduce household energy consumption, but the changes, even over a long time period (25 years) are small (~0-10%) for all but the most extreme land-use policies. Instead, a coordinated (land-use/transport and other policy levers) approach is much more effective. The results confirm that it is transport energy that is most sensitive to planning policy, but that a combined consideration of dwelling-related and transport-related energy use is still useful. The micro-simulation model developed to assess the impact of different land-use planning scenarios allows the establishment of a lower-bound estimate of the effect that housing policy has on household energy use, assuming ‘business as usual’ transport policy, household behaviour, and technology.
64

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

Rickwood, Peter January 2009 (has links)
This thesis investigates the impact of physical planning policy on combined transport and dwelling-related energy use by households. Separate analyses and reviews are conducted into dwelling-related and transport-related energy use by households, before a model is developed to investigate the city-wide implications of different land-use scenarios in Sydney, Australia. The analysis of household energy use in Chapter 3 suggests that medium density housing (i.e. lose-rise apartments, townhouses, and terraces) is likely to result in the lowest per-capita energy use, while also allowing for sufficient densities to make frequent public transport service viable. The analysis of transport energy in Chapter 4 confirms that increasing urban density is associated with decreased car ownership and use, independent of other factors. However, land use changes alone are likely to result in modest changes to travel behaviour. The results of the scenario modelling in Chapters 7-9 support the view that changes to land use alone can reduce household energy consumption, but the changes, even over a long time period (25 years) are small (~0-10%) for all but the most extreme land-use policies. Instead, a coordinated (land-use/transport and other policy levers) approach is much more effective. The results confirm that it is transport energy that is most sensitive to planning policy, but that a combined consideration of dwelling-related and transport-related energy use is still useful. The micro-simulation model developed to assess the impact of different land-use planning scenarios allows the establishment of a lower-bound estimate of the effect that housing policy has on household energy use, assuming ‘business as usual’ transport policy, household behaviour, and technology.
65

U.S. climate policy and technology : the Bush administration and American conceptions of environmental challenges /

Schniering, Peter. January 2008 (has links)
Diss--Bonn,Univ., 2007.
66

The politics of counting carbon lessons from the California Climate Action Registry /

Mazurek, Jan, January 2008 (has links)
Thesis (Ph. D.)--UCLA, 2008. / Vita. Includes bibliographical references (leaves 197-198).
67

Agroecosystem management effects on carbon and nitrogen cycling across a coastal plain catena

Gacengo, Catherine N. Wood, C. W. Shaw, Joey N., January 2008 (has links) (PDF)
Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Includes bibliographical references (p. 126-136).
68

Climate change and transportation challenges and opportunities /

Schmidt, Nicholas Andrew January 2008 (has links)
Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Meyer, Michael; Committee Member: Garrow, Laurie; Committee Member: Guensler, Randall
69

Using enzymes to link soil structure and microbial community function in a prairie chronosequence

Fansler, Sarah J., January 2004 (has links) (PDF)
Thesis (M.S. in Soil Science)--Washington State University. / Includes bibliographical references.
70

Policy options to enhance technology diffusion : modeling the greenhouse gas reduction potential of solid-state lighting /

Slocum, Amanda K. January 2004 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2004. / Typescript. Includes bibliographical references (leaves 123-127).

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