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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

Potential Urban Forest Carbon Sequestration and Storage Capacities in Burnside Industrial Park, Nova Scotia

Walsh, Alison 13 April 2012 (has links)
Urban and industrial settings represent potential areas for increased carbon (C) sequestration and storage through intensified tree growth. Consisting of an estimated 1270 ha of land once entirely forested, Burnside Industrial Park (BIP) in Dartmouth, Nova Scotia. Our study examines the degree to which intensified urban tree planting within the BIP ecosystem could enhance C sequestration and storage. This was achieved by conducting a geospatial analysis in combination with construction of a C model. Three scenarios urban forest development were examined. If all potential planting spots are filled with trees by 2020, an estimated 26,368 tC, at a sequestration rate of 635 tC/yr, could be achieved by 2050. Next, we explored the challenges and opportunities associated with pursuing C offset markets as a means for funding urban forest development within BIP. A basic framework from which a community?based C offset market could potentially be established was recommended.
82

Soil carbon and nitrogen dynamics along replicated chronosequences of abandoned agricultural lands in southeastern Ontario

Foote, Robyn Louise 20 December 2007 (has links)
Widespread abandonment of agricultural land has occurred in northeastern North America over the past two centuries. Soil carbon often increases as sites naturally regenerate towards perennial grasslands or forests. Understanding the large-scale controls on the potential and rate of soil carbon sequestration is necessary in order to evaluate the significance of this sink to the global carbon cycle. Furthermore, we need to understand the key roles soil microorganisms play in regulating ecosystem processes through their control over soil carbon and nitrogen dynamics. Such studies are rare at the century long time scale of temperate forest succession. Additionally, research has taken place primarily on productive agricultural soils, while abandonment is more common on marginal agricultural soils. We characterized patterns of total and labile soil carbon and nitrogen and microbial dynamics in mature forest and adjacent agricultural field sites, and in replicated chronosequences of forest successional sites on marginal soils of southeastern Ontario, Canada. Total soil carbon was significantly depleted in the top 10 cm of current agricultural fields as compared to forest sites and increased at a rate of 10 g C m-2 yr-1 across our 100-year chronosequences. There was no difference in carbon loss or accumulation over time in three soil types differing in texture and parent material, suggesting that time since abandonment is more important than soil type in determining carbon accumulation within this climatic region. In contrast, free-light fraction carbon did not increase over time and thus most carbon accumulated in pools with slower turnover times. Soil microbial biomass carbon and nitrogen increased significantly following abandonment and our results strongly suggest that microbial growth during all phases of succession was limited by carbon supply. In contrast, net nitrogen mineralization and nitrification rates during mid-summer did not change consistently over the first 100 years following agricultural abandonment. Therefore, inorganic nitrogen supply rates into the plant available pool were similar across the entire successional sequence. Together, the results of these two studies demonstrate the potential for carbon sequestration in abandoned agricultural soils across this climatic region and highlight the importance of plant-soil interactions for understanding carbon cycling during ecosystem development. / Thesis (Master, Biology) -- Queen's University, 2007-12-14 10:04:57.395
83

CO2 storage in a Devonian carbonate system, Fort Nelson British Columbia

Crockford, Peter W. 19 March 2012 (has links)
This study geochemically characterized a proposed Carbon Capture and Storage project in northeast British Columbia, and presents new dissolution kinetics data for the proposed saline aquifer storage reservoir, the Keg River Formation. The Keg River Formation is a carbonate reservoir (89-93% Dolomite, 5-8% Calcite) at approximately 2200 m depth, at a pressure of 190 bar, and temperature of 105 °C. The Keg River brine is composed of Na, Cl, Ca, K, Mg, S, Si, and HCO3 and is of approximately 0.4 M ionic strength. Fluid analysis found the Keg River brine to be relatively fresh compared with waters of the Keg River formation in Alberta, and to also be distinct from waters in overlying units. These findings along with the physical conditions of the reservoir make the Keg River Formation a strong candidate for CO2 storage. Further work measured the dissolution rates of Keg River rock that will occur within the Keg River formation. This was performed in a new experimental apparatus at 105 °C, and 50 bar pCO2 with brine and rock sampled directly from the reservoir. Dissolution rate constants (mol!m-2s-1) for Keg River rock were found to be Log KMg 9.80 ±.02 and Log KCa -9.29 ±.04 for the Keg River formation. These values were found to be significantly lower compared to rate constants generated from experiments involving synthetic brines with values of Log KMg -9.43 ±.09, and Log KCa -9.23 ±.21. Differences in rates were posited as due to influences of other element interactions with the >MgOH hydration site, which was tested through experiments with brines spiked with SrCl2 and ZnCl2. Results for the SrCl2 spiked solution showed little impact on dissolution rates with rate constants of Log KMg -9.43 ±.09, and Log KCa -9.15 ±.21, however the ZnCl2 spiked solution did show some inhibition with rate constants of Log KMg -9.67 ±.04, and Log KCa -9.30 ±.04. Rate constants generated in this work are among the first presented which can actually be tested by full-scale injection of CO2. / Graduate
84

Geological evaluation of the Eocene Latrobe Group in the offshore Gippsland Basin for CO₂ geosequestration.

Root, Robert January 2007 (has links)
Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / This study area for this research is characterised by a regional anticline plunging to the east-south-east with large-scale internal architecture comprising transgressive, retrogradationally stacked stratigraphy that dips gently landward and is unconformably truncated by overlying sealing units. The primary reservoir/aquifer targets for CO₂ injection are palaeo-shoreline parallel nearshore sandstone bodies characterised by high porosity and permeability and good interconnectivity. The key regional sealing unit is the Lakes Entrance Formation, which consists of mudstone and marl capable of sealing large columns of CO₂. The proposed stategy for CO₂ geosequestration is to inject CO₂ outside four-way structural closure to allow up-dip fluid migration to the north then west governed by the structure of regional sealing units. Probabilistic estimates of CO₂ capacity utilising the proposed strategy indicate that 1395-2575 Mtonnes could be sequestered. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1281480 / Thesis (Ph.D.) -- University of Adelaide, Australian School of Petroleum, 2007
85

Geological evaluation of the Eocene Latrobe Group in the offshore Gippsland Basin for CO₂ geosequestration.

Root, Robert January 2007 (has links)
Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / This study area for this research is characterised by a regional anticline plunging to the east-south-east with large-scale internal architecture comprising transgressive, retrogradationally stacked stratigraphy that dips gently landward and is unconformably truncated by overlying sealing units. The primary reservoir/aquifer targets for CO₂ injection are palaeo-shoreline parallel nearshore sandstone bodies characterised by high porosity and permeability and good interconnectivity. The key regional sealing unit is the Lakes Entrance Formation, which consists of mudstone and marl capable of sealing large columns of CO₂. The proposed stategy for CO₂ geosequestration is to inject CO₂ outside four-way structural closure to allow up-dip fluid migration to the north then west governed by the structure of regional sealing units. Probabilistic estimates of CO₂ capacity utilising the proposed strategy indicate that 1395-2575 Mtonnes could be sequestered. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1281480 / Thesis (Ph.D.) -- University of Adelaide, Australian School of Petroleum, 2007
86

An evaluation of mineral carbonation as a method for sequestration of carbon dioxide

Rock, Robert. January 2007 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen viewed (2/14/2008). Includes bibliographical references (leaves 34-40).
87

Biological sequestration of carbon dioxide

Bagga, Rajinder S. January 2000 (has links)
Thesis (M.S.)--Ohio University, August, 2000. / Title from PDF t.p.
88

Geological sequestration of carbon dioxide by hydrous carbonate formation in steelmaking slag

Rawlins, Charles Henry, January 2008 (has links) (PDF)
Thesis (Ph. D.)--Missouri University of Science and Technology, 2008. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 18, 2008) Includes bibliographical references.
89

Biennial seasonal burning and hardwood control effects on the carbon sequestration in a natural longleaf pine ecosystem

Thapa, Ram, Gjerstad, Dean H. January 2008 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographic references (p.64-82).
90

Reservoir simulation studies for coupled CO₂ sequestration and enhanced oil recovery

Ghomian, Yousef, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

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