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Cities are considered to be a major cause of climate change, as a result of city functions, which require energy and emit large quantities of Greenhouse Gases (GHGs). Therefore, cities are being targeted globally as key areas for climate change mitigation. In order to mitigate the impacts of climate change, it is important for policy makers to be able to understand the implications of possible future policy decisions and development plans on emissions. One possible way of developing forecasts is through emissions scenarios, which allow for the development of a series of forecasts based on changes in the drivers of emissions. The city of Durban is a developing city, which aims to promote economic development; however, this development would increase the demand for energy and therefore impact on the GHG emissions in the city. The aim of this study is to develop a number of GHG emissions scenarios that illustrate the implications of various development paths for the city. The methodology applied involved first identifying the gaps in existing GHG inventories for Durban and the data required to close these gaps. The data was input into the Long-range Energy Alternatives Planning (LEAP) tool, which is a physical accounting and simulation tool that allows for the creation of scenarios. Five scenarios were created to illustrate different ways in which the city might develop which are the Growth without Constraints (GWC) Scenario, the Business as Usual (BAU) Scenario, the Natural Transition City, the Slow Go City and the Low Carbon City. Lastly, a sixth scenario, the Required by Science (RBS), was not modelled but created to illustrate what would be required if Durban followed the Intergovernmental Panel on Climate Change (IPCC) stabilisation guideline of a reduction of 60% - 80% of 1990 levels by 2100. Thereafter the IPCC scenarios were downscaled from a national level to a local level using a linear downscaling methodology, in order to illustrate the implications of global development paths on the city. The different development paths had a range of impacts on emissions. Rapid economic growth, with no climate change mitigation in the GWC Scenario, results in a 6.3 times increase in emissions from the base year to 2050. If the city continues with its current policies and strategies as in the BAU Scenario, emissions will increase 3.5 times from the base year. If there is a transition to a post-industrial society, with no climate change mitigation, emissions will increase 3 fold from 2005 to 2050. The National Transition Scenario illustrated that if Durban moves towards a service sector economy, which are predominantly low carbon sector, with no climate change mitigation, emissions will still increase 3.15 times the 2005 levels. If the city is slow to respond to climate change as in the Slow Go City, emissions will increase 2.5 times from the base year. A shift in the structure of the economy and an increase in the use of renewable energy and energy efficiency (i.e. a Low Carbon City) results in reduction in emissions of 1% from 2005. These were compared to the IPCC downscaled scenarios, which followed a similar pattern. The scenarios are comparable to developing city scenarios, but illustrate that the city is lagging behind developed cities. In order to make an impact in the reduction of emissions, it is essential for the city to target the commercial and industrial sector, which is the sector that emits the highest GHG emissions. However all these scenarios are still insufficient for achieving the RBS emissions target of a 60-80% reduction from 1990 levels. Achieving this reduction would require more than a 50% improvement in energy efficiency, structural change in the economy to low energy intensive sectors and a 20% contribution of renewable energy to total energy supply. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2010.

A study was conducted in 2004 and 2005 to determine the effect of liquid hog manure fertilization on greenhouse gas emissions from the surface of a grassland pasture in south-eastern Manitoba. The objectives of this research were to determine the effects of manure application, itstiming and soil moisture on greenhouse gas emissions from pasture soil, cattle dung and urine patches. Nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) emissions were determined from grassland soil surface, and from cattle dung and artificial urine patches. Liquid hog manure treatments were no manure (Control); 153 kg ha-1 of available-nitrogen (N) (two year average) in spring (Spring); and 149 kg ha-1 as half-rate applications in fall and spring (Split). Four field experiments were conducted on grassland plots. The static-vented chamber technique was used to estimate gas emission rates. Two of the experiments focused on the effects of manure application timing and soil moisture on greenhouse gas emissions from the grassland soil surface. The other two experiments focused on the effects of manure application and soil moisture on greenhouse gas emissions from cattle dung and artificial urine patches. Fresh cattle dung was collected from steers grazing adjacent pastures receiving the same three manure treatments. Artificial cattle urine treatments were generated by converting blood urea concentrations of the steers into urine-N concentrations. Manure application increased (P≤0.01) cumulative N2O emissions from the grassland soil surface with Control, Split and Spring treatments averaging 7, 43 and 120 mg N2O-N m-2, respectively. Of the two manure treatments, the Spring treatment emitted higher (P≤0.10) N2O emissions than the Split treatment. Soil moisture was a major factor influencing the quantity and type of greenhouse gas emissions, with saturated areas emitting CH4 during warm periods, whereas drier areas emitted N2O. Nitrous oxide emissions from these dry areas were higher in manure-treated plots. Spring application increased root density by 45% in the top 5 cm of soil compared to the Control. An increase in soil organic carbon with root density may offset any increase in greenhouse gas emissions caused by manure treatment. Cattle dung from Split and Spring treatments had higher cumulative N2O emissions (30 and 82 mg N2O-N m-2, respectively) compared to dung from Control pastures (6 mg N2O-N m-2) over two study years. Dung from the Spring treatment emitted more N2O (P≤0.01) than the other two treatments. All cattle dung patches emitted CH4 after deposition though unaffected by manure treatment. Artificial urine having highest N concentration had greater (P≤0.05) cumulative N2O emissions (690 mg N2O-N m-2) than urine with the lowest N concentration (170 mg N2O-N m-2). Drier soil locations emitted more N2O from cattle dung and artificial urine patches than wetter areas. This study demonstrated that Split application of liquid hog manure to grassland emitted less N2O than a complete application in spring. Moisture greatly affected the location of N2O and CH4 emissions. Drier areas emitted more N2O than wetter ones. Particularly, the findings indicate a need to assess grassland on periodically saturated soils as sources rather than sinks for CH4. Application of manure increased greenhouse gas emissions from cattle dung and urine patches with urine potentially having the greatest impact because of their higher emissions of N2O. An increase in root growth seems to offset greenhouse gas emissions from manure application.

Reliable determinations of ecosystem scale fluxes of net carbon (C) and greenhouse gases for northern peatland ecosystems are of great value to determine the impact of soil warming and altered precipitation on emissions. Additionally, few studies have been performed which measure the C fluxes, particularly methane flux (FCH4), during the spring melt and fall freeze up periods, therefore making it difficult to provide adequate annual C estimates from northern peatland ecosystems. This study aimed to determine ecosystem scale FCH4 from a eutrophic Subarctic fen at Churchill, Manitoba (58°45'N 94°4'W), to understand (a) seasonal trends over two consecutive growing seasons,(b) if over-winter stored CH4 was released as a pulse during the spring-melt period, and (c) soil temperature - FCH4 relations for modelling FCH4 over the spring-melt period. An ecosystem scale methane (CH4) and carbon dioxide (CO2) flux measurement system using the eddy covariance (EC) technique was used from late-June to mid-October of 2008 and early-June to late-September of 2009, with focus on the spring-melt period of late-May to mid-July of 2009. The EC flux measurement system consisted of a closed-path RMT-200 Fast Methane Analyzer (Los Gatos Research Inc.) along with a LI-7500 open-path CO2/H2O gas analyzer (LI-COR Biosci.) and a CSAT3 3-dimensional sonic anemometer (Campbell Sci.). The system was powered by a combination of wind, solar, and gas electric generation. The EC flux measurement system provided seasonal FCH4 values of 0 – 90 nmol CH4 m-2 s-1, similar to previous studies in Subarctic and Arctic peatlands which incorporated the EC technique. A melt period CH4 emission burst was not observed, rather a gradual increase in emission over the spring period. Modelled FCH4 using a temperature-response curve relationship with soil temperature at 5 cm depth over the spring-melt period (May 30 – July 19, 2009) showed the fen to be a net source of CH4, of 1.4 mmol m-2 CO2 equivalent.

Agriculture contributes significantly to national and global greenhouse gas (GHG) inventories but there is considerable control over management decisions and changes in production methods could lead to a significant reduction and possible mitigation of emissions from the sector. For example, conservation tillage practices have been suggested as a method of sequestering atmospheric carbon dioxide (CO2), however, many questions remain unanswered regarding the short-term efficacy of the production method and knowledge gaps exist regarding possible interactions with essential nutrient cycles, and the production of non-CO2 GHGs, such as nitrous oxide (N2O). Between autumn 2005 and 2009, a micrometeorological flux system was used to determine net CO2 and N2O exchange from an annual cropping system situated on clay soil in the Red River Valley of southern Manitoba. Four plots (4-ha each) were independently evaluated and planted to corn in 2006 and faba bean in 2007; in 2008, two spring wheat plots were monitored. As well, during the non-growing season in 2006-2007 following corn harvest, a second micrometeorological flux system capable of simultaneously measuring stable C isotopologue (12CO2 and 13CO2) fluxes was operated at the site. Tillage intensity and crop management practices were examined for their influence on GHG emissions. Significant inter-annual variability in CO2 and N2O fluxes as a function of crop and related management activities was observed. Tillage intensity did not affect GHG emissions from the site. After accounting for harvest removals, the net ecosystem C budgets were 510 (source), 3140 (source) and -480 (sink) kg C/ha/year for the three respective crop years, summing to a three-year loss of 3170 kg C/ha. Stable C isotope flux measurements during the non-growing season following corn harvest indicated that approximately 70 % and 20 – 30 % of the total respiration flux originated from crop residue C during the fall of 2006 and spring of 2007, respectively. The N2O emissions at the site further exacerbated the net global warming potential of this annual agroecosystem.

The main goal of the thesis is to develop a monitoring instrument for climate policy that is based on the Kyoto Protocol and the IPCC guidelines. The instrument developed is based on a "Full Carbon Accounting" approach which takes into account the carbon flows of the biosphere as well as those related to society's metabolism. Conceptually the analysis is based on the epistemological concept of society nature interaction comprising society's metabolism and colonisation of nature as main starting points. This leads to the empirical concept of material flow analysis. The thesis quantifies the carbon flows and the related uncertainties of the Austrian economy for 1990 for selected areas in a consistent way. The thesis also tries to build up a framework for system of indicators that would allow evaluating climate policy. (author´s abstract)

Irrigated agriculture in the Canadian Prairies is in a position to play a prominent role in addressing global food demands imposed by a growing world population. Particularly within Saskatchewan there is potential to see large increases in the number of irrigated hectares, due to the large irrigable land base and supply of freshwater resources. Yet, how this increase will influence the agricultural greenhouse gas (GHG) balance is not well understood. Through the quantification and comparison of GHG emissions from a typical irrigated and dryland cropping system in Saskatchewan, this research aimed to better understand the role of irrigated agriculture on GHG dynamics in this region. A field-scale analysis of irrigated soil conditions and resulting soil greenhouse gas emissions identified that soil N availability was likely the dominant factor influencing soil N2O emissions from irrigated systems. Soil moisture was also a key factor in soil GHG fluxes, governing seasonal CH4 uptake and episodic N2O and CO2 emissions. The development of system-specific GHG budgets—incorporating on-site GHG sources and sinks—identified electricity as irrigated cropping’s largest contributor of global warming potential (GWP). Emissions from soil and diesel-combustion sources were less intensive under irrigated production; yet overall greenhouse gas intensity (GHGI) was greater from irrigated cropping. This research provides a first look into GHG dynamics from irrigated agriculture in Saskatchewan and identifies areas for potential mitigation as irrigated crop production expands in the Province.

Economic and environmental objectives are traditionally seen as mutually exclusive, especially in terms of higher economic growth rates that are coupled with higher greenhouse gas emissions. The first aim of this study is to find a possible creative solution, in which higher economic growth can be coupled with lower greenhouse gas emissions, also known as low-carbon growth. The literature review shows that the economic growth aspect of low-carbon growth can be achieved by increasing exports. The other part of low-carbon growth, namely lower greenhouse gas intensity, can be achieved by diffusing low-carbon technologies (or environmental goods). The World Trade Organisation also encouraged the liberalisation of environmental goods. Therefore, low-carbon growth could be achieved by promoting the production and exports of low-carbon environmental goods. Although the World Trade Organisations has encouraged the liberation of environmental goods, there is no official list of environmental goods. Therefore, the second aim of this study is to derive a list of low-carbon environmental goods from existing lists of environmental goods. Thirty-nine lowcarbon environmental goods are identified for the purpose of this study. The Decision Support Model (DSM) is used to identify realistic export opportunities for these environmental goods. These low-carbon environmental goods were ranked based on three criteria: i) their potential environmental benefits, ii) South Africa’s capacity to produce these goods, and iii) their potential economic benefits. The five low-carbon environmental goods that ranked the highest are photosensitive semiconductors (HS-6: 854140), towers and lattice masts (HS-6: 730820), electrical control and distribution boards smaller than 1kV (HS-6: 853710), gearing, ball screws, speed changers, torque converter (HS-6: 848340), and static converters (HS-6: 850440). The exact environmental uses, producers, intensive and extensive export opportunities of the top five goods were discussed. The best overall intensive export opportunities according to potential export value are HS-6: 854140; photosensitive semiconductors (USD 922,362,000) to Germany and HS-6: 853710; electrical control and distribution boards smaller than 1kV, to the United States (USD 838,671,000). The best overall extensive export opportunities according to their potential export value are HS-6: 854140; photosensitive semiconductors to China (USD 953,255,000) and HS-6: 854140; photosensitive semiconductors to Hong Kong (USD 363,505,000). The results of this study will enable policy-makers to make optimal decisions regarding which environmental goods to produce and export. / Thesis (MCom (Economics))--North-West University, Potchefstroom Campus, 2013.

Economic and environmental objectives are traditionally seen as mutually exclusive, especially in terms of higher economic growth rates that are coupled with higher greenhouse gas emissions. The first aim of this study is to find a possible creative solution, in which higher economic growth can be coupled with lower greenhouse gas emissions, also known as low-carbon growth. The literature review shows that the economic growth aspect of low-carbon growth can be achieved by increasing exports. The other part of low-carbon growth, namely lower greenhouse gas intensity, can be achieved by diffusing low-carbon technologies (or environmental goods). The World Trade Organisation also encouraged the liberalisation of environmental goods. Therefore, low-carbon growth could be achieved by promoting the production and exports of low-carbon environmental goods. Although the World Trade Organisations has encouraged the liberation of environmental goods, there is no official list of environmental goods. Therefore, the second aim of this study is to derive a list of low-carbon environmental goods from existing lists of environmental goods. Thirty-nine lowcarbon environmental goods are identified for the purpose of this study. The Decision Support Model (DSM) is used to identify realistic export opportunities for these environmental goods. These low-carbon environmental goods were ranked based on three criteria: i) their potential environmental benefits, ii) South Africa’s capacity to produce these goods, and iii) their potential economic benefits. The five low-carbon environmental goods that ranked the highest are photosensitive semiconductors (HS-6: 854140), towers and lattice masts (HS-6: 730820), electrical control and distribution boards smaller than 1kV (HS-6: 853710), gearing, ball screws, speed changers, torque converter (HS-6: 848340), and static converters (HS-6: 850440). The exact environmental uses, producers, intensive and extensive export opportunities of the top five goods were discussed. The best overall intensive export opportunities according to potential export value are HS-6: 854140; photosensitive semiconductors (USD 922,362,000) to Germany and HS-6: 853710; electrical control and distribution boards smaller than 1kV, to the United States (USD 838,671,000). The best overall extensive export opportunities according to their potential export value are HS-6: 854140; photosensitive semiconductors to China (USD 953,255,000) and HS-6: 854140; photosensitive semiconductors to Hong Kong (USD 363,505,000). The results of this study will enable policy-makers to make optimal decisions regarding which environmental goods to produce and export. / Thesis (MCom (Economics))--North-West University, Potchefstroom Campus, 2013.

A study was conducted in 2004 and 2005 to determine the effect of liquid hog manure fertilization on greenhouse gas emissions from the surface of a grassland pasture in south-eastern Manitoba. The objectives of this research were to determine the effects of manure application, itstiming and soil moisture on greenhouse gas emissions from pasture soil, cattle dung and urine patches. Nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) emissions were determined from grassland soil surface, and from cattle dung and artificial urine patches. Liquid hog manure treatments were no manure (Control); 153 kg ha-1 of available-nitrogen (N) (two year average) in spring (Spring); and 149 kg ha-1 as half-rate applications in fall and spring (Split). Four field experiments were conducted on grassland plots. The static-vented chamber technique was used to estimate gas emission rates. Two of the experiments focused on the effects of manure application timing and soil moisture on greenhouse gas emissions from the grassland soil surface. The other two experiments focused on the effects of manure application and soil moisture on greenhouse gas emissions from cattle dung and artificial urine patches. Fresh cattle dung was collected from steers grazing adjacent pastures receiving the same three manure treatments. Artificial cattle urine treatments were generated by converting blood urea concentrations of the steers into urine-N concentrations. Manure application increased (P≤0.01) cumulative N2O emissions from the grassland soil surface with Control, Split and Spring treatments averaging 7, 43 and 120 mg N2O-N m-2, respectively. Of the two manure treatments, the Spring treatment emitted higher (P≤0.10) N2O emissions than the Split treatment. Soil moisture was a major factor influencing the quantity and type of greenhouse gas emissions, with saturated areas emitting CH4 during warm periods, whereas drier areas emitted N2O. Nitrous oxide emissions from these dry areas were higher in manure-treated plots. Spring application increased root density by 45% in the top 5 cm of soil compared to the Control. An increase in soil organic carbon with root density may offset any increase in greenhouse gas emissions caused by manure treatment. Cattle dung from Split and Spring treatments had higher cumulative N2O emissions (30 and 82 mg N2O-N m-2, respectively) compared to dung from Control pastures (6 mg N2O-N m-2) over two study years. Dung from the Spring treatment emitted more N2O (P≤0.01) than the other two treatments. All cattle dung patches emitted CH4 after deposition though unaffected by manure treatment. Artificial urine having highest N concentration had greater (P≤0.05) cumulative N2O emissions (690 mg N2O-N m-2) than urine with the lowest N concentration (170 mg N2O-N m-2). Drier soil locations emitted more N2O from cattle dung and artificial urine patches than wetter areas. This study demonstrated that Split application of liquid hog manure to grassland emitted less N2O than a complete application in spring. Moisture greatly affected the location of N2O and CH4 emissions. Drier areas emitted more N2O than wetter ones. Particularly, the findings indicate a need to assess grassland on periodically saturated soils as sources rather than sinks for CH4. Application of manure increased greenhouse gas emissions from cattle dung and urine patches with urine potentially having the greatest impact because of their higher emissions of N2O. An increase in root growth seems to offset greenhouse gas emissions from manure application.