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Greenhouse gas emissions from Pacific Northwest forestry operations : implications for forest management /Hall, Edith Carol Sonne. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 128-139).
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Quantification of greenhouse gas fluxes from soil in agricultural fieldsNkongolo, Nsalambi Vakanda January 2010 (has links)
Field studies were conducted at Lincoln University of Missouri (USA) and Hokkaido University (Japan) to: (i) study the relationships between greenhouse gases emissions and soil properties, (ii) assess the influence of agricultural practices on greenhouse gas fluxes and soil properties and (iii) improve the quantification of greenhouse gases from soil in agricultural fields using geospatial technologies. Results showed that besides soil temperature (T), soil thermal properties such as thermal conductivity (K), resistivity (R) and diffusivity (D) and soil pore spaces indices such as the pore tortuosity factor and the relative gas diffusion coefficient (Ds/Do) are controlling factors for greenhouse gases emissions. Soil thermal properties correlated with greenhouse gases emissions when soil temperature could not. The study has found that predicted Ds/Do and correlate with greenhouse gas fluxes even when the air-filled porosity and the total porosity from which they are predicted did not. We have also showed that Ds/Do and can be predicted quickly from routine measurements of soil water and air and existing diffusivity models found in the literature. Agricultural practices do seriously impact greenhouse gases emissions as showed by the effect of mechanized tillage operations on soil physical properties and greenhouse gas fluxes in a corn and soybean fields. In fact, our results showed that tractor compaction increased soil resistance to penetration, water, bulk density and pore tortuosity while reducing air-filled porosity, total pore space and the soil gas diffusion coefficient. Changes in soil properties resulted in increased CO2, NO and N2O emissions. Finally, our results also confirmed that greenhouse gas fluxes vary tremendously in space and time. As estimates of greenhouse gas emissions are influenced by the data processing approach, differences between the different calculation approaches leads to uncertainty. Thus, techniques for developing better estimates are needed. We have showed that Geographic Information Systems (GIS), Global Positioning System (GPS), computer mapping and geo-statistics are technologies that can be used to better understand systems containing large amounts of spatial and temporal variability. Our GIS-based approach for quantifying CO2, CH4 and N2O fluxes from soil in agricultural fields showed that estimating (extrapolating) total greenhouse gas fluxes using the “standard” approach – multiplying the average flux value by the total field area – results in biased predictions of field total greenhouse gases emissions. In contrast, the GIS-based approach we developed produces an interpolated map portraying the spatial distribution of gas fluxes across the field from point measurements and later process the interpolated map produced to determine flux zones. Furthermore, processing, classification and modeling enables the computation of field total fluxes as the sum of fluxes in different zones, therefore taking into account the spatial variability of greenhouse gas fluxes.
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Nitrous oxide emissions from a Northern Great Plains soil as influenced by nitrogen fertilization and cropping systemsDusenbury, Matthew Paul. January 2006 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2006. / Typescript. Chairperson, Graduate Committee: Richard E. Engel. Includes bibliographical references (leaves 73-84).
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COMPARATIVE ECONOMIC AND ENVIRONMENTAL TRADE-OFF ANALYSIS FOR MANITOBA COW-CALF PRODUCTION2016 January 1900 (has links)
There were 12.5 million head of cattle in all of Canada as of January 1st, 2012, of which 7.4 million were on cow-calf farms. Of this population, 1.2 million head of cattle were in Manitoba, and within that, 880 thousand were on cow-calf farms. Canadian and Manitoba beef producers have experienced significant volatility in the cattle market. This is partly as a result of loss of exports of cattle to the United States, first due to occurrence of the Bovine spongiform encephalopathy (BSE) Crisis, and then through the Country of Origin Labelling (COOL) legislation developed in the United States.
While the beef industry has endured market fluctuations, the North American cattle herd has also been responsible for greenhouse gas (GHG) emissions, through enteric fermentation within their digestive tracks, storage of manure on farms, through the spread of manure on crop fields, and through the production of feed for cattle. Of the total Canadian GHG emissions, agriculture contributed 8 percent in 2013. For the same year, within the total agricultural GHG emissions, cattle and sheep production resulted in 40 percent of methane emissions, and 90 percent of nitrous oxide emissions, both expressed in carbon dioxide equivalent. Regionally, the share of agricultural GHG emissions in Manitoba make up a larger proportion of total provincial GHG emissions, at 31 percent of 21.4 Mt CO2e, as the province has fewer emissions from transportation or stationary combustion..
The confluence of low profitability and larger amounts of GHG emission (relative to other provinces) has led to some discussion on adopting measures to reduce these emissions. This has caused some stress in the beef industry, as some of these proposed solutions could lead to further loss in profits. An European study of the beef sector has investigated the impact of some policy instruments, such as emission taxes, and has suggested that while such measures are effective, they would also be financially restrictive to beef producers, or result in high administrative costs for governments (Neufeldt and Schäfer 2008). However, these measures might be unnecessary, as the Manitoba Beef Producers (2011) have indicated that the Manitoba beef producers are willing to undertake alternate management practices to benefit environmental causes if they do not negatively affect their profitability or livelihoods. Therefore, providing methods that lead to lower GHG emissions while providing high levels of profitability, or maintaining current levels of profitability would be considered a welcome set of information for the Manitoba beef cattle producers (and likely producers in other provinces).
In order to understand GHG emissions on beef farms, a Canada-wide survey was undertaken in 2012. Financial support for this survey was provided by a variety of interested parties including the University of Manitoba, Alberta Agriculture and Rural Development, the BC Ministry of Agriculture, Manitoba Agriculture Food and Rural Initiatives, and Agriculture and Agri-Food Canada, with the support of the Beef Cattle Research Council. Researcher Aklilu Alemu from the University of Manitoba used principle component analysis and cluster analysis to create eight clusters of representative farms across the country. Of the eight Canadian clusters, only four clusters had a population greater than one in Manitoba. The centroid from each cluster was chosen as a representative farm for this study. Estimates of GHG emissions from each farm were then determined using Holos, a GHG emission model developed by the Government of Canada.
To compare GHG emissions against profitability on a farm, this study evaluated revenues and costs of four Manitoba farms (One each from the four clusters). The revenues included the sale of weaned calves and cull cows, as well as the sale of unused feed and non-feed grain. The costs for the whole farm included the cost to grow feed for the cattle, while operating costs for each of these farms included veterinary, transportation, manure removal, and utility costs. The fixed costs (related to farm structures and machinery) were comprised of depreciation and interest costs. In order to understand the profitability of the beef enterprise as well as the whole farm, the costs and revenues were estimated at three levels: beef enterprise, the whole farm, and the family level.
With regards to the beef enterprise, the farm in Cluster Four had the highest level of profitability, at $0.05 per pound of live animal weight sold [or on a per pound sold (PPS) basis]. At the same time, this farm was also able to achieve the lowest GHG emissions, at 2.20 lbs. PPS basis measured in Carbon Dioxide Equivalent (CO2e). The farm with the second lowest level of GHG emissions (9.68 lbs. CO2e on a PPS basis) were estimated for the Cluster Six Farm, which also had the second highest profitability ($0.01 on a PPS basis).
When measured at the beef enterprise level, several farms had net GHG emissions. Higher farm level profitability was contributed by a high weaning weight, the lower cost to produce feed, and the strategic purchase of machinery to feed each herd. Lower emissions were noted on farms with tame pastureland and greater amounts of forage with alfalfa.
Comparing profits and GHG emissions at the whole farm level showed different results. The Cluster Seven farm had the highest level of profitability ($1.53 on a PPS basis) while it was also the largest contributor to GHG emissions (12.16 lbs. CO2e on a PPS basis). Cluster Six farm was the second largest contributor to GHG emissions (7.54 lbs. CO2e on a PPS basis), but also created the least profit on its farm ($0.13 on a PPS basis). The farms with net sequestration (i.e., GHG emissions were negative) were Cluster Four and Cluster One farms. Both of these farms were both able to create profitability. On a PPS basis, Cluster Four farm had the second highest profitability ($0.80 on a PPS Basis) and sequestered second greatest emissions (2.38 lbs CO2e on a PPS basis). Cluster One farm had the second lowest profitability ($0.33 on a PPS basis) and sequestered the most GHGs (30.17 lbs CO2e on a PPS basis). Increases in the level of net sequestration were due to tame pastureland and large amounts of unused hay growth which included legumes such as alfalfa. Increases in profitability were due to the sale of non-feed grains, feed grains or hay, as well as other factors noted above regarding the beef enterprise.
These findings suggest that Manitoba beef producers could provide greater profitability and lower GHG emissions if they increased their weaning weights, increased the size of their herds, invested in tame pastureland when possible, and cut their forage several times throughout the growing season.
Since this study is based on a single farm from four clusters, additional research is necessary. This may include studying several farms in each cluster in order to determine variability in long-term feed production, as well as in costs and revenues.
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Livscykelanalys av granulärt svavel respektive torv : Vilken produkt genererar minst utsläpp av växthusgaser?Reinklou, Johan January 2016 (has links)
The purpose of this report was to investigate which of the two products peat and granular sulphur that generates the least greenhouse gas emissions. The study was performed by doing a comparative Life Cycle Assessment (LCA) on the two different products. To perform the LCA, a standard from the Swedish Standards Institute was used. Data to put into the calculation was obtained from both Umeå Energi, their contractors and different internet-sources. The data was then multiplied with specific emission factors to get the total emission of greenhouse gases, expressed as carbon dioxide equivalents. Since peat is considered both a fossil energy source and a renewable energy source two calculations were made in the case of peat production. Results showed that granular sulphur generated the least emissions (23.0), peat classified as a renewable energy source second most emissions (71.5) and peat classified as a fossil energy source by far the most emissions (978.2). The conclusion to be made by this study is that if only the emission of greenhouse gases are important when choosing a product, granular sulphur should be used. Key words: peat, greenhouse gases, LCA, sulphur.
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The effect of climate on decomposition in forest ecosystemsChadwick, David R. January 1995 (has links)
No description available.
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Development of an analytical system for the determination of highly fluorinated compounds in air samplesGreally, Brian Roger January 2000 (has links)
No description available.
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Global warming and changing patterns of horticultural production in the United KingdomHolloway, Lewis E. January 1995 (has links)
No description available.
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Quantifying Energy Consumption and Carbon Dioxide Equivalent Generation in Typical Roadway Construction Projects2013 August 1900 (has links)
All roadway agencies monitor and maintain their infrastructure as it deteriorates over time. Agencies allocate the money that they have for maintenance, rehabilitation and reconstruction operations across their entire network. Regular and timely maintenance and rehabilitation treatments can postpone the need for reconstruction on a roadway.
The need for infrastructure sustainability has been brought to the forefront of society and has become an important part of any public agency’s decision making processes. To achieve sustainable roadways social, economic and environmental benefits must be achieved while maintaining technically sound solutions. By considering the amount of energy that is consumed and the amount of greenhouse gas (GHG) emissions generated through various roadway treatments, sustainability can be brought into the decision making process.
The objective of this research was to develop a probabilistic model that quantifies the amount of energy that is consumed and carbon dioxide equivalents (CO2e) generated for typical roadway construction, maintenance, rehabilitation and reconstruction projects in Saskatchewan and Alberta.
The model constructed within this work was divided into three sub-models: 1) material production, 2) equipment usage and 3) material transport. For every variable that was required to be entered into each sub-model, a low, average or most likely and high value was determined. By using a range of input values the uncertainty of the values entered was incorporated and sensitive parameters were identified.
A base case study of a one lane-kilometer (lane-km), 3,700 m2, section of rural roadway was analyzed. For the initial construction of a lane-km of traditional flexible pavement roadway it was determined that 1,870 GJ (giga joules) of energy is required. Based on an annual average amount of energy used per home in Saskatchewan, 126 GJ/year, 1,870 GJ would power approximately 15 homes for one year. Similarly it was determined that 152.4 tonnes (t) CO2e are emitted for the construction of a lane-km of traditional flexible pavement roadway. Based on an average CO2e generation value of 5.1 t per passenger vehicle per year the GHG emissions generated from the construction of a lane-km of roadway is equivalent to the GHG emissions released by approximately 30 passenger vehicles over one year. It was also determined that the volume of CO2e generated for initial construction compared to the volume of material in the roadway was a ratio of 30 to 1.
The base case study also reviewed various maintenance, rehabilitation and reconstruction treatments for the amount of energy consumed and GHG emissions generated for one lane-km. From the modeled values it was found that the order of energy consumed and CO2e generated from least to greatest for maintenance treatments is: fog seal, slurry seal, micro surfacing, single, double and triple chip seal and ultra thin overlay. For rehabilitation and reconstruction treatments the order of energy consumed and CO2e generation from least to greatest is: cold in-place recycling, mill and fill, full depth reclamation, remove and replace with recycled materials and remove and replace with virgin materials.
Through a sensitivity analysis of the input parameters, it was observed that for maintenance treatments the sensitive parameters were the equipment efficiency (EFE) value, the placement rate of the treatment, the aggregate application rate and the amount of asphalt binder included in the treatment. For rehabilitation and reconstruction treatments, the two most sensitive parameters were the asphalt concrete plant energy and the application rate of the Portland cement.
Further investigation into how each sub-model contributed to the overall amount of energy consumed and CO2e generated found the production of materials contributed the greatest to the overall values. When examining the production of each layer in a traditional flexible pavement roadway structure, the asphalt layers contributed the greatest to the energy consumed at 72.1 percent of all materials produced. The asphalt layers also contributed the greatest to the GHG emissions generated from the production of materials at 42.7 percent. Further breaking down the production of the asphalt layers, the energy requirements at the hot mix asphalt concrete plant account for 75.9 percent of the energy consumed and 52.0 percent of the CO2e generated for the production of the materials of the asphalt layers.
The cost of each treatment was reviewed based on the cost of diesel at $1.21/litre and the amount of energy consumed. The costs of energy for the maintenance treatments ranged from $174/lane-km for fog seal to $5,488/lane-km of the ultra thin overlay. The cold in-place recycling and mill and fill rehabilitation treatments had energy costs of $13,545 and $21,440/lane-km respectively. The costs of the energy consumed for the reconstruction treatments ranged from $21,710/lane-km for full depth reclamation and $71,164/lane-km for remove and replace with virgin materials. Based on a review of the City of Saskatoon’s 2012 proposed treatment plan for its roadway network the cost of energy was estimated at $1,232,000 for work on 93 lane-km of roadway.
The costs of GHG emissions were also determined based on the amount of CO2e generated and the value of one tonne of carbon on the voluntary carbon credit market at $6/tonne. The costs of carbon for the maintenance treatments ranged from $3/lane-km for fog seal to $64/lane-km for the ultra thin overlay. For the rehabilitation treatments the cost of carbon for the cold in-place recycling was $224/lane-km and $266/lane-km for the mill and fill treatment. The reconstruction treatments ranged from $524/lane-km for full depth reclamation and $1,062 for remove and replace with virgin materials.
Finally four field case studies were reviewed to determine the amount of energy consumed and GHG emissions generated through construction. The first was the reconstruction of Range Road 232, a rural roadway with virgin materials. The second was the reconstruction of Kenderdine Road with recycled materials. The energy consumed and GHG emissions generated for these construction projects are 1,917 and 1,146 GJ/lane-km, and 150.3 and 92.6 t CO2e/lane-km, respectively. The third case study further reviewed the use of warm mix asphalt concrete (WMAC) and the use of recycled asphalt pavement (RAP) in the Kenderdine Road pavement structure. This research determined that with the incorporation of WMAC and 10 percent RAP in the asphalt layers and with the use of recycled materials in the base layers the amount of energy consumed would be reduced by 31.8 percent and the GHG emissions reduced by 34.8 percent compared to a traditional virgin pavement structure. The final case study reviewed the City of Saskatoon’s 2012 proposed roadway restoration and reconstruction plan. From the model it was found that 38,281 GJ of energy was consumed and 2,617 t CO2e was generated.
This work shows that the probabilistic model developed in this research may be applied to a variety of roadway treatments from maintenance to reconstruction in urban and rural applications. With the use of the model, roadway project managers can make informed decisions for roadway treatments based on energy consumption and GHG emission generation values. By incorporating the amount of energy that is consumed and GHG emissions generated into the decision making process of roadway infrastructure management, more sustainable infrastructure management can be achieved.
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Laboratory studies of biogeochemical processes in wetlands subject to simulated climate changeDowrick, David John January 1998 (has links)
No description available.
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