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Carbon Balance Implications of Forest Biomass Production PotentialPoudel, Bishnu Chandra January 2014 (has links)
Forests in boreal and temperate forest-ecosystems have importance for carbonbalance since they sequester large amount of atmospheric carbon by uptake ofcarbon-dioxide during photosynthesis, and transfer and store carbon in the forestecosystem. Forest material can be used for bio-fuel purposes and substitute fossilfuels, and supply wood products, which can replace carbon-and-energy-intensivematerials. Therefore it is vital to consider the role of forests regarding today´s aimto mitigate climate change. This thesis assess (i) how climate change affects futureforest carbon balance, (ii) the importance of different strategies for forestmanagement systems, and biomass production for the carbon balance, (iii) how theuse of forest production affect the total carbon balance in a lifecycle perspective,and (iv) how the Swedish carbon balance is affected from the standpoint of boththe actual use of forest raw material within Sweden and what Swedish forestryexports. The analysis was made mainly in a long-term perspective (60-300 years) toillustrate the importance of temporal and also the spatial perspective, as theanalysis includes stand level, landscape level, and national level. In this thesis, forestry was considered a system. All activities, from forestregeneration to end use of forest products, were entities of this system. In theevaluation, made from a systems perspective, we used life-cycle analysis toestimate carbon stock in different system flows. Different forest managementsystems and forest production were integrated in the analyses. Different forestmanagement scenarios were designed for the Swedish forest management incombination with the effect of future climate change; (i) intensive forest practiceaiming at increased growth, (ii) increased forest set-aside areas, changes in forestmanagement systems for biomass production, and (iii) how the use of forestproducts affect the total carbon balance (construction material, bioenergy and otherdomestic use). The results showed that future climate changes and intensive forest managementwith increased production could increase the biomass production and the potentialuse of forest raw material. This has a positive effect on carbon stock change in theforest biomass, litter production and below ground carbon stock and help reducingcarbon-dioxide emissions. Increased forest set-aside areas can increase the shorttermcarbon stock in forest ecosystems, but will reduce the total long-term carbonbalance. The net carbon balance for clear-cut forestry did not differ significantlyfrom continuous-cover forestry, but was rather a question of level of growth. Mostimportant, in the long term, was according to our analysis, how forest raw materialis used. Present Swedish forestry and use of forest raw material, both withinSweden and abroad, reduce carbon-dioxide emissions and mitigate climate change.The positive effect for the total carbon balance and climate benefit mostly takeplace abroad, due to the Swedish high level of export of wood products and thehigher substitution effects achieved outside Swedish borders. One strategy is toincrease production, harvest and use Swedish forest raw material to replace morecarbon intensive material, which can contribute to significant emission reduction.Carbon-dioxide mitigation, as a result of present Swedish forestry, was shown tobe almost of the same level as the total yearly emission of greenhouse gases. Thetotal carbon benefit would increase if the biomass production and felling increasedand if Swedish wood products replaced carbon intensive materials. This thesis shows also that, by changing forest management, increase thegrowth and the use of forest raw material and export of forest material we cancontribute to even larger climate benefits. In a long-term perspective, thesubstitution effects and replacement of carbon-and energy-intensive materials areof greater significance than carbon storage effects in forests. A more productionoriented forestry needs to make balances and increase the prerequisite forbiological diversity, improve recreation possibilities, and protect sensitive landareas and watersheds. Climate benefits, from Swedish forestry, are highly dependent on policydecision-making and how that can steer the direction for the Swedish forestry.
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Establishing a baseline diesel particulate matter (DPM) exposure profile for an underground mechanized platinum mine / Liebenberg, M.M.M.Liebenberg, Marlize Maria Magdalena January 2011 (has links)
Background: Workers are daily exposed to diesel exhaust (DE) and DPM due to the
continuous increase of diesel–powered vehicles in the underground mining environment. The
National Institute for Occupational Safety and Health (NIOSH) recommends that DE be
regarded as a “potential occupational carcinogen”. A great concern in the South African mining
industry is that there is currently no existing occupational exposure limits (OEL) for DPM.
Aim: To quantify the exposure of workers to DPM (that consists out of total carbon (TC): which
is a combination of elemental carbon (EC) and organic carbon (OC)) in the ambient air of
underground working environments. Also to compare different occupations exposure levels to
an international standard (the Mine Safety and Health Administration’s (MSHA) OEL for TC) as
South Africa has no proposed guideline or standard for occupational exposure to DPM and
finally to determine whether or not occupations working at mines with different mining methods
have different exposure levels to DPM.
Methodology: Workers personal exposure to DPM was monitored using the NIOSH 5040
method. A DPM sampler that consisted of a cyclone, a pre–packed SKC filter cassette (37 mm)
with impactor, tubing, label clips and a sampling pump was used. The flow rate was calibrated
at 2.0 litres per minute (L/min) for the sampling of sub–micrometer particles. The personal
sampler device was attached to the employee’s breathing zone for the duration of the work shift
(normal eight–hour time–weighted average (TWA) standard). A high risk group (workers
operating diesel–powered vehicles), a low risk group (workers working in the same mine,
sharing the same supplied air, but not operating these vehicles) and a control group (workers
working at a different mine with a different mining method) was monitored. The exposure levels
were evaluated and compared with the specific OEL mentioned previously.
Results: For the purpose of this study, TC exposure results were evaluated and not EC or OC.
All the occupations within their specific exposure group was exposed to TC. When the control
group’s exposures were compared with the high and low risk group exposures, a significant
difference was recorded (p–value = 0.0001). However when the high and low risk exposures
were compared with each other, no difference was recorded (p–value = 0.4405). When the
results of the various groups were compared with the MSHA OEL all the occupations from the
high and low risk group’s results were above the OEL, but only one occupation from the control
group exceeded the OEL.
Conclusion: It should be noted that all the occupations no matter the mining method / mine
was exposed to TC. The high and low risk exposure groups was however much higher than the
control group and a continues monitoring programme should be implemented for these
exposure groups. Their results exceeded the OEL, where the control group had much lower
exposure levels and only one occupation exceeded the OEL. Greater focus should be given to
the mechanized mining occupations since diesel–powered vehicles are used to perform their
core mining needs whereas at the conventional mine the use of these vehicles are limited.
Recommendation: Depending on the different occupations sampled various engineering
controls can be considered. Some include diesel oxidation catalysts (DOC), diesel particulate
filters (DPF) and diesel disposable exhaust filters (DEF) or also known as disposable diesel
exhaust filters (DDEF) which is very effective in removing DPM from the exhaust of dieselpowered
equipment. Education and training are also critical components to the success of a
diesel emission management programme and the last resort to be considered is the appropriate
personal protective equipment (PPE). South Africa should consider the implementation of
national standards in order to monitor the progress and success of the diesel emission
management programme implemented. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.
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Establishing a baseline diesel particulate matter (DPM) exposure profile for an underground mechanized platinum mine / Liebenberg, M.M.M.Liebenberg, Marlize Maria Magdalena January 2011 (has links)
Background: Workers are daily exposed to diesel exhaust (DE) and DPM due to the
continuous increase of diesel–powered vehicles in the underground mining environment. The
National Institute for Occupational Safety and Health (NIOSH) recommends that DE be
regarded as a “potential occupational carcinogen”. A great concern in the South African mining
industry is that there is currently no existing occupational exposure limits (OEL) for DPM.
Aim: To quantify the exposure of workers to DPM (that consists out of total carbon (TC): which
is a combination of elemental carbon (EC) and organic carbon (OC)) in the ambient air of
underground working environments. Also to compare different occupations exposure levels to
an international standard (the Mine Safety and Health Administration’s (MSHA) OEL for TC) as
South Africa has no proposed guideline or standard for occupational exposure to DPM and
finally to determine whether or not occupations working at mines with different mining methods
have different exposure levels to DPM.
Methodology: Workers personal exposure to DPM was monitored using the NIOSH 5040
method. A DPM sampler that consisted of a cyclone, a pre–packed SKC filter cassette (37 mm)
with impactor, tubing, label clips and a sampling pump was used. The flow rate was calibrated
at 2.0 litres per minute (L/min) for the sampling of sub–micrometer particles. The personal
sampler device was attached to the employee’s breathing zone for the duration of the work shift
(normal eight–hour time–weighted average (TWA) standard). A high risk group (workers
operating diesel–powered vehicles), a low risk group (workers working in the same mine,
sharing the same supplied air, but not operating these vehicles) and a control group (workers
working at a different mine with a different mining method) was monitored. The exposure levels
were evaluated and compared with the specific OEL mentioned previously.
Results: For the purpose of this study, TC exposure results were evaluated and not EC or OC.
All the occupations within their specific exposure group was exposed to TC. When the control
group’s exposures were compared with the high and low risk group exposures, a significant
difference was recorded (p–value = 0.0001). However when the high and low risk exposures
were compared with each other, no difference was recorded (p–value = 0.4405). When the
results of the various groups were compared with the MSHA OEL all the occupations from the
high and low risk group’s results were above the OEL, but only one occupation from the control
group exceeded the OEL.
Conclusion: It should be noted that all the occupations no matter the mining method / mine
was exposed to TC. The high and low risk exposure groups was however much higher than the
control group and a continues monitoring programme should be implemented for these
exposure groups. Their results exceeded the OEL, where the control group had much lower
exposure levels and only one occupation exceeded the OEL. Greater focus should be given to
the mechanized mining occupations since diesel–powered vehicles are used to perform their
core mining needs whereas at the conventional mine the use of these vehicles are limited.
Recommendation: Depending on the different occupations sampled various engineering
controls can be considered. Some include diesel oxidation catalysts (DOC), diesel particulate
filters (DPF) and diesel disposable exhaust filters (DEF) or also known as disposable diesel
exhaust filters (DDEF) which is very effective in removing DPM from the exhaust of dieselpowered
equipment. Education and training are also critical components to the success of a
diesel emission management programme and the last resort to be considered is the appropriate
personal protective equipment (PPE). South Africa should consider the implementation of
national standards in order to monitor the progress and success of the diesel emission
management programme implemented. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.
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A Study of Certain Organic Compounds of the Bottom Sediments of the Dundas Marsh, Hamilton, OntarioLarner, Elizabeth Anne 09 1900 (has links)
In the course of a little over a year, from January, 1950, to March, 1951, core samples of bottom sediments were collected at three different stations in the Dundas Marsh, Hamilton, Ontario. A number of the samples were analysed for total carbon content, bitumen, pectins, hemicelluloses, and cellulose and lignin content.
This study is part of a larger investigated by the Department of Zoology to ascertain the relationships between the biological productivity in lakes and the rate of mineralization of the organic detritus in lake bottom sediments. / Thesis / Master of Science (MSc)
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Auswirkungen verschiedener Bodennutzungssysteme auf ausgewählte physiko-chemische Bodeneigenschaften und pflanzenbauliche Parameter in Berlin-Dahlem und DedelowSümer, Mehmet Resat 19 February 2013 (has links)
Das Ziel dieser Arbeit war es, die Auswirkungen verschiedener Bodennutzungssysteme auf ausgewählte physiko-chemische Bodeneigenschaften und pflanzenbauliche Parameter auf sandigen Böden auf den Dauerfeldversuchsflächen in Berlin-Dahlem und Dedelow zu untersuchen. Ein erster Arbeitsschwerpunkt am Standort Berlin-Dahlem bestand darin, die Wirkungen verschiedener Bodenbearbeitungstiefen (17 cm und 28 cm) in Abhängigkeit der drei Faktorstufen - mit und ohne Kalkdüngung, mit und ohne Stallmistdüngung, flache und tiefe Bodenbearbeitung - zu ermitteln. Im zweiten Arbeitsschwerpunkt wurden in einer fünffeldrigen Fruchtfolge am Standort Dedelow Vergleiche verschiedener Verfahren der konventionellen und konservierenden Bodenbearbeitung und deren Effekte untersucht. Die Durchdringungswiderstandmessungen in Berlin-Dahlem zeigten nach langjähriger Bodenbearbeitung höhere Bodenfestigkeitswerte in der tieferen Bodenbearbeitungsvariante als in der flachen Variante. Die wasserstabilen Aggregate in Berlin-Dahlem wiesen in der flachen Bodenbearbeitung höhere Werte auf. Die ermittelten Wasserspeicherkurven in Berlin-Dahlem zeigten in der flachen Bodenbearbeitungsvariante für die ausgewählten Parzellen in 10-15 cm Bodentiefe im Vergleich zu der tieferen Variante tendenziell höhere nutzbare Feldkapazitätswerte. In Dedelow zeigten die Wasserretentionskurven unter verschiedenen Bodenbearbeitungsverfahren unregelmäßige Streuungen auf. Die höchsten Gesamtkohlenstoffgehaltswerte wurden in der flachen Bodenbearbeitung unter dem Prüfglied „mit Kalk- und mit Stallmist“ gedüngten Parzellen erzielt. In Dedelow zeigten die Gesamtkohlenstoffgehalte zwischen konservierender und konventioneller Bodenbearbeitung in 10-15 cm Bodentiefe kaum Unterschiede. Der Einfluss von Düngung und Bodenbearbeitungstiefen auf den Kornertrag bei Hafer war mit einem Ertrag von 29,2 dt ha-1 am stärksten am Standort Dedelow in der tiefen Bodenbearbeitung unter dem Prüfglied „mit Kalk- und ohne Stallmistdüngung“. / On the basis of various long-term field trials it was the goal to investigate the influence of different tillage systems on soil physical, soil chemical and crop parameters on sandy loamy locations in Berlin-Dahlem and Dedelow. The first focus of the work in Berlin-Dahlem was to investigate the effects between different tillage depths (17 cm and 28 cm) and the selected factors “with and without liming”, “with and without manure fertilization” and “shallow and deep tillage”. The second focus was on a five-field crop rotation site in Dedelow to compare different methods of conventional and conservation tillage and their effects. The penetration resistance values in Berlin-Dahlem showed after long-time tillage in the deep soil tillage system higher compactions compared to shallow tillage systems. The soil aggregate stability values in Berlin-Dahlem showed in the shallow tillage higher values. The obtained soil water retention curves in Berlin-Dahlem showed an increase of the available water capacity for the selected plots in the shallow soil tillage system compared to the deep tillage system in the 10 - 15 cm soil depth. The soil water retention curves showed irregular variations under the different tillage systems in Dedelow. The highest total carbon content were observed in the shallow tillage system in the "with lime and with farmyard manure" treatments. In general, however, the total carbon content predominate nearly the same amounts in 10 - 15 cm soil depth in both conservation and conventional tillage systems in Dedelow. The influence of fertilization and tillage depth on grain yield in oats showed the maximum value as 29,2 dt ha-1 in the deep tillage system in the "with lime and without farmyard manure" treatments.
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