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1
Pool, Christiaan Frederik. "The effect of modified fuel loads on fire behaviour in Pinus patula and Eucalyptus macarthurii stands in the Mpumalanga Highveld forestry region of South Africa." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1010958.
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The effectiveness of harvesting slash treatments are questionable when wild fires, fuelled by post harvesting slash, burn out of control. In order to quantify effectiveness of various slash treatments, fire behaviour in Pinus patula and Eucalyptus macarthurii compartments in the Highveld area (Piet Retief) of Mpumalanga, South Africa, were assessed after application of five different post-harvesting slash treatments. Treatments included mulching, chopper rolling, windrowing, removal of slash (inter-windrowing) and broadcasting. Independent fuel and environmental variables were measured prior and during application of fire to the study areas and effects on fire behaviour were compared afterwards. Dependant fire behaviour variables such as the rate of spread, fire temperature and flame height were measured in respective slash treatment plots and compared. Results of the study indicated that fire behaviour assessed in mulched areas in both the P. patula and E. macarthurii compartments were significantly less intense when compared to fire behaviour in chopper roll, broadcast and windrow treatments. Fire behaviour in mulched plots compared favourably with areas where harvesting slash was removed (inter-windrow treatment). Comparisons between fuel loads of different treatments also indicated accelerated mineralization of organic material in mulched areas. Mulching of harvesting slash seems to be an effective method to restrict fire behaviour in post-harvesting compartments and should be considered as part of a fire management strategy.
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Balfour, Victoria Nairn. "The effect of forest fires on runoff rates the role of duff removal and surface sealing by vegetative ash, western Montana /." Diss., [Missoula, Mont.] : The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-12202007-181528/.
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Roben, Charlotte. "Effect of cooling and non-uniform fires on structural behaviour." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/14292.
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Williams, Richard L. "Effects of a summer wildfire on populations of Rattus fuscipes and Antechinus stuartii in sclerophyll forest of south-eastern Australia." Thesis, The University of Sydney, 2007. https://hdl.handle.net/2123/28083.
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Wildfire has been important in shaping Australian ecosystems through its direct
and indirect effects on vegetation communities and faunal assemblages. Predictions that
wildfire incidence and intensity will increase with forecast changes in climate, make it
essential to understand wildfire impacts on native fauna and factors important for their
recovery. The intention of this thesis is to contribute to this knowledge base.
In December 2003 a high intensity Wildfire swept through large parts of
Booderee National Park in southeastern Australia. Using a replicated design I studied
the impacts of this fire on small mammal populations in open sclerophyll forest for 18
months after the fire. The small mammals present were Rattus fuscipes and Antechz'nus
stuartz'z'. Additionally, I experimentally investigated factors that may have limited small
mammals post-fire, specifically food and blood parasites. I monitored the response of R.
fuscipes and A. stuartii to a food supplementation experiment at both the population
level and at the scale of individual behaviour for one year.
Immediately following the wildfire, populations of both R. fuscz'pes and A.
stuartii declined to below 50% of populations unaffected by the fire. Rates of individual
survival were low during the fire and for the first 3 months after the fire, probably due
to high fire mortality, emigration and poor survival post-fire due to changes in resource
availability and predator impact with the depletion of vegetation in the fire. However,
within 18 months of the fire, populations of both species were present on all sites at
approximately 50% the size of those on unbumt sites; survival rates matched those on
unburnt sites and juveniles also were present in populations, indicating reproductive
recruitment. This rapid post-fire recovery was attributed to the seasonal timing and
patchiness of the wildfire, the presence of moist gullies in close proximity to study sites,
and seemingly low numbers of feral predators due to fox control.
The food supplementation experiment revealed that R. fuscipes was food limited
post—fire, with populations increasing 2-fold on burnt supplemented sites, probably due
largely to immigration and increased survival or residency of females. Behavioural
studies showed that the added food (rat breeder pellets) was generally used only as a
supplement because individuals did not aggregate around food stations or change their
patterns of habitat use. Instead they preferred the denser vegetation associated with
watercourses, which experienced rapid re—growth post-fire, just as did the individuals
that received no additional food. This preference for dense cover, despite the provision
of a constant and plentifiJl food source, suggests that predation risks are equally as
important as food for small mammals. A. stuartii showed no response to the food
supplementation despite accessing the food stations. This may be because the dried
pellets were not an appropriate food source for this insectivore. Prevalence of blood
parasite infection in R. fuscipes populations was not affected significantly by the
wildfire or food supplementation, suggesting that parasite infection did not contribute to
the variance in populations. However, any differences in host susceptibility between
populations was not measured.
The findings of this thesis have important implications for fire management in
Australian eucalypt forests, within the context of conserving populations of small
mammals and potentially other fauna. Future fire management regimes should aim to
achieve mosaic landscapes characterised by vegetation of varying seral stages. A regime
providing an intensity and frequency of burns that promotes plant diversity and
preferred habitat structure of mammals should be adopted. Moist habitats such as gullies,
swamps and rainforests should be protected from fire in any burning regime, or burnt
very infrequently and in small patches. Additionally, when planning fire regimes, the
breeding biology of fire-sensitive and threatened species should be considered, as
should additional management applications such as feral predator control and food
supplementation. The need for better planned and more comprehensive fire regimes will
become increasingly important in the future given the projections for increases in fire
severity and frequency with predicted changes in climate.
5
Odhiambo, Benedict Oithe. "The effect of fire damage on the growth and survival mechanisms of selected native and commercial trees in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96924.
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Thesis (PhD)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Surface fires are known to affect trees of different species differently, depending on the capacity of the bark to shield the cambium from heat. Tree bark characteristics differ among species and thus potentially influence the protective ability against cambium damage. The objectives of this study were to compare the protective role of bark against fire for selected indigenous and exotic species in the Western Cape, South Africa, and to investigate post-fire growth impacts following surface fire damage on Pinus radiata. In the first part of the study, trees were felled and billets of 25 cm height harvested from different heights along the trunk. Bark thickness, compass direction, stem diameter at breast height, bark moisture content and relative height of the sample in the stem were tested for their effect on heat insulation capacity of bark. Heating experiments were conducted at 400°C on the fresh billets with intact bark. Time to heat the cambium to lethal 60°C was determined. The second part of the study investigated the role of bark surface topology, bark density and bark chemical composition for its fire resistance. The same size billets were harvested from the lower trunk section of selected species. Surface topology was characterised by means of x-ray based computer tomography, density by moisture saturation method and bark chemical composition by thermo-gravimetrical analyses (TGA). The third part of the study investigated the impact of high intensity surface fires on growth of an 18 year old Pinus radiata plantation which was exposed to a ground fire 5 years prior to the analysis. Tree ring measurements were done on cores obtained by non-destructing coring method and various growth indices, based on yearly basal area increment (iBA) used to quantify growth response to the fire damage. Statistical analysis based on correlation, multi-model inference and multiple regression revealed no significant influence of compass direction and diameter at breast height. Heat resistance was mainly determined by bark thickness and to a lesser degree by moisture content. In several species relative height at the stem modulated the bark thickness effect. Higher up the stem bark of the same bark thickness offered less protection against heat. The results also suggest that in particular bark topology plays a role, while the correlations with bark density and chemical composition could not be secured statistically. A main finding was that fissures in the bark play a significant role. A regression model showed a significant influence of fissure width, fissure frequency and the minimum bark thickness to the cambium, which is a function of fissure depth. The results show that structural bark parameters are a necessary addition to explain heat resistance of bark. Statistical analysis employing one-way Anova and incorporating Tamhane’s T2 Post Hoc test revealed significant growth reductions following high intensity surface fire damage on Pinus radiata in the fire year with the impact being passed on to the following year. The recovery phase extended a two year period. During this time the trees showed increased diameter growth probably due to increased water availability.
AFRIKAANSE OPSOMMING: Dit is bekend dat oppervlakvure in bos-ekostelsels verskillende boomspesies verskillend affekteer, afhangende van die vermoë van bas om die kambium van hitte te beskerm. Baseienskappe verskil tussen spesies en het dus 'n potensiële invloed op die beskermende vermoë teen kambiumskade. Die doelwit van hierdie studie was om die beskermende rol van bas teen vuur te vergelyk tussen inheemse en uitheemse spesies in Wes-Kaapland, Suid Afrika asook om die na-vuur impak op groei te ondersoek met brandskade aan Pinus radiata. In die eerste deel van die studie is bome geoes en stompe van 25 cm lengte van verskillende hoogtes verwyder. Basdikte, kompasrigting, stompdiameter by borshoogte, basvoggehalte en die relatiewe hoogte van die stomp in die stam is getoets vir hul invloed op hitte-isolasiekapasiteit van bas. Verhittingseksperimente is gedoen teen 400 °C op die vars stompe wat steeds bas opgehad het. Die tyd om die bas tot by 'n skadelike 60 °C te verhit is bepaal. Die tweede deel van die studie het die rol van basoppervlaktopologie, basdigtheid, en die bas chemiese samestelling ondersoek in vuurweerstand. Dieselfde grootte stompe is geoes van die laer dele van die stam van uitgesoekte spesies. Oppervlaktopologie is bepaal deur middel van X-straal rekenaartomografie, digtheid deur die versadigingsvoggehaltemetode, en chemiese samestelling deur termo-gravimetriese analise (TGA). Die derde deel van die studie het die impak van hoë intensiteit oppervlakvure op groei van 18-jaar oue Pinus radiata ondersoek. Jaarringmetings is gedoen op inkrementboorsels wat nie-destruktief bekom is en verskeie groei-indekse, gebaseer op jaarlikse basale oppervlak aanwas, is gebruik om die groeireaksie op brandskade te kwantifiseer. Statistiese analise gebaseer op korrelasie, multi-model inferensie, en veelvuldige regressie het gewys dat kompasrigting en deursnee op borshoogte nie 'n beduidende invloed gehad het nie. Hitteweerstand was hoofsaaklik bepaal deur basdikte, en in 'n mindere mate basvoggehalte. By verskeie spesies het die relatiewe hoogte die basdikte-effek gemoduleer. Hoër in die stam het dieselfde dikte bas minder beskerming gebied as bas van laer in die stam. Die resultate impliseer dat basoppervlaktopologie ook 'n rol speel in hitteweerstand terwyl basdigtheid en chemiese samestelling nie 'n statisties beduidende rol gespeel het nie. 'n Belangrike bevinding was dat gleuwe of openinge in die bas 'n beduidende rol speel. 'n Regressiemodel wys dat 'n beduidende invloed deur gleufwydte, gleuffrekwensie en die minimum basdikte na die kambium. Die resultate wys dat strukturele basparameters 'n belangrike bykomende rol speel om hitteweerstand van bas te verduidelik. Die statistiese analise waar eenrigting ANOVA met Tamhane se T2 Post Hoc toets gebruik is toon dat ‘n beduidende groeivermindering teweeg gebring is in die Pinus radiata as gevolg van skade veroorsaak deur hoë intensiteit oppervlakvure waarvan die impak eers in die jaar na die vuur sigbaar was. Die herstelfase het oor twee jaar gestrek. Gedurende hierdie tyd het die bome 'n toename in deursneegroei getoon, waarskynklik as gevolg van verhoogde waterbeskikbaarheid.
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Mendenhall, Scout. "Effect of Deposition from Static Test Fires on Corn and Alfalfa." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1404.
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A greenhouse study was conducted to determine the effects of deposition from static rocket test fires on corn and alfalfa. Seeds were germinated in a wide concentration range of depositional material, called test fire soil (TFS). Additionally, the impact of chloride and aluminum, two major components of test fire soil, on germination was also evaluated. Furthermore, plants were grown in packed columns and exposed to test fire soil, either in the root zone or on foliage. Tissue was weighed and analyzed to compare biomass production and plant composition.
Corn and alfalfa exposed to test fire soil in the root zone produced less biomass than controls, but foliar treatment had no effect on biomass production. No kernels were produced by corn exposed to test fire soil in the root zone. Leaves of plants exposed to test fire soil in the root zone accumulated more metals and nutrients than controls, whereas plant tissue treated with test fire soil on the leaves contained only elevated levels of aluminum, although levels were still within reasonable concentrations for plants.
Germination of seeds was not affected below 1% test fire soil in soil; however higher concentrations of test fire soil decreased percent germination. Addition of chloride to soil also inhibits germination, but addition of aluminum has no effect on germination percentage. Corn germination was restored in test fire soil leached with 200 mm artificial rainwater.
The results of this research contribute information regarding the potential impact of test fire soil from static test fires on crop production. Test fire soil inhibits germination and growth if deposited in the root zone, and even foliar application alters tissue composition. However, plant composition is not altered significantly in terms of feed criteria, and germination can be restored by irrigating the TFS. The effects of test fire soil are attributed to high levels of chloride that induce salt stress. Crop damage may be avoided by conducting static test fires after crops are harvested or providing extra irrigation to soil impacted with the TFS.
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Kodandapani, Narendran. "Fire regimes and their ecological effects in seasonally dry tropical ecosystems in the Western Ghats, India." Diss., Connect to online resource - MSU authorized users, 2006.
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Myers, Alexandra. "A computational study of the effect of cross wind on the flow of fire fighting agent." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Jun%5FMyers.pdf.
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Ratsele, Clement Ratsele. "Long-term ecological effects of rangeland burning, grazing and browsing on vegetation and organic matter dynamics." Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1006844.
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To proffer a sustainable solution to ecological degradation in rangeland ecosystems as a consequence of fire, grazing and browsing, an understanding of rangeland ecological processes is vital. Due to the complexity of ecological processes and their interrelationships, it is usually difficult or expensive to directly measure status of ecological processes. Therefore, biological and physical characteristics are often used to indicate the functionality of ecological processes and site integrity. Long-term effects of fire, grazing and browsing on characteristics of the vegetation and organic matter and their subsequent effects on selected rangelands ecosystem ecological processes was conducted at Honeydale section of the University of Fort Hare farm in the Eastern Cape Province of South Africa and Matopos Research Station in Zimbabwe. In this study, attributes of biotic community integrity (species richness, composition and diversity), soil stability (basal cover, standing dead grass biomass, tuft to tuft distance, tufts diameter, canopy distance and stem to stem distance), productivity and plant vigour (grass yield, total canopy volume, plant height, canopy height, canopy diameter, main stem diameter, sprouts diameter and number of sprouts) and hydrologic function and nutrient cycling (grass litter biomass, soil organic carbon and microbial biomass carbon) were used to estimate long-term effects of burning, grazing and browsing by goats on the functionality of ecological processes in the rangeland ecosystem. Burning did not have differential effect on grass species richness (P>0.05), woody species diversity as well as compositional percentage for D.eriatha, C.plurinodis, S.fimbriatus, A.karro and E.rigida. Burning increased decreasers and increaser II species proportions and reduced (P ≤ 0.05) grass yield, total canopy volume, tree height, canopy height main stem diameter and sprouts diameter. Long-term burning, grazing, and goats browsing had differential effects on site stability. The effects on basal cover, tuft to tuft distance, tufts diameter, canopy distance and basal distance as a consequence of long-term burning, grazing, and goats browsing were not significantly different, whereas the effects on standing dead grass biomass as a result of long-term burning frequencies were significantly different. Long-term effects of burning followed by ten-year period of fire exclusion had significantly different effects on tuft-tuft distance but did not have statistically different effects on tufts diameter, canopy distance and basal distance. Long-term burning grazing and browsing had significantly different effects on attributes of hydrologic functions and nutrient cycling in the rangeland ecosystem (grass litter biomass, SOC and BMC). Long-term effects of burning followed by ten-year period of fire exclusion had significantly different effects on grass litter biomass, and SOC. Through their effect on vegetation and organic matter characteristics, burning, grazing and browsing could influence functionality of selected rangeland ecological processes such as biological community integrity, productivity and plant vigour, site stability, hydrologic function and nutrient cycling.
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Parsons, Russell Andrew. "Spatial variability in forest fuels simulation miodeling and effects on fire behavior /." CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05272008-141125/.
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Mansour, Khalid A. "Fires in large atmospheric storage tanks and their effect on adjacent tanks." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/12196.
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A suite of models were integrated to predict the potential of a large liquid hydrocarbon storage tank fire escalating and involving neighbouring tanks, as a result of thermal loading. A steady state pool fire radiant heat model was combined with a further model, in order to predict the distribution of thermal loading over the surface of an adjacent tank, and another model was incorporated to predict the thermal response of the contents of the adjacent tank. In order to predict if, or when, an adjacent tank will ignite, the radiant heat from the fire received by the adjacent tank must be quantified. There are a range of mathematical models available in the literature to calculate the radiant heat flux to a specified target and each of these models is based on assumptions about the fire. The performance of three of these models, which vary in complication, was analysed (the single point source model, the solid flame model and the fire dynamics simulator computational fluid dynamics model) and, in order to determine the performance of each model, the predictions made by each of the models were compared with actual experimental measurements of radiant heat flux. Experiments were undertaken involving different liquid fuels and under a range of weather conditions and, upon comparing the predictions of the models with the experimental measurements, the solid flame model was found to be the one most appropriate for safety assessment work. Thus, the solid flame model was incorporated into the thermal loading model, in order to predict the distribution of radiant heat flux falling onto an adjacent tank wall and roof. A model was developed to predict the thermal response of the contents of an adjacent tank, in order to predict variations in the liquid and vapour temperature, any increase in the vapour space pressure and the evolution of the vapours within the given time and the distribution of thermal loading over the surface of the tank as predicted by previous models; of particular importance was the identification of the possibility of forming a flammable vapour/air mixture outside the adjacent tank. To assess the performance of the response model, experiments were undertaken at both laboratory and field scale. The laboratory experiments were conducted in the Chemical Engineering Laboratory at Loughborough University and required the design and construction of an experimental facility representing a small-scale storage tank exposed to an adjacent fire. The field scale experiments were undertaken at Centro Jovellanos, Asturias, Spain. An experimental vessel was designed and fabricated specifically to conduct the laboratory tests and to measure the response of a tank containing hydrocarbon liquids to an external heat load. The vessel was instrumented with a network of thermocouples and pressure transmitter and gauge, in order to monitor the internal pressure and distribution in temperature throughout the liquid and its variation with time. The model predicting the thermal response of an adjacent tank was shown to produce predictions that correlated with the experimental results, particularly in terms of the vapour space pressure and liquid surface temperature. The vapour space pressure is important in predicting the time when the vacuum/pressure valve opens, while the liquid surface temperature is important as it governs the rate of evaporation. Combining the three models (the Pool Fire model, the Thermal Loading model and the Response model) forms the basis of the storage tanks spacing international codes and presents a number of innovative features, in terms of assessing the response to an adjacent tank fire: such features include predicting the distribution of thermal load on tanks adjacent to the tank on fire and thermal load on the ground. These models can predict the time required for the opening of the pressure vacuum relief valve on adjacent tanks and the release of the flammable vapour/air mixture into the atmosphere. A wide range of design and fire protection alternatives, such as the water cooling system and the minimum separation distance between storage tanks, can be assessed using these models. The subsequent results will help to identify any recommended improvements in the design of facilities and management systems (inspection and maintenance), in addition to the fire fighting response to such fires.
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Thomas, Paul B., University of Western Sydney, of Science Technology and Environment College, and School of Environment and Agriculture. "Effects of factors associated with the season of a fire on germination of species forming soil seedbanks in the fire-prone Hawkesbury sandstone region of Sydney, Australia." THESIS_CSTE_EAG_Thomas_P.xml, 2004. http://handle.uws.edu.au:8081/1959.7/697.
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Fire is a recurrent disturbance that removes above ground vegetation in many locations throughout the world, including the Sydney region. Many species in fire-prone locations, and most species in the Sydney region, form soil seedbanks and regenerate through post-fire germination. However, a germination response is determined by the fire regime acting as a selective pressure over a sufficient period of time, rather than a single fire. The components of the fire-regime are intensity, season, type and frequency. The natural fire regime is dominated by warm-season fire, but management burning is conducted in cooler seasons. Cool season burning produces lower levels of germination than warm season fires in a number of locations with Mediterranean-type climate, but the effects of cool season burning on species composition in the relatively aseasonal Sydney region is unknown. An experimental approach was adopted to address this lack of knowledge. Fire can be simulated using heat shock and smoke (fire cues), and the seasonal factors of temperature and water availability can be reproduced in the laboratory. I have investigated the effect of various combinations of heat shock and smoke, of various pre-and post-fire cue temperatures, of prefire cue hydration status, of various post-fire cue water availabilities, and of accelerated aging before application of fire cues on germination of a number of species forming soil seedbanks in the Sydney region. A degree of primary dormancy was overcome in most species by the combination of heat shock and smoke in the current investigation. Fire intensity is expected to influence germination, as germination of most species was increased by the combination of heat shock and smoke within a narrow heat shock range.The interaction between ambient temperature and the level of heat shock may affect germination. Soil water content, and thus seed moisture content at the time of a fire may interact with the level of heat shock to affect both germination and survival of a seed. The age of a seed may also affect its germination response to fire. The above factors are predicted to affect the germination of species differently, and thus season of fire is expected to alter species composition. Such predictions can be readily field-testedDoctor of Philosophy (PhD)
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Garrison, Trent. "The Environmental Effects of Coal Fires." UKnowledge, 2015. http://uknowledge.uky.edu/ees_etds/31.
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There are thousands of subterranean coal fires in the world that, because of incomplete combustion, emit a wide variety of volatile and semivolatile organic compounds to the atmosphere, water, and soil at concentrations that could pose health risks to humans and wildlife. The main goals of this study were to (1) review methods that are used to characterize physical and chemical characteristics of coal-fire sites, (2) determine relationships between gas emissions and physical and chemical characteristics of coal-fire sites, using a combination of regression and multivariate statistical methods, and (3) determine the concentrations of volatile and semivolatile organic compounds in water and soil at two coal-fire sites in eastern Kentucky. More specifically:
The objective of Chapter 1 was to review past works and list technologies used over time. Eight years of coal-fire collection technologies were reviewed. A variety of methods and technologies were identified. Qualitative and quantitative preferences were noted.
The objective of Chapter 2 was to identify and list uncontrolled coal-fire variables. These variables include complete/incomplete combustion; fire temperature and size; distance to fire; relative humidity and moisture in the system; geology, geochemistry, and age of coal; condition of the mine, sampling time of day; sampling equipment differences; and human error. A secondary objective of this chapter was to determine which coal-fire gases have strong relationships by using the principal component analysis (PCA) software JMP. The strongest relationship was between CO and H2S. Temperature and CH4 were also important. This indicates that incomplete combustion and polynuclear aromatic hydrocarbon (PAH) formation are likely occurring, setting the stage for Chapter 3.
The objective of Chapter 3 was to identify and define the extent of soil and water hydrocarbon contamination at the Truman Shepherd and Lotts Creek coal fires in eastern Kentucky. No groundwater contamination was detected at either location. Soil contamination was found at both, but was much higher at Lotts Creek, potentially because of sorption onto soil organic matter (which is reduced at Truman Shepherd by an excavation attempt) and other physicochemical mechanisms. Soil contamination was localized to relatively small areas around coal-fire vents.
Based on the results, future studies should consider: Attempting to duplicate these results in other geologic regions Quantifying greenhouse gas emissions from coal fires to consider their contribution to climate change. Coal-fired power plants are regulated, but coal fires, which produce many more harmful gases, are not Determining the feasibility of an oxygen-injection system to engender more complete combustion, therefore possibly reducing harmful gases Determining the feasibility of electricity production from coal fires Adopting a consistent federal coal-fire policy
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Campbell, Tessa Angela. "The effects of fire and harvesting on Restionaceae SPP. (Thamnochortus insignis and T. erectus) with different life histories : a matrix modelling approach." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2655.
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Thesis (MSc (Conservation Ecology and Entomology)--University of Stellenbosch, 2006.The Restionaceae is a dominant family in the Fynbos Biome, an area in which fire plays a role as an important disturbance, yet little is known about their population dynamics. Two species of the Restionaceae (Thamnochortus insignis and T. erectus) are economically important as thatching reed and differ in their life-histories. This study aims to determine the effects of variation in life history (sprouter vs. non-sprouter) on the population structure and dynamics of T. erectus (“wyfies riet”, sprouter) and T. insignis (“mannetjies riet”), a non-sprouting species. A matrix-modelling approach based on field data collected by Ball (1995) is used to determine population growth rates, stable stage distributions and stage sensitivity and elasticity for the two species with no disturbance present. The sprouter (T. erectus) shows a positive population growth rate (λ >1) and greater persistence within all stages. The non-sprouting species (T. insignis) shows a negative population growth rate (λ <1) between disturbances as well as greater seed production, germination and growth between stages. Based on the population dynamics of these two species, further research was done to understand the effect of disturbance (harvesting and fire) on these species. A matrix modelling approach was used to determine which disturbance frequency maximises population output and success. Harvesting as well as fire results in a decline in T. insignis populations. A five year frequency for harvesting results in the greatest output of adult plants with the lowest effect on the population, and a fire frequency of 50 to 65 years is recommended. Testing indicates that the model underestimates the number of adults in the population and thus the model is conservative. T. erectus populations grow despite fire or harvesting; thus any reasonable harvesting (3-5 year frequency) and fire (10+ years between fire) regime would ensure population persistence. As data were limited it was not possible to test the results although T. erectus appears resilient to disturbance and therefore a predetermined regime is not as important as in T. insignis. Recommendations to farmers are made based on these results.
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Villeneuve, Jasmin. "Influence des hautes températures sur la germination de graines de six espèces de conifères du Québec /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1991. http://theses.uqac.ca.
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Dowling, Patrick Kevin. "The Meteorological Effects of the Kuwait Oil Fires." W&M ScholarWorks, 1996. https://scholarworks.wm.edu/etd/1539626039.
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Murphy, Peter John. "Methods for evaluating the effects of forest fire management in Alberta." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25944.
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Programs for the prevention and control of forest fires have evolved in response to a need to protect lives and property in forested settings, and to protect the perceived values of the forest itself. However, costs of these fire management activities have always been a concern to those who provide the funds, and considerable effort has been directed towards attempts to determine optimal levels of management effort. The question of costs has become more acute in recent years as forest services have developed increasingly sophisticated yet expensive methods for controlling fires. Compounding the problem has been an increase in frequency of fires. Determination of appropriate levels of fire control has been hampered by a lack of knowledge about the relationship between expenditure on fire control activities and the resulting area burned and losses incurred, and by an inability to describe the effect on this relationship of variations in fire season severity.
This dissertation addresses these questions using the conditions in Alberta as a case study. Five hypotheses were tested and substantiated.
1. Descriptive historical accounts of fire policy and fire seasons can be verified by analysis of actual annual expenditures on fire. Annual reports were reviewed to describe the evolution of fire management policies.
2. There has been a decrease in area burned which is related to increased fire management effort. Analyses of age-class distribution obtained from the provincial forest inventory were used as a basis for reconstructing an estimate of historical rates of burn for the past 80 years. Cost data were obtained to try to quantify the relationship between level of expenditure and rate of burn.
3. Variations in fire season severity can be described better than by existing methods by considering both the potential for fire spread and the actual number of fires. A new index of fire load which combined fire rate of spread with number of fires was developed which achieved this result.
4. Potential area burned in the absence of fire control may be estimated by means of a fire growth model. A fire growth model was developed to provide a mathematical basis on which to estimate area burned in the absence of any fire management activity.
5. There is a relationship among fire season severity, fire management effort, and area saved from burning. The combined relationships among fire season severity, fire management effort, and area burned or value were applied to illustrate some of the analyses which may be conducted with these data through evaluation of the Alberta situation.Forestry, Faculty of
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Lata, Mary Elizabeth. "Variables affecting first order fire effects, characteristics, and behavior in experimental and prescribed fires in mixed and tallgrass prairie." Diss., University of Iowa, 2006. http://ir.uiowa.edu/etd/72.
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White, Katrina Marie, and University of Lethbridge Faculty of Arts and Science. "Effects of fire on a prairie arthropod community." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2000, 2000. http://hdl.handle.net/10133/125.
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In this study, I addressed how a large-scale wildfire affected a prairie arthropod community in southern Alberta, Canada. First, I looked at the general effects of disturbance on the arthropod community. Second, I addressed how processes such as competition and secondary succession may have affected diversity in this arthropod community. Third, I determined how the arthropod community trophic structure was regulated.
Results showed that the effect of disturbance on arthropods varies greatly by taxa. Factors, such as site, year, distance from disturbance edge, as well as the disturbance itself, were important in determing the abudance, biomass, richness, and diversity of the arthropod community. There were strong year-to-year differences hat exceeded the disturbance effects. Results showed that the processess behind the intermediate
disturbance hypothesis, succession and competition are not detectable in this arthropod community. This arthropod community was likely regulated in a bottom-up manner, in which herbivores ultimately control the abundance of predators and parasitoids.x, 97 leaves : ill. ; 28 cm.
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Bakar, M. Z. Abu. "A study of the effect of tunnel aspect ratio on control of smoke flow in tunnel fires." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312744.
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Lombard, Pieter Jacobus Lategan. "The long term effects of fire frequency and season on the colophospermum mopane shrubveld of the Kruger National Park." Thesis, Port Elizabeth Technikon, 2003. http://hdl.handle.net/10948/257.
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Background : The recorded history of veld burning in the Kruger National Park (KNP) started with the appointment of Colonel James Stevenson-Hamilton as warden of the Park (then the Sabie Game Reserve) in July 1912 and can be divided into five periods: From 1912 to 1926, a haphazard, and indecisive burning policy was practiced, mainly due to the perception that fire was unfavourable for the environment and because the means to combat veld fires were very meagre. From 1926 to 1948, in which period it was realized that fire was not only unavoidable over a large area such as the KNP, but also actually desirable, necessary and beneficial when applied with circumspection. During this period the capability to successfully introduce and apply a definite fire policy did not exist. From 1948 to 1956, prescribed burning was not practiced, but a network of graded firebreaks was being established (to create burning blocks), and wild fires were actively combated. From 1957 to 1993, during which period a definite prescribed burning policy was practiced, amended several times, but basically consisting of a triennial rotational system where blocks were burned by management. All fires of non-management ignition sources were combated. From 1993 to the present, when a policy of allowing lightning-ignited fires to burn freely was introduced, and fires of human origin were suppressed. The shift away from a rigid prescribed burning programme was because of the concern that the dominance of grass species characteristic of over utilised veld was a result of too frequent burning (Potgieter, 2001). Lightning fires probably played just as an important role in shaping African savanna in pre-industrial times as anthropogenic fires caused by preindustrial man. The role of post-industrial man as far as its influence on the creation of savanna is concerned is probably negligible, but significantly important in the role of maintaining savanna, although probably not more so than that of lighting fires. Fires caused by postindustrial man becomes suspect as far as the creation of savanna is concerned, because instead of the mere burning of the veld for the pure reasons of survival as practiced by pre-industrial man, a measure of commercialism crept in (Potgieter, 2001). Fire management of the KNP in pre-industrial times can be regarded in the same light as that of post-industrial times. Although the motive for burning the veld in the KNP was beyond reproach, the underlying reasoning was not. Managers’ thinking was geared towards preventing so called “devastating fires”, laying to waste large areas of the Park, not realising that this was in actual fact nature going about its business in this ecosystem. They therefore devised a system of firebreak roads, which was gradually extended to the extent that we now have more than 4000 km roads that must be maintained. This was all in the cause of preventing or managing lightning and arson fires. Given the above, a revision of the veld fire policy was extremely necessary. The mission statement hammered out during the revising process in 1993 underscored and supported the proposal put forward in 1992, that lightning fires should be recognised as a legitimate and completely natural phenomenon in the Lowveld ecosystem. This had to be weighed against the prevailing practice of combating all fires caused by lightning and non-management anthropogenic sources of fire. The essence of this policy would therefore be to allow lightning-fires to burn to their full extent i.e. if vegetation conditions (available biomass) are such that large areas will burn, then such burns will be permitted to proceed to their full extent with the provision that no more than 50% of the management unit will be allowed to burn out (no matter what the ignition source) in a specific fire season (Potgieter, 2001).
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Radford, M. W. "An Investigation of the Effects of Sprinklers on Compartment Fires." University of Canterbury. Civil Engineering, 1996. http://hdl.handle.net/10092/8289.
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The effects of automatic sprinklers on compartment fires has been investigated in this report. The interaction of a sprinkler spray with a buoyant hot upper layer has also been examined.
A model was developed to predict the rate of smoke production and hence the depth of a smoke layer that may be produced, for an uncontrolled growing fire. Flow out of vents was included in this model. The model compared well to the predictions of 'Firecalc'.
An method for the prediction of detector actuation has been used that is valid for growing fires, avoiding the quasi-steady assumption used in 'Firecalc' and 'FPEtool'. This method also includes the transport lag time of the fire signature from the source to the detector.
The interaction of a sprinkler spray with a fire induced hot upper layer is a very complex problem. The combining effects of drag induced on the upper layer and evaporative cooling by the sprinkler spray may cause the layer to fall to a lower level.
The model developed to predict the rate of smoke production, hence smoke layer depth, is only valid for uncontrolled fires. Time constraints prevented the effects of sprinklers on compartment fires to be incorporated into this model, although the theory of the effects is included with this report.
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Eldiabani, Gibrel S. "Forest fires and their effect on chemical and physical properties of soils in North-eastern-Libya. Assessment of the changes in soil chemical and physical properties of soils in North-eastern-Libya." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5402.
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Forest areas are particularly susceptible to fires, which are often manmade. Too-frequent fires are likely to adversely affect the soil properties as well as vegetation composition, and possibly lead to soil erosion and desertification. One of the most fire affected forest regions in the world is the Mediterranean. Libya, in the Mediterranean region, has soils that are considered to be arid except in a small area called Aljabal Alakhdar (Green mountain), which is the geographic area covered by this study. It is the wettest part of Libya, and has an extensive forest and many agricultural crops. Like other forests in the Mediterranean it has suffered extreme degradation. This is mainly due to people removing fire wood, or sometimes converting forested areas to agricultural use, as well as fires which may alter several soil chemical and physical properties. The purpose of this research was to evaluate the effects of fires on the physical and chemical properties of soil of Aljabal Alakhdar forest in the north-east of Libya. The physical and chemical properties of soil following fire in two geographic areas have been determined, with those subjected to the fire compared to those in adjacent unburned areas in one coastal and one mountain site. Physical properties studied were: soil particle size, soil water content, soil porosity and soil particle density; and chemical properties studied were: soil electrical conductivity (EC), soil pH, soluble and exchangeable Na, K, Ca and Mg, cation exchange capacity (CEC), soluble Cl, CO3 and HCO3, SO4, organic matter, total N and total P. For the first time in Libyan soils, the effect of burning on the magnetic susceptibility properties of soils was also tested. The results showed that except for the soil water content and magnetic susceptibility, fire has not had a clear effect on the soils¿ physical properties, while there has been a strong impact of fire on most of the studied chemical properties. These results have been used to create an index of burning for such soils in each of the geographic areas, as a step towards creating a model which will enable a subset of soil parameters to be used to estimate how recently a site was burned, as well as defining fire severity at a site.Libyan Government
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Nacewicz, Rebecca Marie. "Investigation of fire impact on structural steel through case studies." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-050406-105306/.
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St, Onge Peter Douglas. "The effect of clearcut logging and forest fires on hypolimnetic oxygen depletion rates in remote Canadian Shield lakes /." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33032.
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Thirty-eight oligotrophic lakes located around the Reservoir Gouin in central Quebec (48°N, 75°W) were sampled over three years to test the hypothesis that forest clearcutting and fires should be reflected in both higher nutrient export rates and ultimately in greater areal hypolimnetic oxygen deficit rates (AHOD). Significant differences in estimated total phosphorus export rates across treatments were found. However, no effect of clearcutting or forest fire on hypolimnetic oxygen consumption rates could be demonstrated as the result of a much greater and confounding variation in the effect of lake morphometry and the absence of information on the role of catchment-derived organic matter on the AHOD. Consequently, only lake morphometry (hypolimnetic volume to hypolimnetic surface area ratio) served as a predictor of the AHOD. Covariation of mean hypolimnetic water temperature with morphometric variables underlines the influence of lake morphometry on heat dynamics and hypolimnetic respiration rates in these lakes.This research made considerable use of specialized data manipulation techniques involving a relational database management system, owing to the size of the dataset used (114 lake-years of data). The specific approach used in this thesis is presented in an appendix.
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Salvo, Aires Felipe. "Effects of woody weeds on fuels and fire behaviour in Eastern Australian forests and woodlands." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/12839.
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Fire is a common feature in most ecosystems in Australia. Much of the native flora is well adapted to occasional fire and recovers over time in a variety of ways. Invasive species or ‘weeds’ are also a common feature in most Australian ecosystems, particularly in forests and woodlands close to urban settlements. Many invasive species have the potential to recover or recolonise more rapidly following disturbance than native species and may change the fuel load and structure of invaded areas. Invasive species can alter the fuel load and structure providing the fine fuel necessary for initiation and propagation of fire. Woody weeds can also provide elevated biomass to sustain fire and ‘ladder fuels’ allowing fire to reach the canopy. When both of these elements are considered there is the likelihood of alteration of fire behaviour in weed-infested areas of forests and woodlands. The research described in this thesis aims to investigate the effect of invasive species on fire in woodlands of eastern Australia. The fuel load, fuel structure and flammability of pristine (non-invaded) Cumberland Plain Woodland (Australian Botanical Garden, Mount Annan, New South Wales, Australia) and adjacent areas invaded with the woody weed, African Olive (Olea europaea subsp. cuspidata), was assessed and compared. Heavily-invaded areas are comprised of mature trees of African Olive present for more than 15 years, with a continuous canopy and a limited number of species in the understorey were contrasted with areas of ‘intermediate’ invasion, where immature trees of African Olive were interspersed among a grassy/shrubby matrix, and areas of pristine woodland.
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Landmann, Tobias. "A case study for Skukuza : estimating biophysical poperties of fires using EOS-MODIS satellite data ; a field and remote sensing study to quantify burnt area and fire effects in South African semi-arid savannas /." Aachen : Shaker-Verl, 2004. http://www.loc.gov/catdir/toc/fy0708/2006485603.html.
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Eldiabani, Gibrel Salah. "Forest fires and their effect on chemical and physical properties of soils in North-eastern-Libya : assessment of the changes in soil chemical and physical properties of soils in North-eastern-Libya." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5402.
Full textAbstract:
Forest areas are particularly susceptible to fires, which are often manmade. Too-frequent fires are likely to adversely affect the soil properties as well as vegetation composition, and possibly lead to soil erosion and desertification. One of the most fire affected forest regions in the world is the Mediterranean. Libya, in the Mediterranean region, has soils that are considered to be arid except in a small area called Aljabal Alakhdar (Green mountain), which is the geographic area covered by this study. It is the wettest part of Libya, and has an extensive forest and many agricultural crops. Like other forests in the Mediterranean it has suffered extreme degradation. This is mainly due to people removing fire wood, or sometimes converting forested areas to agricultural use, as well as fires which may alter several soil chemical and physical properties. The purpose of this research was to evaluate the effects of fires on the physical and chemical properties of soil of Aljabal Alakhdar forest in the north-east of Libya. The physical and chemical properties of soil following fire in two geographic areas have been determined, with those subjected to the fire compared to those in adjacent unburned areas in one coastal and one mountain site. Physical properties studied were: soil particle size, soil water content, soil porosity and soil particle density; and chemical properties studied were: soil electrical conductivity (EC), soil pH, soluble and exchangeable Na, K, Ca and Mg, cation exchange capacity (CEC), soluble Cl, CO3 and HCO3, SO4, organic matter, total N and total P. For the first time in Libyan soils, the effect of burning on the magnetic susceptibility properties of soils was also tested. The results showed that except for the soil water content and magnetic susceptibility, fire has not had a clear effect on the soils' physical properties, while there has been a strong impact of fire on most of the studied chemical properties. These results have been used to create an index of burning for such soils in each of the geographic areas, as a step towards creating a model which will enable a subset of soil parameters to be used to estimate how recently a site was burned, as well as defining fire severity at a site.
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Rust, Stephanus Marthinus. "Classification of timber from Pinus radiata trees exposed to forest fires." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/98097.
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Thesis (MSc)--Stellenbosch University, 2015.ENGLISH ABSTRACT: This study aimed to classify wood from trees that were exposed to forest fires with regards to their end use. Exposure to high temperatures over time is known to degrade wood in various ways. This degradation could limit the end use by altering mechanical, chemical and physical properties, leading to difficulty in processing or failing to meet required specifications for various grades. In this study wood from Pinus radiata trees that were exposed to forest fires of different levels of heat intensity was analysed with regards to its anatomical and physical changes. Trees were visually classified into three classes of burn severity. Moisture content measurements were taken from 135 standing trees, divided among the three classes. 30 trees, 10 from each of the three classes, were sampled and used for CT analysis. Samples were taken to include growth from before and after the fire. Two samples were taken from each tree, one from the charred and one from the uncharred side. The CT data was analysed and used to measure properties like growth ring width, cell wall thickness, lumen diameter and cell wall density. The data was used to compare properties from the charred and uncharred sides within a given year, as well as compare properties between years. The study showed that there were significant differences in the MC between the burnt and unburnt sides of trees from classes 2 and 3. The difference between the MC measurements on the burnt sides of three classes differed significantly from each other. Lightness measurements were taken on samples from classes 2 and 3. These samples showed no significant difference between the burnt and unburnt sides for either of the two classes. The samples from the less exposed class were lighter, but not significantly so. The macroscopic wood density was determined using core samples. A decrease in wood density was observed with an increase in fire exposure. The mean densities for all three classes however still fulfilled the requirements for structural timber set by the SABS. Growth ring width, cell wall thickness and lumen diameter analysis gave varied results, with some cases showing a decline in properties while others were seemingly unaffected. For many of the outcomes of this study, results found by previous studies could not be reproduced.
AFRIKAANSE OPSOMMING: Hierdie studie het gepoog om bome wat aan plantasiebrande blootgestel is volgens hul eindgebruik te klassifiseer. Dit is bekend dat blootstelling aan hoë tempreature hout in vele maniere afbreuk. Hierdie afbreuking kan die eindgebruik van die hout beperk deur die meganiese, fisiese en chemiese eienskappe sodanig te verander dat dit kan lei tot probleme met verwerking of ongeskiktheid vir sterktegrade. In hierdie studie is Pinus radiata bome wat aan plantasiebrande van verskillende grade blootgestel is ondersoek in terme van hul fisiese en anatomiese veranderinge. Bome is visueel in drie klasse van verskillende brandskade gegroepeer. Voglesings is op 135 staande bome, verdeel tussen die drie klasse, geneem. Monsters is van 30 bome, 10 uit elke klas, geneem vir CT analiese. Monsters is so geneem dat dit groei van voor en na die brand ingesluit het. Daar is twee monsters van elke boom geneem, een van die gebrande en een van die ongebrande kant. Die CT data is geanalieseer en gebruik om eienskappe soos jaarringwydte, selwanddikte, lumendiameter en selwand digtheid te meet. Die data is gebruik om eienskappe tussen die gebrande en ongebrande kante, sowel as tussen jare te vergelyk. Die studie het gewys dat daar noemenswaardige verskille is tussen die voginhoud van die gebrande en ongebrande kante van bome uit klasse 2 en 3. Die voginhoud van die gebrande kante van al drie klasse verkil ook noemenswaardig van mekaar. Ligtheidmetings is gedoen op monsters van klasse 2 en 3. Die monsters het nie ‘n noemenswaardige verskil tussen die gebrande en ongebrande kante getoon nie. Alhoewel die klas 2 monsters ligter vertoon het as die klas 3 monsters, was die verskil nie betekenisvol nie. Houtdigtheid is bepaal deur fisiese metings op die monsters wat vir die CT skandering gebruik is te doen. ‘n Daling in digtheid met ‘n toename in blootstelling aan die brand het duidelik na vore gekom. Die digtheid is egter nog hoog genoeg om aan die vereistes vir strukturele hout te voldoen, soos die die SABS bepaal. Jaarringwydte, selwanddikte en lumen diameter het wisselende resultate opgelewer, met sommige gevalle wat ‘n afname in eienskappe wys en ander wat ooglopend onveranderd was. Vir vele van hierdie uitkoms kon die resultate van vorige studies nie bevestig word nie.
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Parkinson, David L. "Performance based design of structural steel for fire conditions." Link to electronic thesis, 2002. http://www.wpi.edu/Pubs/ETD/Available/etd-0821102-115014.
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Mounaud, Laurent Georges. "A Parametric Study of the Effect of Fire Source Elevation in a Compartment." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/30916.
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The objective of the present study was to acquire a better understanding of parameters controlling the species generation and transport from compartment fires. The experiments were performed in a half-scale ISO 9705 compartment and a 6.1 m long hallway connected in a head-on configuration. The buoyancy driven propane fire was provided by a burner and a continuous gaseous fuel supply system. All the measurements were obtained during the steady state of the fire. The ventilation conditions were fixed and three different fire source elevations were studied for heat release rates ranging from 20 kW to 150kW.
The species yields were obtained from performing detailed mapping measurements at the compartment and hallway exit planes. The measurements included local specie mole fractions of oxygen, carbon dioxide, carbon monoxide and unburned hydrocarbons. The local temperature and the local pressure (for local gas velocity calculations) were also measured. In addition, visual observations of the flow dynamic were performed through a window and the vents to give useful insights and lead to a better understanding of the combustion process.
The data obtained from the species generation study was analyzed using previously developed methods. The method based on equivalence ratio was presented and determined inappropriate for the present study where the global equivalence ratio was not equal to the plume equivalence ratio due to the complexity of the fire dynamic taking place. The method consisting of correlating the species yields based on the combustion within the compartment as a function of a non dimensional heat release rate allowed qualitative conclusions to be made. The non-dimensional heat release rate was based on the fuel load and the geometric parameters of the compartment. This methodology revealed similarities in the species production between the three fire source elevations investigated. A correlation of the data was obtained based on experimental data.
The transport of species to remote locations was studied for the three fire source elevations and fixed ventilation conditions. Species mole fractions and yields were obtained at the compartment exit plane (compartment/hallway interface) and at the hallway exit plane. The results were compared for various heat release rates and showed differences for some scenarios attributed to mixing along the hallway and oxidation reactions outside the compartment.Master of Science
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Spriggs, Amy. "Dowsing fynbos fires with sea water. An investigation into the effects of utilising sea water dropped by helicopter to extinguish fires in Cape Mountain fynbos." Thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/26391.
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Stanton, Rebekah L. "Fire and Rodent Consumer Effects on Plant Community Assembly and Invasion in North American Deserts." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/9172.
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This dissertation explores the differential effects of fires and rodent communities on native and invasive desert plant communities. Chapter one examines the impacts of fire and repeat fires on fuel loads in two different Utah desert sites, one in the cool Great Basin Desert and one in the hyper-arid Mojave Desert, over the course of four years. We found that both desert sites responded with varying intensities to a single burn, but the effects of a reburn were not as pronounced. We also found that our Great Basin Desert site had a stronger response to fire than our Mojave Desert site, producing a higher plant fuel loads that could potentially exacerbate the changing fire regimes. These data can be used to help map the effects that climate change may have on fuel loads and the fire potential of these deserts. Chapter two uses a full factorial experimental design to compare the effects of rodent herbivory and fire on native versus invasive seedlings at our Mojave Desert field site. We found that rodent herbivory has a more negative impact on the survival of native seedlings than invasive seedlings. This could be because the invasives are grasses that tend to tolerate herbivory better than the native shrubs and forbs. Chapter three again uses a full factorial experimental design to assess the impacts of rodents and fire on the fate of native and invasive seeds at our field site in the Mojave Desert. We found that rodents removed seeds, and they did show preferences for some species of seed over others, but these preferences were not different between native and invasive seeds or seed mass. We propose that the preferences may be influenced by other seed traits such as water content, handling time or physical and chemical defenses. As with the seedlings in chapter two, fire did not have any impact on rodent seed preferences. These data highlight the importance of considering rodent effects on seeds used in restoration effects following wildfires.
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Kirchner, Brianna N. Wilkins Kenneth T. "Indirect effects of fire on the small mammal community of a tallgrass blackland prairie remnant in Texas." Waco, Tex. : Baylor University, 2009. http://hdl.handle.net/2104/5304.
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Johnson, Kenneth B. "Fire and its Effects on Mercury and Methylmercury Dynamics for Two Watersheds in Acadia National Park, Maine." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/JohnsonKB2002.pdf.
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Tolsma, Arn Douwe. "The Effects of fire and grazing on the energy reserves of resprouting plants in Victoria's alpine grasslands /." Connect to thesis, 2002. http://eprints.unimelb.edu.au/archive/00000331.
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Pinheiro, Fabiola M. R. "Effects of forest fires and clear-cutting on mercury loading to boreal lakes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0034/MQ64431.pdf.
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Hu, Zhixin. "Flame extinction and air vitiation effects in FDS In poorly ventilated compartment fires." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/3001.
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Thesis (M.S.) -- University of Maryland, College Park, 2005.Thesis research directed by: Dept. of Fire Protection Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Landmann, Tobias. "A case study for Skukuza : estimating biophysical properties of fires using EOS-MODIS satellite data : a field and remote sensing study to quantify burnt area and fire effects in South African semi-arid savannas /." Aachen : Shaker, 2004. http://www.loc.gov/catdir/toc/fy0708/2006485603.html.
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Bois, Claudette Hélène. "The effect of timber harvest and wildfire on soil physical and nutritional dynamics in two boreal forest ecosite types in eastern Manitoba /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80229.
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Forest ecosystems undergo both natural and human induced disturbances. Depending on disturbance type, soil physical and chemical parameters show different response patterns during the recovery phase. An added level of complication is the ecological site types occurring throughout a forested area. The identification of indicators of soil fertility and the successful emulation of a natural disturbance regime were the scope of this research.The research presented herein took place in the Manitoba Model Forest (MBMF), located in eastern Manitoba, where the natural disturbance regime is wildfire. Timber harvest strategies used in the area are designed to emulate a wildfire (5% retention of standing timber and extensive slash inputs) and clearcut harvesting. The objective of this study was to document changes in forest floor and soil properties prior to and following harvesting, and to compare these properties to those found in a small wildfire that burned in the MBMF in late summer 1998, which serves as a benchmark to the harvest. In the two study areas, both thin mineral soil (5--20 cm) and moderately deep mineral soil (20--100 cm) ecosite types were monitored at four dates over a two year period for soil physical and nutritional response patterns.
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Maghran, Lauren A. "Recovery and Changes in Plant Communities from Two Large Fires in the Santa Catalina Mountains, Arizona, USA." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/337365.
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In mountains throughout western North America, large, mixed-severity fires produce a mosaic of low and high tree mortality. Following wildfire, plant communities may recover to their pre-fire state, or may remain altered in composition and structure. In this study I quantified the extent to which fire severity influenced post-fire vegetation composition and structure in comparison to pre-fire states in the Santa Catalina Mountains, Arizona, USA. I used a stratified random design that sampled plots across ecological units and fire severity classes. Tree diameter at breast height (DBH), shrub cover, and seedling and sapling density was recorded by species in five plant communities: oak/pinyon/juniper woodland on hills landscapes of mixed lithology; Madrean pine-oak forest/woodland on granite, gneiss, or metasedimentary rock; Madrean oak/conifer/manzanita on rock outcrops; ponderosa pine forest on granite, gneiss, and similar rocks; and mixed conifer forest on metasedimentary landscapes. Subsets of these data were then used to reconstruct overstory vegetation present when the Bullock (2002) and Aspen (2003) fires occurred. Data from a 1984 pre-fire study was used to substantiate the overstory reconstruction and to determine shrub understory components. I tested the hypothesis that tree mortality was a determinant of post-fire shrub cover, and calculated post-fire importance values (IVs) of tree and shrub components. Ordination and non-metric multidimensional scaling (NMS) of IVs confirmed that overstory reconstruction aligned with 1984 field surveys. Tree mortality was a predictor of post-fire shrub cover, but only with certain species in specific ecological units. Ordinations indicated that tree composition in post-fire plots has diverged from that in pre-fire plots in all but the oak/ pinyon/juniper community. Ordination of shrub components indicated novel configurations of post-fire communities, including association of pre-fire mixed conifer elements with oak woodland elements. The intermixing of tree species in mid- and higher-elevation communities with those historically confined to lower elevation community types suggests that recent fires has disrupted vegetation inertia and initiated novel ecological change. The re-structuring observed within these community types are in agreement with projections that disturbance and climate change will interact to facilitate the spread of lower elevation species to higher elevation zones. Fire x climate interactions may therefore trigger long-lasting changes to ecosystem structure in ways not predicted by models of fire-effects or climate-effects occurring in isolation from each other.
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Hellberg, Erik. "Historical variability of deciduous trees and deciduous forests in northern Sweden : effects of forest fires, land-use and climate /." Umeå : Dept. of Forest Vegetation Ecology, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/s308.pdf.
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Yii, Ee Hieng. "Modelling the effects of fuel types and ventilation openings on post-flashover compartment fires." Thesis, University of Canterbury. Civil Engineering, 2002. http://hdl.handle.net/10092/7728.
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This thesis describes the details used to model a post-flashover fire compartment as a well-stirred reactor. In particular, it examines the two foremost important variables that dictate post-flashover fire behaviour inside the fire compartment. These two variables are: (1) the mass flow rate of air into the compartment via the vent opening and (2) the fuel mass loss rate inside the compartment.
The vent flow analysis shows that the orifice analogy typically used to describe compartment vent flow is restricted to small wall opening applications. For large wall openings, such as a window occupying one whole wall, the flow rate is dictated by the plume entrainment with a flow rate -60% of the flow rate estimated from the orifice theory.
A series of fire experiments using a reduced-scale compartment were conducted to study the vent flow behaviour in a compartment with a horizontal roof opening and a vertical wall opening. Based on the analytical and experimental studies, it is shown that in the case where the roof vent opening is not excessively large and a wall opening having a small downstand, the neutral-plane exists below the soffit of the wall opening giving outflow and inflow through the wall opening and outflow through the roof opening. In such a case, the flows through these openings can be adequately described using an extended form of the vent flow formulation that includes the roof vent opening. The area of the roof vent and the depth of the downstand between the ceiling and the soffit of the wall opening are found to be significant in determining the extra air inflow induced due to the existence of the roof vent opening.
The cellulosic and pool fuels each have different burning behaviour inside a compartment. However, compartment fire temperatures and fuel mass loss rates, from both fuel types, are strongly dependent on the available fuel surface area to ventilation opening ratio and the fuel surface to enclosure area ratio. In the case of thermoplastic pool fires, the ratio between the heat of combustion of air for the fuel and the heat of gasification of the fuel is also found to be influential on the resulting fires.
A post-flashover fire computer program, CFIRE, has been developed that incorporates these findings. The simulation studies performed using the CFIRE computer program show that the fire time-temperature histories of wood fires are highly dependent on the remaining fuel surface area over time. In the case of thin wood, a shorter and hotter fire is expected as it has greater surface area than thick wood, even with the same fuel load. The study also shows that for small ventilation opening, a pool fire inside a fire compartment is less severe than a wood fire because the thermoplastic fuel is easily vaporised under the radiation feedback from the hot surrounding environment and discharged outside the compartment. In the case of large openings, pool fires are more likely to produce a hotter fire in the compartment than wood fires because wood fuel would not have sufficient fuel surface area to achieve ventilation controlled burning.
By comparing these simulated fires with the Eurocode parametric fires, the Eurocode parametric fires do not provide realistic decay rate. With the modified parametric fires, these fires are conservative as they provide envelopes for the simulated fire curves. However, these parametric fires do not clearly describe the fire behaviour of realistic furnishing inside the fire compartment.
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Chatenet, Sarah. "An instrumented controlled-atmosphere cone calorimeter to characterize electrical cable behavior in depleted fires." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R047.
Full textAbstract:
Les câbles électriques constituent la charge calorifique la plus abondante dans les centrales nucléaires et l'incendie est la source d'agression interne ayant la plus grande occurrence (un départ de feu par tranche et par an en France). Le risque incendie est caractérisé par deux vecteurs : la chaleur dégagée, qui peut conduire à la propagation de l’incendie, et la fumée produite, composée de gaz et d'aérosols, qui peuvent être toxiques et corrosifs et interagir avec les composants présents dans le local. À un stade avancé, un incendie confiné devient sous-ventilé et vicié car la combustion consomme l'oxygène disponible. La production d'imbrûlés augmente donc considérablement, ce qui a pour effet de rendre l'incendie possiblement plus agressif. Pour se protéger des risques d’un incendie confiné, il est donc important de quantifier la chaleur libérée, les gaz et les aérosols produits lors de la combustion de câbles électriques dans des conditions de déplétion d’oxygène. Pour ce faire, un banc expérimental à l'échelle intermédiaire, connu sous le nom de cône calorimètre à atmosphère contrôlée (CCAC), a été développé. Ce banc d’essai a été caractérisé préalablement à l’aide de plaques de PMMA. Des matériaux modèles représentatifs de gaines de câbles électriques à base de PVC ont été formulés puis manufacturés sous forme de plaques échantillons. Ces matériaux ont été caractérisés simultanément en termes de paramètres liés à l'incendie (taux de dégagement de chaleur, perte de masse), de gaz produits et d'aérosols émis, en conditions de sous-ventilation et de viciation à l’aide du couplage CCAC/FTIR/ELPI. La viciation a pour effet de diminuer le débit calorifique et le débit de pyrolyse de façon linéaire, alors que la sous-ventilation favorise la production d’imbrûlées et d’aérosolsElectrical cable sheaths are the most abundant fire load in nuclear power plants and fire is the most frequent internal aggression (one fire outbreak per year and per nuclear unit in France). A fire is threatening by two means: the heat it releases that may drive a fire growth and the smoke it yields, composed of gases and aerosols, that may be toxic and corrosive and interact with components in the area. At advanced stages, confined fires become oxygen depleted and the combustion regime shifts towards under-ventilated and vitiated combustion with the production of unburnt species leading to a higher threat. To assess the potential hazard of a confined fire, it is then of high importance to quantify the heat release, the gases and the aerosols produced by electrical cable sheaths fires in oxygen depleted conditions. To do so, a bench scale apparatus known as the controlled-atmosphere cone calorimeter (CACC) has been developed. The apparatus has been primarily qualified with PMMA plaques. Representative materials of PVC based electrical cable sheath have been formulated and manufactured in the shape of plaque samples. These materials have been characterized in terms of fire parameters (heat release rate, mass loss rate), evolved gases and evolved aerosols under different oxygen concentrations in under-ventilated conditions thanks to the CACC/FTIR/ELPI coupling. Vitiation lowers the heat release rate and decreases the fuel mass loss rate while under-ventilation increases unburnt species and aerosols production
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Chatenet, Sarah. "An instrumented controlled-atmosphere cone calorimeter to characterize electrical cable behavior in depleted fires." Electronic Thesis or Diss., Université de Lille (2018-2021), 2019. http://www.theses.fr/2019LILUR047.
Full textAbstract:
Les câbles électriques constituent la charge calorifique la plus abondante dans les centrales nucléaires et l'incendie est la source d'agression interne ayant la plus grande occurrence (un départ de feu par tranche et par an en France). Le risque incendie est caractérisé par deux vecteurs : la chaleur dégagée, qui peut conduire à la propagation de l’incendie, et la fumée produite, composée de gaz et d'aérosols, qui peuvent être toxiques et corrosifs et interagir avec les composants présents dans le local. À un stade avancé, un incendie confiné devient sous-ventilé et vicié car la combustion consomme l'oxygène disponible. La production d'imbrûlés augmente donc considérablement, ce qui a pour effet de rendre l'incendie possiblement plus agressif. Pour se protéger des risques d’un incendie confiné, il est donc important de quantifier la chaleur libérée, les gaz et les aérosols produits lors de la combustion de câbles électriques dans des conditions de déplétion d’oxygène. Pour ce faire, un banc expérimental à l'échelle intermédiaire, connu sous le nom de cône calorimètre à atmosphère contrôlée (CCAC), a été développé. Ce banc d’essai a été caractérisé préalablement à l’aide de plaques de PMMA. Des matériaux modèles représentatifs de gaines de câbles électriques à base de PVC ont été formulés puis manufacturés sous forme de plaques échantillons. Ces matériaux ont été caractérisés simultanément en termes de paramètres liés à l'incendie (taux de dégagement de chaleur, perte de masse), de gaz produits et d'aérosols émis, en conditions de sous-ventilation et de viciation à l’aide du couplage CCAC/FTIR/ELPI. La viciation a pour effet de diminuer le débit calorifique et le débit de pyrolyse de façon linéaire, alors que la sous-ventilation favorise la production d’imbrûlées et d’aérosolsElectrical cable sheaths are the most abundant fire load in nuclear power plants and fire is the most frequent internal aggression (one fire outbreak per year and per nuclear unit in France). A fire is threatening by two means: the heat it releases that may drive a fire growth and the smoke it yields, composed of gases and aerosols, that may be toxic and corrosive and interact with components in the area. At advanced stages, confined fires become oxygen depleted and the combustion regime shifts towards under-ventilated and vitiated combustion with the production of unburnt species leading to a higher threat. To assess the potential hazard of a confined fire, it is then of high importance to quantify the heat release, the gases and the aerosols produced by electrical cable sheaths fires in oxygen depleted conditions. To do so, a bench scale apparatus known as the controlled-atmosphere cone calorimeter (CACC) has been developed. The apparatus has been primarily qualified with PMMA plaques. Representative materials of PVC based electrical cable sheath have been formulated and manufactured in the shape of plaque samples. These materials have been characterized in terms of fire parameters (heat release rate, mass loss rate), evolved gases and evolved aerosols under different oxygen concentrations in under-ventilated conditions thanks to the CACC/FTIR/ELPI coupling. Vitiation lowers the heat release rate and decreases the fuel mass loss rate while under-ventilation increases unburnt species and aerosols production
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Filion, Jacques. "Distribution spatiale de la regénération d'épinette noire (Picea mariana (Mill.) BSP) 8 ans après un feu de forêt /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1994. http://theses.uqac.ca.
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Cloete, Karen Jacqueline. "Physiological effects of indigenous arbuscular mycorrhizal associations on the sclerophyll Agathosma betulina (Berg.) Pillans." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/16600.
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Thesis (MSc)--University of Stellenbosch, 2005.ENGLISH ABSTRACT: The Mountain Fynbos biome, a division of the Cape Floristic Region (CFR), is home to round-leafed Buchu [Agathosma betulina (Berg.) Pillans], one of South Africa’s best-known endangered herbal medicinal plants. Agathosma betulina is renowned as a traditional additive to brandy or tea, which is used for the treatment of a myriad of ailments. In its natural habitat, A. betulina thrives on mountain slopes in acid and highly leached gravelly soils, with a low base saturation and low concentrations of organic matter. To adapt to such adverse conditions, these plants have formed mutualistic symbioses with arbuscular mycorrhizal (AM) fungi. In this study, the effect of indigenous AM taxa on the physiology of A. betulina is investigated. In addition, the AM taxa responsible for these physiological responses in the plant were identified using morphological and molecular techniques. Agathosma betulina was grown under glasshouse conditions in its native rhizosphere soil containing a mixed population of AM fungi. Control plants, grown in the absence of AM fungi, were included in the experimentation. In a time-course study, relative growth rate (RGR), phosphorus (P)-uptake, P utilization cost, and carbon (C)-economy of the AM symbiosis were calculated. The data showed that the initial stages of growth were characterized by a progressive increase in AM colonization. This resulted in an enhanced P-uptake in relation to non-AM plants once the symbiosis was established. Consequently, the lower P utilization cost in AM plants indicated that these plants were more efficient in acquiring P than non-AM plants. When colonization levels peaked, AM plants had consistently higher growth respiration. This indicated that the symbiosis was resulting in a C-cost to the host plant, characterized by a lower RGR in AM plants compared to non-AM plants. Arbuscular mycorrhizal colonization decreased with increasing plant age that coincided with a decline in P-uptake and growth respiration, along with increases in RGR to a level equal to non-AM plants. Consequently, the AM benefit was only observed during the initial stages of growth. In order to identify the AM fungi in planta, morphological and molecular techniques were employed, which indicated colonization by AM fungi belonging to the genera Acaulospora and Glomus. Phylogenetic analyses of a dataset containing aligned 5.8S ribosomal RNA gene sequences from all families within the Glomeromycota, including sequences obtained during the study, supported the above mentioned identification.
AFRIKAANSE OPSOMMING: Die Fynbos bergbioom, ‘n onderafdeling van die Kaapse Floristiese Streek, huisves rondeblaar Boegoe [Agathosma betulina (Berg.) Pillans], een van Suid Afrika se bekendste bedreigde medisinale plante. Agathosma betulina is bekend vir sy gebruik as tinktuur vir die behandeling van verskeie kwale. Die plant kom voor in bergagtige streke, in suur en mineraal-arm grond, met ‘n lae organiese inhoud. Gevolglik, om aan te pas by hierdie ongunstige kondisies, vorm die plante simbiotiese assosiasies met blaasagtige, struikvormige mikorrisa (BSM). In die huidige studie is die effek van hierdie BSM op die fisiologie van A. betulina ondersoek. Die identiteit van die BSM is ook gevolglik met morfologiese en molekulêre identifikasie tegnieke bepaal. Agathosma betulina plante is onder glashuis kondisies in hul natuurlike grond gekweek, wat ‘n natuurlike populasie van BSM bevat het. Kontroles is ook in die eksperiment ingesluit en hierdie stel plante is met geen BSM geïnokuleer nie. Gevolglik is die relatiewe groeitempo, fosfor opname, fosfor verbuikerskoste asook die koolstof ekonomie van die plante bereken. Die data het getoon dat die eerste groeifase gekarakteriseer is deur toenames in BSM kolonisasie vlakke. Dit het tot ‘n hoër fosfor opname in BSM geïnokuleerde plante gelei. Die laer fosfor verbuikerskoste gedurende hierdie fase het aangedui dat die plante wat geïnokuleer is met BSM oor beter meganismes beskik het om fosfor uit die grond te bekom. Toe BSM kolonisasie vlakke gepiek het, was groei respirasie hoër in BSM geïnokuleerde plante as in die kontroles. Dit het aangedui dat die BSM kolonisasie van plante tot hoër koolstof kostes vir hierdie plante gelei het, wat weerspieël is in die laer groeitempo van die BSM geïnokuleerde plante. Die BSM kolonisasie vlakke het gedaal met toenemende ouderdom van hul gasheer plante, wat gekarakteriseer is deur ‘n laer opname van fosfor en laer groei respirasie, tesame met ‘n toename in relatiewe groeitempo tot vlakke soortgelyk aan die van die kontrole plante. Die BSM voordele vir die plant is dus net gedurende die eerste groeifase waargeneem. Die BSM wat verantwoordelik is vir hierdie fisiologiese veranderinge is gevolglik geïdentifiseer met behulp van morfologiese en molekulêre tegnieke en dit is gevind dat BSM wat behoort tot die genera Acaulospora en Glomus binne hierdie plante voorkom. Filogenetiese analise gegrond op opgelynde 5.8S ribosomale RNA geen volgordes afkomstig van al die families binne Glomeromycota asook volgordes gevind in die studie, het die bogenoemde identifikasie gestaaf.
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Tsitsopoulos, Vasileios. "Modelling of buoyant flows associated with large area fires and indirect free convection." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/modelling-of-buoyant-flows-associated-with-large-area-fires-and-indirect-free-convection(7e849d5b-6b95-4534-b387-63387f5ff26f).html.
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Experimental observations indicate the presence of attached, gravity induced, horizontal buoyant currents above large area fires. Their driving mechanism is indirect and resembles the one observed above heated horizontal plates. Classic plume modelling is satisfactory for providing information for the flow far from the source. In dealing with large areas and directing attention to the flow close to the source, the classic plume theory should fail because the radial pressure gradient that is responsible for the driving of the flow is squeezed in the long and thin classic plume assumption. For this we propose a new plume structure for the description of the buoyant flow above a circular region of large radius L as “The flow field must be divided into three regions. A region where the flow is predominantly horizontal and attached to the surface, a transition region from horizontal to vertical where separation of the attached current takes place, and a region where vertical flow is established and classic plume theory can be applied”. A model for the description of the gross properties of the horizontal currents is developed under the term “horizontal plume”. The modified Richardson number for the horizontal plume a, being analogous to the radius of the large area, is studied asymptotically in the limit a → ∞ and second order uniformly valid semi-analytical solutions are obtained. The hot plate experiment was set up in order to test the model and facilitate its improvement. A chapter is dedicated to the data analysis coming from thermocouple readings and visualisation of the flow using particle image velocimetry.In the remainder of this thesis two classic problems of laminar natural convection are revisited. That of the first order laminar boundary layer above an isothermal circular plate of radius a and the first order laminar boundary layer above the semi- infinite plate inclined to horizontal. In both cases allowances to variable property effects were made through the introduction of a nondimensional parameter λT, with its value set to zero implying the assumption of the Boussinesq approximation. For the circular plate, fourth order series solutions were obtained valid at the edge of the plate where the effects of λT and Prandtl number Pr are studied. Furthermore a finite difference scheme for the numerical solution of the nonsimilar partial integro- differential equation was developed using the Keller Box method and compared with results obtained from the commercial finite element software COMSOL Multiphysics 3.5a. For the semi-infinite plate, fourth order series approximations valid at the edge of the plate were obtained, while an extensive analysis for the effect of λT, Pr and inclination parameter σ was performed on the flow. Positions of the separation points when the inclination is negative (σ < 0) as a function of Pr and λT were recovered.
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Stronach, Neil Richard Hemsworth. "Grass fires in Serengeti National Park, Tanzania : characteristics, behaviour and some effects on young trees." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335247.
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Rackauskaite, Egle. "iTFM : improved travelling fires methodology for structural design and the effects on steel framed buildings." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/52917.
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Accidental fire can be disastrous, especially in buildings. Most fire deaths occur due to the toxic effects of smoke before any structural collapse. However, the effect of fire on structural stability is critical in regard to safe evacuation and safe access for fire-fighters, financial losses, and lost business. This is particularly the case in tall buildings where extended evacuation times are required due to phased evacuation practises. The understanding of fundamental mechanisms of whole building behaviour in fire has significantly increased over the last decades, in particular after the full-scale tests of various multi-storey buildings carried out in Cardington between 1994 and 1999. However, most of the current understanding and consequently the design codes are based on the assumption of uniform fire conditions in a compartment. While this assumption may be suitable for small enclosures, fires in large open-plan compartments have been observed to travel. Examples of such fires include the World Trade Centre Towers 1, 2 & 7 (2001), Windsor Tower fire in Madrid (2006) and the recent fire at the Plasco building in Tehran (Jan 2017). All of these buildings ultimately either partly of fully collapsed. Current design standards do not account for travelling fires. The standard and parametric time-temperature curves are based on small scale tests, and assume uniform burning of fire and homogeneous temperature distributions in a compartment. In the recent years a new design concept of the Travelling Fires Methodology (TFM) has been developed by G. Rein to account for the travelling nature of fires in large compartments. This design methodology considers non-uniform temperature distribution in the compartment and a wide range of burning floor areas. In this thesis the Travelling Fires Methodology is improved to account for more realistic fire dynamics and then applied to investigate the structural response of a multi-storey steel frame using finite element software LS-DYNA. This thesis is presented in a manuscript style: each chapter takes the form of an independent paper, which has been published or submitted to a journal for publication. A final chapter summarizes the conclusions, and suggests potential areas of future research. Firstly, an improved Travelling Fires Methodology (iTFM) that accounts for better fire dynamics is presented in Chapter 2. Equations are introduced to reduce the range of possible fire sizes taking into account fire spread rates from real fires. The analytical equations used to represent the far-field temperatures are presented in continuous form. The concept of flame flapping is introduced to account for variation of temperatures in the near-field region due to natural fire oscillations. iTFM is then used to analyse the effect of non-uniform heating associated with travelling fires on the thermal response of structural members and identification of the location of peak temperature along the fire path. It is found to be mainly dependent on the fire spread rate and the heat release rate. Location of the peak temperature in the compartment is found to mostly occur towards the end of the fire path. Full-scale testing of real structures is complex, expensive and time consuming. This is especially the case for structures with large compartments. There has only been a limited number of full-scale tests on real buildings carried out worldwide (e.g. Cardington tests). As a result, computational tools are commonly used to assess the structural response of complex buildings under fire conditions. However, they have to be validated first. Therefore, in Chapter 3, prior to the study of the effects of iTFM on the structural response, explicit solver of finite element software LS-DYNA used for the analyses in Chapters 4-7 is benchmarked for structural fire analyses against other static numerical codes and experiments. Four canonical problems that encompass a range of thermal and mechanical behaviours in fire are simulated. The parameter sensitivity study is carried out to study the effects of various numerical parameters on the convergence to quasi-static solutions. The results confirm that when numerical parameters are carefully considered not to induce excessive inertia forces in the system, explicit dynamic analysis using LS-DYNA provide good predictions of the key variables of structural response during fire. Finally, the structural response of a two-dimensional multi-storey steel frame subjected to uniform design fires and iTFM (presented in Chapter 2) occurring on a single floor and multiple floors is investigated in Chapters 4, 5, & 7, and Chapters 6 & 7, respectively. Fire type and the location of the fire floor in the frame are varied. The analyses and comparison of structural response mechanisms is presented in Chapter 4. Uniform fires are found to result in higher compressive axial forces in beams compared to small travelling fires. However, results show irregular oscillations in member utilization levels in the range of 2 - 38% for the smallest travelling fire sizes, which are not observed for the uniform fires. Beam mid-span deflections are similar for both travelling fires and uniform fires and depend mainly on the fire duration, but the locations in the frame where these displacements occur are found to be different. Chapter 5 extends the study presented in Chapter 4 and compares the results in the terms of the limiting temperature criteria and various structural limit states. Critical fire scenarios are found to occur on the upper floors of the frame where column sections reduce in size. Also, results show that depending on the fire scenario higher level of fire protection for different members within the frame may lead to either enhanced or worse structural response and/or resistance. During previous fire events, e.g. the World Trade Centre Towers (WTC) 1, 2 & 7 in New York (2001), flames were observed to not only travel horizontally across the floor plate but also vertically to different floors. In this thesis, the effect of vertically travelling and multiple floor fires on the structural response of a two-dimensional multi-storey steel frame is investigated in Chapter 6. The number of fire floors, and horizontal and vertical fire spread are varied. Results show that the largest stresses develop in the fire floors adjacent to cool floors, and their behaviour is independent of the number of fire floors. All, the fire type, the number of fire floors, and the location of the fire floor, are found to have a significant effect on the failure time (i.e. exceeded element load carrying capacity) and the type of collapse mechanism (Chapter 7). In the cases with a low number of fire floors (1 to 3) failure is dominated by the loss of material strength, while in the cases with larger number of fire floors (5 to 10) failure is dominated by thermal expansion. Collapse is observed to be mainly initiated by the pull-in of external columns or swaying of the frame to the side of fire origin. Analyses presented in Chapters 4 to 7 highlight that in the structural design for fires it is important to consider more realistic fire scenarios associated with travelling fires as they might trigger previously unnoticed structural mechanisms. Results on the multi-storey steel frame indicate that, depending on the structural metric examined, both travelling fires and uniform fires can be more severe than the other. A single worst case fire scenario under which a structure could be designed and deemed to be safe cannot be established. For different fire exposures failure is found to occur on different range of floors subjected to fire. Therefore, in order to ensure a safe fire resistance design of buildings with large enclosures, a range of different fires including both travelling fires and uniform fires need to be considered.