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1
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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Díaz, Avalos Carlos. "Space-time analysis of forest fires /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/6375.
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Brown, Sara H. "Modeling the spatial distribution of lightning fires on two national forests." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Summer2009/s_brown_062109.pdf.
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Thesis (M.S. in environmental science)--Washington State University, August 2009.<br>Title from PDF title page (viewed on Sept. 15, 2009). "School of Earth and Environmental Sciences." Includes bibliographical references (p. 54-56).
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Chau, Kam-chiu Lawrence. "The ecology of fire in Hong Kong /." Hong Kong : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18933798.
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Candy, Katherine. "Mapping fire affected areas in northern Western Australia - towards an automatic approach." Candy, Katherine (2004) Mapping fire affected areas in northern Western Australia - towards an automatic approach. Masters by Research thesis, Murdoch University, 2004. http://researchrepository.murdoch.edu.au/500/.
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Wildfires across northern Australia are a growing problem with more than 2.5 million hectares being burnt each year. Accordingly, remote sensing has been used as a tool to routinely monitor and map fire histories. In northern Western Australia, the Department of Land Information Satellite Remote Sensing Services (DLI SRSS) has been responsible for providing and interpreting NOAA-AVHRR (National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer) data. SRSS staff utilise this data to automatically map hotspots on a daily basis, and manually map fire affected areas (FAA) every nine days. This information is then passed on to land managers to enhance their ability to manage the effects of fire and assess its impact over time.
The aim of this study was to develop an algorithm for the near real-time automatic mapping of FAA in the Kimberley and Pilbara as an alternative to the currently used semimanual approach. Daily measures of temperature, surface reflectance and vegetation indices from twenty nine NOAA-16 (2001) passes were investigated. It was firstly necessary to apply atmospheric and BRDF corrections to the raw reflectance data to account for the variation caused by changing viewing and illumination geometry over a cycle.
Findings from the four case studies indicate that case studies 1 and 2 exhibited a typical fire response (visible and near-infrared channels and vegetation indices decreased), whereas 3 and 4 displayed an atypical response (visible channel increased while the near-infrared channel and vegetation indices decreased). Alternative vegetation indices such as GEMI, GEMI3 and VI3 outperformed NDVI in some cases. Likewise atmospheric and BRDF corrected NDVI provided better performance in separating burnt and unburnt classes.
The difficulties in quantifying FAA due to temporal and spatial variation result from numerous factors including vegetation type, fire intensity, rate of ash and charcoal dispersal due to wind and rain, background soil influence and rate of revegetation. In this study two different spectral responses were recorded, indicating the need to set at least two sets of thresholds in an automated or semi-automated classification algorithm. It also highlighted the necessity of atmospheric and BRDF corrections.
It is therefore recommended that future research apply atmospheric and BRDF corrections at the pre-processing stage prior to analysis when utilising a temporal series of NOAAAVHRR data. Secondly, it is necessary to investigate additional FAA within the four biogeographic regions to enable thresholds to be set in order to develop an algorithm. This algorithm must take into account the variation in a fire's spectral response which may result from fire intensity, vegetation type, background soil influence or climatic factors.
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Dell'Orfano, Michael E. "Fire Behavior and Fuel Modeling of Flammable Shrub Understories in Northeastern Pine-Oak Forests." Digital WPI, 2004. https://digitalcommons.wpi.edu/etd-theses/1070.
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"This thesis evaluates the effectiveness of BEHAVE: Fire Behavior Prediction and Fuel Modeling System in predicting fire behavior in the Northeastern pine-oak forest. This fuel complex is composed primarily of a litter and huckleberry shrub understory with a pitch pine and oak overstory. Measurements of fuel bed physical characteristics, weather and fire behavior are taken from a series of prescribed burn studies in Cape Cod National Seashore in Massachusetts. Site-specific fuel models are constructed which provide the necessary inputs for fire predictions. Observed spread rates and flame lengths are over-predicted by BEHAVE for burns conducted during the winter (dormant season) and under-predicted for burns conducted during the summer (growing season). Attempts to improve winter predictions are successful when the litter moisture is adjusted in order to account for the live wintergreen which increases the overall moisture content of the surface fuels. A sensitivity study is performed where each input parameter is varied over a reasonable interval in order to view its impact on predictions. The model’s high sensitivity to fuel bed depth and 1-hr surface-area-to-volume ratio appear to be the cause for fire prediction deviations during the winter, while the high live fuel moisture contents appear to overwhelm and suppress fire behavior predictions during the summer. It is concluded to overwhelm and suppress fire behavior predictions during the summer. It is concluded that BEHAVE’s representation of fuel complexes as a homogeneous fuel bed with constant properties does not take into account the unique features of the litter and shrub components. An alternative, simple model of fire spread is developed which treats each component as a separate fuel bed. The model is based on a measurement of the heat release rate which can be determined directly through the principle of oxygen consumption calorimetry. Future work using small- and large- scale testing apparatus will help determine the ignition process of the live shrubs and the effect of parameters such as moisture content on the burning characteristics of the fuels. "
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Wang, Wanting. "Satellite remote sensing of forest disturbances caused by hurricanes and wildland fires." Fairfax, VA : George Mason University, 2009. http://hdl.handle.net/1920/4579.
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Thesis (Ph.D.)--George Mason University, 2009.<br>Vita: p. 151. Thesis director: John J. Qu. Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Earth Systems and Geoinformation Sciences. Title from PDF t.p. (viewed Oct. 11, 2009). Includes bibliographical references (p. 136-150). Also issued in print.
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Cochrane, Jared Douglas. "Characteristics of historical forest fires in complex mixed-conifer forests of southeastern British Columbia." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31644.
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Forest fires in southeastern British Columbia are considered the dominant natural disturbance to have shaped forest structure. In the mixed conifer montane forests of the Dry Cool Montane Spruce (MSdk) biogeoclimatic subzone, we have limited understanding of the characteristics of fire which have resulted in current forest structure. A better understanding of fire in these forests is needed to improve forest management and ecosystem restoration strategies which seek to emulate natural disturbance. To assess the historic role of fire in mixed conifer forests and to test the null hypothesis that fires do not vary spatially or temporally, this study uses cambial fire scars to analyze the historic frequency of fire in 20 stands that are statistically representative of complex, mixed-conifer forests in the southern Rocky Mountain Trench of British Columbia. Determining the date of cambial injury on a tree is an important objective of ecological research that determines the timing of disturbances such as fire, tree falls, or human modification of trees. Methods to determine scar dates require either a full stem cross-section or a partial cross-section of the wounded area. The latter method is less destructive however it is rarely used in British Columbia due to potential violations of established standard of care procedures regarding wildlife and danger trees. I developed procedures and protocols that provide a standard of care that was reviewed by WorkSafeBC and found to meet the intent of the Occupational Health and Safety Regulations ensuring the health and safety of workers. These procedures allow large, old trees of interest to researchers to contribute to the ecosystem over the long term and prevent the creation of dangerous trees that may threaten the safety of other forest users, making a valuable contribution to future research using cambial injuries in British Columbia. Spatial variation in fire is an important driver of forest heterogeneity at the stand and landscape scale. Using cambial fie scars on trees sampled at 20 study sites, I determined that fire frequency varied considerably between and among studied plots. I expected fires would be more frequent in plots with southern aspects than northern aspect plots. Instead, using logistic regression, I found fires to be more frequent on plots with northern aspects plots than southern aspect plots. Plot elevation, slope angle and solar radiation significantly influenced fire frequency, while plot aspect and latitude did not. Differences in season of fires were predominantly the result of differences in phenology between the two most commonly sampled tree species, Douglas-fir (Pseudostuga menzeisii var glauca (Beissn.) Franco) and western larch (Larix occidentalis Nutt.). Temporally, fire was most frequent during the time period of documented European settlement and the least frequent during the modern fire suppression period. My research results have important implications for forest management strategies which emulate natural disturbance to promote ecological resilience. Historically, fire occurred in the complex montane forests at much higher frequency than is currently classified using the Natural Disturbance Types (NDT). As a result, forest management strategies are likely preventing the occurrence of low- to moderate-severity disturbances in these forests, reducing their ecological resilience. Future management strategies should incorporate the variability observed in this study at the stand and landscape scales and return low- to moderate severity disturbances to these stands more frequently. Ecosystem restoration in these forests should be prioritized on stands that have deviated the most from the historic frequency of fires; particularly in stands which are at lower elevations and closer to valley bottom of the Rocky Mountain Trench.<br>Arts, Faculty of<br>Geography, Department of<br>Graduate
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Shrestha, Hari Ram. "Post-fire recovery of carbon and nitrogen in sub-alpine soils of South-eastern Australia /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/6963.
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The forests of south-eastern Australia, having evolved in one of the most fire-prone environments in the world, are characterized by many adaptations to recovery following burning. Thus forest ecosystems are characterized by rapid regenerative capacity, from either seed or re-sprouting, and mechanisms to recover nutrients volatilized, including an abundance of N2 fixing plants in natural assemblages. Soil physical, chemical and biological properties are directly altered during fire due to heating and oxidation of soil organic matter, and after fire due to changes in heat, light and moisture inputs. In natural ecosystems, carbon (C) and nitrogen (N) lost from soil due to fires are recovered through photosynthesis and biological N2 fixation (BNF) by regenerating vegetation and soil microbes.<br>This study investigated post-fire recovery of soil C and N in four structurally different sub-alpine plant communities (grassland, heathland, Snowgum and Alpine ash) of south-eastern Australia which were extensively burnt by landscape-scale fires in 2003. The amount and isotopic concentration of C and N in soils to a depth of 20 cm from Alpine ash forest were assessed five years after fire in 2008 and results were integrated with measurements taken immediately prior to burning (2002) and annually afterwards.<br>Because the historical data set, comprised of three soil samplings over the years 2002 to 2005, consisted of soil total C and N values which were determined as an adjunct to 13C and 15N isotopic studies, it was necessary to establish the accuracy of these IRMS-derived measurements prior to further analysis of the dataset. Two well-established and robust methods for determining soil C (total C by LECO and oxidizable C by the Walkley-Black method) were compared with the IRMS total C measurement in a one-off sampling to establish equivalence prior to assembling a time-course change in soil C from immediately pre-fire to five years post-fire. The LECO and IRMS dry combustion measurements were essentially the same (r2 >0.99), while soil oxidizable C recovery by the Walkley-Black method (wet digestion) was 68% compared to the LECO/IRMS measurements of total C. Thus the total C measurement derived from the much smaller sample size (approximately 15 mg) combusted during IRMS are equivalent to LECO measurement which require about 150 mg of sample.<br>Both total C and N in the soil of Alpine ash forests were significantly higher than soils from Snowgum, heathland and grassland communities. The ratio of soil NH4+ to NO3- concentration was greater for Alpine ash forest and Snow gum woodland but both N-fractions were similar for heathland and grassland soils. The abundance of soil 15N and 13C was significantly depleted in Alpine ash but both isotopes were enriched in the heathland compared to the other ecosystems. Abundance of both 15N and 13C increased with soil depth.<br>The natural abundance of 15N and 13C in the foliage of a subset of non-N2 fixing and N2 fixing plants was measured as a guide to estimate BNF inputs. Foliage N concentration was significantly greater in N2 fixers than non-N2 fixers while C content and 13C abundance were similar in both functional groups. Abundance of 15N was depleted in the N2 fixing species but was not significantly different from the non-N2 fixers to confidently calculate BNF inputs based on the 15N abundance in the leaves.<br>The total C pool in soil (to 20 cm depth) had not yet returned to the pre-fire levels in 2008 and it was estimated that such levels of C would be reached in another 6-7 years (about 12 years after the fire). The C and N of soil organic matter were significantly enriched in 15N and 13C isotopes after fire and had not returned to the pre-fire levels five years after the fire. It is concluded that the soil organic N pool can recover faster than the total C pool after the fire in the Alpine ash forests.
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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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Bjervig, Joel, and Johan Slagbrand. "Thermal Imaging Platform for Drones : Cost-effective localization of forest fires." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385834.
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A device for identifying forest fires in an early stage has been developed during the course of this project. Attached to a drone, this prototype will provide a live-stream to a web server displaying a blended frame, made of a thermographic image showing thermal radiation and a regular photography with the visible light. The platform consists of a small single-boarded computer, a thermal camera sensor and a regular camera module. All powered by a power bank and fitted into a custom made 3D printed plastic case. At startup the computer automatically executes scripts written in Python, initializing its sensor components and processes the captured images which finally gets transmitted to a live-stream via a web server connection. Everything described above worked well, but originally the intent was for the web interface to provide a map with the current location coordinates of the drone. Since a module for mobile communication with support for GPS was not acquired, any implementation of such kind was impossible. However, several drone models already possess the feature to obtain such coordinates.
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González, Tagle Marco Aurelio. "Fire history and natural succession after forest fires in pine-oak forests an investigation in the Ecological Park "Chipinque", Northeast Mexico /." [S.l.] : [s.n.], 2005. http://webdoc.sub.gwdg.de/diss/2005/gonzalez_tagle.
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Berkley, Evelyn L. "Temporal and spatial variability of fire occurrence in Western Oregon, A.D. 1200 to present /." view abstract or download file of text, 2000. http://wwwlib.umi.com/cr/uoregon/fullcit?p1402785.
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Thesis (M.S.)--University of Oregon, 2000.<br>Computer optical disc in pocket of back cover titled: Animated time series of fire occurrence in Western Oregon, A.D. 1200-2000. Typescript. Includes vita and abstract. Includes bibliographical references (leaves 107-110). Also available for download via the World Wide Web; free to UO users.
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Archibald, Robert D. "Fire and the persistence of tuart woodlands /." Access via publisher's site, 2006. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20071130.140115.
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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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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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Lorenzo, Díaz María del Carmen. "La economía de los incendios forestales Modelos de ocurrencia y de asignación de recursos /." Online version, 1998. http://bibpurl.oclc.org/web/13294.
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Luisi, Domenico. "Conceptual design and specification of a microsatellite forest fire detection system /." Online version of thesis, 2007. http://hdl.handle.net/1850/5771.
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Sagra, Javier, Daniel Moya, Pedro Plaza-Álvarez, et al. "Predation on Early Recruitment in Mediterranean Forests after Prescribed Fires." MDPI AG, 2017. http://hdl.handle.net/10150/625399.
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Wildfires play a significant role in many different elements of Mediterranean forest ecosystems. In recent years, prescribed fires have started being used more often as a fuel reduction tool, and also as silvicultural treatment to help the regeneration and health improvement of stands. Apart from the fact that fire may alter microsite conditions, very little is known about the impact of prescribed burning on natural regeneration or plant species renewal in Mediterranean pine forests. Likewise, knowledge about the influence of seedling predators on post-fire regeneration is still scarce. In this study, we aimed to compare the effects of seedling predation on recruitment in earlier stages after prescribed burnings in three pine stands in Central Spain: a pure stand of Pinus nigra; a mixed stand of Pinus halepensis and Pinus pinaster and a mixed stand P. nigra with P. pinaster. In situ we superficially sowed seeds from two different species. In the sowing experiment, we tested two different seed provenances (drier and more humid spanish regions) for each species. In all, 60 plots (30 burned, 30 unburned) per site, with 10 seeding units per plot and more than 20,000 seeds, were used in the whole study. Seedling predation was evaluated by replicating the seeding units inside and outside a wire cage as protection for rodents and birds. Our results showed that prescribed fires alter initial seedling predation intensity: predation was significantly higher in the seedlings grown in the plots affected by prescribed fire. The individuals sown before the fire passed showed slightly more predation than those sown after fire passage. Provenances did not appear as an important predation drive. Understanding the role of the predation associated with these treatments can help improve Mediterranean pine forest management.
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Gilreath, John M. "Validation of variables for the creation of a descriptive fire potential model for the Southeastern Fire District of Mississippi." Master's thesis, Mississippi State : Mississippi State University, 2006. http://library.msstate.edu/etd/show.asp?etd=etd-06152006-135531.
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Le, Canut Philippe. "Forest Fires in Western Europe in 1987." W&M ScholarWorks, 1993. https://scholarworks.wm.edu/etd/1539625803.
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Owusu-Afriyie, Kennedy. "Forest fire incidence, damage and control measures in Ghana." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2008. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26030.
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Gavin, Daniel Girard. "Holocene fire history of a coastal temperate rain forest, Vancouver Island, British Columbia, Canada /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/5477.
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Heyerdahl, Emily K. "Spatial and temporal variation in historical fire regimes of the Blue Mountains, Oregon and Washington : the influence of climate /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/5575.
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Mueller, Joshua Robert. "The relative controls on forest fires and fuel source fluctuations in the Holocene deciduous forests of southern Wisconsin, USA." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/15679.
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Master of Arts<br>Department of Geography<br>Kendra K. McLauchlan<br>Reconstructing fire regimes and fuel characteristics is an important aspect of understanding past forest ecosystem processes. Fuel sources and disturbance regimes throughout the upper Midwestern United States have been shown to be sensitive to regional climatic variability such as drought periods on millennial timescales. Yet, records documenting the complex connections between disturbance activity and the corresponding fuel source fluctuations in mesic deciduous forests and oak savanna forests in this region are limited. Thus, it has been difficult to provide a framework to evaluate drought conditions on fire activity and the relationships with fuel source fluctuations in this region. Here, I conducted high-resolution charcoal analyses of lake sediments from four sites in southeastern-southcentral Wisconsin (USA) to characterize fire activity and fuel source fluctuation in mesic deciduous forests and prairie-oak savanna over the last 10,000 years. I found that fire regimes across the four study sites have been asynchronous throughout the Holocene, due to site-specific differences that have strongly influenced local fire regimes. I also found that during periods of high fire activity the primary fuels were from arboreal sources, and during periods of low fire activity the primary fuels were from non-arboreal sources. However, fluctuations in fuel sources did not always correspond to changes in vegetation, or changes in fire frequency.
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Vasconcelos, Maria 1963. "Simulation of fire behavior with a geographic information system." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/558097.
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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.<br>Forestry, Faculty of<br>Graduate
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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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Agarwal, Jutshi. "Application of Fuzzy Logic for Enhanced Situational Awareness of Surface Wildfires." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1511856508378518.
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Ofren, Rey S. "Spatial Assessment and Hazard Modeling of Tropical Forest Fires." Thesis, University of Auckland, 1999. http://hdl.handle.net/2292/1103.
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This research study offers a quantitative understanding of the environmental factors related to fire occurrence and its potential distribution. The Huai Kha Khaeng Wildlife Sanctuary, located in the northwestern region of Thailand, serves as an example to analyze and expand the knowledge base of forest fire ecology in tropical environments. Specific objectives focus on establishing the relationship between physiognomic variables that are related to forest fuel loading among different forest types. In addition, this study aims at modeling and quantifying the relative importance of the biophysical variables associated with the occurrence of tropical forest fires. The methodological framework links Geographic Information Systems (GIS) with the potential of statistical analysis. Thematic layers of several biophysical variables are combined in GIS, along with field measurements of fuel loading and stand physiognomy. Under the statistical analysis, the variability and interactions of spatial attributes related to fires are synthesized using the Decision Tree modeling. GIS is further employed to display the modeling results. Rainfall pattern, geological material, aspect and vegetation index variables significantly influence the ability of the Decision Tree model to predict the likely occurrence of fire. They explain most of the processes underlying a hierarchical set of rules that help to distinguish the varying levels of fire hazards. The vegetation index in particular was found to be a strong potential indicator of fire incidents and an underlying driving factor behind fuel moisture dynamics. At a certain vegetation index, two types of forest were distinguished as having wet and dry fuel conditions. The difference in the amount of fuel load between the physiognomically distinct evergreen and deciduous forests is proven to be insignificant, except in the variation of moisture content. Factors contributing to the varying levels of fuel moisture in evergreen forests are controlled by the micro-climate created by its intact crown cover. However, there is no distinct relationship concerning the stand structure of deciduous forest with regard to the dryness of fuel on its floor. The dominance of weather over the fuel variables suggests that forest fire situations in an open and dry stand of deciduous forest is driven by extreme weather conditions. A GlS-generated map of the sanctuary illustrates the spatial variation in fire hazard probabilities as predicted by the Decision Tree model. The prediction accuracy of fire hazard zones based on bio-physical factors is further enhanced by incorporating the proportion of neighbouring areas with high potential for ignition. The potential combustibility and danger rating are determined for the predicted hazard zones. In addition, the spatial association of the neighbouring human settlements is analyzed. This research expands the value of GIS from the usual selective retrieval and investigation of spatial patterns into the evaluation of the complex hierarchical combinations of spatial attributes. The combined effect of GIS and statistical modeling eliminates the problems of handling a mixture of environmental data and identifying both variables and attributes interactions. Likewise, the need to design site-specific fire managemet strategies, as guided by particular combinations of environmental attributes, takes into account the applicability of the data-driven Decision Tree modeling. Keywords: fire hazard modeling, fire management, GIS, Decision Tree analysis, Thailand.
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Carvalho, Anabela Victorino. "Forest fires and air quality under a climate change scenario." Doctoral thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/700.
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Doutoramento em Ciências Aplicadas ao Ambiente<br>Os incêndios florestais e a qualidade do ar em cenário de alteração climática
constituem uma das maiores ameaças ao desenvolvimento sustentável.
Nestes sentido, este trabalho pretende avaliar o impacte das alterações
climáticas nos incêndios florestais e na qualidade do ar.
A análise estatística de doze distritos Portugueses revelou que a meteorologia
e as componentes do índice Canadiano de risco de incêndio são as variáveis
que determinam os números dos incêndios florestais em Portugal. Neste
âmbito, este trabalho pretendeu também caracterizar os padrões atmosféricos
associados à ocorrência dos incêndios florestais. Com base numa análise
estatística com desfasamento temporal (lagged correlation) concluiu-se que a
ocorrência de grandes incêndios é precedida por transporte de ar quente e
seco do centro da Península Ibérica para Portugal.
De forma a avaliar o impacte das alterações climáticas nos incêndios florestais
estimou-se o índice meteorológico de risco de incêndio para o cenário SRES
A2 do IPCC para duas resoluções espaciais, 12 km e 25 km. A análise permitiu
concluir que num cenário de alteração climática o risco de incêndio sofrerá um
agravamento significativo, principalmente nos distritos do Norte e Centro do
país. Com base nesta análise e nas relações estatísticas estabelecidas entre
os incêndios florestais e a meteorologia foi possível prever a área ardida e o
número de incêndios em clima futuro. Os distritos de Bragança e Porto
poderão ser os mais afectados em termos de aumento da área ardida. As
projecções indicam que no final do século XXI a área ardida e o número de
incêndios em Portugal poderão aumentar cerca de 500 % e 300 %,
respectivamente, relativamente aos anos 80.
Com base nas projecções de área ardida em clima futuro estimaram-se as
emissões provenientes dos incêndios florestais e avaliou-se o seu potencial
impacte na qualidade do ar. O impacte das alterações climáticas e dos
incêndios florestais nos níveis de ozono e partículas foi avaliado através da
aplicação do sistema de modelação MM5/CHIMERE. As projecções indicam
que a alteração climática contribui para o aumento dos níveis de ozono na
atmosfera em cerca de 20 µg m-3. Se a emissão dos incêndios florestais em
clima futuro também for considerada poderá verificar-se uma redução das
concentrações de ozono na imediação dos incêndios florestais e um aumento
a jusante. Os níveis de partículas na atmosfera sofrerão aumentos mas
também serão detectadas diminuições em determinadas regiões.
Neste trabalho desenvolveu-se uma ferramenta científica inovadora que ajuda
a fundamentar decisões políticas e estratégias de combate e mitigação do
impacte das alterações climáticas nos incêndios florestais e na qualidade do
ar.<br>Forest fire activity and air quality under a changing climate are considered one
of the main threats to sustainable development. The interaction between the
climate, the forest fire activity and the air quality over Portugal is the main
purpose of this study.
The relationship between the weather, the fire weather risk and the forest fire
activity has been assessed for twelve districts over Portugal. Statistical
significant correlations have been established among the analysed variables
indicating the weather as the most important natural factor influencing forest
fires in Portugal. In order to better assess the role of the regional scale
atmospheric conditions in fire activity, the typical structural evolution of the
atmospheric field patterns in a wildfire event was investigated by lagged
analysis. The analysis pointed out that in the pre-phase of a forest fire event
heated air is transported from the Iberian Peninsula’s centre towards Portugal.
Having in mind the important role of the atmospheric conditions on fire activity
statistics over Portugal, the fire weather under the IPCC SRES A2 scenario
was assessed for two spatial resolutions, 12 km and 25 km. A substantial
increase on the future fire weather risk over Portugal especially in the inner
districts of the North and Centre is expected.
Taking into account that the weather explains the majority of the forest fire
activity in Portugal and based on the fire weather projections under future
climate it was possible to forecast future area burned and number of forest
fires. The projections showed a substantial increase on the area burned namely
in Bragança and Porto districts. By the end of the XXI century, Portugal may
face increases of approximately 500 % and 300 % for area burned and number
of fires, respectively, comparatively to the 80s.
Based on the future area burned projections it was possible to estimate future
fire emissions and to evaluate their impact on air quality. The MM5/CHIMERE
air quality modelling system was applied to the reference and to the future
climate scenarios. The projected impacts pointed that climate change alone
enhances the ozone levels in the atmosphere of up to 20 µg m-3. When forest
fire emissions are also considered the ozone levels decrease in the vicinity of
the forest fires but increase downwind of their locations. The particulate matter
in the atmosphere will increase but decreases may also be detected.
This study constitutes an innovative scientific tool that helps to fundament
strategies and policies to face and mitigate future climate change impacts on
forest fire activity and air quality.
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Holt, Ryan Samuel. "Three enabling technologies for vision-based, forest-fire perimeter surveillance using multiple unmanned aerial systems /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1894.pdf.
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Malmström, Anna. "Effects of wildfire and prescribed burning on soil fauna in boreal coniferous forests /." Uppsala : Department of Ecology and Environmental Research, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/2006111.pdf.
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Van, der Sijde J. H. R. (Jan Herman Robert). "The assessment of fire history in plantations of Mpumalanga North." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53616.
Full textAbstract:
Thesis (MScFor) -- Stellenbosch University, 2003.<br>ENGLISH ABSTRACT: Fire is a threat to all forest plantations. As a result, growers are forced to take active
measures to reduce the incidence and extent of fires in their plantations.
This thesis is an attempt to collate 846 fire records for eight Komatiland Forests
(KLF) plantations in Mpumalanga North for the period 1950 to 1999. Up to now,
these reports and the information therein, were not utilised by KLF for planning or for
evaluating fire management practices. The only other studies in South Africa, using
similar data, were conducted by LeRoux (1988) and Kromhout (1990).
A brief background of the forestry industry in South Africa, and in particular
Mpumalanga is presented. The main text of the report covers a presentation on fire
causes, extent of damage (both in area and in Rand value) and various aspects
related to time of ignition and response times. A detailed analysis was done to
identify possible relationships between the variables related to compartment, climate
and different fire suppression activities.
A cause and frequency prediction model was developed that will assist fi re managers
in identifying and determining probabilities of fires per cause. Statistical guidelines
regarding the planning of fire management around fires caused by honey hunters,
lightning, work-related factors, and the activities of people (public, own labour,
contractors) are presented.
Conclusions were drawn from the results of the analyses of the fire data, which
covered a period of 47 years. Recommendations regarding guidelines for strategic
fi re management for the Mpumalanga North plantations were made. The main
conclusions are:
• Statistics on previous fires are very useful in fire management planning
as it supplies valuable information on fire causes, time of ignition , past
performance related to response times, fire fighting times and damaged
caused.
•
•
•
•
The average area lost due to fires in the study area is 209.9 ha or
0.43% of the plantation area per annum.
People-related fires (arson, smokers, picnickers, children and
neighbours) caused most of the wild fires (48%), followed by lightning
(22%).
Some plantations performed poorly, with the occurrence of up to
double the number of fires per 1 000 ha of plantation compared to other
plantations in the same geographic area.
There are definite patterns in the frequency of fires per cause with
month of the year. These patterns are valuable for the development of
strategies to manage fires caused by honey hunters, lightning fires and
work-related fires.<br>AFRIKAANSE OPSOMMING: Brande is 'n bedreiging vir aile bosbou plantasies. Dit is dus noodsaaklik dat
kwekers maatreeHs tref om die voorkoms en omvang van brande in plantasies te
beperk.
Hierdie tesis poog om 846 vuurverslae se inligting te ontleed ten opsigte van agt
Komatiland Forests (KLF) plantasies in Mpumalanga Noord vir die tydperk 1950 tot
1999.
Tot op hede is min van die inligting wat in die verslae vervat is deur KLF vir
beplanning- en evalueringsdoeleindes ten opsigte van brandbestuur gebruik. Die
enigste soortgelyke studies wat op brandverslagdata in Suid-Afrika gedoen is, is
gedoen deur Le Roux (1988) en Kromhout (1990).
'n Kort agtergrond oor die bosbouindustrie in Suid-Afrika en spesifiek Mpumalanga
word gegee. Die tesis gee 'n oorsig oor brandoorsake, skade wat deur brande
veroorsaak word (oppervlakte sowel as finansieHe waarde) en verskeie aspekte
rakende brandbestuur soos tyd van ontstaan en reaksietye. Data is volledig ontleed
om moontlike verwantskappe te probeer vind tussen vak-, klimaat- en
brandbestuursveranderlikes.
'n Oorsaak- en frekwensievoorspellingsmodel is ontwikkel wat brandbestuurders sal
help om waarskynlikhede van brande per oorsaak te identifiseer. Statistiese riglyne
ten opsigte van bestuursbeplanning vir weerligvure, brande deur heuninguithalers,
brande as gevolg van plantasiewerksaamhede en ook brande deur mense (publiek,
eie arbeid en kontrakteurs) is daargestel.
Brandrekords wat oor 'n periode van 47 jaar gestrek het, is ontleed. Afleidings wat
uit die resultate gemaak is, kan benut word om riglyne daar te stel vir strategiese
brandbestuur in Mpumalanga Noord plantasies. Die hoof gevolgtrekkings is:
• Statistiek van vorige vure is baie nuttig in brandbestuursbeplanning
aangesien dit waardevolle inligting verskaf oor brand oorsake, tyd van ontstaan, historiese werkverrigting rakende reaksietye en blustye,
sowel as skade wat veroorsaak is.
Die gemiddelde oppervlakte beskadig in die studie area is 209.9 ha, of
0.43% van die plantasie oppervlakte per jaar.
Menslike aktiwiteite (brandstigting, rakers, piekniekvure, kinders en
vure van bure) het die meeste brande veroorsaak (48%), gevolg deur
weerlig (22%).
Sommige plantasies het swak gevaar en het tot soveel as dubbel die
aantal vure per 1 000 ha plantasie gehad in vergelyking met ander
plantasies in dieselfde geografiese gebied.
Daar is duidelike patrone gevind in die frekwensie van brande per
oorsaak oor maande van die jaar. Hierdie patrone is nuttig vir die
ontwikkeling van bestuurstrategie vir brande wat veroorsaak word deur
heuningversamelaars, weerlig en werkverwante aktiwiteite (plantasieaktiwiteite).
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Vicenza, Sarah Dalla, and University of Lethbridge Faculty of Arts and Science. "Forest vulnerability to fire in the northern Rocky Mountains under climate change." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, 2012. http://hdl.handle.net/10133/3422.
Full textAbstract:
Forest fires are an increasing concern under climate change. Substantially increased fire vulnerability could become a reality for many areas, including the Rocky Mountains. Forest fire hazard was examined in the upper North Saskatchewan and St. Mary watersheds for the period of 1960 to 2100. Ensemble climate scenarios were chosen to represent a wide range of possible future climates. The GENGRID meteorological model and the Canadian Forest Fire Weather index System were combined to assess possible changes in forest fire hazard in the Rocky Mountains. A wind model was developed to estimate daily wind speed variation with elevation. It was found that under most climate scenarios, fire hazard is predicted to increase. If future temperatures are warm, as expected, it could offset future precipitation increases, resulting in greater severity of fire weather and an in increase the number of days per year with high fire hazard.<br>xiii, 130 leaves ; 29 cm
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Hadlow, Ann Marie. "Changes in fire season precipitation in Idaho and Montana from 1982-2006." Diss., [Missoula, Mont.] : The University of Montana, 2009. http://etd.lib.umt.edu/theses/available/etd-05292009-105116/.
Full textAbstract:
Thesis (M.S.) -- University of Montana, 2009.<br>Title from author supplied metadata. Description based on contents viewed on October 14, 2009. Author supplied keywords: Fire, precipitation, season ending event, Remote Automated Weather Stations, North American Regional Reanalysis, Northern Rockies, climate change. Includes bibliographical references.
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Finlay, Christine School of Sociology & Anthropology UNSW. "Smokescreen : black/white/male/female bravery and southeast Australian bushfires." Awarded by:University of New South Wales. School of Sociology and Anthropology, 2005. http://handle.unsw.edu.au/1959.4/23006.
Full textAbstract:
Black/white/male/female struggles over knowledge correctness and who is brave are examined inductively in the field of bushfires. The paradoxes of a white male icon are linked to contradictions in gender theories in disaster. In mainstream literature, assumptions of innate white male superiority in bravery justify white women???s diminution and white male domination. In feminist theory, women???s diminution is the problem and their bravery for struggling against hegemony applauded. Philosophies of bravery are explored in 104 semistructured interviews and 12 months??? fieldwork as a volunteer bushfirefighter. There is great variety in the ways volunteers cope with bushfires. However, evidence of white male hegemony emerges when volunteers complain of state and territory indifference to preventing property and environmental damage and injury and death. Evidence is examined that Indigenous Australians once managed bushfires better than a sprawl of bureaucracy. Bushfire service claims that Aborigines knew nothing about hazard reductions are contradicted. This debate over bushfire management leads to the discovery of a third epistemology breaking with claims of white male iconic bravery and bureaucratic mastery. To generalise about the habitus of claims to knowledge and bravery, I analyse Newcastle Herald articles from 1881-1981. Three competing knowledge fields and their associated struggles are examined; Indigenous Australians and white womens??? emancipatory struggles confront data on bushfirefighting. Bushfires emerge as a serious problem, a bureaucratic power base and a white male icon from the 1920s.
38
Santos, Ana Isabel da Silva. "Análise do plano municipal de defesa da floresta contra incêndios do concelho de Monchique. Relatório Integrador da Atividade Profissional." Master's thesis, ISA/UTL, 2013. http://hdl.handle.net/10400.5/5638.
Full textAbstract:
Relatório Integrador da Atividade Profissional - Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia<br>The Municipal Plan to Protect Forests from Fires (MPPFF) emerged from the National Defense System of the Forest against Fire defined firstly by the Decree-Law nr. 156/2004, of June 30th, repealed by the Decree-Law nr. 124/2006, of June 28th, that was then altered by the Decree-Law nr. 17/2009, of January 14th.
The MPPFF Monchique defines the necessary measures for the forest defense against fires and includes integrated forecasting and planning of interventions by different entities before the occurrence of fires, within the jurisdiction of the Municipal Commission of the Defense of the Forest against Fire in Monchique. The MPPFF Monchique also aims intended to operate at local and municipal guidelines established in the National Plan to Protect Forests from Fires and District Plan to Protect Forests from Fires, being equally elaborated in line with the Regional Forest Management Plan for the Algarve.
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Shutler, Dave. "Post-fire bird communities and vegetation complexity." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66273.
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Laprise, Nathalie. "Utilisation de l'imagerie numérique aéroportée (capteurs Daedalus et Meis) pour identifier différents niveaux de perturbations d'un feu de forêt /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1997. http://theses.uqac.ca.
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Trusty, Paul Evan. "Impact of severe fire on ectomycorrhizal fungi of whitebark pine seedlings." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/trusty/TrustyP0509.pdf.
Full textAbstract:
Whitebark pine (Pinus albicaulis) is a threatened keystone species in subalpine zones of Western North America critical to watersheds and maintenance of high elevation biodiversity. Pine nuts are an important food for wildlife including grizzly bears. Whitebark pine stands have experienced losses up to 90% due to white pine blister rust, mountain pine beetles and replacement due to fire suppression. Active management strategies include letting natural fires burn or applying prescribed fires to clear understory fir, stimulate seedling regeneration and provide openings for nutcrackers to plant seeds. However, post-fire plantings of rust-resistant seedlings have low survival rates. This study evaluated the impact of fire on the mycorrhizal fungi which are obligate mutualists with whitebark pine and to address management concerns. The 2001 Fridley fire burned a portion of a mature whitebark pine forest and a year later 20,000 seedlings were planted. After four years, natural and planted seedlings, on the burn and controls in the adjacent unburned forest were well colonized by mycorrhizal fungi (>90%) although a portion may be nursery E-strain. The severe burn reduced mycorrhizal diversity 27% on natural and planted seedlings and caused a significant shift in mycorrhizal species (determined by ITS sequencing, principal component analysis and multidimensional scaling). Seedlings in the burn (natural and planted) were dominated by Pseudotomentella nigra, Wilcoxina species and Amphinema byssoides while natural seedlings in unburned forest hosted mainly Cenococcum geophilum and Piloderma byssinum. Differences were minimal between planted and natural seedlings in the burn, but roots of planted pines retained the container shape. The functional significance of a species shift to seedling survival is not yet known. Seedlings in all treatments hosted suilloid fungi (Rhizopogon, Suillus) important in pine establishment. A greenhouse bioassay of burned and unburned soils using nursery seedlings did not reflect the full diversity found in the field study, but did reveal suilloid fungi indicating that bioassays can be used as a pre-planting assessment tool for this group. Despite high mycorrhization and availability of suilloids, seedling survival was low (22-42%) suggesting the timing/type of mycorrhization and/or other biotic/abiotic factors are a concern.
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Boulfroy, Emmanuelle. "Prédiction de la regénération forestière naturelle après feu dans la forêt boréale québécoise /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1996. http://theses.uqac.ca.
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Ashaari, Zulfa Hanan. "Aerosols, forest fires and El Niño : air pollution issues in Malaysia." Thesis, University of Sheffield, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604650.
Full textAbstract:
In Malaysia, human activities, particularly biomass burning, have released tiny anthropogenic aerosols into the atmosphere. These tiny particles are intricately linked to the changes in the climate system by altering radiation budget properties, carbon and hydrological cycle. Furthermore, recent studies show that there is urgent need to fill the knowledge gap in understanding the relationship between regional and local controls on aerosols variability, particularly in Malaysia. The understanding of aerosols patterns is essential for predicting future trend and assessing aerosols impact to the regional and global climate evolution. Previous studies show ground based measurements coupled with remote sensing datasets have proved valuable for studying spatial and temporal aerosol distribution. However, such studies have been lacking in Malaysia. Therefore, this study aims to integrate ground-based measurements and satellite observations data to better understand the aerosols patterns in this region. In addition, the spatial-temporal patterns of aerosols load have been investigated in combination with forest fires, ENSO and meteorological analysis in an attempt to understand the aerosol system across Malaysia. This study compares the ground-based measurements data with those of the satellites data to evaluate the reliability of ground-based data. Ground-based data was compared with those of the satellite data of MODIS and OMI covering the years 2005 -2008: and ground-based AERONET data covering the years 2007-2008. Preliminary results of this study show that, in general, monthly mean of MODIS AOD and OMI AI as well as their temporal variation are in good agreement with ground-based data in the south peninsular and western Borneo area, which suggests there might be strong absorbing aerosols occurring in this area. However. MODIS AOD is better in presenting what happens on the ground. The comparison of MODIS and AMI aerosol properties agree well, and indicate the presence of high aerosol loads during ENSO years. The relationship between . AERONET and ground-based data exhibit moderate relationship probably due to the limited data availability. Furthermore. using regression analysis, TOMS Al data was found good to be used as a surrogate data to reconstruct ground data for the period 1980-1992. The relationship between TOMS AI and ground-based data improved when the amount of particulate matter captured by ground instrument is high. Furthermore, this work evaluates spatial, seasonal and inter-annual variability of aerosol load across Malaysia and its relation to forest fires, ENSO events and meteorological factors. for the 1980-2008 periods using rotated principal components analysis. The finding indicates that the variability of ground-based data can be decomposed into three components, each characterising different spatial and temporal variations. The first component characterises the south peninsular subregion with the ground-based data showing strong seasonal cycle with maximum concentrations found during the SW monsoon and minimum concentrations during the NE monsoon. It is found that fires emission from Sumatra contribute largely to aerosol loads during the SW monsoon in this sub-region. In addition, the concentrations in this sub-region are recorded to increase by 20 per cent during ENSO years. The second component characterised the region of the north peninsular; showing bimodality cycle of aerosol variation. This area exhibits two maximum concentrations which occurred during the end of the wet season and during the SW season as well as two minimum which recorded during the inter-monsoon season. It was found that concentrations in this sub-region are not related to Malaysian and Indonesian fires at all. This suggests fires from Indo-China may contribute to this sub-region concentration peaks value. The impact of ENSO events to the concentration in this Sub-region appears clearer between the 1992-2008 period where the concentrations are recorded to increase up to 40 per cent. The third component features the region of western Borneo showing a peak concentration in August-September, which results from the shift of the Inter Tropical Convergence Zone (ITCZ) to the northern-most location. Peaks in August-September are strongly associated to the minimum rainfall amounts. In addition, extreme observations found within this time period are strongly affected by fires emissions from Borneo. It was found that not all ENSO events have significant relationship with aerosol concentration in this sub-region. In general, this study concludes trends in anthropogenic aero sol in Malaysia during 1980-2008 are largely associated with forest tires and ENSO events and are also found to be strongly associated with rainfall cycle and ITCZ fluctuation.
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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.
Full textAbstract:
Thesis (MSc)--Stellenbosch University, 2015.<br>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.<br>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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Kamau, Peter Ngugi. "ANTHROPOGENIC FIRES, FOREST RESOURCES, AND LOCAL LIVELIHOODS AT CHYULU HILLS, KENYA." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1374078802.
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Hurtubise, Paula. "The distribution of lightning-caused forest fires in Quebec: 1978-1992." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/10333.
Full textAbstract:
This study is more in the nature of "exploratory" than "confirmatory" in its exploration of the temporal and spatial patterns of lightning-caused forest fires in Quebec, for the fifteen year period 1978 to 1992. Economic returns garnered from forest products, as well as species and habitat loss, make lightning-caused forest fires an important area for investigation. Natural forest fires are affected by many factors. For the purposes of this study two classes of variables are used in the investigation of the location and timing of lightning forest fires; these are species and weather data. The species data is gathered at the zone forest level and forest age is used at a mature or young level. Weather variables are limited to temperature, precipitation and thunderstorms. These are selected as a result of agreement in related literature that they are valid variables to work with. Lightning-caused fires are mapped at various temporal scales and these are compared with the species and weather data. The study reveals a dichotomous relationship, where fuel characteristics, or forest species, determine the location of fires (or spatial component), and weather dominates the temporal component. Finally, an attempt was made to make generalisations based on the findings so as to identify issues for further research. Understanding the mechanisms which drive the occurrence and distribution of lightning-caused forest fires, is one of the first steps in creating lightning-caused forest fire models.
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Small, Erin D. "Fire Ecology in the Acadian Spruce-Fir Region and Vegetation Dynamics Following the Baxter Park Fire of 1977." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/SmallED2004.pdf.
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Meyer, Natalie Jo. "Soil and plant response to slash pile burning in a ponderosa pine forest." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2008/meyer/MeyerN1208.pdf.
Full textAbstract:
Slash pile burning is the most common method of forest residue disposal following ponderosa pine restoration harvests, which are intended to reduce the risk of catastrophic fire and restore the historical structure and function of forests in western Montana. The impact of high-intensity, long-duration fire (pile burning) on soil processes and plant community dynamics is not well understood. The objectives of this study were: (1) to characterize the influence of slash pile burning on soil nutrient availability, soil microbial activity, and arbuscular mycorrhizal (AM) infection; (2) to compare seeding and soil amendment effects on burn scars. In May 2006, slash piles were burned in a ponderosa pine stand near Florence, Montana and 45 scars were sampled. Soil samples were collected from three locations in each slash pile to a depth of 10 cm and characterized for available soil NH4 +-N, NO3 - -N, potentially mineralizable nitrogen (PMN), and total C and N, water-soluble PO4 3- -P, microbial biomass, and mycorrhizal inoculum potential (MIP). In the burned center, soil NH4 +-N was greatest one month post-burn and remained elevated one year later. There was no observable increase in NO3 - -N until one year post-burn. Soluble PO4 3- -P was not impacted by burning. Microbial biomass was reduced by burning and did not recover one year later. Pile burning greatly reduced MIP. In October 2006, fire scars were either seeded with native graminoids or left non-seeded, divided into subplots, and assigned to one of five treatments: control, addition of local organic matter, scarification, scarification and organic matter addition, or scarification and commercial compost addition. Soils were monitored for the previously measured soil parameters and resin-sorbed inorganic N. Scarification with organic matter amendment and scarification with compost amendment both ameliorated soil properties. Seeding most effectively increased plant cover and suppressed non-native invasive species, while scarification or scarification with organic matter amendment further improved early plant establishment. Collectively, these data help characterize the impacts of slash pile burning as a management technique in ponderosa pine forests and illustrate potential treatments for restoring burn pile scars.
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Chau, Kam-chiu Lawrence, and 周錦超. "The ecology of fire in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B3123348X.
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Iniguez, Jose M. "Landscape Fire History and Age Structure Patterns in the Sky Islands of Southeastern Aizona." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/196138.
Full textAbstract:
At regional scales climate patterns (e.g., interannual wet-dry cycles) result in high spatial fire synchrony among Southwest forests. However, in the "Sky Island" forests of southeastern Arizona spatial and temporal patterns of fire history and tree age structure at landscape levels (i.e., within mountain ranges) are relatively unknown and therefore the focus of this study. In the Santa Catalina Mountains we reconstructed the fire history on a 2,900-hectare study area with two distinct landscapes, Butterfly Peak (BP) and Rose Canyon (RC) using 2-hectare "points" (i.e., collection areas). The RC landscape was dominated by shallow south-facing aspects and BP was dominated by steep north-facing aspects. Within each landscape, point mean fire intervals (PMFIs) were not significantly different between aspect classes. However, pooled PMFIs were significantly shorter in RC compared to BP. These results show that the fire history at any given point (i.e., 2 hectares or less) was primarily controlled by the broad-scale topography of the encompassing landscape, rather than by the fine-scale topography at that point.Using similar methods we also reconstructed the fire history on Rincon Peak, which is a small isolated mountain range with very step topography. The fire history of the 310-hectare forest area was a mixture of frequent low severity surface fires (from AD 1648 to 1763) and infrequent mixed-severity fires (from AD 1763 to 1867). This mixed-fire regime was probably due to a combination of climatic variability, the small area and rugged topography of this mountain range, and complex fuel arrangements. The distinct fire histories from these two study areas provided natural age structure experiments that indicated tree age cohorts (i.e., higher than expected tree establishment pulses) occurred during periods of reduced fire frequencies. In some instances these periods were likely caused by climatic variability (e.g., a wet and/or cool early 1800s) creating synchronous age cohorts across the region. At other times, extended fire intervals were a function of local topography (e.g., 1763-1819 in the northern half of Rincon Peak). Overall, these studies demonstrated that landscape and climatic variations combine to produce complex spatial and temporal variations in fire history and tree age structures.