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.

Published Article / The central regions of South Africa experienced an abnormally high precipitation during the first quarter of 2009, thus resulting in an unusually high probability of veld fires due to the excessive amounts of fuel / grass available. In South Africa the process of land redistribution was recently drastically accelerated. This implies that many newly settled black farmers are fanning but still need to be trained in various aspects of farm management. Unfortunately, in most cases this training did not include environmental management, which among others, implies managing and preparing for veld fires. The Department of Water Affairs and Forestry also does not have sufficient funding to cover all these aspects and a regional collaborative plan must therefore be developed. In addition to this, in an attempt to alleviate poverty, many other previously disadvantaged people in South Africa must be assisted in establishing small business enterprises. This paper will highlight a process to be followed to train and coordinate all farmers and simultaneously establish business opportunities that will remove some of the fuel (grasses and shrubs) in order to reduce the risk and intensity of winter and spring veld fires.

No description available.

Research into the psychological consequences of natural disasters in South Africa remains largely unexplored. This is surprising, given the devastating economical and psychological ramifications that result from major catastrophic events. No research has been done relating specifically to the experiences and coping strategies of fanners who have experienced a veld fire disaster in South Africa. Farmers constitute an important sub-group for study as they may be psychologically at risk to the effects of disasters. In the international research arena exploration of the long-term consequences of disasters is lacking. In considering the question of coping following a disaster, few studies have focused on the influence of temporal dynan1ics, which would seem to be crucial to the outcomes of coping strategies. This study aims to address these gaps in the literature by exploring the experiences and coping strategies of farmers who have experienced a veld fire disaster which occurred in the North West Province of South Africa on 23 August 2011. The total financial loss as a result of the fire amounted to R42 276 I 71. The fires were allegedly caused by damaged power lines, which produced sparks and ignited the nearby veld. This study used a qualitative design. This methodological approach was adopted for its ability to capture the complex and time-sensitive dynamics of coping strategies. This was combined with a case study approach, based on the experiences and coping strategies of eight farmers who had experienced a veld fire disaster within the boundaries of one geographical area. Semi-structured interviews were conducted with the farmers in their homes and were recorded, transcribed and thematically analysed. The results of the analysis showed that the farmers progressed through three time periods with distinct patterns of experience and corresponding coping strategies. The person environment relationship, as well as transitioning situational demands inherent in this relationship, were found to be crucial in determining the outcomes of the fanners• experiences and coping strategies. The results also suggest that successful coping is reliant on the individual’s ability to continually adapt their coping strategies in a context-appropriate manner. It is recommended that psychological debriefing should be avoided and that crisis intervention teams (CIT) should focus on the long-term consequences of the veld fire. Future coping research needs to take the temporal aspects of coping into account. / MA (Research Psychology), North-West University, Potchefstroom Campus, 2014

Important ecological processes happen over long periods of time and at the landscape scale. Effective conservation of biodiversity and management of natural resources and ecosystem services requires an understanding of these processes. Unfortunately, it is often impractical to conduct appropriate long-term, landscape-scale studies. Modelling offers an alternative approach. Complete ecosystems are too complex to model practically, but simulations of simplified systems provide useful insights of practical value. LandBaSE-P is an individual-based model for Puya hamata that provides information about impacts of fire on ecological processes in the páramo of the Reserva Ecológica El Ángel, Ecuador. Puya hamata is a flagship plant affected by fires and plays a key role in a number of ecological processes. This research found Puya hamata germinated much more frequently after fires, can form large aggregations of single recruitment cohorts, suffers very low mortality (with and without fires) once established, and lives up to 28 years. The spatial aggregation of Puya hamata plants reduced effective reproductive output, consistent with the theory that pollinator behaviour around large groups of Puya plants reduces cross-pollination, leading to inbreeding depression and poorer seed viability and germination. Puya hamata’s population structure can be an indicator of recent fire regime. LandBaSE-P simulations showed that population size is not affected by rare, long-distance seed dispersal. However, in the simulations of páramo grasslands, Puya relative germination is maintained in high numbers by burning. Puya hamata has an important role in ecology and biodiversity. The model LandBaSE-P is a complementary tool for conservation and sustainable land management. This thesis shows how fieldwork combined with laboratory studies and modelling, can provide a good understanding of complex dynamics of real-world populations, and generate ideas for management and future research.

This study was conducted in the Afram Headwaters, Tain Tributaries Block II and Worobong South Forest Reserves. Satellite record of fire incidence for the country over 11 years (1997 to 2007) was modelled via binary logistic regression analysis, and correlations between fire incidence and the correlates of fire used to explain the observed trends. Fire incidence was found to be correlated with multiple variables which probably covary. Rainfall, vegetation type and geology showed the strongest correlations with fire incidence. Recurrent fire has impacted negatively on forest structure, ground cover biomass and species composition in two forest reserves, but more marked in the wetter Worobong South Forest Reserve than the drier Tain II Forest Reserve. Basal area has reduced from 40 m²ha^-1 in least-degraded to <1 m²ha^-1 in heavily-degraded stand in Worobong South Forest Reserve, along with tree density, whereas canopy openness has increased from 6% in least-degraded to 83% in heavily-degraded forest. In Tain II Forest Reserve, however, the heavily-degraded forest has lost close to 50% of its maximum value in terms of basal area, tree density and canopy cover, all in approximately 20 years. Early-burning, with maximum seedling height growth rates of 130 cm yr^-1 and 40 cm yr^-1 for Worobong South and Tain II Forest Reserves respectively, might help control the fires, and restore forest canopy in about 10 to 20 years if regularly maintained, but must be accompanied by green firebreaks. Complete protection from fire (during convalescence), on the other hand, would take between five and 15 years to restore forest canopy, but at huge resource cost. Implications for sustainable forest management are discussed.

The Lesotho highlands are unique in many ways yet are at risk from severe degradation, primarily as a result of grazing and burning. This study aimed to determine whether recent (last 10-15 years) burning and grazing practices in the Sani region of eastern Lesotho are sustainable for the long-term survival of tussock grasses in the alpine belt. It was hypothesized that the alpine tussock grasses of Lesotho are being burnt and grazed at a rate that does not enable them to adequately recover between burns. A GIS based burn frequency and extent map was produced and indicated many small patchy burns (<100m2) were occurring within the Lesotho border, yet large scale burning (>10 000m2) occasionally breached the escarpment edge. Selected sites were monitored to determine the rate of growth and recovery of Merxmuellera drakensbergensis tussocks for a three year period (January 2009- December 2011). Increases were observed in basal circumference, living basal area and standing biomass yet the average height decreased across all sites and was attributed to grazing. A burn frequency of 4 burns per decade was found to be the optimum for retaining the greatest biomass, while a lack of burning for more than 9 years was suggested to result in a decrease in biomass. The leaves observed at a third of the diameter required the least average time of 6.3 years to recover to pre-burn heights as they are sheltered from environmental impacts and grazing. The middle tillers generally required the most time to recover to pre-burn heights (7.1 years) as the greatest competition for resources may be found in the centers as well as high possibilities of fire damage. The current burning activities are considered sustainable under the current levels of grazing occurring. The current levels of grazing are not advisable, especially as livestock numbers are increasing and grazing of the Sani region is becoming continuous throughout the year. A shortening of the average height of individuals within M. drakensbergensis communities is found, while increases were observed in invasive species cover. This research will add to the knowledge of environmental managers and hopefully actions may then be taken to better conserve the Lesotho highlands for future generations.

Due to continued outward expansion of industry and community development into the wildland-urban interface (WUI), the threat to life safety and property from wildland fires has become a significant problem. Such fire scenarios can be better understood through the use of computation fluid dynamics based fire-spread models. However, current physical fire models must be specifically adapted to handle the phenomena associated with WUI fires. Only then can they be reliably used as research and decision making tools to help mitigate the problem. In this research, the current standard in wildland fire modeling for representing the effect on wind flow from a porous vegetative medium is examined. The technique used employs basic correlations for object drag, and its validity with respect to real vegetation has yet to be examined in detail by the scientific community. The modeling of vegetation is studied within the framework of the existing Wildland-Urban Interface Fire Dynamics Simulator (WFDS), and the potential need for continued development is assessed. Comparisons are made to both experimental and numerical studies. Additionally, the validity of the model is considered at both the scale of an individual tree, as well as that of a whole forest canopy. Results show that as a first approximation the model is able to perform well in the latter case. At the scale of an individual tree, however, the behavior is governed by theoretical constants. The assumption of cylindrical vegetation elements performs slightly better than the commonly used spherical case, but neither adequately captures experimental tendencies. Accurate flow representation for single trees is crucial to modeling the key driving factors of fire behavior (such as combustion and heat transfer) in small scale WUI scenarios. Ultimately, this study illustrates the need for well-designed experiments, specifically to generate empirical constants which will improve the behavior of the simplified theory.

"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. "

Thesis. 1976. M.S.--Massachusetts Institute of Technology. Dept. of Ocean Engineering. / Microfiche copy available in Archives and Engineering. / Includes bibliographical references. / by George Economou. / M.S.