@article {bnh-8361, title = {Determining threshold conditions for extreme fire behaviour - final project report}, year = {2022}, month = {09/2022}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

In the last decade, there have been extreme wildfire events around the world resulting in substantial social, economic and environmental impacts. They threaten many lives and cost billions of dollars in damage. Climate change is making the fire seasons around the world even worse by extending the number of dry and hot days [1-4]. A longer fire season is expected to result in more frequent and severe fires [5, 6]. Australia{\textquoteright}s bushfire season 2019/20 (Black Summer fires hereafter) appears to have supported these conclusions in terms of the ecological consequences and impacts on human populations [7].

In most cases, these consequences are the result of dynamic fire behaviours (DFBs) [8-11]. The DFBs are localised dynamic events that occur within fires, whereby physical feedbacks greatly enhance fire intensities and rates of spread. Understanding and having the ability to predict DFBs in wildfire events is essential to ensure the safety of communities living in or near the Wildland-Urban Interface.

In this regard, the project {\textquoteleft}Determining threshold conditions for extreme fire behaviour{\textquoteright} was focused on the understanding and analysis of dynamic fire effects; their influence on fire behaviour and structures; and the potential of including these effects in fire behaviour models and new building standards.

}, issn = {735}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @inbook {bnh-8357, title = {Wildland fire}, booktitle = {Handbook of Fire and the Environment }, volume = {The Society of Fire Protection Engineers Series}, year = {2022}, publisher = {Springer}, organization = {Springer}, chapter = {Wildland Fire}, address = {Cham}, abstract = {

Wildfires, and their associated management activities, can have complex social, economic, and environmental impacts. This chapter highlights some of the key impacts of wildfires in six sections. The first section about community focuses on relationships between recent destructive wildfires around the globe and losses to life and property. It also presents the main mechanisms of house loss in the Wildland-Urban Interface. Following that, a section about biodiversity impacts describes the major effects of wildfires and associated fire regimes on plants and animals, underlining both negative and positive effects. Then, the focus shifts to soil and water with a section that highlights how wildfires can have serious implications for downstream water quality and yield, posing a threat to water security for the people and aquatic wildlife. This is followed by a section about air quality, which describes the effect of wildfires on visibility, human health and their contribution to climate change. The next section highlights the role of dynamic fire behaviours that lead to the most severe impacts, describing the fire behaviours themselves and their frequency of occurrence. The chapter closes with a case study describing the extreme impacts of the 2019/2020 fire season in south-eastern Australia on people and the environment.

}, isbn = {978-3-030-94356-1}, doi = {https://doi.org/10.1007/978-3-030-94356-1_7}, url = {https://link.springer.com/chapter/10.1007/978-3-030-94356-1_7}, author = {Alex Filkov and Jane Cawson and Matthew Swan and Trent Penman} } @article {bnh-8192, title = {Risk mitigation from prescribed burning in Kangaroo Island and Mount Lofty Ranges - Black Summer final report}, number = {690}, year = {2021}, month = {08/2021}, institution = {Bushfire and Natural Hazards CRC}, address = {MELBOURNE}, abstract = {

According to the Independent Review into South Australia{\textquoteright}s 2019-20 Bushfire Season, conditions were the worst on record with fires resulting in the loss of three human lives, 196 homes, 660 vehicles, 68,000 livestock, $200m of agricultural production. Around 280,000 ha were burnt by the fires, including total or partial burning of several National Parks.

The Bushfire and Natural Hazards CRC commissioned this project as part of a larger set of Black Summer fires research projects aimed at understanding the record-breaking fire season. This project focuses on answering questions about the effectiveness of prescribed burning, also known as hazard reduction burning, in mitigating risk in two areas affected by fires during the season: The Mount Lofty Ranges east of Adelaide, and Kangaroo Island.

The key questions were:

  1. How does risk respond to treatment in Kangaroo Island, an area with little formal quantification of prescribed burning benefits and costs?
  2. What was the risk in the leadup to the 2019-20 fire season in the Mt Lofty Ranges, and how will risk change in the next five years as a result of the implied fuel reduction from the fires, as well as alternative prescribed burning strategies?

These questions were answered using a well developed methodology combining large scale fire behaviour simulations and Bayesian risk quantification. Similar analyses have been carried out for a range of case study landscapes in southern Australia as part of the Hectares to tailor-made solutions CRC project, with results available online via the end-user tool the Prescribed Burning Atlas, and also the NSW Bushfire Risk Management Research Hub{\textquoteright}s projects for the NSW Bushfire Inquiry.

We found a clear relationship between the rate of prescribed burning and area subsequently burnt by wildfire in the Kangaroo Island case study. This translated into reductions in loss of life and property as well. Risk mitigation was more sensitive to edge treatment than landscape treatment, although both reduced risk. Conversely, increasing treatment (particularly at the edge) resulted in higher areas of the landscape exposed to vegetation being burnt below its minimum tolerable fire interval.

In the Mt Lofty Ranges, we found complex patterns of risk are likely in the aftermath of the 2019-20 fires. In the absence of further wildfire events, risk of area burnt is likely to rise substantially by 2025, regardless of prescribed burning rates, with a similar result for vegetation exposed to too frequent fire. However, risk sto life, property and infrastructure are projected to remain similar to current levels.

Our work contributes to the evidence base for prescribed burning planning in South Australia, with future work potentially examining new management values (e.g. smoke health costs, new biodiversity measures) and exploring empirical relationships between prescribed burning and fire-affected area in 2019-20.

}, keywords = {black summer, kangaroo island, mitigation, Mount Lofty Ranges, Prescribed burning, risk}, issn = {690}, author = {Hamish Clarke and Brett Cirulis and Owen Price and Ross Bradstock and Matthias M. Boer and Anthony Rawlins and Trent Penman} } @article {bnh-7499, title = {Determining threshold conditions for extreme fire behaviour - annual report 2019-2020}, number = {626}, year = {2020}, month = {11/2020}, institution = {Bushfire and Natural Hazards CRC}, address = {MELBOURNE}, abstract = {

At this phase the project was focused on development of a new method to test flammability of live vegetation in dynamic conditions and understanding influence of climatic changes on the 2019/20 bushfire season in New South Wales (NSW), Victoria, and South Australia (SA).

Understanding live vegetation fuel properties and how they behave when exposed to radiant heat and flame allows us to better predict fire behaviour in forested areas. This study aims to determine a more effective, replicable and accurate method of testing flammability in live vegetation by comparing the impact different radiant heating regimes have on the ignitibility of live vegetation samples. Current methodologies are limited in their ability to provide accurate quantification of flammability due to their reliance on static heat flux exposure, which does not accurately replicate how live plants experience radiative heat flux during a wildfire in their natural environment. Two heating regimes were tested for this study {\textendash} a static heat flux to reflect current methods and a dynamic (increasing) heat flux to more accurately replicate real conditions of an approaching fire front. Piloted-ignition and unpiloted-ignition were also tested for both of these heating regimes. A Variable Heat Flux (VHFlux) Apparatus was used to study flammability of Acacia floribunda, Cassinia arcuata, Pinus radiata and bark from Eucalyptus obliqua. Time to pyrolysis (production of volatile products), smouldering, flaming ignition, complete consumption and radiant exposure (the radiant energy received by a sample over a time of heating, He) were used as ignitability measures. It was observed that time and radiant exposure required to reach flaming ignition (and the other ignitibility metrics) was higher under a dynamic heating regime. It was also observed that the presence of a pilot igniter greatly increased the number of samples that reached flaming ignition, and decreased the time and He required to reach flaming ignition (and the other ignitibility metrics). These results suggest clear differences observed between heating regimes for time and Herequired for ignition and other ignitibility measures, which supports the validity of using dynamic heating regimes and the VHFlux apparatus as a standardised method. Adoption of this methodology is recommended to ensure more realistic data on flammability of individual plant species and plant communities, which will ultimately lead to better informed and more accurate wildfire behaviour modelling.

There is no doubt that the fire season of 2019/20 was extraordinary. A total of 18,983,588hectares were burned, 3113 houses and 33 lives lost in 15,344 bushfires in Black Summer fires. NSW had the highest number of fires, area burned, houses and lives lost for the last 20 years. Two mega-blazes occurred in NSW and burned more than in any fire season during the last 20 years. Victoria had the highest number of fires, area burned, and houses lost (except for the Black Saturday fires). SA had the highest number of houses lost in the last 20 years. Relationships between the burned area and number of fires, the houses and lives lost had positive trend for all states irrespective of the dataset. A negative relationship between the houses and lives lost for SA was the only exception. Multiple studies show that fire weather will become more severe in many regions around the world. Based on this and observed positive trends for all categories for NSW and Victoria, it is likely that the values will continue to increase in these states in the future. SA before 2019/20 was in a relatively good position showing negative trends for almost all categories. However, the 2019/20 fire season changed that for the worse. The magnitude of effect from increased fire weather may depend on how these conditions alter vegetation across Australia, however the indications shown in this analysis are concerning for fire managers.

Smoke from bushfires significantly impacted on people with cardiovascular and respiratory problems and increased mortality. It also had indirect impact on the economy by disrupting communities. The total impact of the 2019/20 bushfire season to the economy is estimated to be as much as A$40 billion. Due to the record burned area, at least 1 billion vertebrate animals were lost. It will take many years to restore the economy in impacted areas, and for animal and vegetation biodiversity to recover. Understanding of high-level trends of number of fires, area burned, houses and lives lost for the last two decades in south-eastern Australia will provide useful insights to fire managers for future strategies and policies.

}, keywords = {Behaviour, conditions, extreme fire, threshold}, issn = {626}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @article {bnh-7343, title = {Effect of weather forecast errors on fire growth model projections}, journal = {International Journal of Wildland Fire}, year = {2020}, month = {08/2020}, abstract = {

Fire management agencies use fire behaviour simulation tools to predict the potential spread of a fire in both risk planning and operationally during wildfires. These models are generally based on underlying empirical or quasi-empirical relations and rarely are uncertainties considered. Little attention has been given to the quality of the input data used during operational fire predictions. We examined the extent to which error in weather forecasts can affect fire simulation results. The study was conducted using data representing the State of Victoria in south-eastern Australia, including grassland and forest conditions. Two fire simulator software packages were used to compare fire growth under observed and forecast weather. We found that error in the weather forecast data significantly altered the predicted size and location of fires. Large errors in wind speed and temperature resulted in an overprediction of fire size, whereas large errors in wind direction resulted in an increased spatial error in the fire{\textquoteright}s location. As the fire weather intensified, fire predictions using forecast weather under predicted fire size, potentially resulting in greater risks to the community. These results highlight the importance of on-ground intelligence during wildfires and the use of ensembles to improve operational fire predictions.

}, keywords = {Bayesian Network, fire prediction, meteorological forecast, sensitivity, simulation}, doi = {https://doi.org/10.1071/WF19199}, url = {https://www.publish.csiro.au/wf/wf19199}, author = {Trent Penman and Dan Ababei and Jane Cawson and Brett Cirulis and Thomas Duff and Swedosh, W and James Hilton} } @article {bnh-7475, title = {Exploring the key drivers of forest flammability in wet eucalypt forests using expert-derived conceptual models}, journal = {Landscape Ecology}, volume = {35}, year = {2020}, month = {06/2020}, pages = {1775{\textendash}1798}, abstract = {

Context

Fire behaviour research has largely focused on dry ecosystems that burn frequently, with far less attention on wetter forests. Yet, the impacts of fire in wet forests can be high and therefore understanding the drivers of fire in these\ systems\ is vital.

Objectives

We sought to identify and rank by importance the factors plausibly driving flammability in wet eucalypt forests, and describe relationships between them. In doing so, we formulated a set of research priorities.

Methods

Conceptual models of forest flammability in wet eucalypt forests were elicited from 21 fire experts using a combination of elicitation techniques. Forest flammability was defined using fire occurrence and fireline intensity as measures of ignitability and heat release rate, respectively.

Results

There were shared and divergent opinions about the drivers of flammability in wet eucalypt forests. Widely agreed factors were drought, dead fine fuel moisture content, weather and topography. These factors all influence the availability of biomass to burn, albeit their effects and interactions on various dimensions of flammability are poorly understood. Differences between the models related to lesser understood factors (e.g. live and coarse fuel moisture, plant traits, heatwaves) and the links between factors.

Conclusions

By documenting alternative conceptual models, we made shared and divergent opinions explicit about flammability in wet forests. We identified four priority research areas: (1) quantifying drought and fuel moisture thresholds for fire occurrence and intensity, (2) modelling microclimate in dense vegetation and rugged terrain, (3) determining the attributes of live vegetation that influence forest flammability, (4) evaluating fire management strategies.

}, keywords = {Cognitive mapping, Conceptual models, Expert elicitation, Fire behaviour, fire intensity, flammability, Structured decision-making, Structured expert judgement, Wet forest, Wildfire}, doi = {https://doi.org/10.1007/s10980-020-01055-z}, url = {https://link.springer.com/article/10.1007/s10980-020-01055-z}, author = {Jane Cawson and Victoria Hemming and Ackland, A and Wendy R. Anderson and David Bowman and Ross Bradstock and Brown, T and Jamie Burton and Geoffrey J. Cary and Thomas Duff and Alex Filkov and Furlaud, James M. and Tim Gazzard and Kilinc, Musa and Petter Nyman and Ross Peacock and Mike Ryan and Jason J. Sharples and Gary J. Sheridan and Tolhurst, K.G. and Tim Wells and Phil Zylstra and Trent Penman} } @article {bnh-7389, title = {From hectares to tailor-made solutions for risk mitigation {\textendash} final project report}, number = {615}, year = {2020}, month = {09/2020}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

We are pleased to present the 2020 Final Report for the Bushfire and Natural Hazards CRC project, {\textquotedblleft}From hectares to tailor-made solutions for risk mitigation: systems to deliver effective prescribed burning across Australian ecosystems{\textquotedblright}.

Prescribed burning is a central feature of contemporary fire management, not just in Australia but in fire-prone countries around the world. Yet we lack a firm quantitative basis for understanding and comparing its effectiveness at mitigating risk across different regions. This project aims to address these gaps and provide critical support to agency decision makers across southern Australia by undertaking a systematic investigation of the drivers of prescribed burning effectiveness across the region. This project will thus support fire managers in transitioning from hectare targets to a set of tailor-made, risk-based approaches.

The project is divided into two phases: fire behaviour accounting and risk accounting. At the heart of the project is predictive modelling of the effect of prescribed burning on subsequent bushfire (wildfire) behaviour. In this project we combine ignition likelihood modelling, fuel type and arrangement from fire management agencies, weather representing all possible local fire weather conditions from Bureau of Meteorology and fire history including wildfire and variable combinations of edge and landscape treatments, applied to agency or model-derived burn blocks. From thousands of simulations, key outputs such as fire size and intensity are used estimate impacts on key management values: house loss, life loss, length of road damaged, length of powerline damaged and area burnt below minimum tolerable fire interval. We use Bayesian decision networks to estimate risk mitigation, including cost, available through different treatments. Local trajectories of cost for given treatment rates and locations can then be tracked and compared between regions, allowing identification of the most cost-effective prescribed burning strategies, either overall or for a given management value.

The key finding of the project is that the effectiveness of prescribed burning at mitigating area burnt by bushfire and other key values varies considerably across landscapes and values. That is, there is no one-size-fits-all solution to prescribed burning. This has major implications for fire managers, suggesting that tailored prescribed burning solutions are possible, based on the unique risk mitigation profile for any given suite of management values in that region. Further details are included in this report and journal articles listed herein.

While the project now draws to a close, its findings live on in the Prescribed Burning Atlas, a dedicated website for fire managers, researchers and anyone else interested in using our project to support their planning, decision making and communication. The Prescribed Burning Atlas will provide a geographically-based summary of risk for decision makers in an accessible, user friendly format. Our project is unique in placing the design and delivery of this utilisation output at its heart. Active involvement of end-users throughout 2020 and beyond will be crucial in ensuring uptake and translation into outcomes for end-users and the communities they serve. From a research perspective, key outstanding questions include quantification of risk mitigation for new values (smoke effects on human health, biodiversity measures, cultural burning) and expansion of the approach to represent the full richness of planned and unplanned landscape fire over time.

}, keywords = {ecosystems, hectares, mitigation, Prescribed burning, risk, systems, tailor-made solutions}, issn = {615}, author = {Hamish Clarke and Brett Cirulis and Trent Penman and Owen Price and Matthias M. Boer and Ross Bradstock} } @article {bnh-7036, title = {Impact of Australia{\textquoteright}s catastrophic 2019/20 bushfire season on communities and environment. Retrospective analysis and current trends}, journal = {Journal of Safety Science and Resilience}, year = {2020}, month = {07/2020}, abstract = {

2019/20 Australia{\textquoteright}s bushfire season (Black Summer fires) occurred during a period of record breaking temperatures and extremely low rainfall. To understand the impact of these climatic values we conducted a preliminary analysis of the 2019/20 bushfire season and compared it with the fire seasons between March 2000 and March 2020 in the states of New South Wales (NSW), Victoria, and South Australia (SA). Forest and fire management in Australia were asked to provide data on the number of fires, burned area, life and house loss, as well as weather conditions. By March 2020 Black Summer fires burnt almost 19 million hectares, destroyed over 3,000 houses, and killed 33 people. Data showed that they were unprecedented in terms of impact on all areas. A number of mega-fires occurred in NSW resulting in more burned area than in any fire season during the last 20 years. One of them was the largest recorded forest fire in Australian history. Victoria had a season with the highest number of fires, area burned, and second highest numbers of houses lost for the same period. SA had the highest number of houses lost in the last 20 years. Black Summer fires confirmed existing trends of impact categories during the last two decades for NSW and Victoria. It showed that the smoke from the bushfires may be a significant concern in the future for the global community, as it travels to other countries and continents. Based on preliminary data, it will take many years to restore the economy and infrastructure in impacted areas, and to recover animal and vegetation biodiversity.

}, keywords = {2019/20 season, bushfires, Impact, retrospective analysis}, doi = {https://doi.org/10.1016/j.jnlssr.2020.06.009}, url = {https://www.sciencedirect.com/science/article/pii/S2666449620300098}, author = {Alex Filkov and Tuan Ngo and Stuart Matthews and Simeon Telfer and Trent Penman} } @article {bnh-7708, title = {Leaf traits predict global patterns in the structure and flammability of forest litter beds}, journal = {Journal of Ecology}, year = {2020}, month = {12/2020}, abstract = {
  1. Fallen plant material such as leaves, needles and branches form litter beds which strongly influence fire ignition and spread. Traits of the dominant species influence litter flammability directly by determining how individual leaves burn and indirectly through the structure of the litter bed. However, we are yet to determine the relative importance of these different drivers across a range of plant species from different biomes.
  2. We undertook a meta-analysis, combining leaf trait, litter structure and flammability data for 106 species from North America, South America, Europe, Asia and Australia. The dataset encompassed broad-leaved and coniferous species from seven different experimental studies. Relationships between leaf traits, litter structure and key flammability metrics{\textemdash}sustainability, combustibility and consumability{\textemdash}were analysed using bivariate and piecewise structural equation modelling (SEM).
  3. Traits which characterise the three-dimensional nature of the leaf and how much space a leaf occupies showed much stronger associations to litter structure and flammability than other morphological traits. Leaf curl, surface area to volume ratio (SAV) and SLA predominately influence litter flammability indirectly via litter structure with SLA being the only leaf trait which had a negative direct effect on flame duration. Packing ratio and bulk density were influenced by different combinations of leaf traits and, in turn, they aligned with different flammability metrics. Bulk density predicted flame spread rate and flame duration whereas packing ratio predicted consumption.
  4. Synthesis. We identified key leaf and litter traits which influence different components of litter bed flammability. Importantly, we show that the effects of these leaf and litter traits are consistent across a wide range of taxa and biomes. Our study represents a significant step towards developing trait-based models for predicting surface wildfire behaviour. Such models will more flexibly accommodate future shifts in the composition of plant species triggered by altered fire regimes and climate change.
}, keywords = {Fire behaviour, flammability, leaf traits, litter properties, meta-analysis, surface fuel}, doi = {https://doi.org/10.1111/1365-2745.13561}, url = {https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2745.13561}, author = {Jamie Burton and Jane Cawson and Alex Filkov and Trent Penman} } @article {bnh-6854, title = {Cost effectiveness of fire management strategies in southern Australia}, journal = {International Journal of Wildland Fire}, volume = {29}, year = {2019}, month = {06/2019}, pages = {427-439}, abstract = {

Fire-management agencies invest significant resources to reduce the impacts of future fires. There has been increasing public scrutiny over how agencies allocate fire-management budgets and, in response, agencies are looking to use quantitative risk-based approaches to make decisions about expenditure in a more transparent manner. Advances in fire-simulation software and computing capacity of fire-agency staff have meant that fire simulators have been increasingly used for quantitative fire-risk analysis. Here we analyse the cost trade-offs of future fire management in the Australian Capital Territory (ACT) and surrounding areas by combining fire simulation with Bayesian Decision Networks. We compare potential future-management approaches considering prescribed burning, suppression and fire exclusion. These data combined costs of treatment and impacts on assets to undertake a quantitative risk analysis. The proposed approach for fuel treatment in ACT and New South Wales (NSW) provided the greatest reduction in risk and the most cost-effective approach to managing fuels in this landscape. Past management decisions have reduced risk in the landscape and the legacy of these treatments will last for at least 3 years. However, an absence of burning will result in an increased risk from fire in this landscape.

}, keywords = {Bayesian Network, house loss, life loss, prescribed fire, risk}, doi = { https://doi.org/10.1071/WF18128}, url = {https://www.publish.csiro.au/WF/WF18128}, author = {Trent Penman and Brett Cirulis} } @article {bnh-5830, title = {Determining threshold conditions for extreme bushfire behaviour annual report 2018-2019}, number = {508}, year = {2019}, month = {09/2019}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

Crown fires in forest ecosystems can pose a major threat to life and property due to their high intensities and rapid rates of spread. However, research into the prediction of crown fire dynamics in the Eucalyptus forests of Australia is limited. Previous studies have focused on coarse temporal scales, utilised low resolution weather based predictors, and often disregard the spatial nature of crown fires. Our study aimed to use observations from large wildfires in eucalypt forests to develop an empirical model to predict the likelihood of crown fire events using environmental predictors at an hourly scale. Our study was conducted in south-eastern Australia using data from fifteen large wildfires that occurred between 2009 and 2015. Fire severity maps were created for each fire at a 30\ m resolution using Landsat imagery from which we calculated the proportion of 30 m pixels experiencing crown fire within a 150 x 150 m window (2.25 ha). Predictor variables were chosen to represent the four key environmental drivers of fire behaviour, namely fuel moisture (i.e. live and dead fuel), fuel load and structure (i.e. surface, elevated, and bark fuels, and tree height), fire weather (i.e. vapour-pressure deficit, wind speed, relative wind direction) and topography (i.e. slope and ruggedness). Random Forests were used to model the effect of environmental drivers on the proportion of crown fire. Fuel moisture content variables were the best predictors of probability of crown consumption. Topographic variables and fire weather had only an intermediate influence and fuel load and structure had the lowest influence. Crown fire runs largely occurred when thresholds in vapour-pressure deficit (\<4\ kPa) and dead fuel moisture content (\<7\%) were exceeded. Predictions from the model showed a high degree of agreement with the raw fire severity maps. The proposed models have the potential to provide guidance on the likelihood of crown fire during fire events.

}, keywords = {Bushfire, extreme bushfires, fire behaviour., weather conditions}, issn = {508}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @article {bnh-5424, title = {Determining Threshold Conditions for Extreme Fire Behaviour Annual Report 2017-2018}, number = {460}, year = {2019}, month = {03/2019}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

Extreme fires cause disproportionate impacts on the environment and the community. There are significant incentives to being able to predict their occurrence and behaviour. Most existing fire behaviour models have been developed based on data and observations of fires that were small to moderate in size. Consequently, they are not able to emulate the dynamic bushfire behaviour that can occur under extreme conditions.

The main aim of this project is to investigate the conditions and processes under which bushfire behaviour undergoes major transitions, including fire convection and plume dynamics, evaluating the consequences of eruptive fire behaviour (spotting events, convection driven wind damage, rapid fire spread) and determining the combination of conditions for such behaviours to occur (e.g. unstable atmosphere, fuel properties and weather conditions). To do this the project was separated into two phases. The first phase of the project was focused on data collection about extreme fires, analysis the frequency of occurrence of extreme fire phenomena and determination the potential of including them in fire behaviour models.

}, keywords = {extreme fire behaviour, fire behavour, fire management}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @article {bnh-5648, title = {Developing and testing models of the drivers of anthropogenic and lightning-caused wildfire ignitions in south-eastern Australia}, journal = {Journal of Environmental Management}, volume = {235}, year = {2019}, month = {01/2019}, chapter = {34-41}, abstract = {

Considerable investments are made in managing fire risk to human assets, including a growing use of fire behaviour simulation tools to allocate expenditure. Understanding fire risk requires estimation of the likelihood of ignition, spread of the fire and impact on assets. The ability to estimate and predict risk requires both the development of ignition likelihood models and the evaluation of these models in novel environments. We developed models for natural and anthropogenic ignitions in the south-eastern Australian state of Victoria incorporating variables relating to fire weather, terrain and the built environment. Fire weather conditions had a consistently positive effect on the likelihood of ignition, although they contributed much more to lightning (57\%) and power transmission (55\%) ignitions than the 7 other modelled causes (8{\textendash}32\%). The built environment played an important role in driving anthropogenic ignitions. Housing density was the most important variable in most models and proximity to roads had a consistently positive effect. In contrast, the best model for lightning ignitions included a positive relationship with primary productivity, as represented by annual rainfall. These patterns are broadly consistent with previous ignition modelling studies. The models developed for Victoria were tested in the neighbouring fire prone states of South Australia and Tasmania. The anthropogenic ignition model performed well in South Australia (AUC = 0.969) and Tasmania (AUC = 0.848), whereas the natural ignition model only performed well in South Australia (AUC = 0.972; Tasmania AUC = 0.612). Model performance may have been impaired by much lower lightning ignition rates in South Australia and Tasmania than in Victoria. This study shows that the spatial likelihood of ignition can be reliably predicted based on readily available meteorological and biophysical data. Furthermore, the strong performance of anthropogenic and natural ignition models in novel environments suggests there are some universal drivers of ignition likelihood across south-eastern Australia.

}, keywords = {Bushfire, ignition, Risk modelling, Wildfire}, doi = {https://doi.org/10.1016/j.jenvman.2019.01.055}, url = {https://www.sciencedirect.com/science/article/pii/S0301479719300568}, author = {Hamish Clarke and Rebecca Gibson and Brett Cirulis and Ross Bradstock and Trent Penman} } @article {bnh-6393, title = {Frequency of Dynamic Fire Behaviours in Australian Forest Environments}, journal = {Fire}, volume = {3}, year = {2019}, month = {12/2019}, abstract = {

Wildfires can result in significant social, environmental and economic losses. Fires in which dynamic fire behaviours (DFBs) occur contribute disproportionately to damage statistics. Little quantitative data on the frequency at which DFBs occur exists. To address this problem, we conducted a structured survey using staff from fire and land management agencies in Australia regarding their experiences with DFBs. Staff were asked which, if any, DFBs were observed within fires greater than 1000 ha from the period 2006{\textendash}2016 that they had experience with. They were also asked about the nature of evidence to support these observations. One hundred thirteen fires were identified. Eighty of them had between one and seven DFBs with 73\% (58 fires) having multiple types of DFBs. Most DFBs could commonly be identified through direct data, suggesting an empirical analysis of these phenomena should be possible. Spotting, crown fires and pyro-convective events were the most common DFBs (66\%); when combined with eruptive fires and conflagrations, these DFBs comprise 89\% of all cases with DFBs. Further research should be focused on these DFBs due to their high frequencies and the fact that quantitative data are likely to be available.

}, keywords = {anecdotal data, direct data, dynamic fire behaviours, indirect data, Wildfire}, doi = {https://doi.org/10.3390/fire3010001}, url = {https://www.mdpi.com/2571-6255/3/1/1}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @article {bnh-5697, title = {From hectares to tailor-made solutions for risk mitigation: annual project report 2018-19}, number = {487}, year = {2019}, month = {07/2019}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

We are pleased to present the 2018-2019 Annual Report for the Bushfire and Natural Hazards CRC project, {\textquotedblleft}From hectares to tailor-made solutions for risk mitigation: systems to deliver effective prescribed burning across Australian ecosystems{\textquotedblright}. The project aims to provide critical support to agency decision makers across southern Australia by undertaking a systematic investigation of the drivers of prescribed burning effectiveness across the region. This report describes the background, research approach and key milestones since the previous Annual Report in 2017-2018. The report focuses on the research outputs informing the development of the Prescribed Fire Atlas. The project has now delivered a rich, layered dataset capable of addressing nuanced questions about the quantitative risk reduction available through prescribed burning for multiple management values in varying landscapes. The project is now entering its final phase as we complete climate change and cost-effectiveness analyses and launch the Prescribed Burning Atlas in 2019/20. The Prescribed Burning Atlas will provide geographically based summary of risk for decision makers in an accessible, user friendly format. Our project is unique in placing the design and delivery of this utilisation output at the heart of the project. Active involvement of end users throughout 2020 and beyond will be crucial in ensuring uptake and translation into outcomes for end users and the communities they serve.

}, keywords = {cost-effective, ecosystems, fire management, Prescribed burning}, author = {Hamish Clarke and Owen Price and Matthias M. Boer and Brett Cirulis and Trent Penman and Ross Bradstock} } @conference {bnh-6396, title = {A new decision support tool for prescribed burning risk assessment}, booktitle = {Bushfire and Natural Hazards CRC Research Day AFAC19}, year = {2019}, month = {12/2019}, address = {Melbourne}, abstract = {

In most Australian jurisdictions, the use of prescribed fire is promoted on the basis of its efficacy in mitigation of risk. Despite this, formal attempts to evaluate effects on risk to people, property and environmental values across different jurisdictions are generally lacking. In particular, there is no basis for assessing the generality of attempts to predict risk in response to any particular strategy for use of prescribed fire (e.g. the 5per cent target recommended by the 2009 Victorian Bushfires Royal Commission). General principles therefore need to be developed about how to apply a risk-based approach across widely varying environments, human communities and combinations of key management values.

In this Bushfire and Natural Hazards Cooperative Research Centre project, researchers from the University of Wollongong, Western Sydney University and the University of Melbourne have come together with end users across southern Australia to design a project to systematically investigate how risk to any particular management value will respond to variations in the spatial location and rates of treatment. Project outputs are currently being moulded for utilisation by end users in a dedicated tool, the Prescribed Fire Atlas, which will guide the implementation of {\textquoteleft}tailor-made{\textquoteright} prescribed burning strategies to suit the biophysical, climatic and human context of all bioregions across southern Australia.

}, keywords = {decision support, Fire, perscibed burning, risk management}, url = {https://knowledge.aidr.org.au/resources/australian-journal-of-emergency-management-monograph-series/}, author = {Hamish Clarke and Brett Cirulis and Ross Bradstock and Matthias M. Boer and Trent Penman and Owen Price} } @article {bnh-5615, title = {Quantification of inter-regional differences in risk mitigation from prescribed burning across multiple management values}, journal = {International Journal of Wildland Fire}, year = {2019}, month = {06/2019}, abstract = {

Fire agencies are moving towards planning systems based on risk assessment; however, knowledge of the most effective way to quantify changes in risk to key values by application of prescribed fire is generally lacking. We present a quantification and inter-regional comparison of how risk to management values responds to variations in prescribed burning treatment rate. Fire simulations were run using the PHOENIX RapidFire fire behaviour simulator for two case study landscapes in interface zones in Tasmania and the Australian Capital Territory (ACT), Australia. A Bayesian network approach used these data to explore the influence of treatment and weather on risk from wildfire. Area burnt, length of powerline damaged and length of road damaged responded more strongly to treatment in the ACT than in Tasmania, whereas treatment mitigated house loss and life loss more strongly in Tasmania than the ACT. The effect of prescribed burning treatment rate on area burnt below minimum tolerable fire interval was similar in each case study landscape. Our study shows that the effectiveness of prescribed burning at mitigating area burnt by wildfire and other key values varies considerably across landscapes and values.

}, keywords = {Bushfire, Climate change, trends, Wildfire, wildland fire}, doi = {https://doi.org/10.1071/WF18135}, url = {http://www.publish.csiro.au/WF/WF18135}, author = {Brett Cirulis and Hamish Clarke and Matthias M. Boer and Trent Penman and Owen Price and Ross Bradstock} } @article {bnh-6856, title = {Quantification of inter-regional differences in risk mitigation from prescribed burning across multiple management values}, journal = {International Journal of Wildland Fire}, volume = {29}, year = {2019}, month = {09/2019}, pages = {414-426}, abstract = {

Fire agencies are moving towards planning systems based on risk assessment; however, knowledge of the most effective way to quantify changes in risk to key values by application of prescribed fire is generally lacking. We present a quantification and inter-regional comparison of how risk to management values responds to variations in prescribed burning treatment rate. Fire simulations were run using the PHOENIX RapidFire fire behaviour simulator for two case study landscapes in interface zones in Tasmania and the Australian Capital Territory (ACT), Australia. A Bayesian network approach used these data to explore the influence of treatment and weather on risk from wildfire. Area burnt, length of powerline damaged and length of road damaged responded more strongly to treatment in the ACT than in Tasmania, whereas treatment mitigated house loss and life loss more strongly in Tasmania than the ACT. The effect of prescribed burning treatment rate on area burnt below minimum tolerable fire interval was similar in each case study landscape. Our study shows that the effectiveness of prescribed burning at mitigating area burnt by wildfire and other key values varies considerably across landscapes and values.

}, keywords = {Bushfire, Climate change, trends, Wildfire, wildland fire}, doi = {https://doi.org/10.1071/WF18135}, url = {https://www.publish.csiro.au/WF/WF18135}, author = {Brett Cirulis and Hamish Clarke and Matthias M. Boer and Trent Penman and Owen Price and Ross Bradstock} } @conference {bnh-6549, title = {Quantifying dynamic fire behaviour phenomena using Unmanned Aerial Vehicle technology }, booktitle = {23rd International Congress on Modelling and Simulation}, year = {2019}, month = {12/2019}, address = {Canberra}, abstract = {

Catastrophic wildfires are often a result of dynamic fire behaviours. Although some of these behaviours have been described and investigated, others require further study. Fire coalescence and junction fires are particular cases of merging fire fronts and are common phenomena observed during bushfires. They are important as they can cause rapid escalation of fire behaviour and be dangerous for ground-based emergency personnel. There are a few studies devoted to investigation of merging fires in field conditions. There is a need for high temporal and spatial measurements of fire behaviour in field conditions in order to better understand this phenomenon and evaluate risks during bushfires and prescribed burning. The aim of this study was to test emerging technologies for better quantification of fire behaviour at field scales and evaluate their potential as an operational tool.

Several small and medium scale field experiments were conducted during April 2019 on farmland in Victoria, Australia. Harvested wheat fields were used as experimental plots, as they form relatively homogeneous fuel beds. Fuel height varied from 18 to 40 cm with fuel load and moisture content at 1.1 t/ha and 11.9 \% respectively. Wind speed varied in the range of 1.5-6.5 m/s. An Unmanned Aerial Vehicle (UAV) was used to capture high definition video imagery of fire propagation in synchronisation with sensor data from the on-board Global Positioning System (GPS) and Inertial Measurement Unit (IMU). These sensors enabled the platform/camera orientation and position in space to be aligned with the video footage of fire propagation and to be georeferenced in GIS software.

Twenty-one junction fires and five inward parallel fire fronts (parts of the fire lines approaching each other) were identified during the experiments. The rate of spread (ROS) of merging fire fronts was found to be at least two times higher than for the basic fire fronts (the rate of spread of a linear fire front in the same fuel bed in no-slope conditions) and for junction fires with acute angles (\< 14{\textdegree}) it increased 6 times and more. Inward parallel fire fronts spread much slower, varying between 0.05 and 0.25 m/s. Forty-six percent of junction fires had increase of the ROS at the final stage of the merging process in contrast to Thomas et al. (2017) and Viegas et al. (2012). Also, it was observed that the angle between two oblique fire fronts did not change significantly in time for the initial angles smaller than 34{\textdegree}. It can be assumed that the main fire front influences on the shape and ROS respectively of junction fires and laboratory experiments cannot fully replicate these conditions.

Although the initial experimental conditions were very different in relation to scale, fuel and wind conditions, similar ROS to that shown in numerical simulations by Thomas et al. (2017) were observed in our field experiments. Further investigation is required to explain the similarities as the relationship between fuel load, wind speed and scale is not known. The comparison of corrected values of dimensionless ROS for different angles between fire fronts with laboratory experiments of Viegas et al. (2012) showed reasonable quantitative agreement.

These experiments have shown that the method of using UAV{\textquoteright}s to capture georeferenced video footage can be used reliably to quantify fire behaviour phenomena for research, operation and management purposes.

Catastrophic wildfires are often a result of dynamic fire behaviours. Although some of these behaviours have been described and investigated, others require further study. Fire coalescence and junction fires are particular cases of merging fire fronts and are common phenomena observed during bushfires. They are important as they can cause rapid escalation of fire behaviour and be dangerous for ground-based emergency personnel. There are a few studies devoted to investigation of merging fires in field conditions. There is a need for high temporal and spatial measurements of fire behaviour in field conditions in order to better understand this phenomenon and evaluate risks during bushfires and prescribed burning. The aim of this study was to test emerging technologies for better quantification of fire behaviour at field scales and evaluate their potential as an operational tool.

Several small and medium scale field experiments were conducted during April 2019 on farmland in Victoria, Australia. Harvested wheat fields were used as experimental plots, as they form relatively homogeneous fuel beds. Fuel height varied from 18 to 40 cm with fuel load and moisture content at 1.1 t/ha and 11.9 \% respectively. Wind speed varied in the range of 1.5-6.5 m/s. An Unmanned Aerial Vehicle (UAV) was used to capture high definition video imagery of fire propagation in synchronisation with sensor data from the on-board Global Positioning System (GPS) and Inertial Measurement Unit (IMU). These sensors enabled the platform/camera orientation and position in space to be aligned with the video footage of fire propagation and to be georeferenced in GIS software.

Twenty-one junction fires and five inward parallel fire fronts (parts of the fire lines approaching each other) were identified during the experiments. The rate of spread (ROS) of merging fire fronts was found to be at least two times higher than for the basic fire fronts (the rate of spread of a linear fire front in the same fuel bed in no-slope conditions) and for junction fires with acute angles (\< 14{\textdegree}) it increased 6 times and more. Inward parallel fire fronts spread much slower, varying between 0.05 and 0.25 m/s. Forty-six percent of junction fires had increase of the ROS at the final stage of the merging process in contrast to Thomas et al. (2017) and Viegas et al. (2012). Also, it was observed that the angle between two oblique fire fronts did not change significantly in time for the initial angles smaller than 34{\textdegree}. It can be assumed that the main fire front influences on the shape and ROS respectively of junction fires and laboratory experiments cannot fully replicate these conditions.

Although the initial experimental conditions were very different in relation to scale, fuel and wind conditions, similar ROS to that shown in numerical simulations by Thomas et al. (2017) were observed in our field experiments. Further investigation is required to explain the similarities as the relationship between fuel load, wind speed and scale is not known. The comparison of corrected values of dimensionless ROS for different angles between fire fronts with laboratory experiments of Viegas et al. (2012) showed reasonable quantitative agreement.

These experiments have shown that the method of using UAV{\textquoteright}s to capture georeferenced video footage can be used reliably to quantify fire behaviour phenomena for research, operation and management purposes.

}, keywords = {fire front propagation, merging fire fronts, Remote measurements, UAS}, url = {https://www.researchgate.net/publication/338412609_Quantifying_dynamic_fire_behaviour_phenomena_using_Unmanned_Aerial_Vehicle_technology}, author = {Alex Filkov and Brett Cirulis and Trent Penman} } @article {bnh-4998, title = {Determining threshold conditions for extreme fire behaviour}, number = {417}, year = {2018}, month = {10/2018}, institution = {Bushfire and Natural Hazards CRC}, abstract = {

Flame spread is an important process in the propagation of bushfires. The likelihood of ignition and combustion rates of fuels are dependent on the type and nature of the heat flux. The majority of previous research has used static heat flux, whereby a consistent heating source is used to ignite samples in a laboratory setting. This is despite the highly dynamic heating regimes typically observed during structural and wildland fires.

}, keywords = {Fire, fire behaviour., fire modelling, fire severity, modelling}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @conference {bnh-4743, title = {Extreme fire behaviours: Surveying fire management staff to determine behaviour frequencies and importance}, booktitle = {AFAC18}, year = {2018}, month = {09/2018}, publisher = {Bushfire and Natural Hazards CRC}, organization = {Bushfire and Natural Hazards CRC}, address = {Perth}, abstract = {

An understanding how bushfires cause damage is important if they are to be effectively managed. Extreme fire behaviours (EFBs) are phenomena that occur within intense fires that have been shown to contribute greatly to their to impacts. However, there exists little understanding regarding how often particular EFBs occur, how these contribute to fire behaviour and what importance should be allocated to each in the development of models for decision support. To address this problem, we surveyed fire fighters from fire and land management agencies in Australia regarding their experiences with EFBs. All fires greater than 1000 ha in the period 2006-2016 were considered in the survey. Representatives were asked which, if any, EFBs they had observed and whether there was any documentation to support these observations. We found that EFBs are common in large fires. In more than 60 \% of case studies, each bushfire had two and more EFBs simultaneously (or one after another). Our survey indicated that Spotting, Crown fires, Pyro-convective events, Eruptive fires and Conflagrations are the most commonly observed EFBs, and so should be a priority for research. The relative commonness of direct evidence available for EFBs is indicative that there should be the potential for further study of these phenomena.\ 

}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @article {bnh-5035, title = {From hectares to tailor-made solutions for risk mitigation: annual project report 2017-18}, year = {2018}, month = {10/2018}, institution = {Bushfire and Natural Hazards CRC}, abstract = {

This report describes the background, research approach and key milestones since the 2016-2017 Annual Report. The report focuses on the analysis of fire spread simulations for two case study landscapes: the ACT and Tasmania. The analysis demonstrates that it is possible to investigate prescribed burning effectiveness at risk mitigation across a range of treatment levels, management values and landscapes, by placing them on a common baseline of risk.

}, issn = {421}, author = {Hamish Clarke and Owen Price and Matthias M. Boer and Brett Cirulis and Trent Penman and Ross Bradstock} } @article {bnh-4458, title = {Improving Fire Behaviour Data Obtained from Wildfires}, journal = {Forests}, volume = {9}, year = {2018}, month = {02/2018}, abstract = {

Organisations that manage wildfires are expected to deliver scientifically defensible decisions. However, the limited availability of high quality data restricts the rate at which research can advance. The nature of wildfires contributes to this: they are infrequent, complex events, occur with limited notice and are of relatively short duration. Some information is typically collected during wildfires, however, it is often of limited quantity and may not be of an appropriate standard for research. Here we argue for a minimum standard of data collection from every wildfire event to enhance the advancement of fire behaviour research and make research findings more internationally relevant. First, we analyse the information routinely collected during fire events across Australia. Secondly, we review research methodologies that may be able to supplement existing data collection. Based on the results of these surveys, we develop a recommended list of variables for routine collection during wildfires. In a research field typified by scarce data, improved data collection standards and methodologies will enhance information quality and allow the advancement in the development of quality science.

}, keywords = {data collection and management, Fire behaviour, research utilization, standard.}, doi = {10.3390/f9020081}, url = {http://www.mdpi.com/1999-4907/9/2/81}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @conference {bnh-4774, title = {A systematic exploration of the potential for bushfire risk mitigation with prescribed burning}, booktitle = {AFAC18}, year = {2018}, month = {09/2018}, publisher = {Bushfire and Natural Hazards CRC}, organization = {Bushfire and Natural Hazards CRC}, address = {Perth}, abstract = {

Fire regimes vary widely across Australian ecosystems as a function of climate, fuel, terrain and ignition variations. Fundamentally such variation will not only shape the way that prescribed burning can reduce risk to human and environmental assets but also the scope for effective treatment. While many agencies are moving toward planning systems based on risk assessment, knowledge of the best way to use prescribed fire to reduce risk to key values is generally lacking. The BNHCRC Project, {\textquotedblleft}From hectares to tailor-made solutions for prescribed burning{\textquotedblright}, combines simulation and empirical approaches to improve our understanding of how risk to any particular management value will respond to variations in the spatial location and rates of treatment. Here, we present the modelling framework and key results for two landscapes, Tasmania and the Australian Capital Territory. We run a large number of simulations using the PHOENIX RapidFire model, investigating the interaction between fuel treatment and location under various weather scenarios. Key outputs for risk assessment include area burnt, house loss, life loss, roads and powerlines damaged, environmental cost and economic cost. Across both case study landscapes, greater levels of prescribed burning tend to result in reduced wildfire impacts on all risks. However, there is considerable variation in the rate of reduction in risk, including the amount of treatment required to achieve key targets. Further, the particular combination of weather factors underpinning given fire weather conditions (e.g. temperature vs wind driven) can substantially impact the overall level of risk, as well as the response to prescribed burning.\ 

}, author = {Brett Cirulis and Hamish Clarke and Ross Bradstock and Matthias M. Boer and Trent Penman and Owen Price} } @article {bnh-4206, title = {Determining threshold conditions for extreme fire behaviour: annual project report 2016-17}, number = {319}, year = {2017}, month = {09/2017}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

Organisations that manage bushfires are expected to deliver scientifically defensible decisions. However, the limited availability of high quality data restricts the rate at which research can advance. The nature of bushfires contributes to this; they are infrequent, complex events, occur with limited notice and are of relatively short duration. Some information is typically collected during bushfires however it may not be of an appropriate standard for research. In the past year we have focused on the information that is typically collected during fires. First we reviewed the information routinely collected during fire events across Australia. Secondly, we reviewed research methodologies that may be able to supplement existing data collection. Based on the results of these surveys, we developed a recommended list of attributes for routine collection during bushfires. We also suggest standards of data collection from bushfire events to enhance the advancement of fire behaviour research and make research findings more internationally relevant. In a research field typified by scarce data, improved data collection standards and methodologies will enhance information quality and allow the advancement in the development of quality science (1). In addition to the fire data review, we investigated embers, including their production and how they burn (2,3).

}, issn = {319}, author = {Alex Filkov and Thomas Duff and Trent Penman} } @article {bnh-4203, title = {From hectares to tailor-made solutions for risk mitigation - systems to deliver effective prescribed burning across Australian ecosystems: annual project report 2016-17}, number = {310}, year = {2017}, month = {09/2017}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

We are pleased to present the 2016-2017 Annual Report for the Bushfire and Natural Hazards CRC project, From hectares to tailor-made solutions for risk mitigation: systems to deliver effective prescribed burning across Australian ecosystems. By undertaking a systematic investigation of the drivers of prescribed burning effectiveness across southern Australia, the project will provide critical support to agency decision makers across the region.

This report describes the project goals, methods and activities since the 2015-2016 Annual Report. The report focuses on initial results from a key project component: fire spread simulations in a range of case study landscapes throughout southern Australia. Results are presented in detail for case studies in East Central Victoria, Adelaide, the ACT and Hobart. This initial suite of simulations provides good evidence that there is substantial variation between case study landscapes in the response of key risks to different rates of prescribed burning. Further simulations in combination with other project methodologies will provide further evidence about this critical issue.

The report also details progress on data acquisition, empirical analyses and stakeholder engagement, which form the other key activities of the project to date. Finally, we are graetful to Naomi Stephens and Felipe Aires, our End User representatives from the NSW Office of Environment and Heritage, for providing an insight into the project{\textquoteright}s progress from a stakeholder perspective.

}, issn = {310}, author = {Hamish Clarke and Owen Price and Matthias M. Boer and Brett Cirulis and Trent Penman and Ross Bradstock} } @article {bnh-2922, title = {Determining threshold conditions for extreme fire behaviour: Annual project report 2015-2016}, number = {175}, year = {2016}, month = {08/2016}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

As extreme fires cause a disproportionate amount of impact to the environment and the community, there are significant incentives to being able to predict their occurrence and behaviour. Most existing fire behaviour models have been developed based on data and observations of fires that were small to moderate in size. Consequently, they are not able to emulate the dynamic bushfire behaviour that can occur under extreme conditions.

Indeed, current operational fire spread models assume that fires will burn at an approximately constant (quasi-steady) rate of spread under a specific set of environmental conditions (e.g. VESTA, McArthur Mk5, CSIRO models). While a number of advances have been made in understanding bushfire development under extreme conditions, these have not been quantified in a manner that is suitable for inclusion in a fire behaviour modelling framework.

The main aims of this project are to investigate the conditions and processes under which bushfire behaviour undergoes major transitions, including fire convection and plume dynamics, evaluating the consequences of eruptive fire behaviour (spotting events, convection driven wind damage, rapid fire spread) and determining the combination of conditions for such behaviours to occur (e.g. unstable atmosphere, fuel properties and weather conditions). To do this the collation and analysis of existing data on extreme fire behaviour will be done.

}, issn = {175}, author = {Thomas Duff and Trent Penman and Alex Filkov} } @article {bnh-3437, title = {Into the firing line: civilian ingress during the 2013 {\textquotedblleft}Red October{\textquotedblright} bushfires, Australia}, journal = {Natural Hazards}, volume = {80}, year = {2016}, month = {01/2016}, pages = {521-538}, chapter = {521}, abstract = {

A major issue for bushfire management arises when residents decide to leave a safe area and enter the fire zone to rescue or defend their property, pets, loved ones or other assets. Here, we use statistical and narrative analyses of data from an online survey and semi-structured interviews with residents affected by the 2013 {\textquotedblleft}Red October{\textquotedblright} bushfires in New South Wales, Australia. The survey results revealed that of the 58\ \% of respondents who were not at home at the time the threat became apparent, 65\ \% indicated that they attempted to get home prior to the arrival of the fire front. In doing so, many endangered themselves, their family, friends and emergency services personnel. This paper discusses the shortcomings of bushfire survival plans and official risk communication, which do not cater well for household units that are divided or unattended when a bushfire starts. Findings suggest that to enhance bushfire safety and preparedness, emergency managers should acknowledge and speak more directly to the specific constraints to action for particular social groups at the wildland{\textendash}urban interface, including families with school-age children, commuters and absentee landholders.

}, doi = {10.1007/s11069-015-1982-5}, url = {https://link.springer.com/article/10.1007/s11069-015-1982-5}, author = {Wilkinson, Carrie and Eriksen, Christine and Trent Penman} } @article {bnh-3410, title = {Resolving future fire management conflicts using multi-criteria decision making}, journal = {Conservation Biology}, volume = {30}, year = {2016}, month = {02/2016}, pages = {196-205}, chapter = {196}, abstract = {

Management strategies to reduce the risks to human life and property from wildfire commonly involve burning native vegetation. However, planned burning can conflict with other societal objectives such as human health and biodiversity conservation. These conflicts are likely to intensify as fire regimes change under future climates and as growing human populations encroach farther into fire-prone ecosystems. Decisions about managing fire risks are therefore complex and warrant more sophisticated approaches than are typically used. We applied a multicriteria decision making approach (MCDA) with the potential to improve fire management outcomes to the case of a highly populated, biodiverse, and flammable wildland{\textendash}urban interface. We considered the effects of 22 planned burning options on 8 objectives: house protection, maximizing water quality, minimizing carbon emissions and impacts on human health, and minimizing declines of 5 distinct species types. The MCDA identified a small number of management options (burning forest adjacent to houses) that performed well for most objectives, but not for one species type (arboreal mammal) or for water quality. Although MCDA made the conflict between objectives explicit, resolution of the problem depended on the weighting assigned to each objective. Additive weighting of criteria traded off the arboreal mammal and water quality objectives for other objectives. Multiplicative weighting identified scenarios that avoided poor outcomes for any objective, which is important for avoiding potentially irreversible biodiversity losses. To distinguish reliably among management options, future work should focus on reducing uncertainty in outcomes across a range of objectives. Considering management actions that have more predictable outcomes than landscape fuel management will be important. We found that, where data were adequate, an MCDA can support decision making in the complex and often conflicted area of fire management.

}, doi = {10.1111/cobi.12580}, url = {http://onlinelibrary.wiley.com/doi/10.1111/cobi.12580/abstract}, author = {Don A. Driscoll and Michael Bode and Ross Bradstock and David A. Keith and Trent Penman and Owen Price} } @article {bnh-3432, title = {Biogeographical variation in the potential effectiveness of prescribed fire in south-eastern Australia}, journal = {Journal of Biogeography}, volume = {42}, year = {2015}, month = {09/2015}, pages = {2234-2245}, chapter = {2234}, abstract = {

Aim

Prescribed fire is a common land management for reducing risks from unplanned fires. However, the universality of such effectiveness remains uncertain due to biogeographical variation in fuel types, climatic influences and fire regimes. Here, we explore biogeographical patterns in the effectiveness of prescribed fire by calculating leverage (the reduction in unplanned area burnt resulting from recent previous area burnt) across south-eastern Australia over a 25\ year period.

Location

The 30 bioregions of south-eastern Australia.

Methods

We quantified leverage in each bioregion from fire records from 1975{\textendash}2009, controlling for variation in annual weather. We also identified potential drivers of variation in leverage by relating the bioregional leverage values to measures of fuel type and growth, climate, and weather extremes.

Results

Leverage was inferred in four bioregions while in the other 26 bioregions no leverage was detected or prescribed fire had the opposite effect (fire-follows-fire). Leverage occurred in the forested eastern section of the study area, where rainfall, fuel load and fire activity is high and fire weather is mild. In all bioregions, weather was a stronger predictor than past-fire extent of area burnt in a particular year.

Main conclusions

Our analysis of leverage shows that the effectiveness of prescribed fire varies regionally in predictable ways, which means that fuel management strategies applied in one region are not necessarily applicable in another. In most bioregions prescribed burning is likely to have very little effect on subsequent extent of unplanned fire, and even in regions where leverage occurs, large areas of treatment are required to substantially reduce the area burned by unplanned fire.

}, doi = {10.1111/jbi.12579}, url = {http://onlinelibrary.wiley.com/doi/10.1111/jbi.12579/abstract}, author = {Owen Price and Trent Penman and Ross Bradstock and Matthias M. Boer and Hamish Clarke} } @article {bnh-2395, title = {Determining threshold conditions for extreme fire behaviour}, year = {2015}, author = {Thomas Duff and Trent Penman} } @article {bnh-2340, title = {Determining threshold conditions for extreme fire behaviour: Annual project report 2014-2015}, number = {133}, year = {2015}, month = {02/11/2015}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

Fire behavior models that predict the progression of bushfires are becoming increasingly important in management.\  Most existing models have been developed based on data and observations of fires burning under relatively mild conditions.\  If the models are to be relied upon for fires that occur under extreme weather conditions (where fires are fast moving and more intense), these conditions must also be considered in their design.

There is increasing evidence that there are particular fire phenomena that occur only in extreme fire conditions.\  These include fire tornados, atmospheric coupling, ember storms and vorticity driven lateral spread.\  Research into such phenomena is limited, there is still much to learn about when they occur and what their effect is on fire behavior.\  Currently there are no operational fire spread models that can accommodate these important effects. To account for these phenomena, it is first necessary to describe them and the conditions under which they occur, including fuel conditions, surface weather and atmospheric profiles.

This project is designed to build on our knowledge of the unique features of extreme fires by a) Collating observations of extreme fires that have occurred in Australia in recent years, b) Analysing fire phenomena in conjunction with accessory information (ie. Weather, fuel and topography) and c) Developing mathematical relationships to describe important fire phenomena.

}, issn = {133}, author = {Thomas Duff and Trent Penman} } @article {bnh-2241, title = {National Fire Danger Rating System Probabalistic Framework: year three report}, number = {116}, year = {2015}, month = {09/2015}, institution = {Bushfire and Natural Hazards CRC}, address = {Melbourne}, abstract = {

The objective of the Probabilistic Framework Project is to develop a new consequence-based fire danger rating system able to integrate a wide range of variables and link their complex interactions to the probability of property loss. The project aims at delivering a spatially-explicit framework capable of generating daily maps representing the distribution of the probability of property loss at 5km spatial resolution.

In year two, a {\textquotedblleft}consequence-based{\textquotedblright} system (developed in Year 1) was refined and applied in two case study regions: the Sydney Basin, and the Victorian East Central Risk Landscape. The BN framework was successfully integrated with GIS facilities to generate spatially explicit predictions of the probability of a fire spreading to and reaching the urban interface and then burning there at high intensity (\>4000kWm-1, hereafter unsuppressible fires). Overall, the model indicated that the highest risk areas may potentially be identified by accounting for not only fire weather, but also fuels, the distribution of property, plus features inherent in the landscape that influenced fire spread.

The objective for the third stage of the project was to develop and test an operational application of the daily fire danger rating Bayesian Network model for two case study areas - Sydney Basin and the East Central Risk Landscape in Victoria. In this report, we present the results of the operational application of the model, quantify sensitivities of the model and finally we make recommendations for the future of the modelling approach.
We developed a prototype Fire Danger Rating (FDR) website for updating fire risk in real-time (30-60 seconds per case study). Maps are generated through use of landscape data and additional daily 3pm weather data downloaded from the Bureau of Meteorology. Across the 2014/15 season spatial variation was seen between the predictions from the FDR and that of FFDI. It is important to note that these variations exist despite the fact FFDI is an input into the model influencing ignition probability, fire spread and fire intensity. One of the main reasons for these differences is that FFDI only accounts for weather and does not consider topography, fuels, spatial arrangement of assets or the directionality of the wind.

The sensitivity analysis suggested that the model is performing well relative to expectations. Logical relationships and coarse scale patterns are holding true. The results indicate strong reliance on the empirical analysis of ignition probabilities in the landscape. FFDI was found to be the input node that required the greatest accuracy.

A number of recommendations were made by state agencies during an end of study review of the project. These included expanding the FDR website to new landscapes, with particular interest in assessing the model for grassland environments. In addition, the group thought the model had considerable capacity for longer term planning of fuel treatments, accounting for changing human patterns and future climates.

Overall, the project has succeeded in delivering a spatially-explicit framework capable of generating daily maps representing the distribution of the probability of property loss at 5km spatial resolution.

}, issn = {116}, author = {Trent Penman and Parkins, K.A. and Mascaro, S. and Chong, Derek and Ross Bradstock} } @article {bnh-3845, title = {Reducing the risk of house loss due to wildfires}, journal = {Environmental Modelling and Software}, volume = {67}, year = {2015}, month = {05/2015}, pages = {12-25}, chapter = {12}, abstract = {

Wildfires will continue to reach people and property regardless of management effort in the landscape. House-based strategies are therefore required to complement the landscape strategies in order to reduce the extent of house loss. Here we use a Bayesian Network approach to quantify the relative influence of preventative and suppressive management strategies on the probability of house loss in Australia. Community education had a limited effect on the extent to which residents prepared their property hence a limited effect on the reduction in risk of house loss, however hypothetically improving property preparedness did reduce the risk of house loss. Increasing expenditure on suppression resources resulted in a greater reduction in the risk of loss than preparedness. This increase had an interaction effect with increasing the distance between vegetation and the houses. The extent to which any one action can be implemented is limited by social, environmental and economic factors.

}, doi = {10.1016/j.envsoft.2014.12.020}, url = {http://www.sciencedirect.com/science/article/pii/S1364815214003776?via\%3Dihub}, author = {Trent Penman and Ann E. Nicholson and Ross Bradstock and Luke Collins and Sandra H. Penman and Owen Price} } @article {bnh-1741, title = {Community Understanding and Awareness of Bushfire Safety: October 2013 Bushfires - Overview}, year = {2014}, abstract = {

This overview provides a consolidation of the findings from the interviews and online surveys conducted by the\ Bushfire CRC researcher into the community understanding of bushfire safety and responses in the context of the\ October 2013 Bushfires in NSW. This work was commissioned by NSW Rural Fire Service.\ This research had two separate {\textendash} but interconnected {\textendash} components, (i) a series of interviews with residents in\ a number of fire impacted communities, and (ii) an online survey (also targeted to those communities but open\ more broadly to fire impacted areas in NSW ) each of these has been analysed and reported upon in detail in the\ reports submitted. Both components focused on common themes and the following summarises the combined\ responses.\ 

The executive summaries from the two individual reports are provided at the end of the consolidated findings.

}, isbn = {978-0-9925027-3-7}, author = {Wright, Lyndsey and Jim McLennan and Birch, Adrian and Bronwyn Horsey and Trent Penman} } @article {bnh-1743, title = {Community Understanding and Awareness of Bushfire Safety: October 2013 Bushfires - Part 2}, year = {2014}, abstract = {

In October 2013, a number of large destructive bushfires resulted in the loss of property in the greater Sydney area. Following such events, it is important to liaise with the community to understand their actions on the day and what agency information was effective and what was not. Learning from these events means that management responses can be improved for future bushfires, hopefully resulting in a reduced loss of property and the ongoing protection of life.

The Centre for Environmental Risk Management at the University of Wollongong ran an extensive online survey for residents in the fire affected ares. \ 

}, isbn = {978-0-9925027-3-7}, author = {Bronwyn Horsey and Trent Penman} } @article {bnh-1360, title = {National Fire Danger Rating System Probabalistic Framework: year two report}, number = {008}, year = {2014}, abstract = {

Fire danger ratings in Australia currently rely heavily on McArthur{\textquoteright}s indices for forests and grasslands. Advances in fire and in meteorological science means that these indices do not adequately reflect current knowledge or recent technological advances. We now have the capability to provide information on fire danger at a much greater spatial and temporal resolution than previously, but do not fully utilise it. The indices are used for a wider range of purposes than originally envisaged, and growing societal expectations and changes in communication technology provide both the impetus and opportunity for a more detailed and more accurate service.

This is the final report for year two of this research project.

}, author = {Trent Penman and Bedward, M. and Ross Bradstock} } @article {BF-4272, title = {Environmental assessment of erosion following prescribed burning in the Mount Lofty Ranges, Australia}, journal = {International Journal of Wildland Fire}, year = {2013}, month = {10/2013}, abstract = {Erosion following fire has the potential to affect water quality, alter soil profiles and detrimentally affect human infrastructure. There is a clear need for environmental assessments to have regard for erosion concerns from prescribed burning. This study focussed on 10 prescribed burns conducted in the Southern Mount Lofty Ranges. Generalised additive modelling was used to determine the main significant environmental variables influencing the presence of sediment movement at 505 field-assessed sites. Sediment movement after the 10 prescribed burns was minor. Fire severity was a highly significant environmental determinant for the presence of sediment movement after prescribed burning. To predict erosion concerns, a suite of environmental variables is more reliable than focusing solely on slope steepness, as occurred before this study. These results indicate that erosion assessments need to consider a range of environmental variables to assess potential erosion and that land managers and scientists need to incorporate spatial sampling designs into erosion assessments.}, keywords = {bioturbation, erosion assessment, fire severity, rainfall, sediment movement, slope, topography}, doi = {http://dx.doi.org/10.1071/WF13011}, url = {http://www.publish.csiro.au/paper/WF13011.htm}, author = {Morris, Rowena and Ross Bradstock and Deirdre Dragovich and Henderson, M. K. and Trent Penman and Bertram Ostendorf} } @article {BF-3095, title = {Prescribed burning: how can it work to conserve the things we value?}, journal = {International Journal of Wildland Fire}, volume = {20}, year = {2011}, month = {2011}, pages = {721}, abstract = {Prescribed burning is a commonly applied management tool, and there has been considerable debate over the efficacy of its application. We review data relating to the effectiveness of prescribed burning in Australia. Specifically, we address two questions: (1) to what extent can fuel reduction burning reduce the risk of loss of human life and economic assets posed from wildfires? (2) To what extent can prescribed burning be used to reduce the risk of biodiversity loss? Data suggest that prescribed burning can achieve a reduction in the extent of wildfires; however, at such levels, the result is an overall increase in the total area of the landscape burnt. Simulation modelling indicates that fuel reduction has less influence than weather on the extent of unplanned fire. The need to incorporate ecological values into prescribed burning programmes is becoming increasingly important. Insufficient data are available to determine if existing programs have been successful. There are numerous factors that prevent the implementation of better prescribed burning practices; most relate to a lack of clearly defined, measurable objectives. An adaptive risk management framework combined with enhanced partnerships between scientists and fire-management agencies is necessary to ensure that ecological and fuel reduction objectives are achieved.}, doi = {10.1071/WF09131}, author = {Trent Penman and Christie, Fiona J. and Andersen, A. N. and Ross Bradstock and Geoffrey J. Cary and Henderson, M. K. and Owen Price and Tran, C. and Wardle, G. M. and Williams, RJ and York, Alan} } @article {2046, title = {Climate and recent fire history affect fuel loads in Eucalyptus forests: Implications for fire management in a changing climate}, journal = {Forest Ecology and Management}, volume = {260}, year = {2010}, month = {2010/10/15/}, pages = {1791 - 1797}, abstract = {Predicted changes to global climates are expected to affect natural fire regimes. Many studies suggest that the impact of these effects could be minimised by reducing fuel loads through prescribed burning. Fuel loads are dynamic and are affected by a range of factors including fire and climate. In this study, we use a 22-year dataset to examine the relative influence of climate and fire history on rates of litterfall and decomposition, and hence fuel loads, in a coastal Eucalypt forest in south-eastern Australia. Litterfall and decomposition were both affected by temperature, recent rainfall and fire history variables. Over the study period prescribed burning immediately reduced fuel loads, with fuel loads reaching pre-burn levels within 3 years of a fire. Modelling fuel loads under predicted climate change scenarios for 2070 suggests that while fuel loads are reduced, the levels are not significantly lower than those recorded in the study. Based on these predictions it is unlikely that the role or value of prescribed burning in these forests will change under the scenarios tested in this study. }, keywords = {Accumulation, Climate change, Decomposition, Forest management, Prescribed burning}, isbn = {0378-1127}, url = {http://www.sciencedirect.com/science/article/B6T6X-511H38D-1/2/2825befe9a608c7cb83a0a58406d25a8}, author = {Trent Penman and York, Alan} } @article {BF-2413, title = {Patch-Occupancy Modeling as a Method for Monitoring Changes in Forest Floristics: a Case Study in Southeastern Australia}, journal = {Conservation Biology}, volume = {23}, year = {2009}, month = {06/2009}, pages = {740 - 749}, abstract = {The ability to monitor changes in biodiversity is fundamental to demonstrating sustainable management practices of natural resources. Disturbance studies generally focus on responses at the plot scale, whereas landscape-scale responses are directly relevant to the development of sustainable forest management. Modeling changes in occupancy is one way to monitor landscape-scale responses. We used understory vegetation data collected over 16 years from a long-term study site in southeastern Australia. The site was subject to timber harvesting and frequent prescribed burning. We used occupancy models to examine the impacts of these disturbances on the distribution of 50 species of plants during the study. Timber harvesting influenced the distribution of 9 species, but these effects of harvesting were generally lost within 14 years. Repeated prescribed fire affected 22 species, but the heterogeneity of the burns reduced the predicted negative effects. Twenty-two species decreased over time independent of treatment, and only 5 species increased over time. These changes probably represent a natural response to a wildfire that occurred in 1973, 13 years before the study began. Occupancy modeling is a useful and flexible technique for analyzing monitoring data and it may also be suitable for inclusion within an adaptive-management framework for forest management.}, doi = {10.1111/j.1523-1739.2008.01146.x}, author = {Trent Penman and Binns, Doug L. and Kavanagh, Rodney P.} } @article {BF-2387, title = {Quantifying successional changes in response to forest disturbances}, journal = {Applied Vegetation Science}, volume = {11}, year = {2009}, month = {04/2008}, pages = {261 - 268}, abstract = {Question: Can dissimilarity measures of individual plots be used to forecast the driving factors among various anthropogenic disturbances influencing understorey successional changes? Location: Yambulla State Forest, south-eastern Australia (37{\textdegree}14{\textquoteright}S, 149{\textdegree}38{\textquoteright}E). Methods: Assessments of understorey vegetation communities were taken prior to anthropogenic disturbances and at three subsequent time periods representing a period of 15 years post-disturbance. Dissimilarities were calculated from the original assessment and modelled in a Bayesian framework to examine the influence of logging, number of prescribed burns and time. Results: All sites underwent significant changes over time independently of the imposed management regimes. Logging resulted in an immediate change in vegetation assemblage which decreased in the subsequent assessments. The number of prescribed fires brought greater change in the shrub vegetation assemblages, but less change in the ground species vegetation assemblages. Conclusions: The anthropogenic disturbances did have some role in the changes of vegetation assemblages but these were minimal. The ongoing changes appear to be a natural response to the last wildfire, which passed through the study area in 1973 (13 years prior to the study). Forest management practices should consider the influence of wildfire succession when planning for the conservation of biodiversity.}, issn = {14022001}, doi = {10.3170/2008-7-18424}, author = {Trent Penman and Binns, Doug L. and Kavanagh, Rodney P.} } @article {BF-2388, title = {Changes in understorey plant species richness following logging and prescribed burning in shrubby dry sclerophyll forests of south-eastern Australia}, journal = {Austral Ecology}, volume = {33}, year = {2008}, month = {04/2008}, pages = {197 - 210}, abstract = {The impacts of prescribed burning and timber harvesting on species diversity have been the subject of considerable debate. The temporal and spatial scale of these disturbances often presents major limitations to many studies. Here we present the medium-term results of a planned long-term study examining the impacts of logging and prescribed burning on the understorey floristic richness in shrubby dry sclerophyll forest in the south-east of New South Wales, Australia. Generalized estimating equations were used to model the effect of environmental factors and disturbance variables on species richness at the coupe (\~{}30 ha) and plot (\~{}0.01 ha) scale. At the plot scale, fire effects on separate components of the vegetation were broadly consistent with other studies, with frequent fire resulting in a relative increase of species richness for species less than 1 m in height and a decline of larger species taller than this height. At the coupe scale, there was no decline in richness of larger shrub species, possibly owing to the spatial heterogeneity of fire frequency at this scale. Logging resulted in significantly greater species richness in the shrub layer, but had no significant effect on species richness in the ground layer. During the study period, there was a general decline in plant species richness at both coupe and plot scales which occurred independently of imposed management regimes. This is thought to be related to a natural succession following wildfire, and may be due to the absence of high-intensity fire in the study area since 1973, or to an effect related to season of burning.}, doi = {10.1111/j.1442-9993.2007.01809.x}, author = {Trent Penman and Binns, Doug L. and Shiels, RJ and Allen, RM and Kavanagh, Rodney P.} } @article {BF-1111, title = {Germination responses of a dry sclerophyll forest soil stored seed bank to fire related cues.}, journal = {Cunninghamia}, number = {10}, year = {2008}, month = {12/02/2008}, pages = {547-555}, abstract = {Fire is an integral component of many ecosystems worldwide. Many plant species require fire related cues to trigger germination, primarily heat and smoke. Despite the importance of this process, the responses of many Australian species to these cues are unknown. Without this knowledge fire management strategies may be developed that are inappropriate for individual species and communities. In this study we examined the responses of a dry Eucalypt forest seed bank to heat and smoke germination cues. Analysis was possible for 48 taxa within the soil seed bank with 34 of these showing a response to one or both of the germination cues. Ten species responded to the heat treatment, eleven responded to the smoke treatment and thirteen species responded to both the heat and smoke treatments. Germination cues acted independently for all species considered. Results in this study were consistent with published reports for most species, although some differences were seen at the species and genus level. The study highlights the importance of fire-related cues in enhancing germination of a large proportion of the species occurring in dry Eucalypt forests.}, url = {http://www.dpi.nsw.gov.au/research/areas/fre/scientific-outputs/2008/1386}, author = {Trent Penman and Binns, Doug L. and Shiels, RJ and Allen, RM and Plummer, H} } @article {BF-2389, title = {Soil temperatures during autumn prescribed burning: implications for the germination of fire responsive species?}, journal = {International Journal of Wildland Fire}, volume = {17}, year = {2008}, month = {2008}, pages = {572}, abstract = {Prescribed fire is a widely applied management tool in native forests. There have been concerns raised about the ecological impacts of prescribed fire on native flora. One aspect of the debate is the extent to which prescribed fire heats the soil to levels reported to trigger germination in the soil seed banks. We used Thermochrons to test soil temperatures at 2 and 5 cm in prescribed burns in dry sclerophyll forests. Soil temperatures during the burns were generally low (<40{\textdegree}C) with less than 5\% of sites being exposed to temperatures necessary for the germination of fire-dependent shrub species. High temperatures were associated with high fuel consumption and large woody debris. This information suggests that prescribed fires, carried out according to standard practices, in these forests are unlikely to trigger germination in the majority of the soil-stored seed banks. If ecological burns in these forests are aimed at promoting populations of senescing obligate seeder species, they need to be hotter than standard practice if they are to achieve their objectives, although we acknowledge that there are inherent risks associated with hotter burns.}, doi = {10.1071/WF07092}, author = {Trent Penman and Towerton, AL} } @article {BF-1110, title = {The influence of prescribed burning on fruit production in Proteaceae}, journal = {Cunninghamia}, year = {2007}, author = {Trent Penman and Binns, Doug L. and Plummer, H} } @article {BF-2368, title = {Patchiness of prescribed burns in dry sclerophyll eucalypt forests in South-eastern Australia}, journal = {Forest Ecology and Management}, volume = {252}, year = {2007}, month = {11/2007}, pages = {24 - 32}, abstract = {Prescribed burning is commonly used in eucalypt forests to reduce fire risk and minimize damage to people and property in the event of a wildfire. The dry sclerophyll forests of south-eastern Australia are naturally fire-prone. Little is known about the heterogeneity of prescribed fires in these forests. This paper reports on the spatial variability of repeated low intensity fires under two burning regimes, in both logged and unlogged forests, for a 17-year period from 1988 to 2005. Prescribed burns were extremely patchy at both the coupe and the plot scale for all treatments. Burns implemented soon after logging covered significantly greater areas than the standard prescribed burns. On the coupe scale, the extent of the burn was influenced by the average aspect of the coupe and the percent of the coupe burnt in the last fire. At the smaller plot scale, the extent of the burn was influenced by the neighbourhood burn patterns, the distance the plot was from the nearest drainage line, the time since the last fire and the percentage of the plot that was burnt in the last fire. Under operational conditions, sites on ridges are likely to burn approximately every 11 years and sites in gullies approximately every 20 years. Patchy burns achieved in this study will provide refuges for fire sensitive species and newly burnt areas for colonizing species and are therefore likely to have significantly lower ecological impacts than homogenous burns.}, doi = {10.1016/j.foreco.2007.06.004}, author = {Trent Penman and Kavanagh, Rodney P. and Binns, Doug L. and Melick, DR} }