Owen Price

FIRE-STICK FORESTRY - A MATRIX MODEL IN SUPPORT OF SKILLFUL FIRE MANAGEMENT OF CALLITRIS-INTRATROPICA BAKER,R.T. BY NORTH AUSTRALIAN ABORIGINES

Publisher: JSTOR

Date: 11-1994

DOI: 10.2307/2846032

Regional patterns of mammal abundance and their relationship to landscape variables in eucalypt woodlands near Darwin, northern Australia

Publisher: CSIRO Publishing

Date: 2005

DOI: 10.1071/WR04033

Abstract: Habitat loss and fragmentation are usually construed as having negative consequences for wildlife, and habitat heterogeneity as having a positive effect. We conducted a mammal survey in eucalypt woodlands near Darwin, and found very few mammals in an intact region of the study area. This is consistent with an emerging pattern suggesting that many mammal species are declining across northern Australia, even though habitats remain relatively intact. However, we also found apparently healthy populations of the same species in a fragmented region of the study area. Using a combination of remote sensing, GIS and generalised linear modeling, we found some evidence of relationships between fire regime, fire heterogeneity or vegetation heterogeneity and the distributions of mammal species in this area. However, there was a strong regional component of the distribution that is not explained by these variables. The cause of the lack of mammals in the intact region of the study area has not been revealed by this analysis. One possible reason for this failure is that the landscape variables used in the analysis were too fine to detect variation in mammal abundance occuring at a much courser regional scale.

The carbon cost of the 2019–20 Australian fires varies with fire severity and forest type

Publisher: Wiley

Date: 28-05-2022

DOI: 10.1111/GEB.13548

Abstract: To estimate loss of above‐ground carbon (AGC) and conversion of live carbon to dead carbon following understorey and canopy fire. South‐eastern Australia. 2019–2020. Four widespread resprouting eucalypt forests. Above‐ground carbon was measured in 15 plots in each of four forest types one‐year post‐fire. We also assessed topkill, that is, trees subject to canopy loss that failed to resprout epicormically. While canopy fire was associated with greater declines in AGC than understorey fire, this was only statistically significant for only one forest type, where AGC declined from 154 to 85 Mg C ha −1 following canopy fire. Significant post‐fire increases in dead AGC were observed in one forest type, where dead carbon increased from 22 to 60% after canopy fire. Topkill of trees following canopy fire (48–78% of stems) was higher than topkill after understorey fire (36–53% of stems) and in unburnt forest (12–55%). Topkill occurred primarily in small‐diameter stems. Consequently, there was no effect of fire on the proportion of dead AGC in trees, with the exception of the forest with lowest productivity (i.e., lowest biomass) and lowest annual rainfall, where dead tree carbon increased from 8% in unburnt forest to 13 and 53% after understorey and canopy fire, respectively. AGC in understorey vegetation and coarse woody debris was similar or lower in burnt compared with unburnt forest. Litter carbon was significantly lower and pyrogenic carbon significantly higher in burnt forest, with no difference between understorey and canopy fire. While increased fire severity was associated with increased changes to carbon stocks, there were differences among forest types. Specifically, the driest forest type had the highest rates of topkill following canopy fire. These results highlight the importance of spatial variability in fire severity and forest type in determining the effects of fire on carbon stocks.

The influence of prescribed fire on the extent of wildfire in savanna landscapes of western Arnhem Land, Australia

Publisher: CSIRO Publishing

Date: 2012

DOI: 10.1071/WF10079

Abstract: Fire regimes in many north Australian savanna regions are today characterised by frequent wildfires occurring in the latter part of the 7-month dry season. A fire management program instigated from 2005 over 24 000 km2 of bio ersity-rich Western Arnhem Land aims to reduce the area and severity of late dry-season fires, and associated greenhouse gas emissions, through targeted early dry-season prescribed burning. This study used fire history mapping derived mostly from Landsat imagery over the period 1990–2009 and statistical modelling to quantify the mitigation of late dry-season wildfire through prescribed burning. From 2005, there has been a reduction in mean annual total proportion burnt (from 38 to 30%), and particularly of late dry-season fires (from 29 to 12.5%). The slope of the relationship between the proportion of early-season prescribed fire and subsequent late dry-season wildfire was ~–1. This means that imposing prescribed early dry-season burning can substantially reduce late dry-season fire area, by direct one-to-one replacement. There is some evidence that the spatially strategic program has achieved even better mitigation than this. The observed reduction in late dry-season fire without concomitant increase in overall area burnt has important ecological and greenhouse gas emissions implications. This efficient mitigation of wildfire contrasts markedly with observations reported from temperate fire-prone forested systems.

Reducing wildfire risk to urban developments: Simulation of cost-effective fuel treatment solutions in south eastern Australia

Publisher: No publisher found

Date: 2014

DOI: 10.1016/J.ENVSOFT.2013.09.030

Bayes Nets as a method for analysing the influence of management actions in fire planning

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/WF10076

Abstract: Wildfire can result in significant economic costs with inquiries following such events often recommending an increase in management effort to reduce the risk of future losses. Currently, there are no objective frameworks in which to assess the relative merits of management actions or the synergistic way in which the various combinations may act. We examine the value of Bayes Nets as a method for assessing the risk reduction from fire management practices using a case study from a forested landscape. Specifically, we consider the relative reduction in wildfire risk from investing in prescribed burning, initial or rapid attack and suppression. The Bayes Net was developed using existing datasets, a process model and expert opinion. We compared the results of the models with the recorded fire data for an 11-year period from 1997 to 2000 with the model successfully duplicating these data. Initial attack and suppression effort had the greatest effect on the distribution of the fire sizes for a season. Bayes Nets provide a holistic model for considering the effect of multiple fire management methods on the risk of wildfires. The methods could be further advanced by including the costs of management and conducting a formal decision analysis.

Global patterns in fire leverage: the response of annual area burnt to previous fire

Publisher: CSIRO Publishing

Date: 2015

DOI: 10.1071/WF14034

Abstract: Prescribed fire is practiced around the world to reduce the effect of unplanned fire, but we hypothesise that its effectiveness is proportional to the mean annual area burnt by unplanned fire, which varies among biomes. Fire history mapping was obtained for six global case studies from a range of biomes: Portugal, Spain (both Mediterranean), Alberta (boreal Canada), Sequoia and Kings Canyon National Parks (montane USA), the Sandy Desert (arid Australia) and Kruger National Park (South African savanna). Leverage is the unit reduction in unplanned fire area resulting from one unit of previous fire as measured at a regional scale over a long period. We calculated leverage for each case study using statistical modelling of annual area burnt, controlling for annual climatic variation. We combined the six leverage values with those from four previously published cases to conduct a global test of our hypothesis. Leverage was high in Portugal (~0.9) and moderate in the Sandy Desert (~0.3). However, the other case studies showed no evidence of leverage: burnt area was not influenced by past fire. In all regions, climatic variation had more influence than past area burnt on annual area burnt. The global analysis revealed a positive relationship between mean area burnt and leverage but only when outlying cases were removed. In biomes with low fire activity, prescribed fire is unlikely to reduce unplanned fire area at all, while for many others, the return for effort is likely to be low. Lessons derived from one biome cannot necessarily be applied to another.

Satellite-based comparison of fire intensity and smoke plumes from prescribed fires and wildfires in south-eastern Australia

Publisher: CSIRO Publishing

Date: 2013

DOI: 10.1071/WF11165

Abstract: Smoke pollution from wildfires can adversely affect human health, and there is uncertainty about the amount of smoke pollution caused by prescribed v. wildfires, a problem demanding a landscape perspective given that air quality monitoring is sparse outside of urban airsheds. The primary objective was to assess differences in fire intensity and smoke plume area between prescribed fires and wildfires around Melbourne and Sydney, Australia. We matched thermal anomaly satellite data to databases of fires in forests surrounding both cities. For each matched fire we determined hotspot count and quantified their intensity using the fire radiative power (FRP) measurement. Smoke plumes were mapped using MODIS true colour images. Wildfires had more extreme fire intensity values than did prescribed burns and the mean size of wildfire plumes was six times greater than of prescribed fire plumes for both cities. Statistical modelling showed that the horizontal area covered by smoke plumes could be predicted by hotspot count and sum of FRP, with differences between cities and fire type. Smoke plumes from both fire types reached both urban areas, and particulate pollution was higher on days affected by smoke plumes. Our results suggested that prescribed fires produced smaller smoke plume areas than did wildfires in two different flammable landscapes. Smoke plume and FRP data, combined with air pollution data from static monitors, can be used to improve smoke management for human health.

Role of weather and fuel in stopping fire spread in tropical savannas

Publisher: Wiley

Date: 29-01-2014

DOI: 10.1111/AEC.12021

EARLY DEVELOPMENT AND POPULATION FLUCTUATIONS IN SOAY SHEEP

Publisher: JSTOR

Date: 06-1992

DOI: 10.2307/5330

The 'wilderness effect' and the decline of Callitris intratropica on the Arnhem Land Plateau, northern Australia

Publisher: CSIRO Publishing

Date: 2001

DOI: 10.1071/BT00087

Abstract: An aerial survey along a transect from eastern side of the Arnhem Land Plateau where Aboriginal people still lead a semi-traditional lifestyle, to the unoccupied western side of the Plateau, revealed systematic differences in the proportion of living and dead Callitris intratropica trees. Multiple regression analysis showed that the highest proportion of dead C. intratropica stems occurred on unoccupied, level terrain dominated by open Eucalyptus forests, with a minor or complete absence of Allosyncarpia ternata closed-canopy forests. A detailed study of one population of C. intratropica in western Arnhem Land adjacent to a small patch of A. ternata forest, known as Round Jungle, showed that the population had a unimodal size-class distribution, reflecting a low density of stems less than 10 cm in diameter at breast height (dbh). A computer simulation model was developed on the basis of estimates of annual fecundity, mortality and growth rates derived from observations of the stand. Sensitivity analyses suggested that a well-stocked stand could be transformed to one similar to that observed at Round Jungle after 50 years, if annual mortality rate of the immature stems (i.e. cm dbh) was greater than 85%. Under these conditions, the stand would become extinct after 325 years. Variation in estimates of mature-stem ( cm dbh) mortality and fecundity had much less effect on the predictions of the model than the rate of mortality of the smallest size class. The model suggests that C. intratropica populations can rapidly fluctuate in response to changes in fire regime, while extinction is a gradual process and is consequently unlikely if some seedlings can escape burning, for instance by establishing in fire-protected microsites. This conclusion is consistent with the observed greater mortality of C. intratropica on sand sheets that have little topographic variability at the micro- or mesoscale, compared with other habitat types in areas that are currently unoccupied by Aboriginal people. Our study shows that predicting the fate of in idual populations will require careful consideration of local factors such as the presence of micro-topographically safe sites for seedling establishment, as well as the surrounding pattern of vegetation and landforms that mediate the impact of fire on C. intratropica. However, we suggest that rather than refining details of the adjustment of C. intratropica in response to changed fire regimes associated with European colonisation, subsequent research should focus on the effect and significance of these changes for other organisms.

Logging and Fire in Australian Forests: errors by Attiwill et al. (2014)

Publisher: Wiley

Date: 12-02-2014

DOI: 10.1111/CONL.12086

PATTERNS OF SPECIES COMPOSITION AND RESERVE DESIGN FOR A FRAGMENTED ESTATE - MONSOON RAIN-FORESTS IN THE NORTHERN-TERRITORY, AUSTRALIA

Publisher: Elsevier BV

Date: 1995

DOI: 10.1016/0006-3207(94)00123-8

Very large area requirements for frugivorous birds in monsoon rainforests of the Northern Territory, Australia

Publisher: Elsevier BV

Date: 12-1999

DOI: 10.1016/S0006-3207(99)00081-6

Wildfires: Weigh policy effectiveness

Publisher: American Association for the Advancement of Science (AAAS)

Date: 20-11-2015

DOI: 10.1126/SCIENCE.350.6263.920-A

Positive severity feedback between consecutive fires in dry eucalypt forests of southern Australia

Publisher: Wiley

Date: 03-2018

DOI: 10.1002/ECS2.2110

The Drivers of Effectiveness of Prescribed Fire Treatment

Publisher: Oxford University Press (OUP)

Date: 09-12-2012

DOI: 10.5849/FORSCI.11-002

Suppression resource decisions are the dominant influence on containment of Australian forest and grass fires

Publisher: Elsevier BV

Date: 12-2018

DOI: 10.1016/J.JENVMAN.2018.09.031

Abstract: Fire agencies aim to contain wildfires before they impact on life, property and infrastructure and to reduce the risk of damage to the environment. Despite the large cost of suppression, there are few data on the success of suppression efforts under varying weather, fuel and resource scenarios. We examined over 2200 forest and 4600 grass fires in New South Wales, Australia to determine the dominant influences on the containment of wildfires. A random forest modelling approach was used to analyse the effect of a range of human and environmental factors. The number of suppression resources per area of fire were the dominant influence on the containment of both forest and grass fires. As fire weather conditions worsened the probability of containment decreased across all fires and as fuel loads and slope increased the probability of containment decreased for forest fires. Environmental controls limit the effectiveness of wildfire management. However, results suggest investment in suppression resources and strategic fuel management will increase the probability of containment.

Some Wildfire Ignition Causes Pose More Risk of Destroying Houses than Others

Publisher: Public Library of Science (PLoS)

Date: 06-09-2016

DOI: 10.1371/JOURNAL.PONE.0162083

High severity fire promotes a more flammable eucalypt forest structure

Publisher: Wiley

Date: 09-12-2022

DOI: 10.1111/AEC.13134

Abstract: Recent landscape‐scale wildfires in eastern Australia have made apparent the need for a greater understanding of the flammability dynamics of forested ecosystems. Fire severity is a measure of the impact of a fire on vegetation, but little is known about the landscape‐scale response of the fire‐prone dry sclerophyll forests of eastern Australia to different levels of fire severity. Species in these forests have multiple responses to fire, which can be dependent on the fire severity. In this study, we aimed to determine the effect of fire severity on the vegetation structure, and therefore flammability, of these forests. We addressed two hypotheses that 1) High severity fire would result in a denser understory than low severity fire after 5 years and that 2) High severity fire would reduce the vertical separation between understory and canopy after 5 years. Field surveys of 38 forest sites with differing fire severity but standardised time since fire and forest type, in Sydney region of New South Wales, Australia, were used to test these hypotheses. We found lower canopy cover and greater understory cover (0.5–4 m height) after high severity fire compared with sites which burnt at low severity. Vertical separation was less between the canopy and understory at sites after high severity fire than after low severity fire. The greater quantity of understory fuel and greater vertical continuity in fuel structure observed suggests a potential increase in forest flammability after high severity fire compared with lower severity fires in these forest types.

Divergent responses of fire to recent warming and drying across south-eastern Australia

Publisher: Wiley

Date: 28-03-2014

DOI: 10.1111/GCB.12449

Abstract: The response of fire to climate change may vary across fuel types characteristic of differing vegetation types (i.e. litter vs. grass). Models of fire under climatic change capture these differing potential responses to varying degrees. Across south-eastern Australia, an elevation in the severity of weather conditions conducive to fire has been measured in recent decades. We examined trends in area burned (1975-2009) to determine if a corresponding increase in fire had occurred across the erse range of ecosystems found in this part of the continent. We predicted that an increase in fire, due to climatic warming and drying, was more likely to have occurred in moist, temperate forests near the coast than in arid and semiarid woodlands of the interior, due to inherent contrasts in the respective dominant fuel types (woody litter vs. herbaceous fuels). Significant warming (i.e. increased temperature and number of hot days) and drying (i.e. negative precipitation anomaly, number of days with low humidity) occurred across most of the 32 Bioregions examined. The results were mostly consistent with predictions, with an increase in area burned in seven of eight forest Bioregions, whereas area burned either declined (two) or did not change significantly (nine) in drier woodland Bioregions. In 12 woodland Bioregions, data were insufficient for analysis of temporal trends in fire. Increases in fire attributable mostly to warming or drying were confined to three Bioregions. In the remainder, such increases were mostly unrelated to warming or drying trends and therefore may be due to other climate effects not explored (e.g. lightning ignitions) or possible anthropogenic influences. Projections of future fire must therefore not only account for responses of different fuel systems to climatic change but also the wider range of ecological and human effects on interactions between fire and vegetation.

Fire severity influences the post‐fire habitat structure and abundance of a cool climate lizard

Publisher: Wiley

Date: 13-08-2023

DOI: 10.1111/AEC.13410

Abstract: In the spring and summer of 2019–2020, the ‘Black Summer’ bushfires burned more than 97 000 km 2 of predominantly Eucalyptus dominated forest habitat in eastern Australia. The Black Summer bushfires prompted great concern that many species had been imperilled by the fires. Here, we investigate the effects that fire severity had on the habitat and abundance of a cool climate lizard Eul rus tympanum that was identified as a species of concern because 37% of its habitat was burnt in the Black Summer bushfires. We quantified habitat structure and the abundance of E. tympanum at sites which were unburnt, burnt at low severity and at high severity 10, 15 and 23 months after the fires. Our classification of fire severity based on scorch height and canopy status corresponded well with the Australian Government Google Earth Engine Burnt Area Map (AUS GEEBAM) fire severity layer. Ten months after the fires, sites burnt at high severity had less canopy cover, more bare ground and less fine fuel than sites burnt at low severity or unburnt sites. The abundance of E. tympanum varied with survey occasion and was greatest during the warmest s ling period and lowest during the coolest s ling period. The abundance of E. tympanum was consistently lower on sites burnt at high severity than sites burnt at low severity or unburnt sites. Our findings show that higher severity fires had a greater effect on E. tympanum than low severity fires. Our results suggest that E. tympanum were likely to have persisted in burnt sites, with populations in low severity and unburnt sites facilitating population recovery in areas burnt at high severity. Our results also suggest that wildfire impacts on E. tympanum populations will increase because the frequency and extent of severe fires are expected to increase due to climate change.

PERSISTENT INSTABILITY AND POPULATION REGULATION IN SOAY SHEEP

Publisher: JSTOR

Date: 06-1991

DOI: 10.2307/5300

Quantifying the influence of fuel age and weather on the annual extent of unplanned fires in the Sydney region of Australia

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/WF10016

Abstract: Planned fire is used globally to minimise the risk of unplanned fire, but it is important to measure the return for effort in terms of the reduction of risk per unit area of planned fire. Here, we use 30 years of fire mapping from four subregions of the Sydney region to compare the annual extent of unplanned fire with previous planned and unplanned fire. Using linear mixed modelling, we were able to discriminate the relative influence of previous fire, seasonal rainfall and weather during the peak fire season. The mean annual area burnt over the period was 4.11%, comprising 0.53% planned and 3.58% unplanned. We found that weather during the fire season was the most influential factor. Annual rainfall had a modest negative relationship with unplanned fire area. Past fire had some influence, but the relationship implied that approximately three units of planned fire are required to reduce the unplanned fire area by one unit. Managers would need to burn 5.4% per year to halve unplanned fire extent, a ten-fold increase on recent levels. This would increase the total area burnt, and have other effects that need to be considered (from smoke and greenhouse gas emissions, and changes to bio ersity).

The Relationship between Particulate Pollution Levels in Australian Cities, Meteorology, and Landscape Fire Activity Detected from MODIS Hotspots

Publisher: Public Library of Science (PLoS)

Date: 11-10-2012

DOI: 10.1371/JOURNAL.PONE.0047327

Future changes in climatic water balance determine potential for transformational shifts in Australian fire regimes

Publisher: IOP Publishing

Date: 06-2016

DOI: 10.1088/1748-9326/11/6/065002

Smoke Patterns around Prescribed Fires in Australian Eucalypt Forests, as Measured by Low-Cost Particulate Monitors

Publisher: MDPI AG

Date: 23-10-2021

DOI: 10.3390/ATMOS12111389

Abstract: Prescribed burns produce smoke pollution, but little is known about the spatial and temporal pattern because smoke plumes are usually small and poorly captured by State air-quality networks. Here, we s led smoke around 18 forested prescribed burns in the Sydney region of eastern Australia using up to 11 Nova SDS011 particulate sensors and developed a Generalised Linear Mixed Model to predict hourly PM2.5 concentrations as a function of distance, fire size and weather conditions. During the day of the burn, PM2.5 tended to show hourly exceedances (indicating poor air quality) up to ~2 km from the fire but only in the downwind direction. In the evening, this zone expanded to up to 5 km and included upwind areas. PM2.5 concentrations were higher in still, cool weather and with an unstable atmosphere. PM2.5 concentrations were also higher in larger fires. The statistical model confirmed these results, identifying the effects of distance, period of the day, wind angle, fire size, temperature and C-Haines (atmospheric instability). The model correctly identified 78% of hourly exceedance and 72% of non-exceedance values in retained test data. Applying the statistical model predicts that prescribed burns of 1000 ha can be expected to cause air quality exceedances over an area of ~3500 ha. Cool weather that reduces the risk of fire escape, has the highest potential for polluting nearby communities, and fires that burn into the night are particularly bad.

The influence of planting size and configuration on landscape fire risk

Publisher: Elsevier BV

Date: 10-2019

DOI: 10.1016/J.JENVMAN.2019.109338

Abstract: Revegetating cleared land with native trees and shrubs is increasingly used as a means of addressing loss of bio ersity, degraded soil and water resources and sequestration of carbon. However, revegetation also brings a potential to alter fire risk due to changing fuel types across the landscape. Previous research has found that increasing the area of revegetation does not increase the risk of fire at a landscape scale, but it remains unclear whether the design of revegetation can be optimised to minimise risk. We evaluated if size and arrangement of revegetation affects fire size and intensity within an agricultural setting using a simulation modelling approach. Three revegetation planting designs were assessed, including small (3.2 ha) dispersed plantings, small (3.2 ha) plantings clustered into one third of the landscape, and large (29.2 ha) dispersed plantings, all resulting in the same overall percentage of revegetation (approximately 10% of the landscape). We simulated fires using Phoenix Rapidfire under varying planting design, weather, surrounding pasture conditions, and fire suppression. Planting design had little effect on fire sizes across the landscape, with larger plantings resulting in slightly larger fire sizes. Fires were smaller in landscapes with all planting designs compared with current landscape patterns. There was no significant influence of planting design on fire intensity. Weather and suppression had the strongest influence on both fire size and intensity, with larger and more intense fires under extreme weather conditions, with higher adjacent pasture loads and with no simulated suppression. Management of fuel loads in the pasture surrounding revegetation, weather and suppression are far greater risk factors for fire in these landscapes than planting design.

What Do the Australian Black Summer Fires Signify for the Global Fire Crisis?

Publisher: MDPI AG

Date: 17-12-2021

DOI: 10.3390/FIRE4040097

Abstract: The 2019–20 Australian fire season was heralded as emblematic of the catastrophic harm wrought by climate change. Similarly extreme wildfire seasons have occurred across the globe in recent years. Here, we apply a pyrogeographic lens to the recent Australian fires to examine the range of causes, impacts and responses. We find that the extensive area burnt was due to extreme climatic circumstances. However, antecedent hazard reduction burns (prescribed burns with the aim of reducing fuel loads) were effective in reducing fire severity and house loss, but their effectiveness declined under extreme weather conditions. Impacts were disproportionately borne by socially disadvantaged regional communities. Urban populations were also impacted through prolonged smoke exposure. The fires produced large carbon emissions, burnt fire-sensitive ecosystems and exposed large areas to the risk of bio ersity decline by being too frequently burnt in the future. We argue that the rate of change in fire risk delivered by climate change is outstripping the capacity of our ecological and social systems to adapt. A multi-lateral approach is required to mitigate future fire risk, with an emphasis on reducing the vulnerability of people through a reinvigoration of community-level capacity for targeted actions to complement mainstream fire management capacity.

Countervailing effects of urbanization and vegetation extent on fire frequency on the Wildland Urban Interface: Disentangling fuel and ignition effects

Publisher: Elsevier BV

Date: 10-2014

DOI: 10.1016/J.LANDURBPLAN.2014.06.013

Wildfires, fuel treatment and risk mitigation in Australian eucalypt forests: Insights from landscape-scale simulation

Publisher: Elsevier BV

Date: 08-2012

DOI: 10.1016/J.JENVMAN.2012.03.050

Abstract: Wildfires pose significant risks to people and human infrastructure worldwide. The treatment of fuel in landscapes may alter these risks but the magnitude of this effect on risk is poorly understood. Evidence from Australian Eucalyptus forests suggests that mitigation of risk using prescribed burning as a fuel treatment is partial because weather and fuel dynamics are conducive to regular high intensity fires. We further examine the response of risk to treatment in eucalypt forests using landscape simulation modelling. We model how five key measures of wildfire activity that govern risk to people and property may respond to variations in rate and spatial pattern of prescribed fire. We then model effects of predicted climate change (2050 scenarios) to determine how the response of risk to treatment is likely to be altered in the future. The results indicate that a halving of risk to people and property in these forests is likely to require treatment rates of 7-10% of the area of the landscape per annum. Projections of 2050 weather conditions under climate change further substantially diminished the effect of rate of treatment. A large increase in rates of treatment (i.e. circa. 50% over current levels) would be required to counteract these effects of climate change. Such levels of prescribed burning are unlikely to be financially feasible across eucalypt dominated vegetation in south eastern Australia. Despite policy imperatives to expand fuel treatment, a reduction rather than an elimination of risk will result. Multi-faceted strategies will therefore be required for the management of risk.

Landscape Scale Influences of Forest Area and Housing Density on House Loss in the 2009 Victorian Bushfires

Publisher: Public Library of Science (PLoS)

Date: 29-08-2013

DOI: 10.1371/JOURNAL.PONE.0073421

Comparing the height and area of wild and prescribed fire particle plumes in south-east Australia using weather radar

Publisher: CSIRO Publishing

Date: 2018

DOI: 10.1071/WF17166

Abstract: Smoke pollution from landscape fires is a major health issue. Prescribed burning aims to reduce the area and impact of wildfire, but itself produces smoke pollution. This raises the question as to whether the smoke production and transport from prescribed fires is substantially different compared to wildfires. We examined the maximum height, width and areal footprint of large-particle plumes from 97 wild and 126 prescribed fires in south-eastern Australia using the existing network of weather radars. Radar detects large particles in smoke (probably those μm) and hence is an imperfect proxy for microfine ( μm) particles that are known to affect human health. Of the 223 landscape fires, ~45% of plumes were detected, with the probability being .8 for large fires ( 000 ha) regardless of type, closer than 50 km from the radar. Plume height was strongly influenced by fire area, the height of the planetary boundary layer and fire type. Plume heights differed between wildfire (range 1016–12 206 m, median 3260 m) and prescribed fires (range 706–6397 m, median 1669 m), and prescribed fires were predicted to be 800–1200 m lower than wildfires, controlling for other factors. For both wildfires and prescribed fires, the maximum plume footprint was always near the ground.

Biogeographical variation in the potential effectiveness of prescribed fire in south-eastern Australia

Publisher: Wiley

Date: 02-09-2015

DOI: 10.1111/JBI.12579

Managing the matrix: decadal responses of eucalypt-dominated savanna to ambient fire regimes

Publisher: Wiley

Date: 09-2010

DOI: 10.1890/09-1553.1

Abstract: Much of our understanding of the response of savanna systems to fire disturbance relies on observations derived from manipulative fire plot studies. Equivocal findings from both recent Australian and African savanna fire plot assessments have significant implications for informing conservation management and reliable estimation of biomass stocks and dynamics. Influential northern Australian replicated fire plot studies include the 24-year plot-scale Munmarlary and the five-year catchment-scale Kapalga, mesic savanna (> 1000 mm/yr of rainfall) experiments in present-day Kakadu National Park. At Munmarlary, under low-to-moderate-intensity fire treatments, woody vegetation dominated by mature eucalypts was found to be structurally stable. At Kapalga, substantial declines in woody biomass were observed under more intense fire treatments, and modeling assessments implicate early-season fires as having adverse effects on longer-term tree recruitment. Given these contrasting perspectives, here we take advantage of a landscape-scale fire response monitoring program established on three major northern Australian conservation reserves (Kakadu, Litchfield, and Nitmiluk National Parks). Using statistical modeling we assess the decadal effects of ambient fire regime parameters (fire frequency, severity, seasonality, time since fire) on 32 vegetation structure components and abundance of 21 tree and 16 grass species from 122 monitoring plots. Over the study period the mean annual frequency of burning of plots was 0.53, comprising mostly early-dry-season, low-severity fires. Structural and species responses were variable but often substantial, notably resulting in stem recruitment and declines in juveniles, but only weakly explained by fire regime and habitat variables. Modeling of these observations under three realistic scenarios (increased fire severity under projected worsening climate change modest and significant reductions in fire frequency to meet conservation criteria) indicates that all scenarios have positive and negative structural implications. Effecting significant regional fire regime change (e.g., reduction in frequency and size of severe fires) is demonstrably feasible, but it incurs risks and potentially some undesirable structural consequences. Given recent Australian and African experience, the generality and application of landscape-scale implications derived from manipulative fire assessments (including variable grazing and browsing regimes) in savanna require more critical assessment.

Resolving future fire management conflicts using multicriteria decision making

Publisher: Wiley

Date: 02-11-2016

DOI: 10.1111/COBI.12580

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 bio ersity 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, bio erse, and flammable wildland-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 bio ersity 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.

Fire heterogeneity in Kakadu National Park, 1980-2000

Publisher: CSIRO Publishing

Date: 2005

DOI: 10.1071/WR03043

Abstract: Although it is generally acknowledged that fire-induced heterogeneity is important for maintaining erse species assemblages in northern Australian savannas, scant relevant data are currently available to examine this proposition. The study takes advantage of a singular, detailed, bidecadal fire history assembled annually for Kakadu National Park to explore relationships between fire-induced heterogeneity and other terrain features. Three patch-based heterogeneity indices were calculated from assembled fire-history data for the central 1-ha cell of a 5 × 5 cell (25 ha) window that is, at a spatial scale relevant to the home ranges of many small- to medium-sized native mammals. Two of these indices were first calculated separately for each year, employing different metrics based on the extent of burning occurring in the 5 × 5 cell array, and then averaged for each of four consecutive five-year periods and over all years. The third index was calculated as the sum of the coefficients of variation for four fire-regime variability parameters determined likewise for five- and 20-year periods. Assembled data illustrate that (1) fire-induced heterogeneity in Kakadu increased in each successive five-year period from 1981, and (2) when modelled with independent terrain coverages, significant relationships were obtained for all three heterogeneity indices with terrain roughness, distance to roads, and distance to drainage lines.

Land management affects grass biomass in the Eucalyptus tetrodonta savannas of monsoonal Australia

Publisher: Wiley

Date: 08-05-2007

DOI: 10.1111/J.1442-9993.2007.01713.X

Modelling the potential for prescribed burning to mitigate carbon emissions from wildfires in fire-prone forests of Australia

Publisher: CSIRO Publishing

Date: 2012

DOI: 10.1071/WF11023

Abstract: Prescribed fire can potentially reduce carbon emissions from unplanned fires. This potential will differ among ecosystems owing to inherent differences in the efficacy of prescribed burning in reducing unplanned fire activity (or ‘leverage’, i.e. the reduction in area of unplanned fire per unit area of prescribed fire). In temperate eucalypt forests, prescribed burning leverage is relatively low and potential for mitigation of carbon emissions from unplanned fires via prescribed fire is potentially limited. Simulations of fire regimes accounting for non-linear patterns of fuel dynamics for three fuel types characteristic of eucalypt forests in south-eastern Australia supported this prediction. Estimated mean annual fuel consumption increased with diminishing leverage and increasing rate of prescribed burning, even though average fire intensity (prescribed and unplanned fires combined) decreased. The results indicated that use of prescribed burning in these temperate forests is unlikely to yield a net reduction in carbon emissions. Future increases in burning rates under climate change may increase emissions and reduce carbon sequestration. A more detailed understanding of the efficacy of prescribed burning and dynamics of combustible biomass pools is required to clarify the potential for mitigation of carbon emissions in temperate eucalypt forests and other ecosystems.

OVERCOMPENSATION AND POPULATION-CYCLES IN AN UNGULATE

Publisher: Springer Science and Business Media LLC

Date: 02-1992

DOI: 10.1038/355823A0

Abstract: Although theoretical studies show that overcompensatory density-dependent mechanisms can potentially generate regular or chaotic fluctuations in animal numbers, the majority of realistic single-species models of invertebrate populations are not overcompensatory enough to cause sustained population cycles. The possibility that overcompensation may generate cycles or chaos in vertebrate populations has seldom been considered. Here we show that highly overcompensatng density-dependent mortality can generate recurrent population crashes consistent with those observed in a naturally limited population of Soay sheep. The observed interval of three or more years between crashes points to sharp 'focusing' of mortality over a narrow range of population density.

Air Quality Impacts of Smoke from Hazard Reduction Burns and Domestic Wood Heating in Western Sydney

Publisher: MDPI AG

Date: 17-09-2019

DOI: 10.3390/ATMOS10090557

Abstract: Air quality was measured in Auburn, a western suburb of Sydney, Australia, for approximately eighteen months during 2016 and 2017. A long open-path infrared spectrometer s led path-averaged concentrations of several gaseous species, while other pollutants such as PM 2.5 and PM 10 were s led by a mobile air quality station. The measurement site was impacted by a number of indoor wood-heating smoke events during cold winter nights as well as some major smoke events from hazard reduction burning in the spring of 2017. In this paper we compare the atmospheric composition during these different smoke pollution events and assess the relative overall impact on air quality from domestic wood-heaters and prescribed forest fires during the c aign. No significant differences in the composition of smoke from these two sources were identified in this study. Despite the hazard reduction burning events causing worse peak pollution levels, we find that the overall exposure to air toxins was greater from domestic wood-heaters due to their higher frequency and total duration. Our results suggest that policy-makers should place a greater focus on reducing wood-smoke pollution in Sydney and on communicating the issue to the public.

Landscapes without boundaries: wildlife and their environments in northern Australia

Publisher: CSIRO Publishing

Date: 2005

DOI: 10.1071/WR03008

Abstract: This paper provides an introduction to the ecological fabric of northern Australia, described here as being a land characterised by extreme climatic seasonality and largely devoid of marked topographic features. Largely as a result of the latter trait, many species have extensive geographic ranges, and the spatial turnover in species composition is extremely limited. Somewhat counter-intuitively, these two traits can be accommodated by organisms only through reliance on critical, but often subtle, landscape variation. We present some preliminary models for Gouldian finch (Erythrura gouldiae) and black-footed tree-rat (Mesembriomys gouldii) to illustrate patterns of variation in their resource availability, and the consequences of such variation. We discuss briefly some studies that have attempted to integrate, or at least consider, these elements.

A transdisciplinary approach to understanding the health effects of wildfire and prescribed fire smoke regimes

Publisher: IOP Publishing

Date: 12-2016

DOI: 10.1088/1748-9326/11/12/125009

Efficacy of permanent firebreaks and aerial prescribed burning in western Arnhem Land, Northern Territory, Australia

Publisher: CSIRO Publishing

Date: 2007

DOI: 10.1071/WF06039

Abstract: We investigated the efficacy of firebreaks in the prevention of wildfires in the Arnhem Land Plateau, a vast, rugged and sparsely populated region with high bio ersity value and frequent wildfires. A total of 623 events where a fire met a permanent firebreak (cliffs, stream order, tracks and roads) in different fire seasons were compiled. Cliffs were more effective than streams at stopping fires, which were more effective than roads. Larger streams were more effective than small ones. The largest streams stop 75% of early dry season fires, but there are no firebreak types with more than 50% likelihood of stopping a late dry season fire. Geographic Information System (GIS) surfaces of the relative density of the three firebreak features in the landscape were randomly s led and compared with the total number of fires and late dry season fires using generalised linear modelling. Several of the density variables were weakly but significantly related to fire frequency, and it appears that late dry season fires are influenced by features at a larger scale (16-km radius) than total fires (4 km). The Aerial Prescribed Burning program for 2004 was studied to identify how effective it was at stopping subsequent wildfires by iding ignition lines into 137 5-km sections. Only 20% of sections achieved a 100% burn and where gaps occurred, a subsequent fire was 88% likely to penetrate the line. Firebreaks are not certain instruments for fire management in this area.

Fine-scale patchiness of different fire intensities in sandstone heath vegetation in northern Australia

Publisher: CSIRO Publishing

Date: 2003

DOI: 10.1071/WF03040

Abstract: We assessed the extent of burning and rockiness in 3712 5 × 5 m quadrats along 9.2 km of transects s ling five different fires in sandstone heaths where contemporary fire regimes are thought to be reducing the populations of many plants. All fires were patchy, with means of 64% burnt for early dry season and 84% for late dry season fires. Rockiness was strongly related to the presence of unburned patches, and some late dry season fires leave no patches in the absence of rocks. Half of the unburned patches were 10 m or less in length and of the 83 patches identified only three were still detectable when data were amalgamated into quadrats of 500 m2. Thus, very few patches could be recognised from satellite images. The results suggest that fires are much more patchy than satellite-derived fire maps indicate. This has important implications for understanding how populations of fire sensitive plants will respond to different fire regimes.

Adding fuel to the fire? Revegetation influences wildfire size and intensity

Publisher: Elsevier BV

Date: 03-2015

DOI: 10.1016/J.JENVMAN.2014.11.009

Abstract: The regrowth of woody vegetation in cleared landscapes (i.e. revegetation) has the potential to dramatically alter the spatial characteristics of vegetation and fuels, which will potentially alter fire characteristics. Understanding how revegetation alters fire size and intensity will be critical in determining the social and environmental value of revegetation. We used simulation modelling to examine (i) whether increasing native woody vegetation extent across landscapes cleared for pasture (i.e. revegetation) affects fire size and median fireline intensity and (ii) whether fuel load in the pasture matrix, the initial extent of land clearing and weather conditions during a fire alter the direction and/or magnitude of the relationships between revegetation and fire size or intensity. Simulations revealed that fire size and intensity were altered by increasing woody vegetation extent, though the direction of change was dependent upon landscape context. Increased woody vegetation extent led to (i) increased fire size in landscapes with low pasture fuel load (2 t ha(-1)) regardless of the extent of land clearing, (ii) decreased fire size in highly cleared landscapes with moderate (4.5 t ha(-1)) and high (7 t ha(-1)) pasture fuel load, and (iii) little change to fire size in landscapes subjected to low levels of clearing when pasture fuel load was moderate or high. Similar patterns were observed for fireline intensity. The magnitude of change in fire size and intensity was greatest under extreme fire weather conditions. Revegetation rarely increased median fireline intensity beyond suppressible levels (i.e. 4000 kW m(-1)), with fire weather and pasture fuel load being the main determinants of suppression potential. Our findings show that the response of fire size and intensity to revegetation will depend on landscape scale pasture management.

Short‐term impacts of the 2019–20 fire season on biodiversity in eastern Australia

Publisher: Wiley

Date: 17-10-2023

DOI: 10.1111/AEC.13247

Abstract: To address uncertainties surrounding the impacts of unprecedented 2019–20 bushfires in south‐eastern Australia, we convened a symposium on field‐measured impacts on bio ersity for the 2020 Ecological Society of Australia conference. Nine presentations covered a range of studies on plant species and communities, and reptiles and mammals. Here, we summarize the presentations and review other field studies from NSW, some of which are currently unpublished. The impacts were extensive, but results also estimated survival rate perhaps higher than first reported in the media. More than half of in idual mammal, reptile and threatened rainforest trees may have survived the fire, though small populations remain very vulnerable to second fire in the near future. Comprehensive understanding of the impacts of these fires requires much more field study, and for the results to be interpreted in the context of the broader fire regime. The symposium was an important early step in that understanding.

The drivers of wildfire enlargement do not exhibit scale thresholds in southeastern Australian forests

Publisher: Elsevier BV

Date: 10-2016

DOI: 10.1016/J.JENVMAN.2016.06.033

Abstract: Wildfires are complex adaptive systems, and have been hypothesized to exhibit scale-dependent transitions in the drivers of fire spread. Among other things, this makes the prediction of final fire size from conditions at the ignition difficult. We test this hypothesis by conducting a multi-scale statistical modelling of the factors determining whether fires reached 10 ha, then 100 ha then 1000 ha and the final size of fires >1000 ha. At each stage, the predictors were measures of weather, fuels, topography and fire suppression. The objectives were to identify differences among the models indicative of scale transitions, assess the accuracy of the multi-step method for predicting fire size (compared to predicting final size from initial conditions) and to quantify the importance of the predictors. The data were 1116 fires that occurred in the eucalypt forests of New South Wales between 1985 and 2010. The models were similar at the different scales, though there were subtle differences. For ex le, the presence of roads affected whether fires reached 10 ha but not larger scales. Weather was the most important predictor overall, though fuel load, topography and ease of suppression all showed effects. Overall, there was no evidence that fires have scale-dependent transitions in behaviour. The models had a predictive accuracy of 73%, 66%, 72% and 53% accuracy at 10 ha, 100 ha, 1000 ha and final size scales. When these steps were combined, the overall accuracy for predicting the size of fires was 62%, while the accuracy of the one step model was only 20%. Thus, the multi-scale approach was an improvement on the single scale approach, even though the predictive accuracy was probably insufficient for use as an operational tool. The analysis has also provided further evidence of the important role of weather, compared to fuel, suppression and topography in driving fire behaviour.

Effects of 38 years of wildfires on tree density in the Blue Mountains, Australia

Publisher: Wiley

Date: 21-09-2021

DOI: 10.1111/AEC.12952

Foraging ecology of the black flying fox (Pteropus alecto) in the seasonal tropics of the Northern Territory, Australia

Publisher: CSIRO Publishing

Date: 2000

DOI: 10.1071/WR97126

Abstract: Pteropus alecto uses landscape patchiness at two scales: firstly, between broad vegetation types (i.e. eucalypt open forest/savanna woodland versus rainforest vegetation) secondly, within vegetation types. Radio-collared Pteropus alecto selected foraging sites that were richer in flower or fruit resources than floristically similar sites and moved through the landscape in response to the flowering and fruiting of a number of plant species occurring in different vegetation types. Abundance of P. alecto within four monitored rainforest patches and the outside vegetation fluctuated substantially during the study. Overall, P. alecto was more abundant in the rainforests than in the surrounding vegetation. P. alecto foraged on the flowers and fruit from 23 species in 11 families.

HFE Genotype in Patients with Hemochromatosis and Other Liver Diseases

Publisher: American College of Physicians

Date: 15-06-1999

DOI: 10.7326/0003-4819-130-12-199906150-00002

Abstract: Hereditary hemochromatosis is a common inherited disorder of iron metabolism. The gene HFE, which contains two missense mutations (C282Y and H63D), was recently identified. To determine how HFE genotyping for the C282Y and H63D mutations contributes to the diagnosis of hemochromatosis and to determine the prevalence of HFE mutations in a group of patients with liver disease. Cross-sectional study. Academic medical center. 66 patients with hereditary hemochromatosis and 132 referred patients with other liver diseases. At initial diagnosis, fasting transferrin saturation, ferritin level, routine chemistry panel, and complete blood count were determined. Percutaneous liver biopsy was done on all patients for histologic analysis and measurement of hepatic iron concentration and hepatic iron index. HFE genotyping for the C282Y and H63D mutations was done on all patients by using genomic DNA s les. Of the 66 patients with hemochromatosis diagnosed on the basis of serum iron studies and liver biopsy findings, 60 (91%) were C282Y homozygotes, 2 (3%) were compound heterozygotes, 1 (1.5%) was a C282Y heterozygote, 2 (3%) were H63D heterozygotes, and 1 (1.5%) was negative for both mutations. Of the 132 patients with liver disease, 6 (5%) were C282Y homozygotes, 8 (6%) were compound heterozygotes, 6 (5%) were C282Y heterozygotes, 5 (4%) were H63D homozygotes, 20 (15%) were H63D heterozygotes, and 87 (66%) were negative for both mutations. All 66 C282Y homozygotes had an elevated hepatic iron concentration, and 65 of the 66 patients (98%) had a transferrin saturation of at least 45%. Ten of the 66 patients (15% [95% CI, 7.5% to 26%]) had a hepatic iron index less than 1.9 mmol/kg per year hemochromatosis was not suspected in 6 of the 10 patients before genotyping. Cirrhosis or substantial hepatic fibrosis was not seen in any (0% [CI, 0% to 18%]) of the 19 patients younger than 40 years of age who were homozygous for the C282Y mutation. All 66 patients homozygous for the C282Y mutation of HFE had an elevated hepatic iron concentration, but approximately 15% of these patients did not meet a previous diagnostic criterion for hemochromatosis (hepatic iron index > 1.9 mmol/kg per year). Determination of HFE genotype is clinically useful in patients with liver disease and suspected iron overload and may lead to identification of otherwise unsuspected C282Y homozygotes.

The potential for LiDAR technology to map fire fuel hazard over large areas of Australian forest

Publisher: Elsevier BV

Date: 10-2016

DOI: 10.1016/J.JENVMAN.2016.08.042

Abstract: Fuel load is a primary determinant of fire spread in Australian forests. In east Australian forests, litter and canopy fuel loads and hence fire hazard are thought to be highest at and beyond steady-state fuel loads 15-20 years post-fire. Current methods used to predict fuel loads often rely on course-scale vegetation maps and simple time-since-fire relationships which mask fine-scale processes influencing fuel loads. Here we use Light Detecting and Remote Sensing technology (LiDAR) and field surveys to quantify post-fire mid-story and crown canopy fuel accumulation and fire hazard in Dry Sclerophyll Forests of the Sydney Basin (Australia) at fine spatial-scales (20 × 20 m cell resolution). Fuel cover was quantified in three strata important for crown fire propagation (0.5-4 m, 4-15 m, >15 m) over a 144 km(2) area subject to varying fire fuel ages. Our results show that 1) LiDAR provided a precise measurement of fuel cover in each strata and a less precise but still useful predictor of surface fuels, 2) cover varied greatly within a mapped vegetation class of the same fuel age, particularly for elevated fuel, 3) time-since-fire was a poor predictor of fuel cover and crown fire hazard because fuel loads important for crown fire propagation were variable over a range of fire fuel ages between 2 and 38 years post-fire, and 4) fuel loads and fire hazard can be high in the years immediately following fire. Our results show the benefits of spatially and temporally specific in situ fuel s ling methods such as LiDAR, and are widely applicable for fire management actions which aim to decrease human and environmental losses due to wildfire.

Modelling surface fine fuel dynamics across climate gradients in eucalypt forests of south-eastern Australia

Publisher: Wiley

Date: 24-02-2014

DOI: 10.1111/ECOG.00445

Determining Fire Dates and Locating Ignition Points With Satellite Data

Publisher: MDPI AG

Date: 13-04-2016

DOI: 10.3390/RS8040326

The efficacy of fuel treatment in mitigating property loss during wildfires: Insights from analysis of the severity of the catastrophic fires in 2009 in Victoria, Australia

Publisher: Elsevier BV

Date: 12-2012

DOI: 10.1016/J.JENVMAN.2012.08.041

Abstract: Treatment of fuel (e.g. prescribed fire, logging) in fire-prone ecosystems is done to reduce risks to people and their property but effects require quantification, particularly under severe weather conditions when the destructive potential of fires on human infrastructure is maximised. We analysed the relative effects of fuel age (i.e. indicative of the effectiveness of prescribed fire) and logging on remotely sensed (SPOT imagery) severity of fires which occurred in eucalypt forests in Victoria, Australia in 2009. These fires burned under the most severe weather conditions recorded in Australia and caused large losses of life and property. Statistical models of the probability of contrasting extremes of severity (crown fire versus fire confined to the understorey) were developed based on effects of fuel age, logging, weather, topography and forest type. Weather was the primary influence on severity, though it was reduced at low fuel ages in Moderate but not Catastrophic, Very High or Low fire-weather conditions. Probability of crown fires was higher in recently logged areas than in areas logged decades before, indicating likely ineffectiveness as a fuel treatment. The results suggest that recently burnt areas (up to 5-10 years) may reduce the intensity of the fire but not sufficiently to increase the chance of effective suppression under severe weather conditions. Since house loss was most likely under these conditions (67%), effects of prescribed burning across landscapes on house loss are likely to be small when weather conditions are severe. Fuel treatments need to be located close to houses in order to effectively mitigate risk of loss.

Particulate Levels Underneath Landscape Fire Smoke Plumes in the Sydney Region of Australia

Publisher: MDPI AG

Date: 24-02-2023

DOI: 10.3390/FIRE6030086

Abstract: Smoke pollution from landscape fires is a major health problem, but it is difficult to predict the impact of any particular fire. For ex le, smoke plumes can be mapped using remote sensing, but we do not know how the smoke is distributed in the air-column. Prescribed burning involves the deliberate introduction of smoke to human communities but the amount, composition, and distribution of the pollution may be different to wildfires. We examined whether mapped plumes produced high levels of particulate pollution (PM2.5) at permanent air quality monitors and factors that influenced those levels. We mapped 1237 plumes, all those observed in 17 years of MODIS imagery over New South Wales, Australia, but this was only ~20% of known fires. Prescribed burn plumes tended to occur over more populated areas than wildfires. Only 18% of wildfire plumes and 4% of prescribed burn plumes passed over a monitor (n = 115). A minority of plumes caused a detectable increase in PM2.5: prescribed burn plumes caused an air quality exceedance for 33% of observations in the daytime and 11% at night, wildfire plumes caused exceedances for 48% and 22% of observations in the day and night-time, respectively. Thus, most plumes remained aloft (did not reach the surface). Statistical modelling revealed that wind speed, temperature, and mixing height influenced whether a plume caused an exceedance, and there was a difference between prescribed and wild fires. In particular, in wind speeds below 1 kmhr−1, exceedance was almost certain in prescribed burns. This information will be useful for planning prescribed burning, preparing warnings, and improving our ability to predict smoke impacts.

Environmental values and fire hazard of eucalypt plantings

Publisher: Wiley

Date: 11-2016

DOI: 10.1002/ECS2.1528

Local and regional smoke impacts from prescribed fires

Publisher: Copernicus GmbH

Date: 14-10-2016

DOI: 10.5194/NHESS-16-2247-2016

Abstract: Abstract. Smoke from wildfires poses a significant threat to affected communities. Prescribed burning is conducted to reduce the extent and potential damage of wildfires, but produces its own smoke threat. Planners of prescribed fires model the likely dispersion of smoke to help manage the impacts on local communities. Significant uncertainty remains about the actual smoke impact from prescribed fires, especially near the fire, and the accuracy of smoke dispersal models. To address this uncertainty, a detailed study of smoke dispersal was conducted for one small (52 ha) and one large (700 ha) prescribed fire near Appin in New South Wales, Australia, through the use of stationary and handheld pollution monitors, visual observations and rain radar data, and by comparing observations to predictions from an atmospheric dispersion model. The 52 ha fire produced a smoke plume about 800 m high and 9 km long. Particle concentrations (PM2.5) reached very high peak values ( 400 µg m−3) and high 24 h average values ( 100 µg m−3) at several locations next to or within ∼ 500 m downwind from the fire, but low levels elsewhere. The 700 ha fire produced a much larger plume, peaking at ∼ 2000 m altitude and affecting downwind areas up to 14 km away. Both peak and 24 h average PM2.5 values near the fire were lower than for the 52 ha fire, but this may be because the monitoring locations were further away from the fire. Some lofted smoke spread north against the ground-level wind direction. Smoke from this fire collapsed to the ground during the night at different times in different locations. Although it is hard to attribute particle concentrations definitively to smoke, it seems that the collapsed plume affected a huge area including the towns of Wollongong, Bargo, Oakdale, Camden and C belltown (∼ 1200 km2). PM2.5 concentrations up to 169 µg m−3 were recorded on the morning following the fire. The atmospheric dispersion model accurately predicted the general behaviour of both plumes in the early phases of the fires, but was poor at predicting fine-scale variation in particulate concentrations (e.g. places 500 m from the fire). The correlation between predicted and observed varied between 0 and 0.87 depending on location. The model also completely failed to predict the night-time collapse of the plume from the 700 ha fire. This study provides a preliminary insight into the potential for large impacts from prescribed fire smoke to NSW communities and the need for increased accuracy in smoke dispersion modelling. More research is needed to better understand when and why such impacts might occur and provide better predictions of pollution risk.

The impact of antecedent fire area on burned area in southern California coastal ecosystems

Publisher: Elsevier BV

Date: 12-2012

DOI: 10.1016/J.JENVMAN.2012.08.042

Abstract: Frequent wildfire disasters in southern California highlight the need for risk reduction strategies for the region, of which fuel reduction via prescribed burning is one option. However, there is no consensus about the effectiveness of prescribed fire in reducing the area of wildfire. Here, we use 29 years of historical fire mapping to quantify the relationship between annual wildfire area and antecedent fire area in predominantly shrub and grassland fuels in seven southern California counties, controlling for annual variation in weather patterns. This method has been used elsewhere to measure leverage: the reduction in wildfire area resulting from one unit of prescribed fire treatment. We found little evidence for a leverage effect (leverage = zero). Specifically our results showed no evidence that wildfire area was negatively influenced by previous fires, and only weak relationships with weather variables rainfall and Santa Ana wind occurrences, which were variables included to control for inter-annual variation. We conclude that this is because only 2% of the vegetation burns each year and so wildfires rarely encounter burned patches and chaparral shrublands can carry a fire within 1 or 2 years after previous fire. Prescribed burning is unlikely to have much influence on fire regimes in this area, though targeted treatment at the urban interface may be effective at providing defensible space for protecting assets. These results fit an emerging global model of fire leverage which position California at the bottom end of a continuum, with tropical savannas at the top (leverage = 1: direct replacement of wildfire by prescribed fire) and Australian eucalypt forests in the middle (leverage ~ 0.25).

ECOLOGICAL IMPLICATIONS OF FINE-SCALE FIRE PATCHINESS AND SEVERITY IN TROPICAL SAVANNAS OF NORTHERN AUSTRALIA

Publisher: Springer Science and Business Media LLC

Date: 04-2015

DOI: 10.4996/FIREECOLOGY.1101010

Abstract: Understanding fine-scale fire patchiness has significant implications for ecological processes and bio ersity conservation. It can affect local extinction of and recolonisation by relatively immobile fauna and poorly seed-dispersed flora in fire-affected areas. This study assesses fine-scale fire patchiness and severity, and associated implications for bio ersity, in north Australian tropical savanna systems. We used line transects to s le burning patterns of ground layer vegetation in different seasons and vegetation structure types, within the perimeter of 35 fires that occurred between 2009 and 2011. We evaluated two main fire characteristics: patchiness (patch density and mean patch length) and severity (inferred from char and scorch heights, and char and ash proportions). The mean burned area of ground vegetation was 83 % in the early dry season (EDS: May to July) and 93 % in the late dry season (LDS: August to November). LDS fires were less patchy (smaller and fewer unburned patches), and had higher fire severity (higher mean char and scorch heights, and twice the proportion of ash) than EDS fires. Fire patchiness varied among vegetation types, declining under more open canopy structure. The relationship between burned area and fire severity depended on season, being strongly correlated in the EDS and uncorrelated in the LDS. Simulations performed to understand the implications of patchiness on the population dynamics of fire-interval sensitive plant species showed that small amounts of patchiness substantially enhance survival. Our results indicate that the ecological impacts of high frequency fires on fire-sensitive regional bio ersity elements are likely to be lower than has been predicted from remotely sensed studies that are based on assumptions of homogeneous burning.

Spatial patterns of wildfire ignitions in south-eastern Australia

Publisher: CSIRO Publishing

Date: 2015

DOI: 10.1071/WF15054

Abstract: Wildfires can have devastating effects on life, property and the environment. Official inquiries following major damaging fires often recommend management actions to reduce the risk of future losses from wildfires. Understanding where wildfires are most likely to occur in the landscape is essential to determining where wildfires pose the greatest risk to people and property. We investigated the spatial patterns of wildfire ignitions at a bioregional scale in New South Wales and Victoria using generalised linear models. We used a combination of social and biophysical variables and examined whether different categories of ignitions respond to different explanatory variables. Human-caused ignitions are the dominant source of ignitions for wildfires in south-eastern Australia and our results showed that for such ignitions, population density was the most important variable for the spatial pattern of ignitions. In future years, more ignitions are predicted in the coastal and hinterland areas due to population increases and climate change effects.

An empirical wildfire risk analysis: the probability of a fire spreading to the urban interface in Sydney, Australia

Publisher: CSIRO Publishing

Date: 2015

DOI: 10.1071/WF14160

Abstract: We present a method and case study to predict and map the likelihood of wildfires spreading to the urban interface through statistical analysis of past fire patterns using 15 000 lines from 677 fires with known ignition points and date and random potential end points on the urban interface of Sydney, Australia. A binomial regression approach was used to model whether the fire burnt to the end point of the lines as a function of measures of distance, fuel, weather and barriers to spread. Fire weather had the strongest influence on burning likelihood followed by the percentage of the line that was forested, distance and time since last fire. Fuel treatments would substantially reduce risk from fires starting 1–4 km away from the interface. The model captured 90% of variation in burning with 98% predictive accuracy on test data and was not affected by spatial autocorrelation. We apply the method to map fire risk in Sydney and discuss how the method could be expanded to estimate total risk (from ignition to impact on assets). The method has considerable promise for predicting risk, especially as a complement to simulation methods.

The spatial domain of wildfire risk and response in the wildland urban interface in Sydney, Australia

Publisher: Copernicus GmbH

Date: 23-12-2013

DOI: 10.5194/NHESS-13-3385-2013

Abstract: Abstract. In order to quantify the risks from fire at the wildland urban interface (WUI), it is important to understand where fires occur and their likelihood of spreading to the WUI. For each of the 999 fires in the Sydney region we calculated the distance between the ignition and the WUI, the fire's weather and wind direction and whether it spread to the WUI. The likelihood of burning the WUI was analysed using binomial regression. Weather and distance interacted such that under mild weather conditions, the model predicted only a 5% chance that a fire starting .5 km from the interface would reach it, whereas when the conditions are extreme the predicted chance remained above 30% even at distances km. Fires were more likely to spread to the WUI if the wind was from the west and in the western side of the region. We examined whether the management responses to wildfires are commensurate with risk by comparing the distribution of distance to the WUI of wildfires with roads and prescribed fires. Prescribed fires and roads were concentrated nearer to the WUI than wildfires as a whole, but further away than wildfires that burnt the WUI under extreme weather conditions (high risk fires). Overall, 79% of these high risk fires started within 2 km of the WUI, so there is some argument for concentrating more management effort near the WUI. By substituting climate change scenario weather into the statistical model, we predicted a small increase in the risk of fires spreading to the WUI, but the increase will be greater under extreme weather. This approach has a variety of uses, including mapping fire risk and improving the ability to match fire management responses to the threat from each fire. They also provide a baseline from which a cost-benefit analysis of complementary fire management strategies can be conducted.

The role of weather, past fire and topography in crown fire occurrence in eastern Australia

Publisher: CSIRO Publishing

Date: 2016

DOI: 10.1071/WF15171

Abstract: We analysed the influence of weather, time since fire (TSF) and topography on the occurrence of crown fire, as mapped from satellite imagery, in 23 of the largest wildfires in dry sclerophyll forests in eastern Australia from 2002 to 2013. Fires were analysed both in idually and as groups. Fire weather was the most important predictor of crown consumption. TSF (a surrogate for fuel accumulation) had complex nonlinear effects that varied among fires. Crown fire likelihood was low up to 4 years post-fire, peaked at ~10 years post-fire and then declined. There was no clear indication that recent burning became more or less effective as fire weather became more severe. Steeper slope reduced crown fire likelihood, contrary to the assumptions of common fire behaviour equations. More exposed areas (ridges and plains) had higher crown fire likelihood. Our results suggest prescribed burning to maintain an average of 10 years’ TSF may actually increase crown fire likelihood, but burning much more frequently can be effective for risk reduction. Our results also suggest the effects of weather, TSF and slope are not adequately represented in the underlying equations of most fire behaviour models, potentially leading to poor prediction of fire spread and risk.

The role of construction standards on building impact of the 2013 Linksview Wildfire, Australia

Publisher: Elsevier BV

Date: 03-2022

DOI: 10.1016/J.FIRESAF.2022.103545

The terrestrial vertebrate fauna of Litchfield National Park, Northern Territory: monitoring over a 6-year period and response to fire history

Publisher: CSIRO Publishing

Date: 2004

DOI: 10.1071/WR03077

Abstract: Forty-seven 50 m × 50 m quadrats were s led systematically for vertebrates at Litchfield National Park, northern Australia, in both 1995–96 and 2001–02. A total of 184 vertebrate species was recorded from this s ling, of which 92 species were recorded from five or more quadrats. There was substantial change in the reported species composition of these quadrats between these two periods: the mean Bray–Curtis index for similarity in species composition from the baseline to subsequent s ling of a quadrat was only 22.1 (for an index that varies from 0 for complete turnover in species to 100 for unchanged composition). For in idual species, correlations across quadrats in the abundance scores from baseline to res ling varied from –0.12 to 0.85. Matched-pairs testing showed that there was significant change in abundance for 18 species from the baseline to repeat s ling, and significant increase in total bird species richness and total native mammal abundance, but significant decrease in reptile species richness. Fire history was recorded biannually for 40 of the 47 quadrats. Fire was very frequent, with quadrats being burnt in an average of 3.65 years of the six years between fauna s les. Three aspects of this fire history (total number of years of fires, number of fires in the late dry season, and interval from the last fire to the date of res ling) were related to change in the fauna composition of quadrats. Neither the similarity in species composition, nor change in richness or total abundance of all vertebrates or of the four taxonomic classes considered (frogs, reptiles, birds and mammals) were significantly correlated with these components of the fire history of s led quadrats. This lack of association was possibly because the monitoring period was too short to show pronounced directional change, because the system was responding to many factors other than fire, because the variations in abundance were too large and the number of s les too small to detect true associations, or because fire histories preceding baseline s ling were not considered. The apparent instability of fauna species and communities in this system provides a considerable challenge for broad-brush (that is, vertebrate community–wide) monitoring. Power analysis demonstrated that, for most species, more than 1000 s le sites are needed to be 90% certain of detecting a 20% change in abundance, and with a 10% chance of accepting a Type I error. This level of s ling effort is commensurate with the current level of vertebrate s ling in this region. Broad-brush monitoring approaches such as described here are valuable, but need also to be complemented by more targetted monitoring for in idual threatened species or species of particular management interest.

Modelling the determinants of ignition in the Sydney Basin, Australia: implications for future management

Publisher: CSIRO Publishing

Date: 2013

DOI: 10.1071/WF12027

Abstract: Variations in area burnt by fire are governed by four processes: biomass growth, availability to burn, fire weather and ignitions. Insight into these how these processes are shaped by biophysical and human influences is required to underpin the development of effective management strategies. Patterns of natural and arson ignitions were examined within the densely populated Sydney region of south-eastern Australia to determine the extent to which management can alter the risk of ignition. Arson ignitions were more likely on ridges in association with human infrastructure, i.e. roads and houses. Lightning ignitions also occurred more frequently on ridges, but at greater distances from human infrastructure. These patterns are consistent with those reported in studies from forested regions in the northern hemisphere. Fuel age had a variable effect with lightning more likely in older fuels ( years) and arson more likely in younger fuels ( years). Probability of both ignition types increased under more severe fire weather. Climate change is predicted to increase the severity of fire weather and is therefore likely to result in an increase in ignition frequency in the Sydney Basin. Urban expansion is also likely to have significant effects on ignitions and resultant risks to people and property via an increase in the probability of arson ignitions.

Movements of frugivorous birds among fragmented rainforests in the Northern Territory, Australia

Publisher: CSIRO Publishing

Date: 2006

DOI: 10.1071/WR06029

Abstract: Rainforests in the Northern Territory occur as small patches, and the frugivorous birds that depend on them are thought to move among the patches. I attached radio-transmitters to 41 birds of four species captured in several locations near Darwin. I recorded 55 interpatch flights, and estimated flight rates as between once per day and five days for figbirds and pied imperial-pigeons. The flight rates for rose-crowned fruit-doves and yellow orioles were much lower, but no reliable estimate could be made. The median flight distance was 2.5 km but one in five flights were more than 10 km. In addition, one pigeon flew 220 km in preparation for migration from Australia. Birds often undertook exploratory flights, returning to the original patch. Birds of one species captured together usually flew to different locations. When birds left a patch, it was usually to a distant patch, rather than a near neighbour. These movement patterns demonstrate that frugivorous birds use the rainforest network in a complex way. The birds depend on a network of rainforest patches and the pigeons and figbirds probably disperse large quantities of seeds among the patches. The conservation of rainforest ecosystems in northern Australia will depend on the protection of the current configuration of patches rather than a representative set of patches.

Application of a taxon priority system for conservation planning by selecting areas which are most distinct from environments already reserved

Publisher: Elsevier BV

Date: 1996

DOI: 10.1016/0006-3207(95)00106-9

Tree hollows and forest stand structure in Australian warm temperate Eucalyptus forests are adversely affected by logging more than wildfire

Publisher: Elsevier BV

Date: 04-2015

DOI: 10.1016/J.FORECO.2014.12.023

Multi-Factor Analysis of House Loss in Two Major Wildfire Seasons in NSW Australia

Publisher: MDPI

Date: 16-09-2022

DOI: 10.3390/ENVIRONSCIPROC2022017128

Changing Weather Extremes Call for Early Warning of Potential for Catastrophic Fire

Publisher: American Geophysical Union (AGU)

Date: 12-2017

DOI: 10.1002/2017EF000657

Forest fire management, climate change, and the risk of catastrophic carbon losses

Publisher: Wiley

Date: 03-2013

DOI: 10.1890/13.WB.005

How do weather and terrain contribute to firefighter entrapments in Australia?

Publisher: CSIRO Publishing

Date: 2018

DOI: 10.1071/WF17114

Abstract: Adverse weather conditions and topographic influences are suspected to be responsible for most entrapments of firefighters in Australia. A lack of temporally and spatially coherent set of data however, hinders a clear understanding of the contribution of each weather type or terrain driver on these events. We investigate coronial inquiries and internal fire agencies reports across several Australian states from 1980 to 2017 and retrieve 45 entrapments. A first analysis reveals that most entrapments happen during large fires and that the number of deaths has decreased over the last few decades. Comparing the meteorological and topographical conditions of the entrapments with the conditions of a reference set of fires without entrapment, we build a linear regression model that identifies the main contributors to firefighter entrapment. A change in wind direction, which was associated with 42% of the incidents examined, is the main factor contributing to entrapments. Interaction between strong winds and steep slopes also influences the likelihood of entrapment and suggests that dynamic fire behaviours may also play important roles. As further details of this relationship between dynamic fire propagation and firefighter entrapment is now required, the understanding of weather and terrain contribution is a first step to produce comprehensive safety guidance.

Indirect evidence that frugivorous birds track fluctuating fruit resources among rainforest patches in the Northern Territory, Australia

Publisher: Wiley

Date: 04-2004

DOI: 10.1111/J.1442-9993.2004.01331.X

Potential role of ignition management in reducing unplanned burning in Arnhem Land, Australia

Publisher: Wiley

Date: 05-2015

DOI: 10.1111/AEC.12264

Monitoring the impacts of fire regimes on vegetation in northern Australia: an example from Kakadu National Park

Publisher: CSIRO Publishing

Date: 2003

DOI: 10.1071/WF03031

Abstract: We describe the rationale, methodology and preliminary results from a major monitoring program in Kakadu National Park, northern Australia. The program aims to assess fire regimes, their impacts upon bio ersity, and the consequences and efficacy of fire management. The program comprises two complementary elements—mapping of fire histories based upon interpretation of satellite imagery, and assessment of vegetation at a large series of permanent monitoring plots. The program commenced formally in 1995, at which time establishment and baseline s ling of vegetation in 134 plots was conducted, with re-s ling proposed at 5-year intervals up to 2010. The monitoring program has an estimated annual cost of about $A140�000 (around 1% of the total annual budget of the Park). Over the period 1995–2000, the mean annual extent of burning was 40.3%, a marginal reduction in extent from the previous 15 years, particularly for late dry season fires in lowland habitats. From the baseline (1995) and subsequent re-s ling (2000) of the vegetation plots, 963 plant taxa have been recorded. The power of the program to detect change in the frequency or abundance of in idual species was poor, especially for ground-layer species, largely because of typically substantial variability in abundance across plots and s ling events, and because of the high proportion of species recorded from few s les. Notwithstanding this constraint, five tree species (of 47 recorded from sufficient s les to test), nine shrub species (from 121) and 27 ground-layer species (from 111) showed significant change in abundance between the baseline and subsequent s ling. However when species were grouped into strata and life-form categories, major changes were evident over this 5�year period, particularly with increases in cover of trees and shrubs. Such changes were related to a range of environmental and fire regime parameters of the plots, with increase in woody cover but reduction in cover and species richness of herbs in those plots experiencing lower frequency of fires.

Acacia shrubs respond positively to high severity wildfire: Implications for conservation and fuel hazard management

Publisher: Elsevier BV

Date: 2017

DOI: 10.1016/J.SCITOTENV.2016.09.129

Abstract: High severity wildfires pose threats to human assets, but are also perceived to impact vegetation communities because a small number of species may become dominant immediately after fire. However there are considerable gaps in our knowledge about species-specific responses of plants to different fire severities, and how this influences fuel hazard in the short and long-term. Here we conduct a floristic survey at sites before and two years after a wildfire of unprecedented size and severity in the Warrumbungle National Park (Australia) to explore relationships between post-fire growth of a fire responsive shrub genera (Acacia), total mid-story vegetation cover, fire severity and fuel hazard. We then survey 129 plots surrounding the park to assess relationships between mid-story vegetation cover and time-since-fire. Acacia species richness and cover were 2.3 and 4.3 times greater at plots after than before the fire. However the same common dominant species were present throughout the study. Mid-story vegetation cover was 1.5 times greater after than before the wildfire, and Acacia species contribution to mid-story cover increased from 10 to 40%. Acacia species richness was not affected by fire severity, however strong positive associations were observed between Acacia and total mid-story vegetation cover and severity. Our analysis of mid-story vegetation recovery showed that cover was similarly high between 2 and 30years post-fire, then decreased until 52years. Collectively, our results suggest that Acacia species are extremely resilient to high severity wildfire and drive short to mid-term increases in fuel hazard. Our results are discussed in relation to fire regime management from the twin perspectives of conserving bio ersity and mitigating human losses due to wildfire.

Effects of weather, fuel and terrain on fire severity in topographically diverse landscapes of south-eastern Australia

Publisher: Springer Science and Business Media LLC

Date: 25-12-2010

DOI: 10.1007/S10980-009-9443-8

Examining the relative effects of fire weather, suppression and fuel treatment on fire behaviour - A simulation study

Publisher: Elsevier BV

Date: 12-2013

DOI: 10.1016/J.JENVMAN.2013.10.007

Abstract: Large budgets are spent on both suppression and fuel treatments in order to reduce the risk of wildfires. There is little evidence regarding the relative contribution of fire weather, suppression and fuel treatments in determining the risk posed from wildfires. Here we undertake a simulation study in the Sydney Basin, Australia, to examine this question using a fire behaviour model (Phoenix Rapidfire). Results of the study indicate that fire behaviour is most strongly influenced by fire weather. Suppression has a greater influence on whether a fire reaches 5 ha in size compared to fuel treatments. In contrast, fuel treatments have a stronger effect on the fire size and maximum distance the fire travels. The study suggests that fire management agencies will receive additional benefits from fuel treatment if they are located in areas which suppression resources can respond rapidly and attempt to contain the fires. No combination of treatments contained all fires, and the proportion of uncontained fires increased under more severe fire weather when the greatest number of properties are lost. Our study highlights the importance of alternative management strategies to reduce the risk of property loss.

Prescribed burning: how can it work to conserve the things we value?

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/WF09131

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 bio ersity 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.

A modeling study of the effect of gravity on airflow distribution and particle deposition in the lung

Publisher: Informa UK Limited

Date: 2006

DOI: 10.1080/08958370600602009

Abstract: Inhalation of particles generated as a result of thermal degradation from fire or smoke, as may occur on spacecraft, is of major health concern to space-faring countries. Knowledge of lung airflow and particle transport under different gravity environments is required to addresses this concern by providing information on particle deposition. Gravity affects deposition of particles in the lung in two ways. First, the airflow distribution among airways is changed in different gravity environments. Second, particle losses by sedimentation are enhanced with increasing gravity. In this study, a model of airflow distribution in the lung that accounts for the influence of gravity was used for a mathematical description of particle deposition in the human lung to calculate lobar, regional, and local deposition of particles in different gravity environments. The lung geometry used in the mathematical model contained five lobes that allowed the assessment of lobar ventilation distribution and variation of particle deposition. At zero gravity, it was predicted that all lobes of the lung expanded and contracted uniformly, independent of body position. Increased gravity in the upright position increased the expansion of the upper lobes and decreased expansion of the lower lobes. Despite a slight increase in predicted deposition of ultrafine particles in the upper lobes with decreasing gravity, deposition of ultrafine particles was generally predicted to be unaffected by gravity. Increased gravity increased predicted deposition of fine and coarse particles in the tracheobronchial region, but that led to a reduction or even elimination of deposition in the alveolar region for coarse particles. The results from this study show that existing mathematical models of particle deposition at 1 G can be extended to different gravity environments by simply correcting for a gravity constant. Controlled studies in astronauts on future space missions are needed to validate these predictions.

Simplifying the savanna: the trajectory of fire-sensitive vegetation mosaics in northern Australia

Publisher: Wiley

Date: 09-02-2012

DOI: 10.1111/J.1365-2699.2012.02679.X

The effect of fuel age on the spread of fire in sclerophyll forest in the Sydney region of Australia

Publisher: CSIRO Publishing

Date: 2010

DOI: 10.1071/WF08167

Abstract: We investigated the effect of fuel age on the truncation of spread of unplanned fires using a set of 1473 patches in the Sydney region of Australia. Twenty-two percent of patches derived from prescribed fire experienced a subsequent unplanned fire within 5 years, compared with 42% of patches derived from unplanned fires. Among those encounters, the subsequent unplanned fire stopped at the leading edge of 18% of prescribed patches and 11% of unplanned patches. In comparison, the subsequent fire stopped somewhere in the patch for 44% of both prescribed and unplanned fires. Overall, there was a 10% chance that a prescribed burn patch would experience an unplanned fire that stops within the patch. Statistical modelling revealed that the presence of a road barrier was the best predictor of the likelihood of stopping on the leading edge, but fuel age and weather also had an influence. Stopping on the trailing edge was less influenced by the variables analysed. In extreme weather, even 1-year-old patches have a low likelihood of stopping unplanned fires. Fuel age had little influence on the spread of unplanned fires. Consequently, prescribed fires will be most effective when sited at the urban interface where resultant reduced unplanned fire intensity will be a benefit.

Reducing the risk of house loss due to wildfires

Publisher: Elsevier BV

Date: 05-2015

DOI: 10.1016/J.ENVSOFT.2014.12.020

University Of Tasmania

Location: Australia

View Organisation

University Of Tasmania

Location: No location found

View Organisation

University Of Wollongong

Location: Australia

View Organisation

Linkage Projects - Grant ID: LP0882048

Start Date: 04-2008

End Date: 12-2011

Amount: $440,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP0348543

Start Date: 10-2003

End Date: 06-2007

Amount: $395,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP220100358

Start Date: 09-2023

End Date: 09-2026

Amount: $540,183.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP130100146

Start Date: 04-2014

End Date: 12-2018

Amount: $559,330.00

Funder: Australian Research Council