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Unprecedented wildfires in south-eastern Australia in 2019-20 focused attention on forest management to reduce their risks and impacts. These fires mostly burnt dry eucalypt forests. In this short review, we found evidence from international studies that thinning combined with fuel reduction can reduce wildfire risks and impacts in dry forests compared to no treatment or thinning alone. In Australia studies so far demonstrate mixed outcomes, indicating that more landscape-scale experiments are required to better assess the use of thinning in dry Eucalyptus forests to reduce fire risks in a rapidly changing climate.
Rodney J. Keenan; Christopher J. Weston; Liubov Volkova. Potential for forest thinning to reduce risk and increase resilience to wildfire in Australian temperate Eucalyptus forests. Current Opinion in Environmental Science & Health 2021, 23, 100280 .
AMA StyleRodney J. Keenan, Christopher J. Weston, Liubov Volkova. Potential for forest thinning to reduce risk and increase resilience to wildfire in Australian temperate Eucalyptus forests. Current Opinion in Environmental Science & Health. 2021; 23 ():100280.
Chicago/Turabian StyleRodney J. Keenan; Christopher J. Weston; Liubov Volkova. 2021. "Potential for forest thinning to reduce risk and increase resilience to wildfire in Australian temperate Eucalyptus forests." Current Opinion in Environmental Science & Health 23, no. : 100280.
Prescribed fire to reduce forest fuels has been routinely applied to reduce wildfire risk in many parts of the world. It has also been proposed that prescribed fire can be used to mitigate greenhouse gas (GHG) emissions. Although prescribed fire creates emissions, if the treatment also decreases the incidence of subsequent wildfires, it is possible for the net outcome to be an emissions decline. Previous studies have suggested prescribed fire, at the frequencies required to materially impact wildfire occurrence, generally leads to net emissions increases. A focus on emissions means any change in carbon storage within the ecosystem remains unaccounted for; because living, dead, and soil carbon pools are characterized by different residence times, a re-distribution of carbon amongst these pools may either reduce or increase long-term ecosystem carbon stores. A full ecosystem carbon model has been developed to investigate the implications of prescribed fire management on total Net Ecosystem Carbon Balance (NECB), inclusive of both emissions and carbon storage. Consistent with previous work, the results suggested limited potential for reducing net GHG emissions through applying prescribed fire, with higher emissions from prescribed fire approximately offset by lower emissions and avoided carbon losses from the subsequent reduction in wildfire frequency. For example, shortening the prescribed fire interval from 25 to 10 years resulted in a NECB sequestration that was typically less than ±0.4 Mg C ha−1 yr−1, or less than approximately 0.1% of the total ecosystem carbon storage. Hence, whilst there was limited opportunity for achieving emission abatement outcomes from changing prescribed fire management, there were no significant emission penalties for doing so. These results suggest land managers should be free to adopt prescribed fire regimes to target specific management outcomes, without significantly impacting net emissions or total ecosystem carbon storage over the long term.
Liubov Volkova; Stephen H. Roxburgh; Christopher J. Weston. Effects of prescribed fire frequency on wildfire emissions and carbon sequestration in a fire adapted ecosystem using a comprehensive carbon model. Journal of Environmental Management 2021, 290, 112673 .
AMA StyleLiubov Volkova, Stephen H. Roxburgh, Christopher J. Weston. Effects of prescribed fire frequency on wildfire emissions and carbon sequestration in a fire adapted ecosystem using a comprehensive carbon model. Journal of Environmental Management. 2021; 290 ():112673.
Chicago/Turabian StyleLiubov Volkova; Stephen H. Roxburgh; Christopher J. Weston. 2021. "Effects of prescribed fire frequency on wildfire emissions and carbon sequestration in a fire adapted ecosystem using a comprehensive carbon model." Journal of Environmental Management 290, no. : 112673.
This study assessed the accuracy of land cover change (2000–2018) maps compiled from Landsat images with either automated digital processing or with visual interpretation for a tropical forest area in Indonesia. The accuracy assessment used a two-stage stratified random sampling involving a confusion matrix for assessing map accuracy and by estimating areas of land cover change classes and associated uncertainty. The reference data were high-resolution images from SPOT 6/7 and high-resolution images finer than 5 m obtained from Open Foris Collect Earth. Results showed that the map derived from automated digital processing had lower accuracy (overall accuracy 73–77%) compared to the map based on visual interpretation (overall accuracy 80–84%). The automated digital processing map error was in differentiating between native forest and plantation areas. While the visual interpretation map had a higher accuracy, it did not consistently differentiate between native forest and shrub areas. Future improvement of the digital map requires more accurate differentiation between forest and plantation to better support national forest monitoring systems for sustainable forest management.
Inggit Sari; Christopher Weston; Glenn Newnham; Liubov Volkova. Assessing Accuracy of Land Cover Change Maps Derived from Automated Digital Processing and Visual Interpretation in Tropical Forests in Indonesia. Remote Sensing 2021, 13, 1446 .
AMA StyleInggit Sari, Christopher Weston, Glenn Newnham, Liubov Volkova. Assessing Accuracy of Land Cover Change Maps Derived from Automated Digital Processing and Visual Interpretation in Tropical Forests in Indonesia. Remote Sensing. 2021; 13 (8):1446.
Chicago/Turabian StyleInggit Sari; Christopher Weston; Glenn Newnham; Liubov Volkova. 2021. "Assessing Accuracy of Land Cover Change Maps Derived from Automated Digital Processing and Visual Interpretation in Tropical Forests in Indonesia." Remote Sensing 13, no. 8: 1446.
Two systems of additive equations were developed to predict aboveground stand level biomass in log products and harvest residue from routinely measured or predicted stand variables for Pinus radiata plantations in New South Wales, Australia. These plantations were managed under three thinning regimes or stand types before clear-felling at rotation age by cut-to-length harvesters to produce sawlogs and pulpwood. The residue material following a clear-fell operation mainly consisted of stumps, branches and treetops, short off-cut and waste sections due to stem deformity, defects, damage and breakage. One system of equations did not include dummy variables for stand types in the model specification and was intended for more general use in plantations where stand density management regimes were not the same as the stand types in our study. The other system that incorporated dummy variables was for stand type-specific applications. Both systems of equations were estimated using 61 plot-based estimates of biomass in commercial logs and residue components that were derived from systems of equations developed in situ for predicting the product and residue biomass of individual trees. To cater for all practical applications, two sets of parameters were estimated for each system of equations for predicting component and total aboveground stand biomass in fresh and dry weight respectively. The two sets of parameters for the system of equations without dummy variables were jointly estimated to improve statistical efficiency in parameter estimation. The predictive performances of the two systems of equations were benchmarked through a leave-one-plot-out cross validation procedure. They were generally superior to the performance of an alternative two-stage approach that combined an additive system for major components with an allocative system for sub-components. As using forest harvest residue biomass for bioenergy has increasingly become an integrated part of forestry, reliable estimates of product and residue biomass will assist harvest and management planning for clear-fell operations that integrate cut-to-length log production with residue harvesting.
Xixi Qiao; Huiquan Bi; Yun Li; Fabiano Ximenes; Christopher J. Weston; Liubov Volkova; Mohammad Reza Ghaffariyan. Additive predictions of aboveground stand biomass in commercial logs and harvest residues for rotation age Pinus radiata plantations in New South Wales, Australia. Journal of Forestry Research 2021, 1 -25.
AMA StyleXixi Qiao, Huiquan Bi, Yun Li, Fabiano Ximenes, Christopher J. Weston, Liubov Volkova, Mohammad Reza Ghaffariyan. Additive predictions of aboveground stand biomass in commercial logs and harvest residues for rotation age Pinus radiata plantations in New South Wales, Australia. Journal of Forestry Research. 2021; ():1-25.
Chicago/Turabian StyleXixi Qiao; Huiquan Bi; Yun Li; Fabiano Ximenes; Christopher J. Weston; Liubov Volkova; Mohammad Reza Ghaffariyan. 2021. "Additive predictions of aboveground stand biomass in commercial logs and harvest residues for rotation age Pinus radiata plantations in New South Wales, Australia." Journal of Forestry Research , no. : 1-25.
(1) Research Highlights: Thermal damage to cambium cells of Eucalyptus held in vitro was recorded at sublethal temperatures (40 °C–50 °C) when the duration of exposure extends beyond 2.5 min up to 5 min. (2) Background and Objectives: During a forest fire, heat can be transferred through tree bark potentially impacting viability of vascular cambium cells and the perennial growth of the tree. With the increased temperature of the cambium, cells are known to lose viability at temperatures exceeding 60 °C. However, it is possible that extended exposure to temperatures below 60 °C may also impair cell viability. This study aimed to identify the effect of the temperature and exposure time interaction on the cambium cell viability of Eucalyptus, a genus widely distributed in natural forests and commercial plantations globally. (3) Methods: Excised cambium-phloem tissue sections from three Eucalyptus species (Messmate–E. obliqua L’Hér., Narrow-leaf peppermint–E. radiata Sieber ex DC. and Swamp gum–E. ovata Labill.) were exposed in vitro to a series of temperature–time treatments (40 °C, 50 °C, 60 °C, 70 °C for 1 min, 2.5 min, and 5 min) and tested for cell viability using a tetrazolium reduction method. (4) Results: Cell viability of cambium cells decreased with increased temperature and exposure times for all three Eucalyptus species. Longer exposure to sublethal temperatures of 40 °C to 50 °C showed statistically similar results to shorter exposure to lethal temperatures (>50 °C). (5) Conclusions: Longer exposure to sublethal temperatures (40 °C–50 °C) caused irreversible thermal damage to cambium cells of Eucalyptus when tested in vitro, further refining our understanding of raised temperature on cell viability.
Yasika Subasinghe Achchige; Liubov Volkova; Christopher Weston. Effect of Temperature and Exposure Time on Cambium Cell Viability In Vitro for Eucalyptus Species. Forests 2021, 12, 445 .
AMA StyleYasika Subasinghe Achchige, Liubov Volkova, Christopher Weston. Effect of Temperature and Exposure Time on Cambium Cell Viability In Vitro for Eucalyptus Species. Forests. 2021; 12 (4):445.
Chicago/Turabian StyleYasika Subasinghe Achchige; Liubov Volkova; Christopher Weston. 2021. "Effect of Temperature and Exposure Time on Cambium Cell Viability In Vitro for Eucalyptus Species." Forests 12, no. 4: 445.
Accurate assessment of tropical peat forest carbon stocks and impact of fires on carbon pools is required to determine the magnitude of emissions to the atmosphere and to support emissions reduction policies. We assessed total aboveground carbon (AGC) in biomass pools including trees, shrubs, deadwood, litter and char, and peat carbon to develop empirical estimates of peat swamp forest carbon stocks in response to fire and disturbance. In contrast to the common assumption that peat fires combust all AGC, we observed that about half of undisturbed forest AGC, equivalent to about 70 Mg C ha−1, remains after one or two recent fires – mainly in dead trees, woody debris and pyrogenic carbon. Both recently burnt and repeatedly burnt peat forests store similar amounts of carbon in the top 10 cm of peat when compared with undisturbed forests (70 Mg C ha−1), mainly due to increased peat bulk density after fires that compensates for their lower peat C%. The proportion of fuel mass consumed in fire, or combustion factor (CF), is required to make accurate estimates of peat fire emissions for both AGC and peat carbon. This study estimated a CF for AGC (CFAGC) of 0.56, comparable to the default value of the Intergovernmental Panel on Climate Change (IPCC). This study estimated a varying CF for peat (CFPEAT) that ranged from 0.4 to 0.68 as depth of burn increased. This revised CFPEAT is one third to one half of the IPCC default value of 1.0. The current assumption of complete combustion of peat (CF = 1.0) is widely acknowledged in the literature as oversimplification and is not supported by our field observations or data. This study provides novel empirical data to improve estimates of peat forests carbon stocks and emissions from tropical peat fires.
Haruni Krisnawati; Wahyu C. Adinugroho; Rinaldi Imanuddin; Suyoko; Christopher J. Weston; Liubov Volkova. Carbon balance of tropical peat forests at different fire history and implications for carbon emissions. Science of The Total Environment 2021, 779, 146365 .
AMA StyleHaruni Krisnawati, Wahyu C. Adinugroho, Rinaldi Imanuddin, Suyoko, Christopher J. Weston, Liubov Volkova. Carbon balance of tropical peat forests at different fire history and implications for carbon emissions. Science of The Total Environment. 2021; 779 ():146365.
Chicago/Turabian StyleHaruni Krisnawati; Wahyu C. Adinugroho; Rinaldi Imanuddin; Suyoko; Christopher J. Weston; Liubov Volkova. 2021. "Carbon balance of tropical peat forests at different fire history and implications for carbon emissions." Science of The Total Environment 779, no. : 146365.
Tropical peatlands are areas of high carbon density that are important in biosphere-atmosphere interactions. Drainage and burning of tropical peatlands releases about 5% of global greenhouse gas (GHG) emissions, yet there is great uncertainty in these estimates. Our comprehensive literature review of parameters required to calculate GHG emissions from burnt peat forests, following the international guidelines, revealed many gaps in knowledge of carbon pools and few recent supporting studies. To improve future estimates of the total ecosystem carbon balance and peatfire emissions this study aimed to account for all carbon pools: aboveground, deadwood, pyrogenic carbon (PyC) and peat of single and repeatedly burnt peat forests. A further aim was to identify the minimum sampling intensity required to detect with 80% power significant differences in these carbon pools among long unburnt, recently burnt and repeatedly burnt peat swamp forests. About 90 Mg C ha−1 remains aboveground as deadwood after a single fire and half of this remains after a second fire. One fire produces 4.5 ± 0.6 Mg C ha−1 of PyC, with a second fire increasing this to 7.1 ± 0.8 Mg C ha−1. For peat swamp forests these aboveground carbon pools are rarely accounted in estimates of emissions following multiple fires, while PyC has not been included in the total peat carbon mass balance. Peat bulk density and peat carbon content change with fire frequency, yet these parameters often remain constant in the published emission estimates following a single and multiple fires. Our power analysis indicated that as few as 12 plots are required to detect meaningful differences between fire treatments for the major carbon pools. Further field studies directed at improving the parameters for calculating carbon balance of disturbed peat forest ecosystems are required to better constrain peatfire GHG emission estimates.
Liubov Volkova; Haruni Krisnawati; Wahyu C. Adinugroho; Rinaldi Imanuddin; Muhammad A. Qirom; Purwanto B. Santosa; Wawan Halwany; Christopher J. Weston. Identifying and addressing knowledge gaps for improving greenhouse gas emissions estimates from tropical peat forest fires. Science of The Total Environment 2020, 763, 142933 .
AMA StyleLiubov Volkova, Haruni Krisnawati, Wahyu C. Adinugroho, Rinaldi Imanuddin, Muhammad A. Qirom, Purwanto B. Santosa, Wawan Halwany, Christopher J. Weston. Identifying and addressing knowledge gaps for improving greenhouse gas emissions estimates from tropical peat forest fires. Science of The Total Environment. 2020; 763 ():142933.
Chicago/Turabian StyleLiubov Volkova; Haruni Krisnawati; Wahyu C. Adinugroho; Rinaldi Imanuddin; Muhammad A. Qirom; Purwanto B. Santosa; Wawan Halwany; Christopher J. Weston. 2020. "Identifying and addressing knowledge gaps for improving greenhouse gas emissions estimates from tropical peat forest fires." Science of The Total Environment 763, no. : 142933.
More frequent hot and windy weather in fire prone forested landscapes requires that a full suite of fuel reduction measures be investigated for effectiveness in fuel hazard reduction, environmental impact and carbon (C) outcomes. Although prescribed fire and thinning are routinely applied in forests of North America to reduce fuel loads, there are few detailed studies from Australia. We report the impacts of fuel reduction treatments including burning, mechanical thinning and the combination of both on forest C and fuel hazard in open forests dominated by Eucalyptus sieberi in south-eastern Australia. Carbon losses to the atmosphere and redistribution within the forest were calculated from stocks within each fuel category before and after treatment. Mechanical thinning + burning was the most effective treatment for reducing aboveground C and fuel hazard, with major reductions in dead trees, stumps and understorey, as well as stems removed for sale as pulpwood. However forest floor fuel loads increased in thinned treatments relative to control forests. The overall fuel hazard rating in the burn only treatment was significantly reduced from extreme to low immediately following burning. In thinned only stands, the overall fuel hazard rating did not change from the pre-treatment rating of extreme, due to high surface and forest floor fuel loads and loose and flammable bark on the retained overstorey trees. This result suggests the current fuel hazard guide in use in Australia should be revised to enable it to better describe the benefits of thinning for fuel reduction - in this case the removal of about 50% of aboveground C mostly as overstorey trees, and a significant reduction in understorey, dead trees and stumps.
Liubov Volkova; Christopher J. Weston. Effect of thinning and burning fuel reduction treatments on forest carbon and bushfire fuel hazard in Eucalyptus sieberi forests of South-Eastern Australia. Science of The Total Environment 2019, 694, 133708 .
AMA StyleLiubov Volkova, Christopher J. Weston. Effect of thinning and burning fuel reduction treatments on forest carbon and bushfire fuel hazard in Eucalyptus sieberi forests of South-Eastern Australia. Science of The Total Environment. 2019; 694 ():133708.
Chicago/Turabian StyleLiubov Volkova; Christopher J. Weston. 2019. "Effect of thinning and burning fuel reduction treatments on forest carbon and bushfire fuel hazard in Eucalyptus sieberi forests of South-Eastern Australia." Science of The Total Environment 694, no. : 133708.
Liubov Volkova; Stephen H. Roxburgh; Nicholas C. Surawski; C.P. (Mick) Meyer; Christopher J. Weston. Improving reporting of national greenhouse gas emissions from forest fires for emission reduction benefits: An example from Australia. Environmental Science & Policy 2019, 94, 49 -62.
AMA StyleLiubov Volkova, Stephen H. Roxburgh, Nicholas C. Surawski, C.P. (Mick) Meyer, Christopher J. Weston. Improving reporting of national greenhouse gas emissions from forest fires for emission reduction benefits: An example from Australia. Environmental Science & Policy. 2019; 94 ():49-62.
Chicago/Turabian StyleLiubov Volkova; Stephen H. Roxburgh; Nicholas C. Surawski; C.P. (Mick) Meyer; Christopher J. Weston. 2019. "Improving reporting of national greenhouse gas emissions from forest fires for emission reduction benefits: An example from Australia." Environmental Science & Policy 94, no. : 49-62.
This is a study of the re-accumulation of bushfire fuels following both prescribed fire of low fireline intensity (10,000 kW m−1) in Australian Eucalyptus open forests of differing annual rainfall. Repeated measurements over 5 to 7 years of litter, elevated fuels, coarse woody debris, and bark revealed more rapid fuel recovery in higher rainfall forests compared with lower rainfall forests, following prescribed fire. In prescribed-burnt forests with mean annual rainfall 900–950 mm all fuel categories recovered to very high within seven years, with elevated fuels exceeding pre-fire loads by up to 200%. No fuels in prescribed-burnt forests with mean annual rainfall 600–650 mm recovered to pre-fire loads after six years suggesting that rainfall is an important driver of the rate of fuels recovery. High intensity wildfire in lower rainfall forests (600-650 mm) stimulated the rapid recovery of elevated fuels to over 600% of pre-fire loads – effectively transforming open forest formations into shrublands over the 6 years after fire. The recovery of elevated fuels following both prescribed fire in high rainfall forests and wildfire in low rainfall forests did not follow a gradual negative exponential increase often approximated by an Olson curve, but peaked early after fires. This suggests that the Olson recovery function, the default for predicting loads for these fuels in the operational fire behaviour models in use in south-eastern Australia, may not be appropriate in all cases. Fire simulations were run for forests burnt in wildfires using default (forest) and observed (shrubland) vegetation types. Under weather conditions similar to the previous wildfire, predictions for fireline intensities and the rate of spread would be at least 50% greater in transitional shrubland than forest, emphasizing the importance of accounting for vegetation dynamics for safe response management.
Liubov Volkova; Alexander G. Weiss Aparicio; Christopher J. Weston. Fire intensity effects on post-fire fuel recovery in Eucalyptus open forests of south-eastern Australia. Science of The Total Environment 2019, 670, 328 -336.
AMA StyleLiubov Volkova, Alexander G. Weiss Aparicio, Christopher J. Weston. Fire intensity effects on post-fire fuel recovery in Eucalyptus open forests of south-eastern Australia. Science of The Total Environment. 2019; 670 ():328-336.
Chicago/Turabian StyleLiubov Volkova; Alexander G. Weiss Aparicio; Christopher J. Weston. 2019. "Fire intensity effects on post-fire fuel recovery in Eucalyptus open forests of south-eastern Australia." Science of The Total Environment 670, no. : 328-336.
On a global scale, about 15.5% of forests are administered through community-based forestry programs that offer the opportunity for enhanced carbon sequestration while maintaining the supply of more traditional goods and services such as cooking fuels, animal fodder and bedding. A challenge in community forest (CF) management is to realize their carbon value without compromising their role in the provision of these traditional goods and services. In this study of CF dominated by Pinus roxburghii in the Phalebas region of Nepal, the impacts of stand composition and geographic aspect on aboveground forest carbon is investigated as a means to optimize CF management for both traditional values and for emerging carbon market values. The aboveground carbon of mixed and monospecific stands of Pinus roxburghii was estimated using a combination of destructive sampling and species-specific allometric equations. On average, monospecific stands contained 106.2 Mg C ha-1 in aboveground tree biomass, significantly more than mixed stands at 73.1 Mg C ha-1 (p = 0.022). Similarly, stands growing on northern aspects (northeast 124.8 Mg C ha-1, northwest 100.9 Mg C ha-1) stored significantly more carbon (p = 0.002) than southern aspects (southeast 75.3 Mg C ha-1, southwest 57.6 Mg C ha-1), reflecting the more favorable growing conditions of northern aspects. These results suggest monospecific stands planted on northern aspects may be best suited for management to achieve carbon benefits, whilst mixed-species stands on southern aspects may be better suited for biodiversity conservation and supporting livelihoods. To maintain and increase carbon value, community forestry may need to implement nutrient return practices to limit the impact of sustained nutrient removals on stand productivity.
Shiva Pariyar; Liubov Volkova; Ram P. Sharma; Ramesh Sunam; Christopher J. Weston. Aboveground carbon of community-managed Chirpine (Pinus roxburghii Sarg.) forests of Nepal based on stand types and geographic aspects. PeerJ 2019, 7, e6494 .
AMA StyleShiva Pariyar, Liubov Volkova, Ram P. Sharma, Ramesh Sunam, Christopher J. Weston. Aboveground carbon of community-managed Chirpine (Pinus roxburghii Sarg.) forests of Nepal based on stand types and geographic aspects. PeerJ. 2019; 7 ():e6494.
Chicago/Turabian StyleShiva Pariyar; Liubov Volkova; Ram P. Sharma; Ramesh Sunam; Christopher J. Weston. 2019. "Aboveground carbon of community-managed Chirpine (Pinus roxburghii Sarg.) forests of Nepal based on stand types and geographic aspects." PeerJ 7, no. : e6494.
Environmental cycling of the toxic metal mercury (Hg) is ubiquitous, and still not completely understood. Volatilisation and emission of mercury from vegetation, litter and soil during burning represents a significant return pathway for previously-deposited atmospheric mercury. Rates of such emission vary widely across ecosystems as they are dependent on species-specific uptake of atmospheric mercury as well as fire return frequencies. Wildfire burning in Australia is currently thought to contribute between 1 and 5 % of the global total of mercury emissions, yet no modelling efforts to date have utilised local mercury emission factors (mass of emitted mercury per mass of dry fuel) or local mercury emission ratios (ratio of emitted mercury to another emitted species, typically carbon monoxide). Here we present laboratory and field investigations into mercury emission from burning of surface fuels in dry sclerophyll forests, native to the temperate south-eastern region of Australia. From laboratory data we found that fire behaviour — in particular combustion phase — has a large influence on mercury emission and hence emission ratios. Further, emission of mercury was predominantly in gaseous form with particulate-bound mercury representing < 1 % of total mercury emission. Importantly, emission factors and emission ratios with respect to carbon monoxide and carbon dioxide, from both laboratory and field data all show that gaseous mercury emission from biomass burning in Australian dry sclerophyll forests is currently overestimated by around 60 %. Based on these results, we recommend a mercury emission factor of 28.7 ± 8.1 μg Hg kg−1 dry fuel, and emission ratio of gaseous elemental mercury relative to carbon monoxide of 0.58 ± 0.01 ×10−7, for estimation of mercury release from the combustion of Australian dry sclerophyll litter.
Dean Howard; Katrina Macsween; Grant C. Edwards; Maximilien Desservettaz; Elise-Andrée Guérette; Clare Paton-Walsh; Nicholas C. Surawski; Andrew Sullivan; Christopher Weston; Liubov Volkova; Jennifer Powell; Melita Keywood; Fabienne Reisen; C.P. (Mick) Meyer. Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations. Atmospheric Environment 2018, 202, 17 -27.
AMA StyleDean Howard, Katrina Macsween, Grant C. Edwards, Maximilien Desservettaz, Elise-Andrée Guérette, Clare Paton-Walsh, Nicholas C. Surawski, Andrew Sullivan, Christopher Weston, Liubov Volkova, Jennifer Powell, Melita Keywood, Fabienne Reisen, C.P. (Mick) Meyer. Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations. Atmospheric Environment. 2018; 202 ():17-27.
Chicago/Turabian StyleDean Howard; Katrina Macsween; Grant C. Edwards; Maximilien Desservettaz; Elise-Andrée Guérette; Clare Paton-Walsh; Nicholas C. Surawski; Andrew Sullivan; Christopher Weston; Liubov Volkova; Jennifer Powell; Melita Keywood; Fabienne Reisen; C.P. (Mick) Meyer. 2018. "Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations." Atmospheric Environment 202, no. : 17-27.
Andrew Sullivan; N.C. Surawski; D. Crawford; R.J. Hurley; Liubov Volkova; C.J. Weston; C.P. Meyer. Effect of woody debris on the rate of spread of surface fires in forest fuels in a combustion wind tunnel. Forest Ecology and Management 2018, 424, 236 -245.
AMA StyleAndrew Sullivan, N.C. Surawski, D. Crawford, R.J. Hurley, Liubov Volkova, C.J. Weston, C.P. Meyer. Effect of woody debris on the rate of spread of surface fires in forest fuels in a combustion wind tunnel. Forest Ecology and Management. 2018; 424 ():236-245.
Chicago/Turabian StyleAndrew Sullivan; N.C. Surawski; D. Crawford; R.J. Hurley; Liubov Volkova; C.J. Weston; C.P. Meyer. 2018. "Effect of woody debris on the rate of spread of surface fires in forest fuels in a combustion wind tunnel." Forest Ecology and Management 424, no. : 236-245.
The increasing regional and global impact of wildfires on the environment, and particularly on the human population, is becoming a focus of the research community. Both fire behaviour and smoke dispersion models are now underpinning strategic and tactical fire management by many government agencies and therefore model accuracy at regional and local scales is increasingly important. This demands accuracy of all the components of the model systems, biomass fuel loads being among the more significant. Validation of spatial fuels maps at a regional scale is uncommon; in part due to the limited availability of independent observations of fuel loads, and in part due to a focus on the impact of model outputs. In this study we evaluate two approaches for estimating fuel loads at a regional scale and test their accuracy against an extensive set of field observations for the State of Victoria, Australia. The first approach, which assumes that fuel accumulation is an attribute of the vegetation class, was developed for the fire behaviour model Phoenix Rapid-Fire, with apparent success; the second approach applies the Community Atmosphere Biosphere Land Exchange (CABLE) process-based terrestrial biosphere model, implemented at high resolution across the Australian continent. We show that while neither model is accurate over the full range of fine and coarse fuel loads, CABLE biases can be corrected for the full regional domain with a single linear correction, however the classification based Phoenix requires a matrix of factors to correct its bias. We conclude that these examples illustrate that the benefits of simplicity and resolution inherent in classification-based models do not compensate for their lack of accuracy, and that lower resolution but inherently more accurate carbon-cycle models may be preferable for estimating fuel loads for input into smoke dispersion models.
Liubov Volkova; C.P. (Mick) Meyer; Vanessa Haverd; Christopher J. Weston. A data - Model fusion methodology for mapping bushfire fuels for smoke emissions forecasting in forested landscapes of south-eastern Australia. Journal of Environmental Management 2018, 222, 21 -29.
AMA StyleLiubov Volkova, C.P. (Mick) Meyer, Vanessa Haverd, Christopher J. Weston. A data - Model fusion methodology for mapping bushfire fuels for smoke emissions forecasting in forested landscapes of south-eastern Australia. Journal of Environmental Management. 2018; 222 ():21-29.
Chicago/Turabian StyleLiubov Volkova; C.P. (Mick) Meyer; Vanessa Haverd; Christopher J. Weston. 2018. "A data - Model fusion methodology for mapping bushfire fuels for smoke emissions forecasting in forested landscapes of south-eastern Australia." Journal of Environmental Management 222, no. : 21-29.
In fire‐prone areas such as southern Australia and parts of the United States, prescribed burning is a common fire management tool to reduce fuel load for wildfire suppression purposes. The burns are typically undertaken during calm and stable conditions when the burn extent and duration can be carefully controlled. This often coincides with poor atmospheric ventilation, leading to a build‐up of smoke which can impact air quality and human health. The low intensity of these burns also means that the plume is less buoyant and the main impact on local populations is due to emissions during the slow and prolonged smouldering combustion of heavy fuels. This study presents emissions measurements of PM2.5 at prescribed burns in eucalypt forests of southern Australia using a smoke collection method suitable for both flaming combustion of fine fuels and residual smouldering combustion of heavy fuels and logs. The median PM2.5 emission factors (EFs) measured were 16.9 g kg‐1 fuel during flaming combustion and 38.8 g kg‐1 fuel during smouldering combustion. The correlation between PM2.5 EFs and modified combustion efficiency (MCE) highlights two distinct trends at low MCE, attributed to the distinct combustion processes of glowing char combustion and pyrolysis. Hence two distinct relationships were developed that best fitted the measurements and that can be used to extrapolate measured EFs to a wider range of fuel and burning conditions. The results from this study addressed a gap in our knowledge of particle emissions during burns in eucalypt forests under different burning conditions and help to better forecast and manage air quality impacts from prescribed burns on nearby communities.
F. Reisen; C. P. Meyer; C. J. Weston; L. Volkova. Ground-Based Field Measurements of PM2.5 Emission Factors From Flaming and Smoldering Combustion in Eucalypt Forests. Journal of Geophysical Research: Atmospheres 2018, 1 .
AMA StyleF. Reisen, C. P. Meyer, C. J. Weston, L. Volkova. Ground-Based Field Measurements of PM2.5 Emission Factors From Flaming and Smoldering Combustion in Eucalypt Forests. Journal of Geophysical Research: Atmospheres. 2018; ():1.
Chicago/Turabian StyleF. Reisen; C. P. Meyer; C. J. Weston; L. Volkova. 2018. "Ground-Based Field Measurements of PM2.5 Emission Factors From Flaming and Smoldering Combustion in Eucalypt Forests." Journal of Geophysical Research: Atmospheres , no. : 1.
Analysis of growth and biomass turnover in natural forests of Eucalyptus regnans, the world's tallest angiosperm, reveals it is also the world's most productive forest type, with fire disturbance an important mediator of net primary productivity (NPP). A comprehensive empirical database was used to calculate the averaged temporal pattern of NPP from regeneration to 250 years age. NPP peaks at 23.1±3.8 (95% inter‐quantile range) Mg C ha−1 yr−1 at age 14 years, and declines gradually to about 9.2±0.8 Mg C ha−1 yr−1 at 130 years, with an average NPP over 250 years of 11.4±1.1 Mg C ha−1 yr−1, a value similar to the most productive temperate and tropical forests around the world. We then applied the age‐class distribution of E. regnans resulting from relatively recent historical fires to estimate current NPP for the forest estate. Values of NPP were 40% higher (13 Mg C ha−1 yr−1) than if forests were assumed to be at maturity (9.2 Mg C ha−1 yr−1). The empirically‐derived NPP time‐series for the E. regnans estate was then compared against predictions from 21 global circulation models, showing that none of them had the capacity to simulate a post‐disturbance peak in NPP, as found in E. regnans. The potential importance of disturbance impacts on NPP was further tested by applying a similar approach to the temperate forests of conterminous USA and of China. Allowing for the effects of disturbance, NPP summed across both regions was on average 11% (or 194 Tg C yr−1) greater than if all forests were assumed to be in a mature state. The results illustrate the importance of accounting for past disturbance history and growth stage when estimating forest primary productivity, with implications for carbon balance modelling at local to global scales. This article is protected by copyright. All rights reserved.
Liubov Volkova; Stephen H Roxburgh; Christopher J Weston; Richard G Benyon; Andrew L Sullivan; Philip J Polglase. Importance of disturbance history on net primary productivity in the world's most productive forests and implications for the global carbon cycle. Global Change Biology 2018, 24, 4293 -4303.
AMA StyleLiubov Volkova, Stephen H Roxburgh, Christopher J Weston, Richard G Benyon, Andrew L Sullivan, Philip J Polglase. Importance of disturbance history on net primary productivity in the world's most productive forests and implications for the global carbon cycle. Global Change Biology. 2018; 24 (9):4293-4303.
Chicago/Turabian StyleLiubov Volkova; Stephen H Roxburgh; Christopher J Weston; Richard G Benyon; Andrew L Sullivan; Philip J Polglase. 2018. "Importance of disturbance history on net primary productivity in the world's most productive forests and implications for the global carbon cycle." Global Change Biology 24, no. 9: 4293-4303.
We characterised trace gas emissions from Australian temperate forest fires through a mixture of open-path Fourier transform infrared (OP-FTIR) measurements and selective ion flow tube mass spectrometry (SIFT-MS) and White cell FTIR analysis of grab samples. We report emission factors for a total of 25 trace gas species measured in smoke from nine prescribed fires. We find significant dependence on modified combustion efficiency (MCE) for some species, although regional differences indicate that the use of MCE as a proxy may be limited. We also find that the fire-integrated MCE values derived from our in situ on-the-ground open-path measurements are not significantly different from those reported for airborne measurements of smoke from fires in the same ecosystem. We then compare our average emission factors to those measured for temperate forest fires elsewhere (North America) and for fires in another dominant Australian ecosystem (savanna) and find significant differences in both cases. Indeed, we find that although the emission factors of some species agree within 20 %, including those of hydrogen cyanide, ethene, methanol, formaldehyde and 1,3-butadiene, others, such as acetic acid, ethanol, monoterpenes, ammonia, acetonitrile and pyrrole, differ by a factor of 2 or more. This indicates that the use of ecosystem-specific emission factors is warranted for applications involving emissions from Australian forest fires.
Elise-Andrée Guérette; Clare Paton-Walsh; Maximilien Desservettaz; Thomas E. L. Smith; Liubov Volkova; Christopher J. Weston; Carl P. Meyer. Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency. Atmospheric Chemistry and Physics 2018, 18, 3717 -3735.
AMA StyleElise-Andrée Guérette, Clare Paton-Walsh, Maximilien Desservettaz, Thomas E. L. Smith, Liubov Volkova, Christopher J. Weston, Carl P. Meyer. Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency. Atmospheric Chemistry and Physics. 2018; 18 (5):3717-3735.
Chicago/Turabian StyleElise-Andrée Guérette; Clare Paton-Walsh; Maximilien Desservettaz; Thomas E. L. Smith; Liubov Volkova; Christopher J. Weston; Carl P. Meyer. 2018. "Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency." Atmospheric Chemistry and Physics 18, no. 5: 3717-3735.
Elise-Andrée Guérette; Clare Paton-Walsh; Maximilien Desservettaz; Thomas E. L. Smith; Liubov Volkova; Christopher J. Weston; C. P. Meyer. Supplementary material to "Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency". 2017, 1 .
AMA StyleElise-Andrée Guérette, Clare Paton-Walsh, Maximilien Desservettaz, Thomas E. L. Smith, Liubov Volkova, Christopher J. Weston, C. P. Meyer. Supplementary material to "Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency". . 2017; ():1.
Chicago/Turabian StyleElise-Andrée Guérette; Clare Paton-Walsh; Maximilien Desservettaz; Thomas E. L. Smith; Liubov Volkova; Christopher J. Weston; C. P. Meyer. 2017. "Supplementary material to "Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency"." , no. : 1.
We characterised trace gas emissions from Australian temperate forest fires through a mixture of in situ open-path FTIR measurements spectroscopy and selective ion flow tube mass spectrometry (SIFT-MS) and White cell FTIR spectroscopy of grab samples. We report emission factors for a total of 25 trace gas species measured in smoke from nine prescribed fires. We find significant dependence on modified combustion efficiency (MCE) for some species, although regional differences indicate that the use of MCE as a proxy may be limited. We also find that the fire-integrated MCE values derived from our in situ on-the-ground open-path measurements are not significantly different from those reported for airborne measurements of smoke from fires in the same ecosystem. We then compare our average emission factors to those measured for fires in North American temperate ecosystems and for fires in Australian savanna and find that, although emission factors of some species agree within 20 %, others differ by a factor of 2 or more. This indicates that the use of ecosystem-specific emission factors is warranted for applications involving emissions from Australian forest fires.
Elise-Andrée Guérette; Clare Paton-Walsh; Maximilien Desservettaz; Thomas E. L. Smith; Liubov Volkova; Christopher J. Weston; C. P. Meyer. Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency. 2017, 2017, 1 -29.
AMA StyleElise-Andrée Guérette, Clare Paton-Walsh, Maximilien Desservettaz, Thomas E. L. Smith, Liubov Volkova, Christopher J. Weston, C. P. Meyer. Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency. . 2017; 2017 ():1-29.
Chicago/Turabian StyleElise-Andrée Guérette; Clare Paton-Walsh; Maximilien Desservettaz; Thomas E. L. Smith; Liubov Volkova; Christopher J. Weston; C. P. Meyer. 2017. "Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency." 2017, no. : 1-29.
Forest mega-fires have become a global phenomenon in recent decades including in south-eastern Australia where large areas of forest have been fire-killed with loss of human lives and property and impacting carbon sequestration and greenhouse gas emissions. The vast extent and impact of mega-fires has induced a re-evaluation of fuel reduction methods as a key management strategy in wildfire risk mitigation in many countries. This study investigated the impact of a commercial thinning in Eucalyptus delegatensis forest on fuel hazard, fuel loads and wildfire behaviour, eight years after completion of a bay and outrow thinning operation. At the stand level, thinning reduced overstorey tree stocking by more than 50%, increased canopy openness and stimulated the growth of retained trees. Thinning also encouraged the profuse regeneration of over 1000 saplings ha−1 of E. delegatensis, mostly in the outrows, compared with no sapling regeneration in unthinned forest. A system of additive biomass equations was developed to estimate total biomass and component biomass (stem wood, bark, branches and foliage) of individual trees. The aboveground tree carbon was 433 ± 49 Mg C ha−1 in unthinned forest and 322 ± 47 Mg C ha−1 in thinned forest. Thinning decreased surface fuel hazard ratings and fuel loads but had no significant effect on the mass of coarse woody fuels. Fire simulation under severe to extreme weather conditions, as occurred in the 2006/7 Great Divide Fires, indicated an almost 30% reduction in fireline intensity and about 20% reduction in the rate of spread and spotting distance in thinned forest compared with unthinned forest. This study indicates the potential of thinning to reduce wildfire severity and to increase the fire-survival of E. delegatensis.
Liubov Volkova; Huiquan Bi; James Hilton; Christopher J. Weston. Impact of mechanical thinning on forest carbon, fuel hazard and simulated fire behaviour in Eucalyptus delegatensis forest of south-eastern Australia. Forest Ecology and Management 2017, 405, 92 -100.
AMA StyleLiubov Volkova, Huiquan Bi, James Hilton, Christopher J. Weston. Impact of mechanical thinning on forest carbon, fuel hazard and simulated fire behaviour in Eucalyptus delegatensis forest of south-eastern Australia. Forest Ecology and Management. 2017; 405 ():92-100.
Chicago/Turabian StyleLiubov Volkova; Huiquan Bi; James Hilton; Christopher J. Weston. 2017. "Impact of mechanical thinning on forest carbon, fuel hazard and simulated fire behaviour in Eucalyptus delegatensis forest of south-eastern Australia." Forest Ecology and Management 405, no. : 92-100.