A patch mosaic burning system for conservation areas in southern African savannas

2001 ◽  
Vol 10 (2) ◽  
pp. 169 ◽  
Author(s):  
B.H. Brockett ◽  
H.C. Biggs ◽  
B.W. van Wilgen
Keyword(s):  
Prescribed Burning ◽  
Fire Regime ◽  
Weather Conditions ◽  
Dry Season ◽  
Fuel Load ◽  
Fire Season ◽  
Fire Intensity ◽  
Target Area ◽  
Conservation Areas ◽  
Percentage Area

Fire-prone savanna ecosystems in southern African conservation areas are managed by prescribed burning in order to conserve biodiversity. A prescribed burning system designed to maximise the benefits of a diverse fire regime in savanna conservation areas is described. The area burnt per year is a function of the grass fuel load, and the number of fires per year is a function of the percentage area burnt. Fires are point-ignited, under a range of fuel and weather conditions, and allowed to burn out by themselves. The seasonal distribution of planned fires over a year is dependent on the number of fires. Early dry season fires (May–June) tend to be small because fuels have not yet fully cured, while late season fires (August–November) are larger. More fires are ignited in the early dry season, with fewer in the late dry season. The seasonality, area burnt, and fire intensity are spatially and temporally varied across a landscape. This should result in the creation of mosaics, which should vary in extent and existence in time. Envelopes for the accumulated percentage to be burnt per month, over the specified fire season, together with upper and lower buffers to the target area are proposed. The system was formalised after 8 years of development and testing in Pilanesberg National Park, South Africa. The spatial heterogeneity of fire patterns increased over the latter years of implementation. This fire management system is recommended for savanna conservation areas of >20 000 ha in size.

scholarly journals Fire regimes in eastern coastal fynbos: Imperatives and thresholds in managing for diversity

Koedoe ◽  
2013 ◽  
Vol 55 (1) ◽  
Author(s):  
Tineke Kraaij ◽  
Richard M. Cowling ◽  
Brian W. Van Wilgen
Keyword(s):  
Fire Ecology ◽  
Large Scale ◽  
Prescribed Burning ◽  
Fire Regime ◽  
Fire Regimes ◽  
Fire Season ◽  
Fire Intensity ◽  
Plant Management ◽  
Alien Plant ◽  
Invasive Alien Plant

Until recently, fire ecology was poorly understood in the eastern coastal region of the Cape Floral Kingdom (CFK), South Africa. Rainfall in the area is aseasonal and temperatures are milder than in the winter-rainfall and drier inland parts of the CFK, with implications for the management of fire regimes. We synthesised the findings of a research programme focused on informing ecologically sound management of fire in eastern coastal fynbos shrublands and explored potential east–west trends at the scales of study area and CFK in terms of fire return interval (FRI) and fire season. FRIs (8–26 years; 1980–2010) were comparable to those elsewhere in the CFK and appeared to be shorter in the eastern Tsitsikamma than in the western Outeniqua halves of the study area. Proteaceae juvenile periods (4–9 years) and post-fire recruitment success suggested that for biodiversity conservation purposes, FRIs should be ≥ 9 years in eastern coastal fynbos. Collectively, findings on the seasonality of actual fires and the seasonality of fire danger weather, lightning and post-fire proteoid recruitment suggested that fires in eastern coastal fynbos are not limited to any particular season. We articulated these findings into ecological thresholds pertaining to the different elements of the fire regime in eastern coastal fynbos, to guide adaptive management of fire in the Garden Route National Park and elsewhere in the region.Conservation implications: Wildfires are likely to remain dominant in eastern coastal fynbos, whilst large-scale implementation of prescribed burning is unattainable. Fires occurring in any season are not a reason for concern, although other constraints remain: the need for sufficient fire intensity, safety requirements, and integration of fire and invasive alien plant management.

scholarly journals Regional seasonality of fire size and fire weather conditions across Australia's northern savanna

2020 ◽  
Vol 29 (1) ◽  
pp. 1 ◽  
Author(s):  
Justin J. Perry ◽  
Garry D. Cook ◽  
Erin Graham ◽  
C. P. (Mick) Meyer ◽  
Helen T. Murphy ◽  
...  
Keyword(s):  
Prescribed Burning ◽  
Fire Regime ◽  
Weather Conditions ◽  
Temporal Variations ◽  
Dry Season ◽  
Fire Weather ◽  
Fire Size ◽  
Spatial Consistency ◽  
In Fire ◽  
Extreme Fire

Australia’s northern savannas have among the highest fire frequencies in the world. The climate is monsoonal, with a long, dry season of up to 9 months, during which most fires occur. The Australian Government’s Emissions Reduction Fund allows land managers to generate carbon credits by abating the direct emissions of CO2 equivalent gases via prescribed burning that shifts the fire regime from predominantly large, high-intensity late dry season fires to a more benign, early dry season fire regime. However, the Australian savannas are vast and there is significant variation in weather conditions and seasonality, which is likely to result in spatial and temporal variations in the commencement and length of late dry season conditions. Here, we assess the temporal and spatial consistency of the commencement of late dry season conditions, defined as those months that maximise fire size and where the most extreme fire weather conditions exist. The results demonstrate that significant yearly, seasonal and spatial variations in fire size and fire weather conditions exist, both within and between bioregions. The effective start of late dry season conditions, as defined by those months that maximise fire size and where the most extreme fire weather variables exist, is variable across the savannas.

scholarly journals Prescribed Burning Reduces Large, High-Intensity Wildfires and Emissions in the Brazilian Savanna

Fire ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 56
Author(s):  
Filippe L.M. Santos ◽  
Joana Nogueira ◽  
Rodrigo A. F. de Souza ◽  
Rodrigo M. Falleiro ◽  
Isabel B. Schmidt ◽  
...  
Keyword(s):  
High Intensity ◽  
Prescribed Burning ◽  
Fire Management ◽  
Fire Regime ◽  
Scientific Evidence ◽  
Brazilian Savanna ◽  
Fire Season ◽  
Fire Intensity ◽  
Burned Area ◽  
Fire Policy

Brazil has recently (2014) changed from a zero-fire policy to an Integrated Fire Management (IFM) program with the active use of prescribed burning (PB) in federal Protected Areas (PA) and Indigenous Territories (IT) of the Brazilian savanna (Cerrado). PB is commonly applied in the management of fire-prone ecosystems to mitigate large, high-intensity wildfires, the associated emissions, and high fire suppression costs. However, the effectiveness of such fire management in reducing large wildfires and emissions over Brazil remains mostly unevaluated. Here, we aim to fill the gap in the scientific evidence of the PB benefits by relying on the most up-to-date, satellite-derived fire datasets of burned area (BA), fire size, duration, emissions, and intensity from 2003 to 2018. We focused on two Cerrado ITs with different sizes and hydrological regimes, Xerente and Araguaia, where IFM has been in place since 2015. To understand fire regime dynamics, we divided the study period into three phases according to the prevalent fire policy and the individual fire scars into four size classes. We considered two fire seasons: management fire season (MFS, which goes from rainy to mid-dry season, when PBs are undertaken) and wildfires season (WFS, when PBs are not performed and fires tend to grow out of control). Our results show that the implementation of the IFM program was responsible for a decrease of the areas affected by high fire recurrence in Xerente and Araguaia, when compared with the Zero Fire Phase (2008–2013). In both regions, PB effectively reduced the large wildfires occurrence, the number of medium and large scars, fire intensity, and emissions, changing the prevalent fire season from the WFS to the MFS. Such reductions are significant since WFS causes higher negative impacts on biodiversity conservation and higher greenhouse gas emissions. We conclude that the effect on wildfires can still be reduced if effective fire management policies, including PB, continue to be implemented during the coming decades.

Does season affect fire behaviour in the Cerrado?

2017 ◽  
Vol 26 (5) ◽  
pp. 427 ◽  
Author(s):  
Mariana Ninno Rissi ◽  
M. Jaime Baeza ◽  
Elizabeth Gorgone-Barbosa ◽  
Talita Zupo ◽  
Alessandra Fidelis
Keyword(s):  
Dry Season ◽  
Flame Height ◽  
Fuel Load ◽  
Fire Season ◽  
Fire Intensity ◽  
Fire Behaviour ◽  
Dead Biomass ◽  
Management Plans ◽  
Fire Exclusion ◽  
Fuel Moisture Content

Fire has played an important role in the plant dynamics and diversity of the Cerrado for millions of years. We evaluated fire behaviour in different fire seasons in areas of an open savanna, providing information for fire management plans. It has been hypothesised that early fires (May – end of the rainy season) will be less intense than those conducted in the middle and end of the dry season (July and October) owing to the amount of dead biomass accumulated. Therefore, we compared fire behaviour in early, mid- and late dry season, evaluating the main fire and environmental variables. Fire intensity was mainly influenced by the combination of dead fuel percentage and fuel load. Even though this combination was the best model to explain fire intensity variability, fire parameters (including fire intensity) did not differ between fire seasons. Flame height was best explained by dead fuel percentage + fuel moisture content, dead fuel percentage + fuel load and also by dead fuel percentage. Our study showed that, in areas with fire exclusion for 2 years, fire season did not influence fire parameters and fire behaviour and the main factors influencing fire intensity were the proportion of dead biomass and total fuel load.

scholarly journals Prescribed burning in a mediterranean-climate region mitigates the disturbance by bushfire to a critical food resource for an endangered bird, the Carnaby’s cockatoo

Fire Ecology ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Valerie S. Densmore ◽  
Emma S. Clingan
Keyword(s):  
Seed Production ◽  
Prescribed Burning ◽  
Fire Regime ◽  
Fire Hazard ◽  
Food Resource ◽  
Management Tool ◽  
Fire Intensity ◽  
Prescribed Burns ◽  
Low Intensity ◽  
Percentage Survival

Abstract Background Prescribed burning is used to reduce fire hazard in highly flammable vegetation types, including Banksia L.f. woodland that occurs on the Swan Coastal Plain (SCP), Western Australia, Australia. The 2016 census recorded well over 1.9 million people living on the SCP, which also encompasses Perth, the fourth largest city in Australia. Banksia woodland is prone to frequent ignitions that can cause extensive bushfires that consume canopy-stored banksia seeds, a critical food resource for an endangered bird, the Carnaby’s cockatoo (Calyptorynchus latirostris, Carnaby 1948). The time needed for banksias to reach maturity and maximum seed production is several years longer than the typical interval between prescribed burns. We compared prescribed burns to bushfires and unburned sites at three locations in banksia woodland to determine whether low-intensity prescribed burns affect the number of adult banksias and their seed production. Study sites were matched to the same vegetation complex, fire regime, and time-since-fire to isolate fire intensity as a variable. Results Headfire rates of spread and differenced normalized burn ratios indicated that prescribed burning was generally of a much lower intensity than bushfire. The percentage survival of adult banksias and their production of cones and follicles (seeds) did not decrease during the first three years following a prescribed burn. However, survival and seed production were significantly diminished followed high-intensity bushfire. Thus, carrying capacity for Carnaby’s cockatoo was unchanged by prescribed burning but decreased markedly following bushfire in banksia woodland. Conclusions These results suggest that prescribed burning is markedly different from bushfire when considering appropriate fire intervals to conserve canopy habitats in fire-resilient vegetation communities. Therefore, low-intensity prescribed burning represents a viable management tool to reduce the frequency and extent of bushfire impacts on banksia woodland and Carnaby’s cockatoo.

Fuel and fire characteristics in savanna - woodland of West Africa in relation to grazing and dominant grass type

2007 ◽  
Vol 16 (5) ◽  
pp. 531 ◽  
Author(s):  
Patrice Savadogo ◽  
Didier Zida ◽  
Louis Sawadogo ◽  
Daniel Tiveau ◽  
Mulualem Tigabu ◽  
...  
Keyword(s):  
Prescribed Burning ◽  
Management Tool ◽  
Fuel Load ◽  
Maximum Temperature ◽  
Fire Intensity ◽  
Fire Behaviour ◽  
Savanna Woodland ◽  
Vegetation Height ◽  
Average Maximum ◽  
Dominant Grass

Fuel characteristics, fire behaviour and temperature were studied in relation to grazing, dominant grass type and wind direction in West African savanna–woodland by lighting 32 prescribed early fires. Grazing significantly reduced the vegetation height, total fuel load, and dead and live fuel fractions whereas plots dominated by perennial grasses had higher values for vegetation height, total fuel load and the quantity of live fuel load. Although fire intensity remained insensitive (P > 0.05) to any of these factors, fuel consumption was significantly (P = 0.021) reduced by grazing, rate of spread was faster in head fire (P = 0.012), and flame length was shorter in head fire than back fire (P = 0.044). The average maximum temperature was higher (P < 0.05) on non-grazed plots, on plots dominated by annual grasses, on plots subjected to head fire, and at the soil surface. Lethal temperature residence time showed a nearly similar trend to fire temperature. Wind speed and total fuel load were best predictors of fire behaviour parameters (R2 ranging from 0.557 to 0.862). It can be concluded that grazing could be used as a management tool to modify fire behaviour, back fire should be carried out during prescribed burning to lower fire severity, and the fire behaviour models can be employed to guide prescribed early fire in the study area.

Simulating the effectiveness of prescribed burning at altering wildfire behaviour in Tasmania, Australia

2018 ◽  
Vol 27 (1) ◽  
pp. 15 ◽  
Author(s):  
James M. Furlaud ◽  
Grant J. Williamson ◽  
David M. J. S. Bowman
Keyword(s):  
Prescribed Burning ◽  
Vegetation Type ◽  
Weather Conditions ◽  
Statistical Modelling ◽  
Fire Intensity ◽  
Fire Weather ◽  
Fire Behaviour ◽  
Large Area ◽  
Treatment Scenario ◽  
Wildfire Hazard

Prescribed burning is a widely accepted wildfire hazard reduction technique; however, knowledge of its effectiveness remains limited. To address this, we employ simulations of a widely used fire behaviour model across the ecologically diverse Australian island state of Tasmania. We simulate three broad scenarios: (1) no fuel treatment, (2) a maximal treatment, with the most possible prescribed burning within ecological constraints, and (3) 12 hypothetically more implementable state-wide prescribed-burning plans. In all simulations, we standardised fire-weather inputs to represent regionally typical dangerous fire-weather conditions. Statistical modelling showed that an unrealistically large maximal treatment scenario could reduce fire intensity in three flammable vegetation types, and reduce fire probability in almost every vegetation type. However, leverage analysis of the 12 more-realistic implementable plans indicated that such prescribed burning would have only a minimal effect, if any, on fire extent and that none of these prescribed-burning plans substantially reduced fire intensity. The study highlights that prescribed burning can theoretically mitigate wildfire, but that an unrealistically large area would need to be treated to affect fire behaviour across the island. Rather, optimisation of prescribed burning requires careful landscape design at the local scale. Such designs should be based on improved fire behaviour modelling, empirical measurement of fuels and analysis of actual wildfires.

scholarly journals An assessment of the implementation and outcomes of recent changes to fire management in the Kruger National Park

Koedoe ◽  
2008 ◽  
Vol 50 (1) ◽  
Author(s):  
Brian W. Van Wilgen ◽  
Navashni Govender ◽  
Sandra MacFadyen
Keyword(s):  
National Park ◽  
Fire Management ◽  
Fire Regime ◽  
Kruger National Park ◽  
Fire Intensity ◽  
Target Area ◽  
Large Fires ◽  
Sufficient Degree ◽  
Burnt Areas ◽  
In Fire

This paper reviews recent changes in fire management in the Kruger National Park, and assesses the resulting fire patterns against thresholds of potential concern. In 2002, a lightning-driven approach was replaced by an approach that combined point ignitions with unplanned and lightning fires. The approach aimed to burn an annual target area, determined by rainfall and fuel conditions, in point-ignition fires of different sizes. Most of the original fire-related thresholds of potential concern (TPCs) were incorporated into the new approach. The annual target area to be burnt ranged from 12 to 24% of the park between 2002 and 2006. The total area burnt generally exceeded the targets each year, and management fires accounted for less than half of the total area burnt. The fire regime was dominated by very large fires (> 5 000 ha) which accounted for 77% of the total area burnt. New TPCs were developed to assess whether the fire regime encompassed a sufficient degree of variability, in terms of fire intensity and the spatial distribution of burnt areas. After assessment and adjustment, it appears that these TPCs have not yet been exceeded. The point-ignition approach, and its evaluation in terms of variability and heterogeneity, is based on the untested assumption that a diverse fire regime will promote biodiversity. This assumption needs to be critically assessed. We recommend that the practice of point ignitions be continued, but that greater efforts be made to burn larger areas earlier in the season to reduce large and intense dry-season fires.

Contemporary fire regime risks to key ecological assets and processes in north Australian savannas

2015 ◽  
Vol 24 (6) ◽  
pp. 857 ◽  
Author(s):  
Andrew Edwards ◽  
Jeremy Russell-Smith ◽  
Mick Meyer
Keyword(s):  
Climate Change ◽  
Prescribed Burning ◽  
Fire Management ◽  
Fire Regime ◽  
Ghg Emissions ◽  
Fire Regimes ◽  
Dry Season ◽  
Suspended Sediment Transport ◽  
Change Models ◽  
Positive Effects

Despite the intact appearance of relatively unmodified north Australian savannas, mounting evidence indicates that contemporary fire regimes characterised by frequent, extensive and severe late dry season wildfires are having deleterious effects on a range of regional water, soil erosion, biodiversity conservation and greenhouse gas (GHG) emissions values. For the high rainfall (>1000 mm year–1) savannas (426 000 km2), we assessed the spatial effects of contemporary fire regimes within the context of ecosystem response models and three plausible alternative fire management scenarios on ecosystem attributes. Over the 2008–12 assessment period, mean annual fire frequency (0.53) comprised mostly late dry season fires. Although spatially variable, contemporary fire regimes resulted in substantial GHG emissions, hill slope erosion and suspended sediment transport, a slight decline in carbon biomass and slight positive effects on fire-vulnerable vegetation. Based on available climate change models and strategic fire management practice, we show that, relative to business-as-usual, improved fire management involving strategic prescribed burning results in substantial benefits to most ecosystem attributes, including under enhanced climate change conditions, whereas in the absence of improved fire management, climate change results in substantially worse outcomes.

A review of prescribed burning effectiveness in fire hazard reduction

2003 ◽  
Vol 12 (2) ◽  
pp. 117 ◽  
Author(s):  
Paulo M. Fernandes ◽  
Hermínio S. Botelho
Keyword(s):  
Prescribed Fire ◽  
Prescribed Burning ◽  
Fire Regime ◽  
Accumulation Rate ◽  
Fire Suppression ◽  
Fire Hazard ◽  
Weather Conditions ◽  
Management Tool ◽  
Adequate Treatment ◽  
Hazard Reduction

Wildfire hazard abatement is one of the major reasons to use prescribed burning. Computer simulation, case studies, and analysis of the fire regime in the presence of active prescribed burning programs in forest and shrubland generally indicate that this fuel management tool facilitates fire suppression efforts by reducing the intensity, size and damage of wildfires. However, the conclusions that can be drawn from the above approaches are limited, highlighting the need for more properly designed experiments addressing this question. Fuel accumulation rate frequently limits prescribed fire effectiveness to a short post-treatment period (2–4 years). Optimisation of the spatial pattern of fire application is critical but has been poorly addressed by research, and practical management guidelines are lacking to initiate this. Furthermore, adequate treatment efforts in terms of fire protection are constrained by operational, social and ecological issues. The best results of prescribed fire application are likely to be attained in heterogeneous landscapes and in climates where the likelihood of extreme weather conditions is low. Conclusive statements concerning the hazard-reduction potential of prescribed fire are not easily generalised, and will ultimately depend on the overall efficiency of the entire fire management process.

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