Unburnt Areas Research Articles

A seven‐year study of the response of woodland birds to a large‐scale wildfire and the role of proximity to unburnt habitat

AbstractFire is a major ecological driver in many Australian ecosystems, and large‐scale wildfires can impact on faunal assemblages at a landscape scale. Monitoring the response of the avian community and individual bird species following a 92 039 ha wildfire in the Pilliga Forest, in temperate inland south‐eastern Australia, showed an initial decline in species richness and changes in community composition, followed by gradual recovery. Recovery was not complete by the end of the seven‐year study. Eighteen species (including Speckled Warbler Chthonicola sagittata and Eastern Yellow Robin Eopsaltria australis) were identified as likely to be fire sensitive and nine species (including Australian Magpie Cracticus tibicen and Red‐capped Robin Petroica goodenovii) as likely to respond positively to fire at the time scale of this study. Another 11 species (including Dusky Woodswallow Artamus cyanopterus and Jacky Winter Microeca fascinans) appeared to favour burnt areas close to the fire edge. Guild‐level patterns included an overall negative response to fire by insectivores, granivores/frugivores and declining woodland birds and a positive response by predators. The avian community recovered more quickly at burnt sites close to (within 2 km of) the fire edge compared to more remote sites more than 4 km from unburnt habitat, suggesting that proximity to unburnt areas (and therefore fire extent) is likely to be a key consideration in understanding the post‐fire recovery of birds.

Evidence that post‐fire recovery of small mammals occurs primarily via in situ survival

AbstractAimAs climate change intensifies and wildfire frequency and scale increase, it is critical we develop a robust understanding of how species recover from these major disturbances. Here, we aim to determine whether source populations for recovery following large‐scale intense wildfires are derived from either in situ survival, or immigration from surrounding unburnt areas (ex situ). Secondly, we sought to determine whether habitat elements (e.g., logs) within the landscape facilitate in situ survival of small mammals during fires.LocationGrampians National Park, south‐eastern Australia.MethodsWe used long‐term post‐fire small mammal monitoring to investigate sources of recovery for small mammals, and camera trapping and habitat surveys immediately following large intense wildfires to assess evidence for and drivers of post‐fire survival.ResultsWe found no relationship between distance to unburnt vegetation and the occurrence of any native species, suggesting that in situ survival is the probable mechanism for recovery of post‐fire mammal populations, compared with immigration from external unburnt areas. We also show that key habitat elements such as rocks and large trees were associated with the occurrence of several species immediately post‐fire, suggesting a role for these features in facilitating the survival of species during and following fire.Main conclusionsWe present evidence for post‐fire recovery being driven by in situ survival. In situ survival is facilitated by small unburnt patches and habitat elements in burnt areas. These surviving individuals become the founders for subsequent post‐fire population recovery. Given that globally we are seeing increasingly frequent large‐scale wildfires driven by climate change, the capacity for in situ survival will help mitigate some of the fire‐related impacts of climate change.

Impacts of wildfires in aquatic organisms: biomarker responses and erythrocyte nuclear abnormalities in Gambusia holbrooki exposed in situ.

Wildfires are an environmental concern due to the loss of forest area and biodiversity, but also because their role as drivers of freshwater systems contamination by metals. In this context, the fish Gambusia holbrooki was used as a model, deployed for in situ exposure in watercourses standing within a recently burnt area and further assessment of toxic effects. The fish were exposed during 4 days at four different sites: one upstream and another downstream the burnt area and two within the burnt area. Biochemical biomarkers for oxidative stress and damage were assessed. The extent of lipoperoxidative damage was monitored by quantifying malondialdehyde and DNA damage evaluated through erythrocyte nuclear abnormalities observation. Chemical analysis revealed higher metal levels within the burnt area, and exposed fish consistently showed pro-oxidative responses therein, particularly an increase of gill glutathione peroxidase and glutathione reductase activity, the records doubling compared to samples from sites in the unburnt area; also the activity of glutathione-S-transferases comparatively increased (by 2-fold in the liver) in samples from the burnt area, and malondialdehyde was produced twice as much therein and in samples downstream the burnt area reflecting oxidative damage. Consistently, the frequency of erythrocyte nuclear abnormalities was higher at sites within and downstream the burnt area. This study supports the use of sensitive oxidative stress and genotoxicity biomarkers for an early detection of potentially noxious ecological effects of wildfires runoff.

Assessment of properties of vegetation phenology in fire-affected areas from 2000 to 2015in the Peloponnese, Greece

Fire events are among the natural disasters that affect both ecosystem functioning but also human lives. The present work deals with the assessment of the properties of vegetation phenology in areas affected by fire events during a 10-year period in the Peloponnese, Greece. The main objective is to identify special patterns in NDVI time series of fire-affected areas, that can be used either as precursory indicators or as a tool for assessment of regeneration patterns. Therefore, we constructed and analyzed time series of remotely sensed Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI at 250 m spatial resolution with a 16-day time step for affected and non-affected areas surrounding the burnt sites, where the majority of the area refers to the same land cover type. Analysis of changes of NDVI time series of both burnt and unburnt areas was conducted and results indicated that all fire events in the burnt sites caused breaks in the NDVI time series, demonstrated either as NDVI shifts to the lower and/or as changes in the trend and seasonality of the time series. Trends of the NDVI time series of the affected sites were almost doubled in the post fire period compared to the period before the event, indicating the evolution of the regenerating process. The basic statistics of the NDVI time series of the affected and non-affected areas correspond to greater minimum NDVI values of the affected areas throughout the study period, except of the two years after the fire event. Mean NDVI values were almost equal in burnt and unburnt areas before the events and reached the same values approximately seven years after the fire. Maximum NDVI values of the affected and non-affected sites were almost equal before the event but were abruptly reduced in the affected areas after the events and revert to their original state approximately ten years after. An alarming finding is the considerably lower standard deviation of the fire affected areas in comparison to non-fire-affected ones, during all years of the study period, except of a short period immediately after the fire event. It seems thus that areas covered by homogeneous vegetation with no fire breaks or other landforms to act as barriers to fire are the most vulnerable and most severely affected.

Effects of Fire on the Organic and Chemical Properties of Soil in a Pinus halepensis Mill. Forest in Rocallaura, NE Spain

The present study was conducted following a fire that took place in Rocallaura (NE Iberian Peninsula) in 23 June 2016 with the aim of analyzing the chemical properties of soil in burnt and unburnt areas in order to determine the short-term effects of fire on an ecosystem dominated by Pinus halepensis Mill. Transects were laid out in a control area and an adjacent burnt area. Laboratory analyses were performed to determine the chemical properties of the organic and mineral soil layers at 5 cm and 10 cm (total carbon, total nitrogen, organic and inorganic carbon, carbonates, pH, electrical conductivity, and major cations). The results show partial combustion of the organic substrate, with a significant increase in TC, OC, TN, EC and K+, and a slight decrease in pH in the post-fire area compared to the control area, demonstrating that the fire was of low intensity and did not generate significant short-term negative impacts on the soil. Soils of this type, with high organic matter content, tend to maintain their structure after a low-intensity fire and retain the nutrients necessary for ecosystem recovery and resilience.

Ранні наслідки впливу лісової пожежі на різноманітність грибних угруповань соснових лісів Лівобережної України з особливим акцентом на мікоризних грибах

Forest fires constitute widespread and potentially destructive disturbances in forest ecosystems, particularly negative impact on soil mycorrhizal fungi which are major players of the belowground plant. This study investigated the short-term effects of wildfire on fungal communities in Left-Bank Ukraine with special emphasis on mycorrhizal fungi. During the fourteen months after autumn wildfire, fruiting bodies found in the plots were identified, and their mycological richness, diversity and production in both burned and unburnt areas were measured. Total fungal diversity decreased in burned plots, where fungal richness and diversity of mycorrhizal species were significantly lower. Our results also confirmed the data on a rather destructive influence of post-fire forest management on fungal diversity. Only three mycorrhizal fungi associated with Pinus sylvestris L. were common to both sites while pyrophilic species were in close association with burned sites.
 3 Figs., 1 Table, 31 Refs.
 Key words: mycorrhiza, pine plantation, post-fire erosion, wildfire.

Effect of fuel spatial resolution on predictive wildfire models

Computational models of wildfires are necessary for operational prediction and risk assessment. These models require accurate spatial fuel data and remote sensing techniques have ability to provide high spatial resolution raster data for landscapes. We modelled a series of fires to understand and quantify the impact of the spatial resolution of fuel data on the behaviour of fire predictive model. Airborne laser scanning data was used to derive canopy height models and percentage cover grids at spatial resolutions ranging from 2 m to 50 m for Mallee heath fire spread model. The shape, unburnt area within the fire extent and extent of fire areas were compared over time. These model outputs were strongly affected by the spatial resolution of input data when the length scale of the fuel data is smaller than connectivity length scale of the fuel. At higher spatial resolutions breaks in the fuel were well resolved often resulting in a significant reduction in the predicted size of the fire. Our findings provide information for practitioners for wildfire modelling where local features may be important, such as operational predictions incorporating fire and fuel breaks, and risk modelling of peri-urban edges or assessment of potential fuel reduction mitigations.

Mammal responses to moderate-intensity planned burning in a small, isolated woodland reserve

Abstract Context Fire management advice for fauna conservation in protected areas must often be based on expert opinion and extrapolation from very few scientific studies. More monitoring and research are needed to better inform land managers tasked with both managing for biodiversity and managing the threat of bushfires. Aims To document changes in the activity of native and introduced mammal species in response to planned burns in a small, isolated woodland reserve in Tasmania. Methods Over a 10-year period, mammal activity was monitored before and after two separate moderate-intensity planned burns in 20-ha management blocks and in unburnt blocks of similar size by using live-trapping and camera-trapping. Vegetation density was monitored concurrently, and we also searched burnt areas for animals killed by fire. Key results The activity of most mammal populations was largely unaffected by the two planned burns. However, during one of the burns, over 20 rufous-bellied pademelons were directly killed as a result of a need to conduct a backburn. The population recovered after 3 years. The activity of red-necked wallabies, common brushtail possums and short-beaked echidnas generally increased across the whole study area during the 10-year monitoring period. Limited evidence suggests that eastern barred bandicoot and European rabbit activity increased after fire. No swamp rat activity was recorded in burnt areas following the planned burns. Unexpectedly they did not recolonise burnt areas and also ceased to be active in control areas for the last 3 years of the study; we hypothesise that this may be due to the increased dryness and thinning of vegetation. Conclusions We found that most of the mammal populations within this small, isolated reserve were resilient to the planned burning program, with no or limited short-term effect for all but one species. The absence of swamp rats from burnt or unburnt areas for the last 3 years of our study suggests that factors other than fire are also affecting this species. Implications Planned burning is an important tool for biodiversity conservation, but its use needs to be underpinned by empirical data because mammal fire responses are likely to be site-, time- and context-specific.

Complex causes and consequences of rangeland greening in South America – multiple interacting natural and anthropogenic drivers and simultaneous ecosystem degradation and recovery trends

Land-surface greening has been reported globally over the past decades. While often seen to represent ecosystem recovery, the impacts on biodiversity and society can also be negative. Greening has been widely reported from rangelands, where drivers and processes are complex due to its high environmental heterogeneity and societal dynamics. Here, we assess the complexity behind greening and assess its links to various drivers in an iconic, heterogeneous rangeland area, the Iberá Wetlands and surroundings, in Argentina. Time-series satellite imagery over the past 19 years showed overall net greening, but also substantial local browning both in protected and unprotected areas, linking to land use, temporal changes in surface water, fire, and weather. We found substantial woody expansion mainly in the unprotected land, with 37% contributed by tree plantations and the remaining 63% by spontaneous woody expansion, along with widespread transitions from terrestrial land to seasonal surface water. Fire occurrences tended to reduce greening with unprotected areas experiencing widespread and frequent fire. However, protected areas had more browning in unburnt areas than burned areas. Temporal variation in annual precipitation and temperature tended to nonlinearly influence fire occurrences with an interplay of human fire management, further shaping the vegetation greening, pointing to high complexity behind the observed rangeland greening involving interactions among local drivers. Our findings highlight that the observed overall greening is an outcome of multiple trends with clear negative impacts on biodiversity and the local livestock-oriented culture (notably expanding tree plantations) and spontaneous vegetation dynamics, partly involving spontaneous woody expansion. The latter has positive potential for biodiversity and ecosystem services in terms of woodland recovery, but can become negative in such a natural savanna region if expansions develop on a too broad scale, highlighting the importance of ensuring recovery of natural fire and herbivory regimes in protected areas along with sustainable rangeland management elsewhere.

POST-FIRE HAZARD DETECTION USING ALOS-2 RADAR AND LANDSAT-8 OPTICAL IMAGERY

Abstract. This study investigates the use of Advanced Land Observing Satellite 2 (ALOS-2) equipped with an enhanced L-band SAR sensor imagery alongside with Landsat-8 optical sensor in detection and mapping of burnt and unburnt scars occurring after a bushfire in Victoria, Australia. The bushfires had recently occurred in the period of 2018–2019. The analysis was explored using a contextual classifier Support Vector Machine (SVM), as SVM allows us to integrate spectral information and spatial context through the optimal smoothing parameter without degrading image quality. The training and test set datasets consisting of burnt and unburnt pixels were created from Landsat-8 scenes used as reference data. The backscatter intensity maps (acquired before and after the forest fires) from ALOS-2 data were compared and investigated, with a special concern on topographic influence removal. The dual polarizations (HH and HV) have been used to improve the forest fire mapping capability. These change detection techniques were based on image feature differences, index calculation such as normalized burn ratio. The burnt area and unburnt area were then classified via a threshold given by the pre- and post- disaster differences. The classification result achieved an accuracy of 80% Landsat-8 and 89% ALOS-2. This result shows the limitations of burnt area mapping with ALOS-2 due to effect local incidence angle and topography were of greater impact resulting in shadows. Nevertheless, the results in both areas verify the use of satellite SAR sensors and optical in forestry application.

The role of non-equilibrium plasma kinetic effect on GCH4/GOX rocket engine combustion performance

Non-equilibrium plasma has significant chemical kinetic effect and aerodynamic effect, both of which play an important role in the plasma-assisted combustion. In this paper, the numerical study on plasma-assisted combustion in gaseous methane rocket engine is carried out to investigate the impact of kinetic effect on its combustion performance. There are three schemes of plasma excitation via oxygen, methane and both of them in the numerical simulation model. The variations of combustion chamber temperature, pressure, species concentration and special impulse with different dissociation degrees are analysed in three discharge schemes. The results show that non-equilibrium plasma can effectively increase methane burning rate, shorten unburnt area upstream of combustion chamber, and increase the width of combustion zone in shear layer upstream of combustion chamber. And this phenomenon becomes more obvious with the increase of excitation intensity. In addition, more methane and oxygen are added to the combustion process under plasma actuation, and the mole fraction of water is increased in combustion products. The specific impulse of engine is also increased under plasma actuation. At the same degree of dissociation, the combustion-supporting effect of simultaneous discharge of oxygen and methane is significantly greater than that of any component discharge. And in the condition of single component discharge, the combustion-supporting effect of methane is better than that of oxygen.

Hydrological resilience to forest fire in the subarctic Canadian shield

AbstractUnderstanding the role of forest fires on water budgets of subarctic Precambrian Shield catchments is important because of growing evidence that fire activity is increasing. Most research has focused on assessing impacts on individual landscape units, so it is unclear how changes manifest at the catchment scale enough to alter water budgets. The objective of this study was to determine the water budget impact of a forest fire that partially burned a ~450 km2subarctic Precambrian Shield basin. Water budget components were measured in a pair of catchments: one burnt and another unburnt. Burnt and unburnt areas had comparable net radiation, but thaw was deeper in burned areas. There were deeper snow packs in burns. Differences in streamflow between the catchments were within measurement uncertainty. Enhanced winter streamflow from the burned watershed was evident by icing growth at the streamflow gauge location, which was not observed in the unburned catchment. Wintertime water chemistry was also clearly elevated in dissolved organics, and organic‐associated nutrients. Application of a framework to assess hydrological resilience of watersheds to wildfire reveal that watersheds with both high bedrock and open water fractions are more resilient to hydrological change after fire in the subarctic shield, and resilience decreases with increasingly climatically wet conditions. This suggests significant changes in runoff magnitude, timing and water chemistry of many Shield catchments following wildfire depend on pre‐fire land cover distribution, the extent of the wildfire and climatic conditions that follow the fire.

Impact of 2019-2020 mega-fires on Australian fauna habitat.

Australia's 2019-2020 mega-fires were exacerbated by drought, anthropogenic climate change and existing land-use management. Here, using a combination of remotely sensed data and species distribution models, we found these fires burnt ~97,000 km2 of vegetation across southern and eastern Australia, which is considered habitat for 832 species of native vertebrate fauna. Seventy taxa had a substantial proportion (>30%) of habitat impacted; 21 of these were already listed as threatened with extinction. To avoid further species declines, Australia must urgently reassess the extinction vulnerability of fire-impacted species and assist the recovery of populations in both burnt and unburnt areas. Population recovery requires multipronged strategies aimed at ameliorating current and fire-induced threats, including proactively protecting unburnt habitats.

Comparative study of collembola community on burnt forest areas and unburn forest areas in ijen crater nature park Banyuwangi

Forest fire is one of the most crucial environmental and forestry issues in Indonesia. Forest fires are also frequent in the Ijen Crater Nature Park. Forest fires cause loss of filter and humus which is source of food for soil animals. One of the soil animals that inhabit litter and soil is Collembola. This study aims to compare Collembola community in bunt and unburnt areas of Ijen Crater Nature Park. As well as to know the relation of abiotic factors with diversity, evennes, and richness of Collembola in burnt and unburnt areas. This research is a descriptive explorative research. Data retrieval is done with line transect method. The result showed that Collembola index value on burnt and unburnt areas are significantly different. The dominant species in the burnt area is Onychiurus sp, whereas in the unburnt area is Isotomurus sp. The result of abiotic factor regression analysis showed that temperature, humidity and pH level have relation to index of Collembolas diversity, evenness and richness.

New spatial analyses of Australian wildfires highlight the need for new fire, resource, and conservation policies

Extensive and recurrent severe wildfires present complex challenges for policy makers. This is highlighted by extensive wildfires around the globe, ranging from western North America and Europe to the Amazon and Arctic, and, most recently, the 2019-2020 fires in eastern Australia. In many jurisdictions, discussions after significant losses of life, property, and vegetation are sometimes conducted in the absence of nuanced debates about key aspects of climate, land, and resource management policy. Improved insights that have significant implications for policies and management can be derived from spatial and temporal analyses of fires. Here, we demonstrate the importance of such analyses using a case study of large-scale, recurrent severe wildfires over the past two decades in the Australian state of Victoria. We overlaid the location of current and past fires with ecosystem types, land use, and conservation values. Our analyses revealed 1) the large spatial extent of current fires, 2) the extensive and frequent reburning of recently and previously fire-damaged areas, 3) the magnitude of resource loss for industries such as timber and pulplog production, and 4) major impacts on high conservation value areas and biodiversity. These analyses contain evidence to support policy reforms that alter the mode of forest management, target the protection of key natural assets including unburnt areas, manage repeatedly damaged and potentially collapsed ecosystems, and expand the conservation estate. Our mapping approach should have applicability to other environments subject to large-scale fires, although the particular details of policy reforms would be jurisdiction, ecosystem, and context specific.

Forest fire effects on sediment connectivity in headwater sub-catchments: Evaluation of indices performance

Forest fires and post-fire practices influence the hydrological response of the soil in terms of runoff and sediment connectivity (SC). In this study, the ability of four indices (IC-Borselli, IC-Cavalli, IC-Persichillo and aggregated index of connectivity (AIC)) to assess SC was evaluated in three Mediterranean headwater sub-catchments (66, 143 and 194 ha) affected by an arson fire in 2012. Three temporal scenarios (before the fire, one year after the fire and two years after the fire including post-fire practices (salvage logging, skid trails and check dams)) and two computation targets (streams: hillslope–channel SC; and check-dams: hillslope–outlet SC) were considered, obtaining 66 maps of SC at fine spatial resolution (2 m of cell size). Burn severity classes were estimated using Landsat-7 imagery and the dNBR index. The indices' output analysis included geomorphic (landscape units), mathematic (significance, percentiles and frequency distribution), fire (burn severity classes and unburnt areas) and sedimentological (measured specific sediment yield - SSY) criteria. The IC-Borselli and AIC were the most responsive approaches to the effects of fire on SC at catchment scale, whereas the IC-Persichillo was the most sensitive index to the increasing burn severities. The overlay between the fire severities and the geomorphic features appeared as a key aspect to understand the hydrological response at both the stream-system and outlet targets. We found a good and positive agreement between the measured SSY in the three check-dams and the changes in the estimated SCOUTLET due to the fire, especially with the IC-Borselli and AIC. For a better implementation of post-fire programs, we recommend SCOUTLET maps –from AIC– to assess sediment transport in streams, which is dominated by the deposition process, and SCSTREAM maps –from IC-Borselli and AIC– to place sediment control measures at hillslopes for intense rainfall events when effective sediment transport happens.

The impact of fire in palm oil estate on the bird and butterfly species diversity: case study in RAJ Oil Palm Estate, South Sumatera

RAJ oil palm is one of the oil plantation estates in South Sumatera that experienced land fires in 2018 with the burning estimated around 110 ha, and are believed to have a negative impact reducing on species diversity of birds and butterflies in the area. The study was conducted to identify and analyze the comparison of species diversity of birds and butterflies, loss and gain of the species in burnt and unburnt areas after one year of fire. Data collection was carried out in two types of land cover (grass and gelam) in pairs for burnt and unburnt lands after one year of fire. To inventory, the birds and butterfly species were done at the active time of animals, by using strip transect method, parallel in burnt and unburnt areas with a total of 3 repetitions in each type of land cover. The estimation of the impact was obtained by reckoning the loss and gain of birds and butterfly species from the burnt and unburnt area, the level of species richness, evenness, and similarity. The results showed that the total number of animal species found in both observation lines for each type of land cover (grass and gelam) for unburnt and burnt areas were 29 species of birds and 6 species of butterflies. Generally, it can be stated that the values of H and Dmg for birds were relatively greater in the burnt area compared to in the unburnt area. On the contrary, the values for butterflies were greater in the unburnt area than in the burnt area. The percentage of species loss for the bird was smaller than the gain in the burnt area compared to unburnt land, 24% of species loss and 28% of species gain in the grassland, and 14% of species loss and 33% of species gain in the gelam land. For butterflies, the percentage of species loss was relatively greater than the percentage of species gain due to fire, 67% for the species loss and 33% for the species gain.

The impact of fire on herpetofauna species diversity : case study in PT Waimusi Agroindah, Sumatera Selatan

PT Waimusi Agroindah (PT WMA) is one of the oil palm companies that experienced land fires in 2015 with the burning estimated arround 400 ha. This caused PT WMA to be accused of reducing biodiversity in the area. Therefore, this research was conducted to identify the impact of fire on herpetofauna diversity, community similarity and percentage species loss or gain. The observation was done by using visual encounter survey (VES) method in 2017 and 2019 in 2 types area, that is Unburnt (UBA) and post-burnt area (PBA). The result of the study showed that PBA 2017 has the highest of species and individual number, and also richness index (S = 15; N = 61 individuals; Dmg = 3.41). Meanwhile, the similarity index (IS) increased from 0,54 in 2017 to 0.87 in 2019. In addition, the percentage of loss in 2017 was 36.36% to 23.08% in 2019. In addition, the percentage of loss decreased from 36.36% in 2017 to 23.08% in 2019. The impact of a fire is not always negative, this can be seen from the presence of herpetofauna species found in post-burnt areas that are not even found in unburnt areas.

Distribution and abundance of large herbivores in a northern Australian tropical savanna: A multi‐scale approach

AbstractAustralian mammals have exhibited exceptionally high rates of decline since European settlement 230 years ago with much focus on small mammals in northern tropical savannas. In these systems, little scientific attention has been given to the suite of grazing macropods, family Macropodidae, (common wallaroo (Osphranter robustus), antilopine wallaroo (O. antilopinus) and agile wallaby (Notamacropus agilis)). These species may be impacted by feral herbivores and contemporary fire regimes, two threats linked to small mammal declines. A multi‐scale approach using aerial surveys, road surveys and camera trapping was utilised to determine the effects of feral cattle and fire on the distribution and abundance of large macropods in the North Kimberley bioregion. Feral cattle density and biomass exceeded that of macropods regardless of survey technique. Density estimates for cattle were up to 125 times higher (0.3–10.0 km−2) than estimates for macropods (0.08–0.49 km−2). Cattle biomass, based on the aerial survey estimates (corrected for perception bias), were 15 and 95 times higher than macropods for infertile (279 vs. 19 kg km−2) and fertile savannas (518 vs. 5 kg km−2), respectively. Proximity to the nearest pastoral station was a significant predictor of the aerial sightings of feral cattle (P ≤ 0.05). Abundance and foraging activity of cattle were positively associated (P ≤ 0.05) with recently burnt areas. In contrast, camera trapping showed agile wallaby and wallaroo occurrence and foraging were associated with longer unburnt areas (P ≤ 0.05). Agile wallaby and wallaroo were negatively associated with cattle (P ≤ 0.05) and showed substantial diurnal and seasonal separation consistent with an antagonistic interspecific interaction. Results also suggest that the agile wallaby is the primary prey of the dingo, not wallaroo. Collectively, this study suggests that recent landscape changes such as altered fire regimes and introduced herbivores have negatively impacted large grazing macropod species.

Learning-based prediction of wildfire spread with real-time rate of spread measurement

A learning-based wildfire spread model was developed in this study to predict short-term wildfire spread. Real-time rate of spread (RoS) measurement was first conducted by calculating normal movements of fire fronts. Subsequently, machine learning was employed to correlate the local RoS and environmental parameters and predict the RoS in the unburnt area. After that, a narrow-band level-set method was utilized to simulate the evolution of fire front. RoS measurement, machine learning, and level-set method were individually verified with numerically generated fire fronts, and applied in a real scale shrubland fire scenario. Results show that the proposed learning-based method is capable of predicting short-term fire spread without employing an empirical RoS model, which is beneficial for modeling spreading of a real wildfire.