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• Leucosidea sericea is expanding its range and densifying. • This leads to adverse impacts of ecosystem services such as biodiversity and water provisioning. • Runoff-and-run-on dynamics partly modulate the spread of Leucosidea sericea. • Future studies should aim to understand how the distribution of Leucosidea sericea responds to global environmental changes. Rapid woody encroachment by native species is transforming grasslands and savannas across the world. The drivers of this encroachment are diverse, complex, and potentially interlinked, including fire exclusion, overgrazing, plant-plant interactions, extirpation of local mega-fauna, carbon fertilisation, and global warming. In southern Africa, woody encroachment is a well-studied phenomenon that has primarily been documented in savanna and woodland systems, but there has been little work on woody encroachment in southern African mountain systems. These host much of the region's exceptional endemism and provide most of the region's water, and bush encroachment may have serious impacts on both. Leucosidea sericea Eckl. & Zeyh., is a Rosaceous shrub-tree endemic to the eastern Great Escarpment (Sneeuberg, South Africa, to Nyanga, Zimbabwe) that is believed to be rapidly expanding and densifying, however, there is very limited research on this species. Accordingly, we provide the first comprehensive review of the autecology of the species, outlining a summary of past research, and highlighting research needs related to encroachment, impact, and management. In addition, we demonstrate the potential for using repeat photography to study L. sericea ecology, confirming encroachment at some sites and highlighting how run-off-run-on dynamics may influence L. sericea establishment success. Future research on: (a) how the distribution and local density of L. sericea is responding to fire regimes, climate change and recent land-use changes, (b) water use of L. sericea to predict the potential impact of the species on water provisioning at the landscape scale, (c) insect herbivory release on L. sericea due to global warming, (d) changing farming practices and restoring Southern Eland population as the original large mammal that controlled L. sericea, s hould be a priority to guide the management of L. sericea. [ABSTRACT FROM AUTHOR]

Excluding invasive grasses is a significant challenge for neotropical savanna restoration. Invasive grasses alter fire regimes with feedbacks on soil nutrient pools, favoring their own dominance over native species. Here we combine remote sensing with an opportunistic experiment to monitor a savanna under restoration before and after a large natural fire. We measured vegetation and soil fertility in a 4‐year‐old restoration area in Central Brazil, which was subsequently hit by a lightning fire. The restoration area was originally utilized as pasture, dominated by invasive grasses. Over the restoration period, native fast‐growing grasses replaced the invasive species. Within the first year after the fire, we found that the fire had reduced aboveground biomass, species diversity, and abundance of native species with acquisitive resource‐use strategies. Soil phosphorus and pH increased after the fire and favored the re‐invasion of exotic grass species. Our findings suggest that fire occurrence early in the restoration process may trigger exotic grass re‐invasion driven by soil nutrient enrichment. To diminish the re‐invasion risk from exotic grasses in savannas undergoing restoration, managers should beware of the early fire or manage soil fertility after fire events. Successful restoration may also benefit by incorporating native species with high post‐fire recovery capacity. [ABSTRACT FROM AUTHOR]

Background and aims: Arbuscular mycorrhizal (AM) fungi are common mutualists in grassland and savanna systems that are adapted to recurrent fire disturbance. This long-term adaptation to fire means that AM fungi display disturbance associated traits which should be useful for understanding environmental and seasonal effects on AM fungal community assembly. Methods: In this work, we evaluated how fire effects on AM fungal spore traits and community composition vary with fire season (Fall vs. Spring) and time since fire. We tested this by analyzing AM fungal spore traits (e.g., colorimetric, sporulation, and size) from a fire regime experiment. Results: Immediately following Fall and Spring fires, spore pigmentation darkened (became less hyaline); however, this trait response was not linked to fire driven changes in spore community composition and likely implies a plastic spore pigmentation response to fire. Six months after Fall fires, spores in burned plots were lower in volume, produced less color rich pigment, and had higher sporulation rates, and these differences in spore traits were associated with shifts in AM fungal spore communities demonstrating environmental filtering. Conclusion: Fire drove plastic and longer-term changes in AM fungal spore traits and community assembly that varied with fire season (stronger effects in Fall) and time since fire. This demonstrates the utility of applying trait-based approaches to microbial community assembly, and the importance of considering changes in community assembly across time. [ABSTRACT FROM AUTHOR]

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• Northern and eastern grassland-savanna boundary defined by minimum temperature. • Dynamics of fire, frost and growing season temperatures combine to produce this limit. • Western limit is related to moisture availability. • Modern, high-resolution climate data enables refinement of bioclimatic limits. • Reparameterisation improves global model performance at regional scale. Understanding the controls of biome distributions is crucial for assessing terrestrial ecosystem functioning and its response to climate change. We analysed to what extent differences in climate factors (minimum temperatures, water availability, and growing season temperatures (degree days above 5 °C (GDD5)) might explain the poorly understood borders between grasslands, savannas and shrublands in eastern South Africa. The results were used to improve bioclimatic limits in the dynamic global vegetation model (DGVM) LPJ-GUESS. The vegetation model was also used to explore the role of fire in the biome borders. Results show no clear differences between the adjacent biomes in water availability. Treeless grasslands primarily occur in areas with minimum temperatures and GDD5 values below that of savannas. The standard fire module in LPJ-GUESS is not able to reproduce observed burned area patterns in the study region, but simulations with prescribed fire return intervals show that a combination of low temperatures and fire can explain the treeless state of the grassland biome. These results confirm earlier hypotheses that a combination of low winter temperatures, causing frost damage to trees, and low growing season temperatures that impede tree sapling growth and recruitment, particularly under re-occurring fires, drive the grassland-savanna border. With these insights implemented, the LPJ-GUESS simulation results substantially improved grass distribution in the grassland biome, but challenges remain concerning the grassland-shrubland boundary, tree-grass competition and prognostic fire modelling. [ABSTRACT FROM AUTHOR]

Indigenous communities throughout California, USA, are increasingly advocating for and practicing cultural fire stewardship, leading to a host of social, cultural, and ecological benefits. Simultaneously, state agencies are recognizing the importance of controlled burning and cultural fire as a means of reducing the risk of severe wildfire while benefiting fire‐adapted ecosystems. However, much of the current research on the impacts of controlled burning ignores the cultural importance of these ecosystems, and risks further marginalizing Indigenous knowledge systems. Our work adds a critical Indigenous perspective to the study of controlled burning in California's unique coastal grasslands, one of the most biodiverse and endangered ecosystems in the country. In this study, we partnered with the Amah Mutsun Tribal Band to investigate how the abundance and occurrence of shrubs, cultural plants, and invasive plants differed among three adjacent coastal grasslands with varying fire histories. These three sites are emblematic of the state's diverging approaches to grassland management: fire suppression, fire suppression followed by wildfire, and an exceedingly rare example of a grassland that has been repeatedly burned approximately every 2 years for more than 30 years. We found that Danthonia californica was significantly more abundant on the burned sites, whereas all included shrub species (Baccharis pilularis, Frangula californica, and Rubus ursinus) were significantly more abundant on the site with no recorded fire, results that have important implications for future cultural revitalization efforts and the loss of coastal grasslands to shrub encroachment. In addition to conducting a culturally relevant vegetation survey, we used Sentinel‐2 satellite imagery to compare the relative severities of the two most recent fire events within the study area. Critically, we used interviews with Amah Mutsun tribal members to contextualize the results of our vegetation survey and remote sensing analysis, and to investigate how cultural burning contrasts from typical Western fire management approaches in this region. Our study is a novel example of how interviews, field data, and satellite imagery can be combined to gain a deeper ecological and cultural understanding of fire in California's endangered coastal grasslands. [ABSTRACT FROM AUTHOR]

Satellite detection of active fires has contributed to advance our understanding of fire ecology, fire and climate dynamics, fire emissions, and how to better manage the use of fires as a tool. In this study, we use active fire data of 12 years (2012-2023) combined with landcover information in the South-Central United States to derive a monthly, open-access dataset of categorized fires. This is done by calculating a fire predominance index used to rank fire-prone landcovers, which are then grouped into four main landscapes: grassland, forest, wildland, and crop fires. County-level aggregated analyses reveal spatial distributions, climatologies, and peak fire months that are particular to each fire type. Using the Standardized Precipitation Index (SPI), it was found that during the climatological fire peak-month, the SPI and fires exhibit an inverse relationship in forests and crops, whereas grassland and wildland fires show less consistent inverse or even direct relationship with the SPI. This varied behavior is discussed in the context of landscapes' responses to anomalies in precipitation and fire management practices, such as prescribed fires and crop residue burning. In a case study of Osage County (OK), we find that large wildfires, known to be closely related to climate anomalies, occur where forest fires are located in the county and absent in areas of grassland fires. Weaker grassland fire response to precipitation anomalies can be attributed to the use of prescribed burning, which is normally planned under environmental conditions that facilitate control and thus avoided during droughts. Crop fires, on the other hand, are set to efficiently burn residue and are practiced more intensely in drier years than in wetter years, explaining the consistently strong inverse correlation between fires and precipitation anomalies. In our increasingly volatile climate, understanding how fires, vegetation, and precipitation interact has become imperative to prevent hazardous fire conflagrations and to better manage ecosystems. [ABSTRACT FROM AUTHOR]

This study assessed the spatio-temporal variation of the degree of curing (DoC) in the Golden Gate Highlands National Park (GGHNP) from 2016 to 2020. The estimation of the degree of grass curing was carried out with the high spatial resolution fused remotely sensed data of MODIS and Sentinel-2 employing Index-then-Blend (IB) data fusion methods on Google Earth Engine (GEE) to compute Grassland Curing Index (GCI) using soil and vegetation moisture content indices-based grassland curing algorithm. Grassland curing indices were computed on Google Earth Engine and converted into Grassland Curing Maps (GCMs), which were then synthesized into fire danger maps. The study showed that all selected indices have the highest DoC in the month of September, with the minor time variation observed in MODIS and Sentinel 2-derived GCI estimated using Shortwave Infrared Water Stress (GCI_SIWSI) in the months of August and March, respectively. The analysis further revealed that GCI_SIWSI (44%) derived from Sentinel-2 data yielded the highest area of extremely high fire danger, followed by GCI estimated using Normalized Difference Moisture Index (GCI_NDMI) (25%) derived from fused data, MODIS-derived GCI_SIWSI and fused-derived GCI estimated using Global Vegetation Monitoring Index (GCI_GVMI) (both 16%). The GCI_SIWSI derived from Sentinel-2 data also showed that more than 95% of the entire landmass of the study area was within a high to extremely high fire danger zone, making the park's vegetation susceptible to fire. Among all the four selected indices correlated against fire point, only SIWSI revealed a positive relationship across MODIS, Sentinel-2 and Fused data. It is also evident from the study that GCMs derived from Fused data outperformed MODIS and Sentinel-2 with the highest R2 and F values of 0.65 and 380, respectively. These results indicate that GCI derived from fused remotely sensed data is a promising GCI for accurately assessing the DoC over mountainous grassland environments. The study paved the way for increasing the spatial resolution for estimating the DoC for fire and fuel management of parks and other fire agencies within mountainous grassland environments. [ABSTRACT FROM AUTHOR]

Despite the importance of South Africa's Afromontane grasslands for ecosystem services (water supply and biodiversity), soil organic carbon (SOC) research remains limited. These grasslands evolved with fire, and fire exclusion leads to native plant afforestation. This study investigated SOC fractions and origin to understand the impact of fire‐exclusion‐driven afforestation and aspect on SOC storage in Afromontane grasslands. This study in Cathedral Peak Research Catchments, initiated in the 1940s, compared an afforested fire‐excluded site (AF) to a periodically burnt (accidental fires, 2–5 years interval) grassland (PB) within the same catchment (Catchment‐IX). Additionally, it compared a south‐facing periodically burnt grassland (Catchment‐IX) to a north‐facing biennially burnt grassland (Catchment‐VI). Soil samples collected at soil‐depth increments (0–5, 5–10, 10–15, 15–20, 20–30, 30–60 and 60–100 cm) revealed that, within Catchment IX, PB had more topsoil SOC stocks and microbial activity than AF but similar active carbon (C) concentrations. As expected, δ13C values revealed that SOC in PB originates from C4 grasses, whilst it mostly originates from C3 plants in AF. The south‐facing slope (Catchment‐IX) had more SOC stocks, microbial activity and active C compared to the north‐facing slope (Catchment‐VI). Fire‐exclusion‐driven afforestation changed SOC input from roots to litter, thus reducing SOC storage. Cooler south‐facing slopes are better C reservoirs. Afromontane grasslands show greater potential for C sequestration than afforested systems. [ABSTRACT FROM AUTHOR]

As a result of the advocacy of Indigenous communities and increasing evidence of the ecological importance of fire, California has invested in the restoration of intentional burning (the practice of deliberately lighting low-severity fires) in an effort to reduce the occurrence and severity of wildfires. Recognizing the growing need to monitor the impacts of these smaller, low-severity fires, we leveraged Sentinel-2 imagery to reveal important inter- and intra-annual variation in grasslands before and after fires. Specifically, we explored three methodological approaches: (1) the complete time series of the normalized burn ratio (NBR), (2) annual summary metrics (mean, fifth percentile, and amplitude of NBR), and (3) maps depicting spatial patterns in these annual NBR metrics before and after fire. We also used a classification of pre-fire vegetation to stratify these analyses by three dominant vegetation cover types (grasses, shrubs, and trees). We applied these methods to a unique study area in which three adjacent grasslands had diverging fire histories and showed how grassland recovery from a low-severity intentional burn and a high-severity wildfire differed both from each other and from a reference site with no recent fire. On the low-severity intentional burn site, our results showed that the annual NBR metrics recovered to pre-fire values within one year, and that regular intentional burning on the site was promoting greater annual growth of both grass and shrub species, even in the third growing season following a burn. In the case of the high-severity wildfire, our metrics indicated that this grassland had not returned to its pre-fire phenological signals in at least three years after the fire, indicating that it may be undergoing a longer recovery or an ecological shift. These proposed methods address a growing need to study the effects of small, intentional burns in low-biomass ecosystems such as grasslands, which are an essential part of mitigating wildfires. [ABSTRACT FROM AUTHOR]

Exotic annual grass invasion is a widespread threat to the integrity of sagebrush ecosystems in Western North America. Although many predictors of annual grass prevalence and native perennial vegetation have been identified, there remains substantial uncertainty about how regional‐scale and local‐scale predictors interact to determine vegetation heterogeneity, and how associations between vegetation and cattle grazing vary with environmental context. Here, we conducted a regionally extensive, one‐season field survey across burned and unburned, grazed, public lands in Oregon and Idaho, with plots stratified by aspect and distance to water within pastures to capture variation in environmental context and grazing intensity. We analyzed regional‐scale and local‐scale patterns of annual grass, perennial grass, and shrub cover, and examined to what extent plot‐level variation was contingent on pasture‐level predictions of site favorability. Annual grasses were widespread at burned and unburned sites alike, contrary to assumptions of annual grasses depending on fire, and more common at lower elevations and higher temperatures regionally, as well as on warmer slopes locally. Pasture‐level grazing pressure interacted with temperature such that annual grass cover was associated positively with grazing pressure at higher temperatures but associated negatively with grazing pressure at lower temperatures. This suggests that pasture‐level temperature and grazing relationships with annual grass abundance are complex and context dependent, although the causality of this relationship deserves further examination. At the plot‐level within pastures, annual grass cover did not vary with grazing metrics, but perennial cover did; perennial grasses, for example, had lower cover closer to water sources, but higher cover at higher dung counts within a pasture, suggesting contrasting interpretations of these two grazing proxies. Importantly for predictions of ecosystem response to temperature change, we found that pasture‐level and plot‐level favorability interacted: perennial grasses had a higher plot‐level cover on cooler slopes, and this difference across topography was starkest in pastures that were less favorable for perennial grasses regionally. Understanding the mechanisms behind cross‐scale interactions and contingent responses of vegetation to grazing in these increasingly invaded ecosystems will be critical to land management in a changing world. [ABSTRACT FROM AUTHOR]

The dry weight of biomass to be consumed by fire in the wildland – urban interface (WUI) plays an important role in the spread of fire inside the WUI. In this paper, we present a model of grassland fire spread based on fuel load. The herbaceous stratum is represented by a heterogeneous fuel layer, with characteristics close to the real one. Fire propagation is simulated by using a two-phase model. Thirteen fire experiments in eastern Australia were used to test the predictive capacity of the model. The rates of spread are on the whole relatively well predicted. Using the fuel layer model to simulate fire spread, we tested how fuel load affects fire behavior. The results show that the fire spread rate does not systematically decrease with the increasing of fuel load. However, there may be a critical fuel load for rapid rate of spread, below or above which the rate of spread decreases. [ABSTRACT FROM AUTHOR]

Fire occurrence has been increasing in the high Andean grasslands due to the presence of highly flammable elements and climate change. Understanding the effects of the fires is crucial for the conservation of these ecosystems. This study aimed to determine the effects of fires on the composition, diversity, fruiting of plant species, and physicochemical characteristics of soils in high Andean grasslands over two post-fire growing seasons. We assessed ten fires, five of which occurred in 2023 (one post-fire growing season) and the other five in 2022 (two post-fire growing seasons). Ten transects were established at each study site, five in burned areas and five in unburned areas. Species composition differed between burned and unburned areas across both post-fire growing seasons. Species diversity and evenness were higher in the burned areas compared to unburned areas after two post-fire growing seasons. In both post-fire growing seasons, dry mass was higher in unburned areas than in burned areas. Herbs showed a higher percentage of individuals in the reproductive stage in burned areas, but only after one post-fire growing season. In contrast, the presence of woody individuals with reproductive structures was higher in unburned areas across both post-fire growing seasons. Regarding soils, only some parameters (organic matter, Na+, CEC, pH, available P, and K+) were affected by fires, and the direction of these changes varied between ∼ 6 months and ∼ 18 months post-fires. Our study suggests that fire severity in this type of ecosystem is low, as most soil parameters were not significantly affected. The burning of grasses may lead to increased diversity, particularly due to the enhanced fruiting of herb species. However, the recovery of woody species and biomass requires more time, which is perceived negatively by the local population.

Accurate comprehension of grassland fires is imperative for maintaining ecological stability. In this study, we propose a novel fire model that incorporates real-time meteorological conditions. Our methodology integrates key meteorological factors including relative humidity, temperature, degree of solidification of combustible materials, and wind speed. These factors are embedded into a comprehensive function that determines both the downwind and upwind spreading speeds of the fire. Additionally, the model accommodates fire spread in the absence of wind by incorporating the direction perpendicular to the wind, with wind speed set to zero. By precisely determining wind speed, the model enables real-time calculation of fire spread speeds in all directions. Under stable wind conditions, the fire spread area typically adopts an elliptical shape. Leveraging ellipse properties, we define the aspect ratio as a function related to wind speed. Consequently, with knowledge of the fire duration, the model accurately estimates the area of fire spread. Our findings demonstrate the effectiveness of this model in predicting and evaluating fires in the Hulunbuir Grassland. The model offers an innovative method for quantifying grassland fires, contributing significantly to the understanding and management of grassland ecosystems. [ABSTRACT FROM AUTHOR]

Background: In 1986, CSIRO conducted a large program of experimental fires in grassland at Annaburroo Station, Northern Territory, Australia, with the objective of quantifying the effect of fuel condition (load and height) on fire behaviour. Aims: This paper provides the data collected during this program, representing a unique set of observations and measurements of large, free-burning experimental fires conducted in a multi-factor experimental design. Methods: Data are collated by experimental burn plot, providing detailed measurements of weather (wind speed, air temperature, relative humidity), fuel state (load, height, moisture content, curing) and fire behaviour (rate of spread, flame depth, flame height, head fire width), as well as processed information (e.g. steady-state rate of spread). Data availability: The data are made available for free download on the CSIRO Data Access Portal () and include detailed metadata descriptions of the data and their structure, also provided in this article. Conclusions: We have made the data available for fire behaviour researchers around the world to use in their research under the Creative Commons Attributions licence. It is hoped they will analyse these data and extract new and innovative insights to help improve our understanding of wildland fires burning in grass fuels. The 1986 Annaburroo grassland fire experiments conducted in the Northern Territory, Australia, created a unique dataset of fire behaviour across a range of fuel and burning conditions. This dataset, comprising detailed observations of fuels, weather and fire behaviour in 121 plots, is now publicly available via the CSIRO Data Access Portal. [ABSTRACT FROM AUTHOR]

Woody encroachment—the spread of woody vegetation in open ecosystems—is a common threat to grasslands worldwide. Reversing encroachment can be exceedingly difficult once shrubs become established, particularly clonal species that resprout following disturbance. Single stressors are unlikely to reverse woody encroachment, but using multiple stressors in tandem could be successful in slowing or reversing encroachment. We explored whether increasing fire frequency in conjunction with multi-year drought could reduce growth and survival of encroaching shrubs in a tallgrass prairie in northeastern Kansas, USA. Passive rainout shelters (~ 50% rainfall reduction) were constructed over mature clonal shrubs (Cornus drummondii) and co-existing C4 grasses in two fire treatments (1-year and 4-year burn frequency). Leaf- and whole-plant level physiological responses to drought and fire frequency were monitored in shrubs and grasses from 2019 to 2022. Shrub biomass and stem density following fire were unaffected by five years of consecutive drought treatment, regardless of fire frequency. The drought treatment had more negative effects on grass leaf water potential and photosynthetic rates compared to shrubs. Shrub photosynthetic rates were remarkably stable across each growing season. Overall, we found that five consecutive years of moderate drought in combination with fire was not sufficient to reduce biomass production or stem density in an encroaching clonal shrub (C. drummondii). These results suggest that moderate but chronic press-drought events do not sufficiently stress encroaching clonal shrubs to negatively impact their resilience following fire events, even when fire frequency is high. [ABSTRACT FROM AUTHOR]

The state of meadow vegetation in areas with different ages of experimental spring burnout (from 1 to 12 years ago) was studied in the Tomsk region for 3 years. On experimental plots of 1 m2 and 100 m2 (small- and middle-scale levels, respectively), the dynamics of species richness, total projective cover of vegetation, and aboveground phytomass reserves were characterized, and the structure of communities was analyzed. It was revealed that a single fire in the spring significantly reduces species richness for small-scale plots and increases the total projective cover for middle-scale plots. Structural differences from control plots can be traced from 1 to 4 years for different characteristics. The effects of fire are more prominent for small-scale plots. To suppress tree growth and maintain the existence of meadows, grass fires seem to be a less effective practice than mowing. At the same time, the results obtained potentially allow us to consider prescribed burning as a tool for maintaining the stability of meadow plant communities in the south of Western Siberia, preventing them from becoming overgrown with tree undergrowth, in cases with a controlled frequency of burning and the use of appropriate fire safety measures. [ABSTRACT FROM AUTHOR]

This study explores the historical occurrence of wetland ecosystems in Greece by using recurring Phragmites australis (common reed) burnings as an indicator. Phragmites australis, a plant closely associated with wetlands, provides excellent insights into wetland distribution. We establish a substantial association between reed fires and historical wetland existence in Greece using geographical and statistical analysis, with these fires exhibiting remarkable constancy across time. Using Corine land-cover (CLC) data, we extend our analysis into land-use dynamics, demonstrating that places with the highest reed-bed-fire rates were originally wetlands, particularly those converted into permanent irrigated land and areas with complex agriculture patterns. We find spatial commonalities between reed fires and past wetland existence by analyzing fire occurrence across three main categories: reed fires, agricultural land fires, and grassland fires. Historical records of wetland conversion into agricultural land (or land reclamation works) in locations such as Yianitsa and Kopaida give context to our findings. Visualizations confirm the clustering of reed fires around these converted agricultural regions. In summary, our study offers a unique indicator based on Phragmites australis burnings that can be used to identify previous wetland-type ecosystems, with Mediterranean-wide implications. Despite data constraints, this study adds to the conversation about wetland preservation and sustainable land-use management. [ABSTRACT FROM AUTHOR]

Background: The Australian Fire Danger Rating System program (AFDRS) has built a new fire danger rating system for Australia. A live trial of the system's Research Prototype (AFDRSRP), based on fire behaviour thresholds, was run and evaluated between October 2017 and March 2018. Aims: Live trial results are critically analysed, and knowledge gaps and recommendations for future work discussed. Methods: Australian bushfire experts assessed wildfires and prescribed burns across a range of vegetation types and weather conditions. Forecast fire danger ratings calculated using: (1) AFDRSRP; and (2) Forest Fire Danger Index (FFDI) and Grassland Fire Danger Index (GFDI) were compared against ratings derived by expert opinion for each evaluation fire (n = 336). Key results: Overall performance of AFDRSRP was superior to the FFDI/GFDI system (56 vs 43% correct), with a tendency to over-predict rather than under-predict fire potential. AFDRSRP also demonstrated its value to assess fire danger in fuel types not conforming to current grassland or forest models; e.g. for fuels that were grouped to use mallee-heath, spinifex and shrubland fire spread models. Conclusions: The AFDRSRP live trial was successful, outperforming the existing operational fire danger system. Implications: Identified improvements would further enhance AFDRSRP performance, ensuring readiness for operational implementation. A Research Prototype of the Australian Fire Danger Rating System (AFDRSRP) was designed and tested in a live trial. Fire danger ratings derived from the AFDRSRP and FFDI/GFDI systems were compared to expert-derived ratings for 336 fires. In this paper the results of the live trial are presented and discussed. This article belongs to the Collection Australian Fire Danger Rating System. [ABSTRACT FROM AUTHOR]

Background: The Australian Fire Danger Rating System (AFDRS) was implemented operationally throughout Australia in September 2022, providing calculation of fire danger forecasts based on peer-reviewed fire behaviour models. The system is modular and allows for ongoing incorporation of new scientific research and improved datasets. Aims: Prior to operational implementation of the AFDRS, a Research Prototype (AFDRSRP), described here, was built to test the input data and systems and evaluate the performance and potential outputs. Methods: Fire spread models were selected and aligned with fuel types in a process that captured bioregional variation in fuel characteristics. National spatial datasets were created to identify fuel types and fire history in alignment with existing spatial weather forecast layers. Key results: The AFDRSRP demonstrated improvements over the McArthur Forest and Grass Fire Danger systems due to its use of improved fire behaviour models, as well as more accurately reflecting the variation in fuels. Conclusions: The system design was robust and allowed for the incorporation of updates to the models and datasets prior to implementation of the AFDRS. A spatially explicit forecast calculation system was designed and implemented to assess a new fire danger rating system for Australia based on fire behaviour models, weather inputs and a national fuel spatial data layer. This article is part of a collection about the Australian Fire Danger Rating System. This article belongs to the Collection Australian Fire Danger Rating System. [ABSTRACT FROM AUTHOR]

Smoke, a byproduct of forest and grassland combustion, holds the key to precise and rapid identification—an essential breakthrough in early wildfire detection, critical for forest and grassland fire monitoring and early warning. To address the scarcity of middle–high-resolution satellite datasets for forest and grassland fire smoke, and the associated challenges in identifying smoke, the CAF_SmokeSEG dataset was constructed for smoke segmentation. The dataset was created based on GF-6 WFV smoke images of forest and grassland fire globally from 2019 to 2022. Then, an optimized segmentation algorithm, GFUNet, was proposed based on the UNet framework. Through comprehensive analysis, including method comparison, module ablation, band combination, and data transferability experiments, this study revealed that GF-6 WFV data effectively represent information related to forest and grassland fire smoke. The CAF_SmokeSEG dataset was found to be valuable for pixel-level smoke segmentation tasks. GFUNet exhibited robust smoke feature learning capability and segmentation stability. It demonstrated clear smoke area delineation, significantly outperforming UNet and other optimized methods, with an F1-Score and Jaccard coefficient of 85.50% and 75.76%, respectively. Additionally, augmenting the common spectral bands with additional bands improved the smoke segmentation accuracy, particularly shorter-wavelength bands like the coastal blue band, outperforming longer-wavelength bands such as the red-edge band. GFUNet was trained on the combination of red, green, blue, and NIR bands from common multispectral sensors. The method showed promising transferability and enabled the segmentation of smoke areas in GF-1 WFV and HJ-2A/B CCD images with comparable spatial resolution and similar bands. The integration of high spatiotemporal multispectral data like GF-6 WFV with the advanced information extraction capabilities of deep learning algorithms effectively meets the practical needs for pixel-level identification of smoke areas in forest and grassland fire scenarios. It shows promise in improving and optimizing existing forest and grassland fire monitoring systems, providing valuable decision-making support for fire monitoring and early warning systems. [ABSTRACT FROM AUTHOR]

Influence of spring grass fires on the properties of the upper humus horizon of migrational–mycellary chernozem (Haplic Chernozem) has been studied by the example of soils at the Basic Experimental Complex, Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences (Tomsk). A total of 56 samples (5–14 replicates) were collected at the plots burned two months ago, 1, 2, 3, and 11 years ago. A considerably high stability of the controlled soil properties (cation–anion composition of water extract, content of grain-size fractions and mobile compounds of a wide range of elements, total C and N, organic carbon, pH value, basicity of ) under pyrogenic impact of spring grass fires has been found. The content of mobile Ca, Mg and Sr, as well as water-soluble Mg2+ and basicity of appear to be informative parameters reflecting a significant pyrogenic impact over the past 11 years. Their content is higher in the soils at recently (0–3 years ago) burnt plots as compared to old-burnt (11 years ago) and unburnt plots. Among the studied parameters, the pH value, the content of mobile Ba and Sr, and the content of grain-size fractions 1–5, 5–10, and 10–50 µm show a low variation coefficient (mainly <20% in all studied subsets of samples); whereas the content of water-soluble ammonium and mobile Li and Zn manifest a high variation coefficient (>70%). [ABSTRACT FROM AUTHOR]

Background: Fireline intensity (I f) quantifies the power of the fireline and is used for various purposes. I f and flame length (L f) are relatable to each other using an empirical power function, which has been considered fuel-specific. Aims: The aim of this study was to develop generic L f − I f relationships based on a robust set of field head fires from the literature (n = 797) conducted worldwide in forest, shrubland and grassland. Methods: L f was determined from the base of the fuel bed for comparability across fires in different fuel heights, and the effect of vegetation type was examined. Key results: Although I f could be approximately described using the same function in forest and shrubland, fires in grassland required different fitted coefficients; we speculate that fuel particles' surface area-to-mass ratio is the main fuel metric influencing flame structure. Conclusions: Fuel-generic relationships for I f are reasonably accurate and encompass the high end of surface fire I f. Previous studies suggested their unviability, most likely because of limitations in the number of observations and data ranges, difficulty in objectively measuring L f and variation in L f definition. Implications: The generic relationships presented in this work will be of interest for research and management purposes when specific models for I f are non-existent. We developed empirical relationships linking fireline intensity and flame length, based on a compilation of data collected in field head fires, conducted worldwide in forest, shrubland and grassland. Two relationships emerged, respectively for forest and shrublands and for grasslands, and were deemed suitable for scientific and operational application. [ABSTRACT FROM AUTHOR]

Human activities in mesic savanna ecosystems have resulted in plant communities that are heavily dominated by fire‐tolerant grass species, are less diverse, and offer fewer ecosystem services such as palatable plant biomass. Experimental studies manipulating fire and grass presence have mostly been conducted in ecosystems invaded by exotic grass species. However, these experiments are also relevant to ecosystems that have become dominated by native grass species due to changes in human activities. Our study compared three different management treatments in the Eastern Ghats of India, where mesic savanna ecosystems are highly dominated by the unpalatable native Cymbopogon grasses, specifically: (1) control (both Cymbopogon grasses and fire are present), (2) fire exclusion, and (3) manual removal of Cymbopogon grasses and fire exclusion. We found that both grass removal and fire exclusion were necessary to significantly increase palatable herbaceous plant biomass and species diversity, and that species diversity responses were only significant at larger spatial grains of investigation. High site‐to‐site variation in the grass removal and fire exclusion treatment prevented us from detecting significant differences in species composition across treatments, even though particular palatable grass species benefited from the treatment. Our study is in line with research from other mesic savanna systems showing that fire management alone is not sufficient to transition ecosystems to a desired or historical state. We demonstrate how normally costly management practices, such as manual removal of dominant grasses, can be reasonably achieved through collaboration between scientists, community governed village institutions, and government and nongovernment agencies in socioecological systems. [ABSTRACT FROM AUTHOR]

Grassland fires and dust weather in Mongolia can trigger major cascading disasters. Grassland fires from autumn to the following spring can indirectly affect dust weather occurrence in the spring by affecting land surface vegetation cover. In this paper, we selected the aimag (province) of Dornod, Mongolia, a typical temperate grassland area, as the study area. The study aims to (1) analyze the spatiotemporal patterns of grassland fire and dust weather in the past 22 years, as well as the effect of grassland fire on dust weather and to (2) explore in depth the mechanisms of the effects of grassland fire on dust weather. To achieve these goals, we utilize high-resolution satellite burned-area data and Synop dust data. In general, grassland fire and dust weather occurrence clearly varied spatiotemporally across the study area. Grassland fires are typically more frequent in spring and autumn, and dust weather is mainly concentrated in spring. Cumulative grassland fires (both days and burned area) from autumn to the following spring affected the spring cumulative dust weather days significantly, especially the spring cumulative dust storm days. Analysis of the mechanism of the effect of grassland fire on dust storms showed that abundant summer precipitation resulted in higher vegetation cover and more accumulated fuel from autumn to April of the following spring. Consequently, the cumulative grassland fire days were higher, and the cumulative burned area was larger during the period, leading to a significant increase in cumulative dust storm days in May of the spring. In Mongolia, grassland fires are often caused by human factors. The findings of the present study could facilitate the crafting of measures to prevent and reduce grassland fires and indirectly minimize dust weather frequency to protect the ecological environment and promote sustainable development. [ABSTRACT FROM AUTHOR]

C4 grasses coevolved with fires, employing specialized adaptive traits to recover from recurrent fires of varying regimes, thereby maintaining plant diversity and plant population stability. However, the knowledge of how C4 bunchgrasses recover from varying fire return intervals (FRIs) is limited. Biomass, tillering, flowering, and growth-related traits of Digitaria eriantha, Themeda triandra, Sporobolus fimbriatus, and Cymbopogon plurinodis were assessed in 0- (unburned), 1-, 2-, and 4-year FRIs, each applied in two 0.5 ± 0.01 ha plots from 1980–2022 at the University of Fort Hare research farm, South Africa. FRIs and grass species interacted significantly on biomass production, crown size, tiller production, and reproductive tillers, with responses varying interspecifically depending on the FRI. Cymbopogon plurinodis attained higher total biomass in 1-year FRI, whereas T. triandra produced relatively low biomass in all FRIs compared to 0-year FRI. Nonetheless, T. triandra attained nearly two to three-fold more tillers per plant and three to five-fold more reproductive tillers in 2- and 4-year FRIs compared to other FRIs. Similarly, S. fimbriatus had two-fold more reproductive tillers in 2-year FRIs compared to 0- and 1-year FRIs. We deduce that C4 bunchgrasses respond differentially under recurrent fires depending on the fire return interval, with 2- and 4-year FRIs promoting vegetative and sexual regeneration by enhancing tillering and flowering. [ABSTRACT FROM AUTHOR]

Background. Fire modulates herbivore dynamics in open ecosystems. While extensive work demonstrates the interaction between fire and vertebrate grazers, less research describes how grasshopper herbivory dynamics respond to fire. Aim. We examined how fire increased grass crude protein content and increased the density of and offtake by grasshoppers relative to unburned mixed-grass prairie. Methods. We deployed grasshopper exclusion cages to determine grasshopper offtake of aboveground plant biomass, counted grasshopper abundance throughout the study period, and measured crude protein content of aboveground grass biomass. Key results. Offtake and density were higher in burned versus unburned plots. Burned plot grasshopper density increased over time, with greater rates of increase in recently burned plots, while density remained constant in unburned locations. Conclusions. We present a potential mechanism by which fire interacts with grasshoppers in open ecosystems. It is likely that greater grasshopper offtake and density in recently-burned plots is at least partially attributable to higher crude protein content, as grass in these plots has a much higher proportion of recent growth after fire removed senesced material. Implications. Grasshopper herbivory likely acts as a multiplier of livestock herbivory in burned rangeland. Restoring fire regimes can balance direct negative effects of heating against nutritional benefits. [ABSTRACT FROM AUTHOR]

The grasslands of North America are threatened by woody encroachment. Restoring historical fire regimes has been used to manage brush encroachment. However, fire management may be insufficient due to the nonlinear and hysteretic responses of vegetation recovery following encroachment and the social–political constraints affecting fire management. We synthesized the fire thresholds required to control woody encroachment by typical encroaching species in North America, especially the Great Plains region, and identified the social–political constraints facing fire management in selected grassland national parks. Our synthesis revealed the resistance, hysteresis, and irreversibility of encroached grasslands using fire and emphasized the need for a combination of brush management methods if the impacts of climate change are to be addressed. Frequent fires alone may maintain grassland states, reflecting resistance. However, high-intensity fires exceeding fire-mortality thresholds are required to exclude non-resprouting shrubs and trees, indicating hysteresis. Fire alone may be insufficient to reverse encroachment by resprouting species, exhibiting reversibility. In practice, appropriate fire management may restore resistant grassland states. However, social–political constraints have restricted the use of frequent and high-intensity fires, thereby reducing the effectiveness of management actions to control woody encroachment of grasslands in national parks. This research proposes a resilience-based framework to manage woody encroachment in grassland national parks and similar protected areas. [ABSTRACT FROM AUTHOR]

In savannas, fire and herbivores are important drivers of natural ecosystem processes. Fire is also used intensively for management purposes. However, reported fire effects differ between studies. Reasons for these differences are still poorly understood. Here, we investigated the effects of fire on leaf chemistry of grasses and woody plants in the savanna of the Busanga Flood Plain, Zambia, in relation to the time elapsed between plant sampling and the last fire (fire age) and the frequency of fires during the last 16 years (fire recurrence). We analyzed leaves for their nitrogen, carbon, and fiber concentrations, and estimated their metabolizable energy content, reflecting feed quality for browsers and grazers. Grasses and woody plants differed in all chemical components and showed different responses to fire. Grass quality was higher at sites burnt in the year of sample collection than at sites burnt only in previous years, but did not change under different fire recurrences. Leaves of woody plants did not differ in relation to fire age but their quality increased with increasing fire recurrence. In woody plants, the carbon content responded to the interaction between fire age and fire recurrence, indicating changes in carbon allocation in response to fire. Thus, burning increased feed quality for grazers and browsers but on different temporal scales. The scale effects may contribute to the differences in resource allocation described by different studies. They merit more attention in management decisions as well as in future studies on fire effects in savanna systems. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Prescribed fires are often used as a management tool in grasslands to promote the growth of desired plant species. These fires also impact other ecological communities where they occur. One ecological community that is often overlooked regarding fire is biological soil crusts (biocrusts). Biocrusts contain an assemblage of cyanobacteria, lichens, and bryophytes living on the soil surface and are important for nutrient cycling and soil stability. Here, we used prescribed burns in a California coastal grassland on San Clemente Island (SCI) to understand how fire impacts biocrust cover. Two sites were burned in a prescribed fire in 2012 and then again in 2017, and one site was burned in a wildfire in 2012 and a prescribed fire in 2017. We compared the percent cover of biocrusts in the burned and unburned plots in 2018 and 2019. However, precipitation differed drastically between sampling years; therefore, we also assessed the role of precipitation in moderating biocrust cover in the burned and unburned plots. In 2018 and 2019, one and two years after the last prescribed fire, the burned plots had more cyanobacterial biocrust cover than the controls. Annual precipitation had a negative effect on cyanobacterial biocrust cover, though lichen- and bryophyte-dominated biocrusts increased with increasing precipitation. The abundance of cyanobacterial biocrusts in the burned plots suggests either a level of recovery after the fire or the ability of biocrusts to withstand a grassland fire, though the effect is mediated by precipitation. [ABSTRACT FROM AUTHOR]

Developing models for predicting the rate of fire spread (ROS) in nature and analyzing the sensitivity of these models to environmental parameters are of great importance for fire study and management activities. A comprehensive sensitivity analysis of a general and modified quasi-physical model is provided in the current study to predict parameters that affect grassland fire propagation patterns. The model considers radiative heat transfer from the flame and fuel body and convective heat transfer to predict the fire's rate of spread and the grassland fire patterns. The model's sensitivity to ten main parameters that affect fire propagation, including temperature, humidity, wind speed, specifications of vegetable fuel, etc., is studied, and the results are discussed and analyzed. The model's capability is validated with experimental studies and a comprehensive physical model WFDS. The model's capability, as quasi-physical, faster than the real-time model, shows high consistency in fire propagation parameters compared with experimental real data from the Australian grassland fire Cases C064 and F19. The comprehensive sensitivity analysis provided in this study resulted in a modified equation for the corrected rate of fire spread which shows quite an improvement in ROS prediction from 5% to 65% compared with the experimental results. The study could be a base model for future studies, especially for those researchers who aim to design experiments and numerical studies for grassland fire spread behavior. [ABSTRACT FROM AUTHOR]

Using meteorological and grassland fire data for Hulun Buir, China, from 1990 to 2019, we explored variation in meteorological factors, assessed the frequencies and areas of grassland fires, and used an autoregressive distributed lag (ARDL) model to investigate correlations between burned areas and meteorological factors. Fires in Hulun Buir grassland mainly occurred between 1990 and 1999; from 1990 to 2009, most fires occurred in Prairie Chenbarhu Banner, Xin Barag Right Banner and Xin Barag Left Banner. Grassland fires in Hulun Buir decreased significantly from 2010 to 2019. From 1990 to 2019, grassland fires mostly occurred in spring and autumn. Among the seven meteorological factors, wind speed, relative humidity and sunshine hours were most strongly correlated with burned areas. Regarding long-term and short-term effects, relative humidity had the biggest influence on burned area. The results demonstrated that ARDL models can reveal the long-term and short-term sensitivity of meteorological factors related to fire, and the ARDL econometrics method can be used effectively to study trends in grassland fire burning area. [ABSTRACT FROM AUTHOR]

Background: Directly after snowmelt, northern grasslands typically have highly flammable fuel-beds consisting of 100% grass litter. With green-up, the addition of high-moisture foliage leads to progressively decreasing fire hazard. Aims: Our aim was to create a fire-danger index for northern grasslands that incorporated grass phenology. Methods: We made use of 25 years of Swedish wildfire data and 56 experimental fires conducted during one full fire-season, merged with established models for moisture content and flame spread rates. Refined data on equilibrium moisture content of grass litter were obtained through laboratory tests. Key results: The RING (Rate of spread In Northern Grasslands) model uses cumulative air temperature as a proxy for growing season progression. Three independent functions account for impact of wind, moisture content and the damping effect of live grass, respectively. The latter results in exponentially decaying rate of spread (ROS) with the progressing season. Following the field experiments, green grass proportion as low as 10–20% (live/dead dry-mass) resulted in model-ROS so reduced that the grassland fire season could effectively be considered over. Conclusions: The model, calculated from standard meteorological data only, matches the experimental results and separately performed validation tests, as well as wildfire dispatch data. Implications: RING has been used in Sweden since 2021 and is likely applicable to other northern regions as well. After snowmelt, northern grasslands typically consist of highly flammable grass litter. We analysed a series of experimental grassland fires, as well as Swedish wildfire dispatch data, to isolate the impeding effect of grass phenology on fire propagation. A complete grassfire danger index is presented, likely applicable to most regions with cold (snow-covered) winters. [ABSTRACT FROM AUTHOR]

Silver sagebrush (Artemisia cana) is a low shrub species that is common in northern mixed grass prairies and that provides important wildlife habitat. Silver sagebrush habitat has historically experienced frequent wildfires, but postsettlement fire control efforts have reduced fire frequencies. The effects of fire on silver sagebrush growth and regenera¬tion are not clearly understood; this study examined the effects of fire on silver sagebrush regeneration by evaluating post- fire plant size and distribution data from one season. Sites were located in the northern mixed prairie in Saskatchewan, Canada, and included pastures where the plant community was recovering from both prescribed fires and an intense wildfire. Silver sagebrush responded to fire by producing new shoots via rhizomes, with some plants also regenerating from the crown. No seedlings were observed. Larger plants and dense stands of silver sagebrush appeared to regenerate more successfully than did thin stands. These results demonstrated that silver sagebrush recovery is primarily vegetative, with clone mortality rare. [ABSTRACT FROM AUTHOR]

Background. Increasing extreme weather events due to climate change require updated environmental monitoring and prediction systems in Germany. Aim. The Grassland Fire Index (GLFI), developed by the German Meteorological Service ~15 years ago for temperate climates, was revised to improve fire-danger predictions during the fire season. Our paper gives insight into the new model version. Methods. The former fire-behaviour core, i.e. Fosberg's Fire Weather Index (FWI), is replaced by the standardised fire-reaction intensity, a different fuelmoisture of extinction term, and a replica of the fire-spread rate of the Canadian FFBP-System. A standardised ease-of-ignition index is added as a measure of ignition success. The fire module is supplied with diurnal dead-grass fuel-moisture calculations based on the water-budget and energy-balance concept. Key results. The GLFI output is compared with diurnal fuelmoisture measurements and results of Wotton's Grass-Fuel-Moisture model, Fosberg's FWI, and Cheney's rate of spread equation. The GLFI computes periods with a high fuel moisture more realistically, whereas it exceeds Cheney's rate-of-fire spread systematically at lower wind speeds, which leads to higher danger ratings during calm-air conditions (as requested by users). Conclusions and Implications. The GLFI estimates dead-fuel moisture and fire danger on open, horizontal topography according to the current scientific level. Model extensions are necessary to run the model on complex topography under varying greenness and occasional frost conditions. [ABSTRACT FROM AUTHOR]

With the Outline of the Action Plan for the Scientific Quality of the Whole People (2021–2035) and the “double reduction” policy, the popular science education of primary and middle school students has gradually received attention of the public. At the same time, the Party and the State also have new requirements for the ideological and political training of young people. In this case, the combination of popular science work and curriculum ideological and political work is a good way of education. In the exploration and practice of the integration of chemical science popularization and curriculum ideology and politics, we try to summarize the “three-stage style” in the ideological and political construction of science popularization. This article will take the popular science exhibition course “a spark starts a prairie fire” as an example, and use the popular science “three-stage style” from the simple to the deep. This paper analyzes and discusses the process of integrating ideological and political education into popular science curriculum for teenagers. [ABSTRACT FROM AUTHOR]

Fires greatly threaten the grassland ecosystem, human life, and economic development. However, since limited research focuses on grassland fire prediction, it is necessary to find a better method to predict the probability of grassland-fire occurrence. Multiple environmental variables impact fire occurrence. After selecting natural variables based on remote sensing data and anthropogenic variables, we built regression models of grassland fire probability, taking into account historical fire points and variables in Inner Mongolia. We arrived at three methods to identify grassland fire drivers and predict fire probability: global logistic regression, geographically weighted logistic regression, and random forest. According to the results, the random forest model had the best predictive effect. Nine variables selected by a geographically weighted logistic regression model exercised a spatially unbalanced influence on grassland fires. The three models all showed that meteorological factors and a normalized difference vegetation index (NDVI) were of great importance to grassland fire occurrence. In Inner Mongolia, grassland fires occurring in different areas indicated varying responses to the influencing drivers, and areas that differed in their natural and geographical conditions had different fire-prevention periods. Thus, a grassland fire management strategy based on local conditions should be advocated, and existing fire-monitoring systems based on original meteorological factors should be improved by adding remote sensing data of grassland fuels to increase accuracy. [ABSTRACT FROM AUTHOR]

Summary: One of the multiple threats to protected areas worldwide, invasive plant species have the potential to decrease biodiversity and ecosystem function. We studied changes in infestation by two widespread invasive plant species – Chromolaena odorata and Mikania micrantha – in India's Manas National Park, a critical conservation site for threatened flora and fauna. Based on field surveys in 2011 and 2019, we found that C. odorata and M. micrantha were present in most of the sampled plots and had newly invaded over 20% of the plots. However, the abundance of M. micrantha decreased in 45% of the plots while C. odorata increased in >50% of the plots. We used a decision tree-based regression with environmental variables as predictors to generate the distribution, abundance and invasion risk maps of the two species. Among environmental variables, road proximity and fire frequency had the strongest influences, respectively, on C. odorata and M. micrantha. Invaded quadrats exhibited lower native-plant diversity than non-invaded quadrats, and C. odorata specifically had a strong negative association with native-plant community structure. These invasive species have increased their range and abundance, and our predicted invasion risk maps indicate the areas where management intervention is urgently needed. [ABSTRACT FROM AUTHOR]

This article aims at analysing the factors and forces that affect the Amhara and Oromo elites' political discourses and their relations in the post-2018 period. The study employs a qualitative research approach, with data drawn from articles, books, online video records, reports, and interviews. During the Amhara and Oromo popular protests, politicians allied to ensure solidarity between the two groups and unleash a new political setup. However, the study reveals that the Amhara and Oromo elites have failed to heal the historical contradictions and narrow the divergent interests lingering between them for several decades using the opportunities created in the post-2018 era. In the new political setup, the Amhara and Oromo elites engage in competition for discourse, territory, and power afresh, contrary to the demand to create solidarity using the 'Segegna Teff metaphor as a leading discourse. After the inception of the reform in 2018 in Ethiopia, they relapsed into a 'fire and grass' metaphor that sustains fault lines between the two largest groups. To get out of this problem, discussions and elite bargaining are essential. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)