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Context: Vegetation remnants enveloped by built up areas tend to drift away in their character from vegetation on similar sites in more extensive patches of native vegetation, but may stabilise in synthetic (novel) form with time in harmony with disturbance regimes and environmental change. Managers may be able to induce a synthetic state that maintains the nature conservation values of such remnants. Aims: We examine the degree to which the nature conservation values of the the vegetation of a 19th century urban reserve in nipaluna (Hobart), lutruwita (Tasmania) changed between 1974 and 2022/23 in a period of climate change and changes in vegetation management, with the aim of discerning appropriate conservation management regimes. Methods: Sixty-nine 1 × 15 m quadrats were randomly located in the non-cultivated part of the Domain in 1974 and roughly relocated for sampling in 1984, 1994, 2001 and 2022. Tree diameters were recorded using the point-centred quarter method in 1974, 1984, 1994, 2001 and 2023. The responses of native and exotic species richness, and the frequency of the more common species, to time and other predictor variables related to time since last fire, evidence of mowing at the time of the survey, and topography were determined using linear modelling, correlation, analysis of variance and chi-squared. Key results: The native tree Allocasuarina verticillata was the only significantly varying consistent increaser of 67 taxa. The native perennial herbs Acaena echinata and Leptorhynchos squamatus and the non-native shrubby weed Chrysanthemoides monilifera were the only significantly varying consistent decreasers. However, several rare and threatened species too infrequent for statistical analysis also declined between 2022/23 and 2000. Twenty-four of the 67 taxa with sufficient data for analysis did not significantly vary among years. The percentage of native species in quadrats did not change through time. It was negatively related to mowing and the time since fire. Native tree stems 10–30 cm in diameter and those over 30 cm increased through time, whereas those less than 10 cm in diameter increased dramatically until 2000, then strongly decreased by 2023. Total stem density increased through time. Conclusions: Mowing and fire regimes strongly influenced the distributions of a large proportion of native taxa independent of time and underlying environment, largely by controlling the density of the small tree layer, which can potentially form closed-forest without eucalypts. Implications: It is possible to use fire, mowing and slashing to maintain nature conservation values in synthetic urban grassy woodland, although the maintenance of the rarest native species requires more specific and varied interventions. Does native vegetation in urban parks change over time? Yes and no is the answer we found after analysing data collected over a 50-year period. Whereas some sites are stable, management interventions such as weeding, burning, mowing and mechanical removal are useful tools to maintain healthy patches of native vegetation in urban areas. Map created by Ian Jenkinson. [ABSTRACT FROM AUTHOR]

Abstract: Background: Contemporary and projected shifts in global fire regimes highlight the importance of understanding how fire affects ecosystem function and biodiversity across taxa and geographies. Pyrodiversity, or heterogeneity in fire history, is often an important driver of biodiversity, though it has been largely overlooked until relatively recently. In this paper, we synthesise previous research to develop a theoretical framework on pyrodiversity–biodiversity relationships and propose future research and conservation management directions. Theoretical Framework: Pyrodiversity may affect biodiversity by diversifying available ecological niches, stabilising community networks and/or supporting diverse species pools available for post‐fire colonisation. Further, pyrodiversity's effects on biodiversity vary across different spatial, temporal and organismal scales depending on the mobility and other life history traits of the organisms in question and may be mediated by regional eco‐evolutionary factors such as historical fire regimes. Developing a generalisable understanding of pyrodiversity effects on biodiversity has been challenging, in part because pyrodiversity can be quantified in various ways. Applying the Pyrodiversity Concept: Exclusion of Indigenous fire stewardship, fire suppression, increased unplanned ignitions and climate change have led to dramatic shifts in fire regimes globally. Such shifts include departures from historic levels of pyrodiversity and add to existing challenges to biodiversity conservation in fire‐prone landscapes. Managers navigating these challenges can be aided by targeted research into observed contemporary pyrodiversity–biodiversity relationships as well as knowledge of historical reference conditions informed by both Indigenous and local ecological knowledge and western science. Future Research Directions: Several promising avenues exist for the advancement of pyrodiversity science to further both theoretical and practical goals. These lines of investigation include but are not limited to (1) testing the increasing variety of pyrodiversity metrics and analytical approaches; (2) assessing the spatial and temporal scale‐dependence of pyrodiversity's influence; (3) reconstructing historical pyrodiversity patterns and developing methods for predicting and/or promoting future pyrodiversity; and (4) expanding the focus of pyrodiversity science beyond biodiversity to better understand its influence on ecosystem function and processes more broadly.

Individual and interactive effects of changing climate and shifting fire regimes are influencing many plant species across the globe. Climate change will likely have significant impacts on plant population viability over time by altering environmental conditions and wildfire regimes as well as influencing species demographic traits. However, the outcomes of these complex interactions for different plant functional types under future climate conditions have been rarely examined. We used a proof‐of‐concept case‐study approach to model multiple plant species across two functional plant types, obligate seeder and facultative resprouter, to examine the interactive effects of demographic shifts and fire regime change on population persistence across two landscapes of over 7000 km2 in temperate southeastern Australia. Our approach involves a novel combination of a fire regime simulation tool with a spatially explicit population viability analysis model. We simulated fire regimes under six different future climates representing different temperature and precipitation shifts and combined them with 16 hypothetical plant demographic change scenarios, characterised by changes to individual or multiple plant demographic processes. Plant populations were more likely to decline or become extinct due to changes in demographic processes than in the fire regime alone. Although both functional types were vulnerable to climate‐induced changes in demography, obligate seeder persistence was also negatively influenced by future fire regimes characterised by shorter fire intervals. Integrating fire regime simulations with spatially explicit population viability analyses increased our capacity to identify those plant functional types most at risk of extinction, and why, as fire regimes change with climate change. This flexible framework is a first step in exploring the complex interactions that will determine plant viability under changing climates and will improve research and fire management prioritisation for species into the future. [ABSTRACT FROM AUTHOR]

Background: Wildfire frequency, magnitude and impacts in wildland–urban interface (WUI) areas are increasing in the Mediterranean Basin. Aims: We investigated the role played by socio-economic, vegetation, climatic, and zootechnical drivers on WUI wildfire patterns (area burned and wildfire ignitions) in Sardinia, Italy. Methods: We defined WUI as the 100-m buffer area of the anthropic layers. We created a comprehensive and multi-year dataset of explanatory variables and wildfires, and then trained a set of models and evaluated their performances in predicting WUI fires. We used the best models to assess the single variable's importance and map wildfire patterns. Key results: Random Forest and Support Vector Machine were the best performing models. In broad terms, wildfire patterns at WUI were influenced by socio-economic factors and herbaceous vegetation types. Conclusions: Machine learning models can be useful tools to predict wildfire ignitions and area burned at WUI in Mediterranean areas. Implications: Improved knowledge of the main drivers of wildfires at WUI in fire-prone Mediterranean areas can foster the development or optimisation of wildfire risk reduction and prevention strategies. We modelled wildfire activity in wildland–urban interface areas of Sardinia, Italy by applying a set of predictive models to investigate how climatic, vegetation, zootechnical, and socio-economic drivers influence wildfire ignitions and area burned. Wildfire patterns at WUI were strongly affected by socio-economic factors and by herbaceous vegetation. [ABSTRACT FROM AUTHOR]

Marginal populations of temperate species at the leading edge of their range will likely play a key role at the boreal‐temperate ecotone (BTE) in the face of climate changes. In eastern North America, red maple (Acer rubrum L.) is the most abundant temperate tree species encroaching into the boreal forest. In order to provide useful insights about possible responses to climate change and anticipate the formation of new assemblages, this study relies on long‐term Holocene data from forest soil wood macrofossils (charcoal and ligneous remains) and contemporary stand analyses to assess the postglacial origin and modern‐day dynamics of red maple at its leading edge within the BTE. We sampled the soils of eight marginal red maple stands. Macroscopic charcoal particles and ligneous remains were identified using microanatomical characteristics. Macrofossils of temperate tree species were radiocarbon dated to reconstruct their long‐term stand‐scale history. Contemporary dynamics (<200 years) were assessed by analyzing tree size structure of all stems within 400 m2 plots, minimal stand age from tree‐ring dating, as well as the recent occurrence of fire and logging from published ecoforest data. White pine (Pinus strobus L.), the only other temperate tree species that was identified, was present 6500–4000 years ago, during the mid‐Holocene thermal maximum but decreased during the cooler and fire‐prone late‐Holocene Neoglacial (4000 years ago to present). By contrast, red maple was found at its current northern limit since the last 4000 years. Modern‐day marginal red maple stands are self‐regenerating populations that established following a recent stand‐replacing disturbance (wildfire or clearcut). The present‐day increase of anthropogenic disturbances within the BTE could mirror the Neoglacial increase in fire activity that fostered red maple during the Holocene. We thus predict that red maple is poised to increase in abundance within the BTE, which should facilitate the northward establishment of other temperate deciduous species into the boreal forest prompted by the new conditions brought about by anthropogenic or climate change‐induced disturbances. [ABSTRACT FROM AUTHOR]

Many plants rely on soil seedbanks to persist in fire‐prone ecosystems. However, knowledge of plant responses to fire is largely based on above‐ground dynamics. Quantifying how fire influences the seedbank of a diverse range of species will improve fire management.Here, we aim to understand how the timing of fires influences species occurrence in the soil seedbank, and how this relates to species traits, in a Mediterranean‐type ecosystem. We sampled the soil seedbank across 57 sites that represent a range of fire frequencies (1–9 fires in 81 years) and time since fire (1–81 years). Through a 15‐month germination experiment, we identified 39,701 germinates from 245 plant species. Using nonlinear models, we quantified the responses of 75 species' soil seedbanks to fire history and compared these to above‐ground responses.Fire influenced species' soil seedbanks according to seed longevity and species' life‐history traits. We observed a response of 15 species' seedbanks to time since fire: All were species with long‐lived seed, including eight annuals, five resprouters and an obligate seeder. Similarly, we observed a response of 17 species' seedbanks to fire frequency, 16 of which had long‐lived seed. Extensive periods without fire (>40 years) increase seedbank availability for annuals that form a long‐lived seedbank, and frequent fire (every ≤15 years) depletes it. We did not detect a consistent influence of fire on species from several other functional types. Many (53%) species found in the soil seedbank were not found in the above‐ground vegetation, and seven of the 22 modelled displayed an above‐ground influence of fire.Synthesis and applications: Fire frequency influences the probability of species occurrence in the soil seedbank. Frequent fire depletes seed availability of species that depend on long‐lived soil seedbanks for persistence. Yet, other species, including perennials with short‐lived seed storage, appear to be resilient to the frequency of fires experienced to date. We suggest fire management should aim to generate variation in fire frequencies within the landscape, including areas of low fire frequency, tailored to maintain rich plant diversity within the soil seedbank. [ABSTRACT FROM AUTHOR]

We use case studies to explore the impact of changed fire regimes on vegetation structure and fuel risk in Southeast Queensland, Australia. Multiple studies report high intensity wildfires promote excessive shrub and sapling densities, which increase elevated fuel hazard. We argue asset protection burns in dry conditions can cause similar vegetation thickening to an intense wildfire, which increases fire severity risk due to increased elevated fuel loads. We demonstrate regular low intensity burning with adequate soil moisture can achieve fuel reduction objectives. This provides a longer-term solution that promotes risk reduction to communities, whilst leading to better ecological outcomes and reduced cost of implementation over the long-term. Case studies explore the impact of fire regimes on vegetation structure and fuel risk in Southeast Queensland, Australia. High intensity wildfires and asset protection burns can promote excessive shrub and sapling densities, increasing elevated fuel loads. We recommend burns are done under moist, mild conditions to maintain an open forest structure and minimise fire hazard. This article belongs to the Collection Fire and Climate. [ABSTRACT FROM AUTHOR]

Background: Knowledge of how fire regimes influence flammability, and its role in shaping future fire regimes, exists mostly at species composition and ecosystem levels. The effect of fire regimes on fuel at the chemical level is poorly known. Aim: We aimed to empirically investigate the association between recent fire history and forest foliage chemistry; and to explore potential implications for forest fuel flammability. Methods: Using an orthogonal study design, we investigated the effects of fire frequency and time since fire on the chemical composition of Eucalyptus pilularis leaves from forest canopies and surface litter in south-eastern Australia. Key results: We found high fire frequency (fire-return interval 10–13 years) was associated with higher C:N, C:P, and C:K ratios in E. pilularis surface litter, and higher C:P in canopy leaves. Conclusions: Nutrients including nitrogen and phosphorous reduce flammability of plant tissues, and hence, the observed differences in leaf nutrients between high and low fire frequency sites could have important implications for future flammability of these forests. Implications: Our study has demonstrated a relationship between fire frequency and leaf nutrient stoichiometry, which may act as a mechanism through which repeated fires could increase fuel flammability. This warrants further investigation in other environments. Knowledge of how past fires may influence the future flammability of ecosystems remains poorly resolved. Here, we report significant effects of past fire frequency on the chemical properties of canopy leaves and leaf litter in a coastal Eucalyptus forest, which may have important implications for future forest flammability. [ABSTRACT FROM AUTHOR]

There is a consensus that fire should be actively managed in tropical savannas to decrease wildfire risks, firefighting costs, and social conflicts as well as to promote ecosystem conservation. Selection and participatory monitoring of the effects of fire on cultural keystone species may be an efficient way to involve local stakeholders and inform management decisions. In this study, we investigated the effects of different fire regimes on a cultural keystone species in Central Brazil. With the support of diverse multiethnic groups of local fire brigades, we sampled Hancornia speciosa (Apocynaceae) populations across a vast regional range of 18 traditional territories (Indigenous Lands and Quilombola Territories) as well as four restricted Protected Areas. We considered areas under wildfires (WF), prescribed burns (PB) and fire exclusion (FE) and quantified tree mortality, canopy damage, loss of reproductive structures and fruit production following a simplified field protocol. Areas with H. speciosa populations were identified and classified according to their fire history, and in each sampled area, adult plants were evaluated. We hypothesized that WF would have larger negative impact on the population parameters measured, while FE would increase plant survival and fruit production. We found that tree mortality, canopy damage, and loss of reproductive structures were higher in areas affected by wildfires, which also had the lowest fruit production per plant compared to PB and FE areas, corroborating our hypotheses. However, we also found higher mortality in FE areas compared to PB ones, probably due to plant diseases in areas with longer FE. Considering these results and that the attempts to exclude fire from fire-prone ecosystems commonly lead to periodic wildfires, we argue that the Integrated Fire Management program in course in federal Protected Areas in Brazil—based on early dry season prescribed fires—is a good management option for this, and likely other, cultural keystone species in the Brazilian savanna. [ABSTRACT FROM AUTHOR]

Abstract Marginal populations of temperate species at the leading edge of their range will likely play a key role at the boreal‐temperate ecotone (BTE) in the face of climate changes. In eastern North America, red maple (Acer rubrum L.) is the most abundant temperate tree species encroaching into the boreal forest. In order to provide useful insights about possible responses to climate change and anticipate the formation of new assemblages, this study relies on long‐term Holocene data from forest soil wood macrofossils (charcoal and ligneous remains) and contemporary stand analyses to assess the postglacial origin and modern‐day dynamics of red maple at its leading edge within the BTE. We sampled the soils of eight marginal red maple stands. Macroscopic charcoal particles and ligneous remains were identified using microanatomical characteristics. Macrofossils of temperate tree species were radiocarbon dated to reconstruct their long‐term stand‐scale history. Contemporary dynamics (

Societal Impact Statement The relationship between rainfall, fire and habitat can display incongruencies. The 2021 Malagasy Grassy Biomes Workshop identified understanding fire regimes as a knowledge gap. This study pinpoints regions where anthropogenic fire has the potential to transform or has transformed habitat to treeless‐grassland, by identifying landscape‐scale, island‐wide fire anomalies across half of Madagascar. Its eastern forests burn like savannas, and central‐western grasslands burn frequently and intensely despite receiving rainfall usually associated with forest and fire‐absence. Recognising the incongruity and better understanding its drivers can mitigate against landscape‐scale degradation, improving ecological function, and human well‐being. Summary Data show that since 1953, human‐lit fires on Madagascar have transformed clear‐cut forest to treeless‐grasslands. To address the extent of Malagasy treeless‐grasslands at human settlement, the 2021 Malagasy Grassy Biomes Workshop identified the role of fire as a critical knowledge‐gap for understanding ecological function. The relationship between mean annual precipitation (MAP), fire and habitat is well established across mesic systems. Anthropogenically transformed habitats often deviate from expected ecological patterns, so we tested for landscape‐scale, island‐wide MAP‐related fire and habitat anomalies. We collated Malagasy fire, habitat and MAP datasets, identifying location and scale of incongruities relative to global fire‐habitat‐MAP expectations. Next, we tested for mismatches in fire regimes (frequency, timing, extent and intensity of fires) between Malagasy and equivalent global biomes, using global, comprehensive landscape‐scale fire regime data. Across half of Madagascar, fire frequency and habitat are decoupled from MAP, and fire regimes across Malagasy ecoregions differ significantly from those in shared biomes elsewhere in the world. Landscape‐scale incongruities span Malagasy eastern forests (which burn like savanna systems) and central‐western treeless‐grasslands, which burn frequently and intensely despite receiving MAP typical of forest presence and fire‐absence, globally. Fire‐MAP incongruities identify potentially transformed areas, or those undergoing transformation by fire, and establish a platform for investigating the nuanced social, political and ecological dynamics that may contribute to and perpetuate these anomalies. Incongruities also highlight the anthropogenic landscape degradation associated with fire anomalies. Addressing these impacts can facilitate restoration of ecological function, productivity and food security, benefiting biodiversity and humans at multiple scales.

Societal Impact Statement: The relationship between rainfall, fire and habitat can display incongruencies. The 2021 Malagasy Grassy Biomes Workshop identified understanding fire regimes as a knowledge gap. This study pinpoints regions where anthropogenic fire has the potential to transform or has transformed habitat to treeless‐grassland, by identifying landscape‐scale, island‐wide fire anomalies across half of Madagascar. Its eastern forests burn like savannas, and central‐western grasslands burn frequently and intensely despite receiving rainfall usually associated with forest and fire‐absence. Recognising the incongruity and better understanding its drivers can mitigate against landscape‐scale degradation, improving ecological function, and human well‐being. Summary: Data show that since 1953, human‐lit fires on Madagascar have transformed clear‐cut forest to treeless‐grasslands. To address the extent of Malagasy treeless‐grasslands at human settlement, the 2021 Malagasy Grassy Biomes Workshop identified the role of fire as a critical knowledge‐gap for understanding ecological function. The relationship between mean annual precipitation (MAP), fire and habitat is well established across mesic systems. Anthropogenically transformed habitats often deviate from expected ecological patterns, so we tested for landscape‐scale, island‐wide MAP‐related fire and habitat anomalies.We collated Malagasy fire, habitat and MAP datasets, identifying location and scale of incongruities relative to global fire‐habitat‐MAP expectations. Next, we tested for mismatches in fire regimes (frequency, timing, extent and intensity of fires) between Malagasy and equivalent global biomes, using global, comprehensive landscape‐scale fire regime data.Across half of Madagascar, fire frequency and habitat are decoupled from MAP, and fire regimes across Malagasy ecoregions differ significantly from those in shared biomes elsewhere in the world. Landscape‐scale incongruities span Malagasy eastern forests (which burn like savanna systems) and central‐western treeless‐grasslands, which burn frequently and intensely despite receiving MAP typical of forest presence and fire‐absence, globally.Fire‐MAP incongruities identify potentially transformed areas, or those undergoing transformation by fire, and establish a platform for investigating the nuanced social, political and ecological dynamics that may contribute to and perpetuate these anomalies. Incongruities also highlight the anthropogenic landscape degradation associated with fire anomalies. Addressing these impacts can facilitate restoration of ecological function, productivity and food security, benefiting biodiversity and humans at multiple scales. [ABSTRACT FROM AUTHOR]

Urbanization and climate change have led to an increasing number of wildfires in China in recent years, posing a direct threat to life, property, and social development. These areas facing severe wildfire risk are mainly concentrated in the Wildland-Urban Interface (WUI). Although much research has been conducted on wildfire management in China, one of the critical constraints is that there is not yet a WUI distribution map that can meet the needs of forest fire management in China. The present study proposes an approach to identify WUI areas in mainland China between 2008 and 2020 by analyzing the impact of wildfire events on communities. Using historical fire occurrence data, we explored the spatial and temporal distribution patterns of WUI fires in various geographic regions. Using the random forest model, we predicted the spatial distribution of WUI fires and identified the key factors affecting their occurrence. The results show that the WUI area in China has been rapidly expanding since 2008, with a growth rate of 15.2 × 103 km2/a, especially in the densely populated and economically developed eastern regions. The seasons of WUI fires varied across regions. Both spring and autumn are major seasons for WUI fire occurrence in northern China. In contrast, more than 80 % of WUI fires in southern China occurred in winter and spring. According to the findings generated by the random forest analysis, weather patterns marked by low levels of rainfall and elevated temperatures during both spring and fall seasons are the primary atmospheric contributors to the incidence of WUI fires. Our study indicated that repeated human activities within southern China also increased the probability of fire occurrence. We suggest that better prediction of fire-prone weather and improved regional forest fire management can help decrease the incidence of WUI fires. In addition, future efforts should focus on enhancing the long-term monitoring and predictive capabilities of fuel moisture content.

Fire regimes are often considered to be either driven by climate, fuel load or human activities. A significant proportion of fires across various ecosystems occur via large fire events. Recently, suggestions have been made that fires are becoming more severe and frequent as a consequence of current climate change. Although there are many factors influencing fire events, scientists have not found a suitable framework that can provide for understanding fires at the macroscale level. This review article proposes a new conceptual framework to better understand fire regimes. The proposed framework relies on a biogeographical perspective of fire regimes that include characteristics that have been underestimated in previous frameworks and to mitigate time as well as spatial scale issues at the macrolevel.

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Aim: To provide the first regional analysis of contemporary drivers of Pacific Island fire regimes. Location: Islands of Palau, Yap, Guam, Rota, Tinian, Saipan, Chuuk, Pohnpei, Kosrae. Time Period: 1950‐present. Methods: We used land cover, soil maps and contemporary fire histories to (1) describe the relationships among fire activity, vegetation, rainfall and island geography and population; (2) examine the spatial associations of forest and savanna vegetation with respect to fire and soil types; and (3) link fire and savanna distribution to intra‐annual and inter‐annual rainfall variability. Results: Savanna extent was positively correlated with island age and the range of mean monthly rainfall. The percent of area burned annually reached upwards of 2%–10% of island land areas, correlated positively with rainfall seasonality, and occurred largely within savannas. Savannas were more frequent on acidic soils with higher aluminium than forests but distributed across all soil types. El Niño intensity correlated negatively with dry season rainfall over the entire study region and positively with annual area burned on Guam. Main Conclusions: The contemporary extents of savannas in Micronesia reflect Pacific Islanders' long‐term use of fire to shape vegetation and are modulated by inter‐ and intra‐annual rainfall variability. These relationships provide baseline information for ongoing fire management and mitigation projects throughout Micronesia and critical insight for assessing and anticipating fire risk in other insular areas where fire data are limited. [ABSTRACT FROM AUTHOR]

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This study describes spatial and temporal patterns in fire across the US Western Great Plains over the last 40 years. Although pyrogeographic studies have explored the nexus of fire patterns in relation to the bio-physical environment and socio-ecological trends, most of this research has focused on forested ecosystems and regions long known for conflict between wildfires and human development, especially at the wildland–urban interface. But evidence suggests large wildfire activity is increasing in the US Great Plains, and the Western Great Plains—a Land Resource Region comprised of four ecoregions, Northwestern Plains, High Plains, Nebraska Sandhills, and Southwestern Tablelands—not only contains some of the largest areas of rangeland in the US but also the highest concentration of public land in the Great Plains. As such, the Western Great Plains provides an opportunity to explore fire activity in primarily rural landscapes with a combination of public and private ownership, all dominated by rangeland vegetation. We combined several publicly-available datasets containing fire records between 1992 and 2020 to create two databases, one with georeferenced point data on 60,575 wildfire events in the region, and another with georeferenced perimeter data for 2665 fires. Ignition by humans was the dominant cause of fires. No ecoregion showed a statistically significant trend towards either increasing or decreasing the annual burned area. The Northwestern Plains had the most burned area and the greatest number of incidents—consistently around or above 1000 incidents per year since 1992—with the majority in July. The High Plains showed the greatest increase in annual fire incidence, never reaching more than 200–300 per year 1992–2009, and averaging above 1000 incidents per year since 2010. Few long-term trends in human population, weather, or fuel metrics appear strongly associated with fire patterns in any ecoregion, although the years 2006, 2012, and 2017 stood out for their levels of fire activity, and these years often frequently logged extreme values in wildland fuel metrics. These relationships merit much closer examination in the Western Great Plains, because like other rangeland-dominated landscapes, the fine fuels that comprise these wildland fuelbeds are much more responsive to fine-scale changes in moisture conditions. Rural Western Great Plains landscapes are a mosaic of public and private land ownership, and an increasing impact of wildfires on public grazing lands—which are often situated within other jurisdictions or ownership—will likely have an impact on rural livelihoods. [ABSTRACT FROM AUTHOR]

Fire regimes are often considered to be either driven by climate, fuel load or human activities. A significant proportion of fires across various ecosystems occur via large fire events. Recently, suggestions have been made that fires are becoming more severe and frequent as a consequence of current climate change. Although there are many factors influencing fire events, scientists have not found a suitable framework that can provide for understanding fires at the macroscale level. This review article proposes a new conceptual framework to better understand fire regimes. The proposed framework relies on a biogeographical perspective of fire regimes that include characteristics that have been underestimated in previous frameworks and to mitigate time as well as spatial scale issues at the macrolevel. [ABSTRACT FROM AUTHOR]

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Detailed information about the historical range of variability in wildfire activity informs adaptation to future climate and disturbance regimes. Here, we describe one of the first annually resolved reconstructions of historical (1500–1900 ce) fire occurrence in coast Douglas‐fir dominated forests of the west slope of the Cascade Range in western Oregon. Mean fire return intervals (MFRIs) across 16 sites within our study area ranged from 6 to 165 years. Variability in MFRIs was strongly associated with average maximum summer vapor pressure deficit. Fire occurred infrequently in Douglas‐fir forest stands seral to mountain hemlock or silver fir, but fire frequency was much shorter than predicted by theory in other forest types. MFRIs within Douglas‐fir stands seral to western hemlock or grand fir ranged from 19 to 45 years, and MFRIs in stands seral to Douglas‐fir ranged from 6 to 11 years. There was little synchrony in fire occurrence or tree establishment across 16 sites separated by 4 km. The lack of synchrony in fire suggests that large, wind‐driven fire events that are often considered to be characteristic of coast Douglas‐fir forests were not an important driver of succession in our study area during the last ~400–500 years. Climate was more arid than normal during fire years in most forest types, but historical fire in stands seral to Douglas‐fir was strongly associated with antecedent moisture and less strongly associated with drought. We interpret the extraordinary tempo of fire we observed in stands seral to Douglas‐fir and the unique climate pattern associated with fire in these stands to be indicative of Indigenous fire stewardship. This study provides evidence of far more frequent historical fire in coast Douglas‐fir forests than assumed by managers or scientists—including some of the most frequent fire return intervals documented in the Pacific Northwest. We recommend additional research across the western Cascades to create a comprehensive account of historical fire in highly productive forests with significant cultural, economic, and ecological importance. [ABSTRACT FROM AUTHOR]

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Question: Soil properties can play a crucial role in influencing the abundance and distribution of plant species. Fire regimes can also have substantial impacts on plant community composition. However, few studies have examined the effects of both fire regimes and soil properties on the occurrence of rare plant species. Here, we asked if rare species have specific soil and fire regime associations relative to common species, and if soil properties may explain potential fire effects. Location: Booderee National Park, southeastern Australia. Methods: We collected soil cores and completed vegetation surveys on 42 sites in Sydney Coastal Dry Sclerophyll Forest vegetation. We tested for associations between the number of rare species and common species present in relation to three soil chemical properties (available phosphorus, ammonium and organic carbon), fire frequency, and time since fire. Results: We found that rare and common species were not associated with any of the examined soil properties. However, rare species were associated with sites with a high fire frequency, while common species were negatively associated with time since fire. Conclusions: Our results indicate that rare species' occurrence patterns may be influenced by the direct effects of fire or mediated by multiple factors, rather than shaped solely by soil properties in our study area. Future work to understand the factors that underpin rare species' occurrence patterns in response to fire is critical to develop fire management protocols that effectively conserve rare species in dry sclerophyll forests. [ABSTRACT FROM AUTHOR]

Fire-driven animal evolution may occur rapidly in the Pyrocene, with potentially significant implications for biodiversity conservation. Fire is an important evolutionary force that exerts strong selective pressure on many domains of life on Earth, including animals. Innovative research has demonstrated genetic evolution by animals in response to fire and fire regimes, and suggests that evolution in wild populations can occur more quickly than was previously thought. Fire regimes are a major agent of evolution in terrestrial animals. Changing fire regimes and the capacity for rapid evolution in wild animal populations suggests the potential for rapid, fire-driven adaptive animal evolution in the Pyrocene. Fire drives multiple modes of evolutionary change, including stabilizing, directional, disruptive, and fluctuating selection, and can strongly influence gene flow and genetic drift. Ongoing and future research in fire-driven animal evolution will benefit from further development of generalizable hypotheses, studies conducted in highly responsive taxa, and linking fire-adapted phenotypes to their underlying genetic basis. A better understanding of evolutionary responses to fire has the potential to positively influence conservation strategies that embrace evolutionary resilience to fire in the Pyrocene. [ABSTRACT FROM AUTHOR]

Abstract Detailed information about the historical range of variability in wildfire activity informs adaptation to future climate and disturbance regimes. Here, we describe one of the first annually resolved reconstructions of historical (1500–1900 ce) fire occurrence in coast Douglas‐fir dominated forests of the west slope of the Cascade Range in western Oregon. Mean fire return intervals (MFRIs) across 16 sites within our study area ranged from 6 to 165 years. Variability in MFRIs was strongly associated with average maximum summer vapor pressure deficit. Fire occurred infrequently in Douglas‐fir forest stands seral to mountain hemlock or silver fir, but fire frequency was much shorter than predicted by theory in other forest types. MFRIs within Douglas‐fir stands seral to western hemlock or grand fir ranged from 19 to 45 years, and MFRIs in stands seral to Douglas‐fir ranged from 6 to 11 years. There was little synchrony in fire occurrence or tree establishment across 16 sites separated by 4 km. The lack of synchrony in fire suggests that large, wind‐driven fire events that are often considered to be characteristic of coast Douglas‐fir forests were not an important driver of succession in our study area during the last ~400–500 years. Climate was more arid than normal during fire years in most forest types, but historical fire in stands seral to Douglas‐fir was strongly associated with antecedent moisture and less strongly associated with drought. We interpret the extraordinary tempo of fire we observed in stands seral to Douglas‐fir and the unique climate pattern associated with fire in these stands to be indicative of Indigenous fire stewardship. This study provides evidence of far more frequent historical fire in coast Douglas‐fir forests than assumed by managers or scientists—including some of the most frequent fire return intervals documented in the Pacific Northwest. We recommend additional research across the western Cascades to create a comprehensive account of historical fire in highly productive forests with significant cultural, economic, and ecological importance.

Fire is an inherently evolutionary process, even though much more emphasis has been given to ecological responses of plants and their associated communities to fire.Here, we synthesize contributions to a Special Feature entitled 'Fire as a dynamic ecological and evolutionary force' and place them in a broader context of fire research. Topics covered in this Special Feature include a perspective on the impacts of novel fire regimes on differential forest mortality, discussions on new approaches to investigate vegetation‐fire feedbacks and resulting plant syndromes, synthesis of fire impacts on plant–fungal interactions, and a meta‐analysis of arthropod community responses to fire.We conclude by suggesting pathways forward to better understand the ecological and evolutionary consequences of fire. These include developing ecological and evolutionary databases for fire ecology, integrating hierarchical genetic structure or phylogenetic structure, and developing new experimental frameworks that limit context‐dependent outcomes. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Plant fire syndromes are usually defined as combinations of fire response traits, the most common being resprouting (R) and seeding (S). Plant flammability (F), on the other hand, refers to a plant's effects on communities and ecosystems. Despite its important ecological and evolutionary implications, F has rarely been considered to define plant fire syndromes and, if so, usually separated from response syndromes.We propose a three‐dimensional model that combines R, S and F, encapsulating both plant response to fire regimes and the capacity to promote them. Each axis is divided into three possible standardized categories, reflecting low, medium and high values of each variable, with a total of 27 possible combinations of R, S and F.We hypothesized that different fire histories should be reflected in the position of species within the three‐dimensional space, and that this should help assess the importance of fire as an evolutionary force in determining R‐S‐F syndromes.To illustrate our approach, we compiled information on the fire syndromes of 24 dominant species of different growth forms from the Chaco seasonally dry forest of central Argentina, and we compared them to 33 species from different Mediterranean‐type climate ecosystems (MTCEs) of the world.Chaco and MTCEs species differed in the range (7 syndromes vs. 13 syndromes, respectively) and proportion of extreme syndromes (i.e. species with extreme values of R, S and/or F) representing 29% of species in the Chaco vs. 45% in the MTCEs.In addition, we explored the patterns of R, S and F of 4032 species from seven regions with contrasting fire histories, and found significantly higher frequencies of extreme values (predominantly high) of all three variables in MTCEs compared to the other regions, where intermediate and low values predominated, broadly supporting our general hypothesis.The proposed three‐dimensional approach should help standardize comparisons of fire syndromes across taxa, growth forms and regions with different fire histories. This will contribute to the understanding of the role of fire in the evolution of plant traits and assist vegetation modelling in the face of changes in fire regimes. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Much of the zooarchaeological research on early agricultural societies in North China focuses on long-term processes of animal domestication. The conventional idea of a simple transition from foraging wild species to farming domesticated ones has obscured ecological relationships that lie somewhere between the two. We argue that early farming strategies in North China may have resembled those of agricultural societies in North America where farmers managed landscapes to create deer habitat, which increased deer populations and facilitated hunting. Deer were one of the main sources of food, antlers, and hides for people in China for thousands of years. Shifting agriculture combined with deer hunting was a less intensive use of the landscape than the intensive agriculture that gradually replaced it. As domesticated cattle, sheep, and goats became more common in East Asia beginning around 5000 years ago, people had less need for the meat, bone, and antlers of deer. By the time Chinese historical texts were written, deer were largely confined to royal hunting parks in the densely populated agricultural centers of North China. A similar dynamic later played out in other regions of China. [ABSTRACT FROM AUTHOR]

Rising surface air temperatures, coupled with delays in the onset of austral summer rains and increased fuel load have amplified forest fire risk over southern Africa. This study investigates interactions between climate change and fire risk in South Africa's northern savanna biome. We employ the CCAM model to simulate the reference climate and project future forest fire risk on the savanna. An ensemble of six CMIP5 GCMs were downscaled to 8 km to project climate change in the far-future (2080 to 2099) under RCP8.5 emission scenario. The models were validated using ERA5-Land reanalyses whilst future projections focused on the 10th, 50th and 90th percentiles. The frequency of high fire risk days was calculated using a McArthur Forest Fire Danger Index (FFDI) which links meteorological variables to fire danger. The ensemble simulated widespread temperature rises of between 4.5 and 6 °C across the savanna, whilst rainfall is projected to decline by up to 20 mm/month, with corresponding decreases in minimum relative humidity. Heat wave days are projected to increase to above 8 days per annum, whilst soil moisture deficiency increases by above 50 mm on the savanna. Consequently, mean annual high fire danger days are projected to reach a peak frequency of 25 days in October, with an autumnal secondary peak. Spatially, greater increases in high FFDI days were projected over the western savanna extending toward neighbouring Botswana. This study contributes to understanding fire risk under unprecedented temperature rises which appear to be modulating fire intensity in the study region. [ABSTRACT FROM AUTHOR]

Wildfire is an integral component of the terrestrial ecosystem that plays a significant role in regulating the vegetation cover. The paleofire records stored in lacustrine, peat, or marine sedimentary deposits along with environmental proxy records provide temporal information on fire activity and contemporary climatic conditions on a regional scale. A ~2.8m long peat sedimentary profile from Stagmo, Indus Valley, Ladakh Himalaya was examined for sedimentology and charcoal microfossil contents to investigate fire characteristics and reconstruct wildfires which are compared with paleoclimatic changes and past human activities to assess their significance in biomass burning. Charcoal count (CC) analysis provides a suitable method for investigating climatic and vegetation changes with human intervention when no direct evidence is available in the Late-Holocene Trans Himalaya records. The results bring new insight into the interaction between vegetation, fire, and human activity in the Ladakh Himalaya during the past ~2.8 cal kyr BP. An event characterized by high CC at ~2.8 cal kyr BP is distinct from the whole sequence and cannot easily be explained as only the result of a climatic event. This first high charcoal count phase (2.81–2.55 cal kyr BP) could be a natural response to the expansion of forest and dense vegetation with human management interruption. This paleo wildfire event likely corresponds with the time of the Tibetan Plateau's immediate human occupation. In the second phase, a relatively low charcoal count (1.65–1.54 cal kyr BP) is supported by the high fuel availability during a transitional phase. The third phase of wildfire reconstruction in Ladakh Himalaya is identified at ~1.38 cal kyr BP. This phase can be correlated with the intensified Indian Summer Monsoon (ISM) advancing to Trans-Himalaya leading to increased human settlement in the region. [ABSTRACT FROM AUTHOR]

Multiproxy reconstructions of fire regimes in forest ecosystems can provide a clearer understanding of past fire activity and circumvent some limitations of single proxy reconstructions. While inferring fire history from scars in trees is the most precise method to reconstruct temporal fire patterns, this method is limited in Araucaria araucana forests by rot after fire injuries, successive fires that destroy the evidence and the prohibition of sample extraction from living Araucaria trees. In this context, dendrochemical studies in Araucaria trees and charcoal analysis from sediment cores can complement and extend the time perspective of the fire history in the relictual Araucaria-Nothofagus forests of the coastal range. We used dendrochemical, fire scar and charcoal records from the Nahuelbuta Coastal Range (37.8° S; 73° W) spanning the last 1000 years to reconstruct the fire history. The results indicate that periods with higher fire activity occurred between 1400 and 1650 AD. Long-term changes in the fire regime are related to increased climate variability over the last 1000 years, and especially with the arrival of settlers to the area after 1860 CE. The most severe fire events in the Nothofagus and Araucaria forests occurred when suitable fire-prone conditions were superimposed with high human densities. [ABSTRACT FROM AUTHOR]

The historical role of fire in sagebrush (Artemisia tridentata) landscapes remains poorly understood, yet is important to inform management and conservation of obligate species such as the threatened Gunnison Sage‐grouse (GUSG; Centrocercus minimus). We reconstructed fire histories from tree‐ring fire scars at sagebrush–forest ecotones (10 sites, 111 trees) to better understand the role of fire in sagebrush landscapes of the Upper Gunnison Basin (UGB), Colorado, and how fire may have changed following Euro‐American settlement. We assessed likely influences of historical fire by surveying plant composition and structure at 100 sagebrush sites with and without recent (2001–2020) fires. Tree‐ring fire scars revealed a history of repeated low‐severity fire at sagebrush–forest ecotones until 1892, followed by over a century without fire. Between 1684 and 1892, the mean fire interval (MFI) among sites averaged 49.6 years (ranging from 18.2 to 119 years). Fire over this period occurred synchronously at two or more sites on average every 23.6 years, potentially indicative of spread between sites. Most (70%) of the historical fires burned in the early growing season, consistent with times of strong wind. Recent burns exhibited reductions in sagebrush cover (5% vs. 25% in unburned sites) and concomitant increases in herbaceous cover (55% vs. 40%). These differences declined over time but persisted for at least two decades. Burned sites were dominated by native perennial grasses, forbs, and resprouting shrub species. Historically, such openings may have served as seasonal GUSG habitat. Our results indicate that parts of the UGB sagebrush landscapes were characterized historically by frequent fire and dynamic vegetation mosaics that included open, grassy patches. These findings support the use of prescribed fire to restore and maintain this ecological process and vegetation heterogeneity. However, the contemporary context for fire has changed and now includes substantially reduced, Endangered Species Act (ESA)‐listed GUSG populations, increased risk of non‐native plant invasion, and climate warming. These circumstances highlight new risks, information needs, and opportunities for key knowledge co‐production via management–research partnerships. [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.)

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.)

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.)

Fire is an integral part of southern African savannas, but despite being well-studied, complex relationships among fire, humans, climate and ecological systems remain poorly understood across much of the region. Analyses that provide information on fire trends in diverse regional contexts are essential for informing fire management and monitoring change. Harmonic seasonal patterns, linear time-series trends and breakpoints in fire occurrence (BFAST) were analysed for 2001–2018 in Botswana using remotely sensed fire occurrence measurements. Regional classification schemes were organized by human land-use, annual precipitation zones and vegetation communities. At the regional scale, mean annual precipitation, land-use and vegetation type influenced fire occurrence magnitude. Seasonality and variability were most clearly organized according to mean annual precipitation. Variability in seasonal and long-term fire trends were observed across the different classification schemes apart from mean annual precipitation zones above 600 mm. The methodology used effectively identified key differences in fire variability across regional classification schemes. However, the spatial resolution and classification scheme may be less effective for human land use and small fires. Overall, MODIS fire data analysed with BFAST is a promising and accessible method for analysing regional savanna fire regimes. [ABSTRACT FROM AUTHOR]

Foreseeing faunal responses to fire is a challenging issue, due to the context-dependent effects of fire. Although previous studies have registered declines in the abundance of vertebrates, particularly small mammals, following changes in fire regimes, the mechanisms driving these changes are still poorly understood. Hence, we investigated the effects of a severe fire on the abundance, survival, and body condition of a semelparous didelphid (Gracilinanus agilis) inhabiting one of the largest Cerrado remnants in the Triangulo Mineiro region. Using a before–after approach, G. agilis individuals were monitored from 2011 to 2016 through monthly live-trapping sessions. Gracilinanus agilis population followed repeated oscillations every year, with marked declines in abundance after the mating season, irrespective of the 2014´s fire. Although fire reduced population size, it did not lead to a precipitous decline in G. agilis abundance. Survival rates were not affected by fire; instead were determined by the sex and breeding status of individuals. The fire caused a decrease only in female body condition, which resulted in a reduced length of the breeding season and a lower number of juveniles following the disturbance. Our results support the contention that fire affects small mammals indirectly, mainly through its effects on recruitment. The observed weak fire effects on the population level seem to be associated with the less sensitive dynamics of fast-living species. Hence, we emphasize the need to investigate the mechanisms driving faunal responses to fire, especially considering the recent changes in fire regimes and the role of life histories on species responses. [ABSTRACT FROM AUTHOR]

Abstract The historical role of fire in sagebrush (Artemisia tridentata) landscapes remains poorly understood, yet is important to inform management and conservation of obligate species such as the threatened Gunnison Sage‐grouse (GUSG; Centrocercus minimus). We reconstructed fire histories from tree‐ring fire scars at sagebrush–forest ecotones (10 sites, 111 trees) to better understand the role of fire in sagebrush landscapes of the Upper Gunnison Basin (UGB), Colorado, and how fire may have changed following Euro‐American settlement. We assessed likely influences of historical fire by surveying plant composition and structure at 100 sagebrush sites with and without recent (2001–2020) fires. Tree‐ring fire scars revealed a history of repeated low‐severity fire at sagebrush–forest ecotones until 1892, followed by over a century without fire. Between 1684 and 1892, the mean fire interval (MFI) among sites averaged 49.6 years (ranging from 18.2 to 119 years). Fire over this period occurred synchronously at two or more sites on average every 23.6 years, potentially indicative of spread between sites. Most (70%) of the historical fires burned in the early growing season, consistent with times of strong wind. Recent burns exhibited reductions in sagebrush cover (5% vs. 25% in unburned sites) and concomitant increases in herbaceous cover (55% vs. 40%). These differences declined over time but persisted for at least two decades. Burned sites were dominated by native perennial grasses, forbs, and resprouting shrub species. Historically, such openings may have served as seasonal GUSG habitat. Our results indicate that parts of the UGB sagebrush landscapes were characterized historically by frequent fire and dynamic vegetation mosaics that included open, grassy patches. These findings support the use of prescribed fire to restore and maintain this ecological process and vegetation heterogeneity. However, the contemporary context for fire has changed and now includes substantially reduced, Endangered Species Act (ESA)‐listed GUSG populations, increased risk of non‐native plant invasion, and climate warming. These circumstances highlight new risks, information needs, and opportunities for key knowledge co‐production via management–research partnerships.

The fate of natural populations is mediated by complex interactions among vital rates, which can vary within and among years. Although the effects of random, among‐year variation in vital rates have been studied extensively, relatively little is known about how periodic, nonrandom variation in vital rates affects populations. This knowledge gap is potentially alarming as global environmental change is projected to alter common periodic variations, such as seasonality. We investigated the effects of changes in vital‐rate periodicity on populations of three species representing different forms of adaptation to periodic environments: the yellow‐bellied marmot (Marmota flaviventer), adapted to strong seasonality in snowfall; the meerkat (Suricata suricatta), adapted to inter‐annual stochasticity as well as seasonal patterns in rainfall; and the dewy pine (Drosophyllum lusitanicum), adapted to fire regimes and periodic post‐fire habitat succession. To assess how changes in periodicity affect population growth, we parameterized periodic matrix population models and projected population dynamics under different scenarios of perturbations in the strength of vital‐rate periodicity. We assessed the effects of such perturbations on various metrics describing population dynamics, including the stochastic growth rate, log λS. Overall, perturbing the strength of periodicity had strong effects on population dynamics in all three study species. For the marmots, log λS decreased with increased seasonal differences in adult survival. For the meerkats, density dependence buffered the effects of perturbations of periodicity on log λS. Finally, dewy pines were negatively affected by changes in natural post‐fire succession under stochastic or periodic fire regimes with fires occurring every 30 years, but were buffered by density dependence from such changes under presumed more frequent fires or large‐scale disturbances. We show that changes in the strength of vital‐rate periodicity can have diverse but strong effects on population dynamics across different life histories. Populations buffered from inter‐annual vital‐rate variation can be affected substantially by changes in environmentally driven vital‐rate periodic patterns; however, the effects of such changes can be masked in analyses focusing on inter‐annual variation. As most ecosystems are affected by periodic variations in the environment such as seasonality, assessing their contributions to population viability for future global‐change research is crucial. [ABSTRACT FROM AUTHOR]

Fire is an important disturbance factor in shrublands, grasslands, and savannas. It alters the habitat of a multitude of species and, under natural dynamics, is a major determinant of landscape vegetation patterns. Here, we evaluate the effects of different wildfire regimes on the abundance of sun spiders in the Cerrado-Pantanal ecotone. To study how different fire regimes affect the number of individual sun spiders, we considered the frequency of fire occurrences in the last 20 years and classified locations as high frequency or low frequency. We also classified the time of the last fire in 2020 as occurring in the first or second half of the year. In addition, we compared the number of individual sun spiders before and after fire. We found no effects of fire frequency and period when the fire occurred in 2020, but the number of individual sun spiders was higher after wildfires. Although ground-dwelling are considered fire sensitive, some can employ strategies to tolerate fire so that they are able to not only survive, but also reproduce in fire-prone landscapes. Thus, we suggest that sun spiders are resilient, can explore sites under different fire regimes, and can be considered pyrophilous species. [ABSTRACT FROM AUTHOR]

Fire regimes in Mediterranean countries have been shifting in recent decades, including changes in wildfire size and frequency. We sought to describe changes in fire regimes across two periods (1975–1995 and 1996–2018) in a fire-prone region of central Portugal, explore the relationships between these regimes and territorial features, and check whether these associations persisted across periods. Two independent indicators of fire regimes were determined at parish level: fire incidence and burn concentration. Most parishes presented higher values of both indicators in the second period. Higher values of fire incidence were associated with lower population densities, lower proportions of farmland areas and higher proportions of natural vegetation. Higher levels of burn concentration were associated with smaller areas of farmland and natural vegetation. These associations differed across periods, reflecting contrasting climatic and socio-economic contexts. Keeping 40% of a parish territory covered by farmland was effective to buffer the increased wildfire risks associated with different management and climate contexts. The effectiveness of higher population densities in keeping fire incidence low decreased in the last decades. The results can improve the knowledge on the temporal evolution of fire regimes and their conditioning factors, providing contributions for spatial planning and forest/wildfire management policies. [ABSTRACT FROM AUTHOR]

The Great Sandy National Park [K'gari (Fraser Island) and Cooloola] contains the largest subtropical patterned fen complexes in the world. These globally significant, groundwater-dependent ecosystems have been previously studied in relatively undisturbed areas on K'gari and were suggested to be resilient to changes in hydrology, sea level and wildfires. The Rainbow Beach patterned fens are under-studied systems thought to be formed in local perched aquifers. The palaeoenvironmental conditions required for the formation and continuation of these peatlands, and how they react to changes in hydroclimate, sea level and human activities are uncertain. We attempt to resolve this ambiguity using proxies for vegetation and environmental changes over the last ~12,770 cal yr BP from a sediment core located in the Rainbow Beach patterned fen complex. We infer the formation of an aquitard layer and Empodisma minus mire development at ~12,770 cal yr BP, with conditions conducive for patterning ~12,000–10,000 cal yr BP. Paludification occurred in the early Holocene, coincident with increased sea levels, which expanded the mire inland. Increased salt marsh taxa during this period coincides with decreased E. minus values, while further peatland development occurred ~4200 cal yr BP, suggesting that marine influences greatly effect these coastal peatlands. Evidence of vegetation thickening associated with post-European fire suppression was observed. Compared to those on K'gari, the Rainbow Beach complex appears to have initiated through different processes and show greater sensitivity to changes in sea levels. Therefore, subtropical patterned fens should be assessed independently to identify individual trajectories and sensitivities. [ABSTRACT FROM AUTHOR]

Understanding the ecological role of fire in forests is essential for proper management and conservation programs. The objectives of this study were: (1) to reconstruct the history of fires in a temperate forest in Sierra Madre Occidental; and (2) to interpret the impacts of fire and climate on forest structure. Sixty tree cross-sections with fire scars were analyzed, and descriptive statistics of fire history were generated. Additionally, growth cores were analyzed, and the ages of trees of different diameter categories were calculated. The synchrony between fire history and tree establishment was determined, and precipitation and Palmer Drought Severity Index (PDSI) values were correlated with the number of trees established per year. The presence of 137 fire scars was determined, which allowed the reconstruction of 41 fire events over the period 1855–2019; however, only the period 1940–2015 was used to compare tree recruitment, as tree establishment was detected in this period. The mean fire interval (MFI) was 2.28 years in general, and 12.17 years for extensive fires. As regards vegetation, a continuous recruitment pattern was observed, typical of a frequent low-intensity fire regime, although peak regeneration occurred after extensive fires. The correlation analysis showed that the number of trees established per year was influenced by the wet conditions that occurred in December of the previous year and the dry conditions in September and October of the previous year. This finding demonstrates the historical influence of fire and climate on the structure of the current stand in the study area. Therefore, the present study highlights the importance of including fire in forest management programs, considering the natural fire regime to which the species in this ecosystem are already adapted. [ABSTRACT FROM AUTHOR]

Narratives of landscape degradation are often linked to unsustainable fire use by local communities. Madagascar is a case in point: the island is considered globally exceptional, with its remarkable endemic biodiversity viewed as threatened by unsustainable anthropogenic fire. Yet, fire regimes on Madagascar have not been empirically characterised or globally contextualised. Here, we contribute a comparative approach to determining relationships between regional fire regimes and global patterns and trends, applied to Madagascar using MODIS remote sensing data (2003–2019). Rather than a global exception, we show that Madagascar's fire regimes are similar to 88% of tropical burned area with shared climate and vegetation characteristics, and can be considered a microcosm of most tropical fire regimes. From 2003–2019, landscape‐scale fire declined across tropical grassy biomes (17%–44% excluding Madagascar), and on Madagascar at a relatively fast rate (36%–46%). Thus, high tree loss anomalies on the island (1.25–4.77× the tropical average) were not explained by any general expansion of landscape‐scale fire in grassy biomes. Rather, tree loss anomalies centred in forests, and could not be explained by landscape‐scale fire escaping from savannas into forests. Unexpectedly, the highest tree loss anomalies on Madagascar (4.77×) occurred in environments without landscape‐scale fire, where the role of small‐scale fires (<21 h [0.21 km2]) is unknown. While landscape‐scale fire declined across tropical grassy biomes, trends in tropical forests reflected important differences among regions, indicating a need to better understand regional variation in the anthropogenic drivers of forest loss and fire risk. Our new understanding of Madagascar's fire regimes offers two lessons with global implications: first, landscape‐scale fire is declining across tropical grassy biomes and does not explain high tree loss anomalies on Madagascar. Second, landscape‐scale fire is not uniformly associated with tropical forest loss, indicating a need for socio‐ecological context in framing new narratives of fire and ecosystem degradation. [ABSTRACT FROM AUTHOR]

New forests can bring many benefits; however, public concern over wildfires can create a dilemma for restoration ecologists, managers, and policy makers advocating for forestation. In southern montane New Zealand, destocking following pastoral tenure review and forestation incentives have resulted in an increase in woody vegetation, raising concerns over fire risk. We used abundance‐weighted community flammability metrics to investigate changes in the flammability of montane grassland within Mahu Whenua Ecosanctuary following destocking, and the relative flammability of woody communities likely to establish naturally in this area. While woody species cover increased following destocking, a decrease in highly combustible graminoids and shrubs, and increased abundance of non‐flammable herbaceous species meant community flammability metrics reduced or showed no change. Woody communities that could potentially develop in the area varied substantially in structure and composition. Open, species‐rich, shrublands showed lower flammability metrics for both understorey and canopy than mixed dense shrubland/forests or species‐poor beech (Nothofagaceae) forests. For active forestation projects where fire is undesirable, a low‐flammability herbaceous understorey can reduce fire risk. Where desirable forest species are highly combustible but fire‐intolerant, e.g. New Zealand beech, fire risk could be reduced by maintaining buffer zones of low‐flammability vegetation or applying planting strategies such as nucleation that accelerate the development of closed canopy forest patches more likely to have moisture‐retentive ground layers. However, in historically burnt landscapes, additional information will be needed to define the wider pool of low‐flammability species appropriate for forestation programs. [ABSTRACT FROM AUTHOR]