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Contemporary fire regimes are recognized as a key threatening process for relatively immobile vertebrates and narrowly dispersing obligate seeder plant taxa in fire‐prone Australian savannas. Here, we assess the efficacy of proposed ecological performance threshold metrics for evaluating the current state of fire management for biodiversity conservation outcomes in Australia's premier, and best publicly funded savanna reserve, Kakadu National Park. The assessment draws on available data describing Landsat‐scale fire mapping over the period 1997–2015, habitat mapping, and mostly modeled responses of vegetation and faunal attributes. Despite conceptual and technical issues associated with various proposed performance thresholds and mapping products, the assessment demonstrates significant challenges with the current state of the reserve's fire management program. For example, by the end of 2015 it was observed that just 6% of woodland habitat in lowland and 23% in upland situations had remained unburnt for longer than three years and 98% of mapped fires in lowland and 87% in upland habitats were >1 km2 in extent. Of 14 assessed performance threshold metrics, two were within acceptable thresholds at the end of 2015, and none had improved materially over the decadal assessment period. Given substantial resources evidently required to deliver effective, seasonally intensive, fine‐grained adaptive fire management for biodiversity conservation outcomes in fire‐prone Australian savannas, we suggest that alternative resourcing opportunities through market‐based savanna burning greenhouse gas emissions abatement projects need to be explored.

Savanna sites are idealized as exhibiting a demographic “bottleneck” physiognomy comprising a lower stratum of abundant resprouting persistent “juveniles” (albeit of indeterminate age), a mid‐stratum comprising relatively few released “saplings,” and a canopy‐layer cohort of “adults.” The magnitude and frequency of disturbance is considered to influence the critical transition from juvenile into adult phases. Under fire‐prone Australian savanna conditions, an extensive suite of both observational and manipulative studies have explored the responses of tree recruitment to fire disturbances. These studies oftentimes have produced seemingly highly disparate responses, particularly with respect to the differential responses of relatively fast‐growing eucalypts versus non‐eucalypts under different fire regime, and overstory competition, conditions. This study contrasts the responses of tree recruitment height classes to (1) the effects of total canopy removal from severe Cyclone Monica in 2006 over a subsequent 10‐yr period, (2) with observations from long‐term monitoring sites under relatively stable overstory conditions at Litchfield National Park over a six‐year period, (3) under ambient, frequent fire occurrence (mean > 0.5 fires/yr) at both locales including relatively severe late dry season fires. Recruitment at both study sites was represented mostly by resprouting, clonally reproducing juvenile trees <2 m tall, around half of which died over respective assessment periods. At post‐cyclone assessment plots, there was substantial release of eucalypts, including within the first five years, into the >5 m height class, with negligible corresponding release of non‐eucalypts. At Litchfield plots, there was negligible release of both eucalypts and non‐eucalypts. In discussion, we contrast these results with findings from relevant regional studies. We contend that collective disparate observations feasibly can be reconciled as reflecting significant interactions between fire regime characteristics and variable site overstory competition effects, such that the rate of recruitment of fast‐growing savanna eucalypt individuals into the midstory is relatively independent of the fire regime, but is significantly regulated by resource competition interactions especially with the overstory, whereas recruitment of non‐eucalypts is relatively independent of overstory competitive effects, but is suppressed under fire regimes dominated by frequent, especially severe fires.

Aim: Building on a substantial literature addressing the fire responses of woody plants, particularly under mediterranean climates, we assess the extent to which fire persistence traits can be used to predict vegetation responses to fire regime changes in fire-prone arid and savanna landscape settings. Location: Australia, applying data from arid central to monsoonal northern regions (11–26° S, 129–138° E). Methods: With reference to a substantial sub-continental floristics dataset, we first assigned the fire response (obligate seeder, resprouter) and seedbank persistence (transient, dormant) of rapid and longer-maturing (> 3 years) woody taxa. Using logistic regression, we then modelled the proportions of taxa possessing these traits as a function of mean annual rainfall (highly correlated with fire frequency) and terrain roughness (a measure of topographic variability) in 0.25° x 0.25° and 1° x 1° grid cells. Separate assessments were undertaken with datasets for 1264 sclerophyll and 236 rain forest taxa. Results: This woody flora is characterized by taxa exhibiting mostly resprouting and dormant seedbank traits that promote site persistence. While numbers of obligate seeder and resprouter taxa were related positively to both rainfall and roughness, the relative abundance of both sclerophyll and rain forest obligate seeders decreased significantly with rainfall. The relative abundance of sclerophyll (especially long-lived) obligate seeders alone increased with topographic roughness. The proportion of taxa with transient seedbanks increased with rainfall in resprouters generally, and in rain forest obligate seeders alone. Main conclusions: We find that resprouters are favoured on more productive, fire-prone sites, and obligate seeders are favoured in less productive, more fireprotected settings. Seedbank persistence responses are more variable. These findings concur generally with theoretical constructs, and support comparable assessments in Australian and other fire-prone systems ranging from mediterranean to boreal environments. Our observations illustrate that resprouting and obligate seeding syndromes, but not necessarily seedbank persistence, are useful predictors of vegetation responses to changing fire regime conditions at large landscape scales.

Ecologists have long sought to understand the factors controlling the structure of savanna vegetation. Using data from 2154 sites in savannas across Africa, Australia, and South America, we found that increasing moisture availability drives increases in fire and tree basal area, whereas fire reduces tree basal area. However, among continents, the magnitude of these effects varied substantially, so that a single model cannot adequately represent savanna woody biomass across these regions. Historical and environmental differences drive the regional variation in the functional relationships between woody vegetation, fire, and climate. These same differences will determine the regional responses of vegetation to future climates, with implications for global carbon stocks.

Aim: Comparative analyses of fire regimes at large geographical scales can potentially identify ecological and climatic controls of fire. Here we describe Australia's broad fire regimes, and explore interrelationships and trade-offs between fire regime components. We postulate that fire regime patterns will be governed by trade-offs between moisture, productivity, fire frequency and fire intensity. Location: Australia. Methods: We reclassified a vegetation map of Australia, defining classes based on typical fuel and fire types. Classes were intersected with a climate classification to derive a map of 'fire regime niches'. Using expert elicitation and a literature search, we validated each niche and characterized typical and extreme fire intensities and return intervals. Satellite-derived active fire detections were used to determine seasonal patterns of fire activity. Results: Fire regime characteristics are closely related to the latitudinal gradient in summer monsoon activity. Frequent low-intensity fires occur in the monsoonal north, and infrequent, high-intensity fires in the temperate south, demonstrating a trade-off between frequency and intensity: that is, very high-intensity fires are only associated with very low-frequency fire regimes in the high biomass eucalypt forests of southern Australia. While these forests occasionally experience extremely intense fires (> 50,000 kW m -1 ), such regimes are exceptional, with most of the continent dominated by grass fuels, typically burning with lower intensity (< 5000 kW m -1 ). Main conclusions: Australia's fire regimes exhibit a coherent pattern of frequent, grass-fuelled fires in many differing vegetation types. While eucalypts are a quintessential Australian entity, their contribution as a dominant driver of high-intensity fire regimes, via their litter and bark fuels, is restricted to the forests of the continent's southern and eastern extremities. Our analysis suggests that the foremost driver of fire regimes at the continental scale is not productivity, as postulated conceptually, but the latitudinal gradient in summer monsoon rainfall activity.

The Kere is a recurrent famine occurring in the south of Madagascar that emerged substantively in the 1930s. Each major event claims thousands of lives and keeps many in a cycle of impoverishment, despite the existence of various aid-based responses. This assessment presents qualitative research exploring two Kere-affected communities’ experiences of the phenomenon. Through focus group discussions, we learn that the Kere is a complex social-ecological disaster, compounded by an intricate chain of causation and impacts. Seeking a deep understanding of affected peoples’ perceptions and experience of the phenomenon, this paper challenges the idea that the Kere is a famine caused by recurring drought that can only be solved with provision of water and aid-based solutions. Based on community views and research literature, and the application of Ostrom’s social-ecological systems framework, we demonstrate that the Kere is a phenomenon compounded by multiple interacting, debilitating factors including deforestation, drought, pests and diseases, food insecurity, extreme poverty, lawlessness, and political malaise; thus, solutions require a comprehensive, sustained, holistic response.

Carbon markets afford potentially useful opportunities for supporting socially and environmentally sustainable land management programs but, to date, have been little applied in globally significant fire-prone savanna settings. While fire is intrinsic to regulating the composition, structure and dynamics of savanna systems, in north Australian savannas frequent and extensive late dry season wildfires incur significant environmental, production and social impacts. Here we assess the potential of market-based savanna burning greenhouse gas emissions abatement and allied carbon biosequestration projects to deliver compatible environmental and broader socio-economic benefits in a highly biodiverse north Australian setting. Drawing on extensive regional ecological knowledge of fire regime effects on fire-vulnerable taxa and communities, we compare three fire regime metrics (seasonal fire frequency, proportion of long-unburnt vegetation, fire patch-size distribution) over a 15-year period for three national parks with an indigenously (Aboriginal) owned and managed market-based emissions abatement enterprise. Our assessment indicates improved fire management outcomes under the emissions abatement program, and mostly little change or declining outcomes on the parks. We attribute improved outcomes and putative biodiversity benefits under the abatement program to enhanced strategic management made possible by the market-based mitigation arrangement. For these same sites we estimate quanta of carbon credits that could be delivered under realistic enhanced fire management practice, using currently available and developing accredited Australian savanna burning accounting methods. We conclude that, in appropriate situations, market-based savanna burning activities can provide transformative climate change mitigation, ecosystem health, and community benefits in northern Australia, and, despite significant challenges, potentially in other fire-prone savanna settings.

Despite calls by various international agencies, considerable work is still required to understand and incorporate the importance of earth’s ecosystems for informing public policies. Savannas comprise nearly one third of global terrestrial ecosystems and support many local and Indigenous communities, but the value of their ecosystem services (ES) is insufficiently understood. This study proposes an integrated ES valuation framework and applies it to assess ES for an Indigenous savanna estate in northern Australia, describing how capabilities along with biophysical and socio-cultural ES benefits play a vital role for peoples’ wellbeing. We estimated the monetary value of ES by applying a conventional Basic Value Transfer (BVT) method for biophysical benefits (USD 84 M y−1), and a wellbeing approach for valuing socio-cultural benefits and capabilities (USD 4 M y−1). The latter offers a relatively nominal estimate but underscores the importance of including peoples’ capabilities in order to demonstrate wellbeing benefits for Indigenous people who regularly visit and utilize their lands. We explore two scenarios, Business as Usual (pastoral land use) and ES-based economies (implying customary land use, particularly through fire management) to project plausible broader benefits for the community over a longer term. This research describes how inclusion of Indigenous peoples’ capabilities and socio-cultural values are critical for ES assessments, and indicates that an integrated approach is essential for appropriately informing local, regional and global development policies.

Aim Fire is a key agent in savanna systems, yet the capacity to predict fine‐grained population phenomena under variable fire regime conditions at landscape scales is a daunting challenge. Given mounting evidence for significant impacts of fire on vulnerable biodiversity elements in north Australian savannas over recent decades, we assess: (1) the trajectory of fire‐sensitive vegetation elements within a particularly biodiverse savanna mosaic based on long‐term monitoring and spatial modelling; (2) the broader implications for northern Australia; and (3) the applicability of the methodological approach to other fire‐prone settings. Location Arnhem Plateau, northern Australia. Methods We apply data from long‐term vegetation monitoring plots included within Kakadu National Park to derive statistical models describing the responses of structure and floristic attributes to 15 years of ambient (non‐experimental) fire regime treatments. For a broader 28,000 km2 region, we apply significant models to spatial assessment of the effects of modern fire regimes (1995–2009) on diagnostic closed forest, savanna and shrubland heath attributes. Results Significant models included the effects of severe fires on large stems of the closed forest dominant Allosyncarpia ternata, stem densities of the widespread savanna coniferous obligate seeder Callitris intratropica, and fire frequency and related fire interval parameters on numbers of obligate seeder taxa characteristic of shrubland heaths. No significant relationships were observed between fire regime and eucalypt and non‐eucalypt adult tree components of savanna. Spatial application of significant models illustrates that more than half of the regional closed forest perimeters, savanna and shrubland habitats experienced deleterious fire regimes over the study period, except in very dissected terrain. Main conclusions While north Australia’s relatively unmodified mesic savannas may appear structurally intact and healthy, this study provides compelling evidence that fire‐sensitive vegetation elements embedded within the savanna mosaic are in decline under present‐day fire regimes. These observations have broader implications for analogous savanna mosaics across northern Australia, and support complementary findings of the contributory role of fire regimes in the demise of small mammal fauna. The methodological approach has application in other fire‐prone settings, but is reliant on significant long‐term infrastructure resourcing.

In the context of Australia's developing carbon economy, fire management helps to abate emissions of greenhouse gases and is an important means of generating carbon credits. The vast high-rainfall savannas of northern Australia are one of the world's most flammable landscapes. Management of fires in this region has the potential to assist with meeting emissions reduction targets, as well as conserving biodiversity and providing employment for Indigenous people in remote parts of Australia's north. This comprehensive volume brings together recent research from northern Australian savannas to provide an internationally relevant case study for applying greenhouse gas accounting methodologies to the practice of fire management. It provides scientific arguments for enlarging the area of fire-prone land managed for emissions abatement. The book also charts the progress towards development of a savanna fire bio-sequestration methodology. The future of integrated approaches to emissions abatement and bio-sequestration is also discussed.