scholarly journals Indigenous impacts on north Australian savanna fire regimes over the Holocene

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Christopher M. Wurster ◽  
Cassandra Rowe ◽  
Costijn Zwart ◽  
Dirk Sachse ◽  
Vladimir Levchenko ◽  
...  
Keyword(s):  
Late Holocene ◽  
Fire Management ◽  
Southern Oscillation ◽  
Fire Regimes ◽  
Fire Intensity ◽  
Northern Australia ◽  
Tropical Savannas ◽  
Fire Dynamics ◽  
Proxy Records ◽  
Ecological Feedbacks

AbstractFire is an essential component of tropical savannas, driving key ecological feedbacks and functions. Indigenous manipulation of fire has been practiced for tens of millennia in Australian savannas, and there is a renewed interest in understanding the effects of anthropogenic burning on savanna systems. However, separating the impacts of natural and human fire regimes on millennial timescales remains difficult. Here we show using palynological and isotope geochemical proxy records from a rare permanent water body in Northern Australia that vegetation, climate, and fire dynamics were intimately linked over the early to mid-Holocene. As the El Niño/Southern Oscillation (ENSO) intensified during the late Holocene, a decoupling occurred between fire intensity and frequency, landscape vegetation, and the source of vegetation burnt. We infer from this decoupling, that indigenous fire management began or intensified at around 3 cal kyr BP, possibly as a response to ENSO related climate variability. Indigenous fire management reduced fire intensity and targeted understory tropical grasses, enabling woody thickening to continue in a drying climate.

Optimal Fire Regimes for Soil Carbon Storage in Tropical Savannas of Northern Australia

Ecosystems ◽  
2011 ◽  
Vol 14 (3) ◽  
pp. 503-518 ◽  
Author(s):  
Anna E. Richards ◽  
Garry D. Cook ◽  
Brian T. Lynch
Keyword(s):  
Soil Carbon ◽  
Carbon Storage ◽  
Fire Regimes ◽  
Northern Australia ◽  
Soil Carbon Storage ◽  
Tropical Savannas

scholarly journals Multiproxy Holocene Fire Records From the Tropical Savannas of Northern Cape York Peninsula, Queensland, Australia

2021 ◽  
Vol 9 ◽  
Author(s):  
Emma Rehn ◽  
Cassandra Rowe ◽  
Sean Ulm ◽  
Patricia Gadd ◽  
Atun Zawadzki ◽  
...  
Keyword(s):  
Fire Management ◽  
Fire Regimes ◽  
Fire Intensity ◽  
Methodological Innovation ◽  
Management Planning ◽  
Indigenous Management ◽  
Northern Cape ◽  
Cape York

Paleoecology has demonstrated potential to inform current and future land management by providing long-term baselines for fire regimes, over thousands of years covering past periods of lower/higher rainfall and temperatures. To extend this potential, more work is required for methodological innovation able to generate nuanced, relevant and clearly interpretable results. This paper presents records from Cape York Peninsula, Queensland, Australia, as a case study where fire management is an important but socially complex modern management issue, and where palaeofire records are limited. Two new multiproxy palaeofire records are presented from Sanamere Lagoon (8,150–6,600 cal BP) and Big Willum Swamp (3,900 cal BP to present). These records combine existing methods to investigate fire occurrence, vegetation types, and relative fire intensity. Results presented here demonstrate a diversity of fire histories at different sites across Cape York Peninsula, highlighting the need for finer scale palaeofire research. Future fire management planning on Cape York Peninsula must take into account the thousands of years of active Indigenous management and this understanding can be further informed by paleoecological research.

scholarly journals Anthropogenic Fires in West African Landscapes: A Spatially Explicit Model Perspective of Humanized Savannas

Fire ◽  
2020 ◽  
Vol 3 (4) ◽  
pp. 62
Author(s):  
Sébastien Caillault ◽  
Paul Laris ◽  
Cyril Fleurant ◽  
Daniel Delahaye ◽  
Aziz Ballouche
Keyword(s):  
Management Practices ◽  
Fire Management ◽  
Fire Regimes ◽  
Blind Spot ◽  
Global Scale ◽  
Human Dimensions ◽  
Management Scenarios ◽  
Fire Dynamics ◽  
Anthropogenic Fire ◽  
The Impact

Fire regimes are important components of environmental dynamics, but our understanding of them is limited. Despite recent advances in the methodologies used to remotely sense and map fires and burned areas and new case studies that shed light on local fire use and management practices, the scientific community still has much to learn about anthropogenic fire regimes. We identify two areas for improvement: first, the fine-scale heterogeneity of fire dynamics for specific regions is often masked by global-scale approaches, and second, barriers between the disciplines focusing on fire impacts hamper the development of knowledge of the human dimensions of fire regimes. To address the “blind spot” that these limitations create, we present a simple dynamic model of fire ignition in savanna systems. The aim is to connect the local and global scales of fire regimes by focusing on human fire management (anthropogenic fire). Our dynamical model is based on a study area in Western Burkina Faso and integrates biophysical elements (climate and soil data), land cover, and fire management scenarios based on field surveys. The simulation results offer contrasting views of the impact of local fire management practices on regional fire regimes observed in savannas. Fire density and frequency are local variables that clearly change the fire regimes despite a complex and constrained biophysical system. This experience, drawing from fieldwork and modelling, may be a way to integrate some key aspects of anthropogenic fire research in savanna systems.

scholarly journals A late-Holocene record of coastal wetland development and fire regimes in tropical northern Australia

The Holocene ◽  
2020 ◽  
Vol 30 (10) ◽  
pp. 1379-1390 ◽  
Author(s):  
Lydia Mackenzie ◽  
Patrick Moss ◽  
Sean Ulm
Keyword(s):  
Late Holocene ◽  
Management Practices ◽  
Fire Regime ◽  
Fire Regimes ◽  
Freshwater Wetlands ◽  
Radiometric Dating ◽  
Spatial And Temporal Variation ◽  
Pollen Record ◽  
Northern Australia ◽  
The South

This study presents three records of environmental change during the late-Holocene from wetlands across Bentinck Island in the South Wellesley Islands, northern Australia. Radiometric dating provided ages for sediment cores with the longest chronology spanning the last 1250 cal. yr BP. Palynological results show the diverse mangrove community transitioned to woodland- and wetland-dominated vegetation over the last 850 years on the southeast coast. The key driver of this landscape change was likely late-Holocene sea level regression and coastal progradation in the Gulf of Carpentaria. This study found freshwater wetlands expanded across Bentick Island over the last 500 years, with sedges and rushes peaking in the last 350 years. Macroscopic and microscopic charcoal records, coupled with archaeological evidence, highlights the spatial and temporal variation in fire regimes across the island, reflecting the traditional fire management practices of the Kaiadilt people during the late-Holocene. This study finds a significant increase in charcoal accumulation in the 1900s when Kaiadilt fire practices were disrupted and the South Wellesley Islands were abandoned. The pollen record reflects little change in the vegetation despite the shifting fire regime, highlighting the importance of multi-proxy approaches to reconstructing past environments in tropical northern Australia where vegetation is adapted to fire.

scholarly journals Reframing Wildfire Simulations for Understanding Complex Human–Landscape Interactions in Cross-Cultural Contexts: A Case Study from Northern Australia

Fire ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 46
Author(s):  
Rohan Fisher ◽  
Scott Heckbert ◽  
Stephen Garnett
Keyword(s):  
Fire Management ◽  
Cross Cultural ◽  
Mitigation Strategies ◽  
Data Sets ◽  
Northern Australia ◽  
Fire Behaviour ◽  
Fire Dynamics ◽  
Cultural Contexts ◽  
Shared Understandings ◽  
Behaviour Simulation

An increase in the frequency of severe fire events, as well as a growing interest in wildfire mitigation strategies, has created a demand for skilled managers of landscape fire and a better community understanding of fire behaviour. While on-ground experience is essential, there is potential to substantially enhance training and community engagement with explanatory simulations. Through this work, we explore landscape fire behaviour as a complex system where understanding key behaviour characteristics is often more important and achievable than prediction. It is argued that this approach has particular value in Northern Australia, where fires burn across vast and sparsely inhabited landscapes that are largely under Indigenous ownership. Land and fire management in such complex cross-cultural contexts requires combining traditional and local knowledge with science and technology to achieve the best outcomes. We describe the workings of the model, a stochastic cellular automata fire behaviour simulation, developed through a participatory modelling approach for Northern Australia; the outputs generated; and a range of operational applications. We found that simulation assisted training and engagement through the development of an understanding of fire dynamics through visualisation, underpinned by landscape data sets, and engaging a culturally diverse set of land managers in discussions of fire management. We conclude that there is scope for a broader use of explanatory fire simulations to support development of shared understandings of fire management objectives.

Fire regimes, fire-sensitive vegetation and fire management of the sandstone Arnhem Plateau, monsoonal northern Australia

2008 ◽  
Vol 35 (6) ◽  
pp. 829-846 ◽  
Author(s):  
JEREMY RUSSELL-SMITH ◽  
PAUL G. RYAN ◽  
DAVID KLESSA ◽  
GORDON WAIGHT ◽  
ROBERT HARWOOD
Keyword(s):  
Fire Management ◽  
Fire Regimes ◽  
Northern Australia

Seasonal differences in fire activity and intensity in tropical savannas of northern Australia using satellite measurements of fire radiative power

2015 ◽  
Vol 24 (2) ◽  
pp. 249 ◽  
Author(s):  
Sofia L. J. Oliveira ◽  
Stefan W. Maier ◽  
José M. C. Pereira ◽  
Jeremy Russell-Smith
Keyword(s):  
Temporal Dynamics ◽  
Fire Severity ◽  
Dry Season ◽  
Fire Season ◽  
Fire Intensity ◽  
Northern Australia ◽  
Tropical Savannas ◽  
Fire Activity ◽  
Radiative Power ◽  
Fire Radiative Power

Earth observation sensors play an important role in quantifying the energy released by fires and capturing their spatial and temporal dynamics. Using estimates of MODIS-derived fire radiative power (FRP) we characterised bushfire activity and intensity in tropical savannas of northern Australia, by season and vegetation type, over the period 2004–2012. Our results indicate that fire activity was highest in the Northern Territory and lowest in Queensland. Mean daily number of fire detections was almost twice as high in the late dry season (August–November) compared to the early dry season (May–July). Fire season was bimodal with fire activity peaks in May and October. Median fire intensity was lower for early dry season fires (29 MW) than late dry season fires (56 MW), and was positively correlated with the number of fire detections. Vegetation types with sparse canopy structure showed lower fire activity and higher intensity. Remote sensing of FRP provides frequent estimates of fire intensity over broad areas, allowing the comparison of this key fire behaviour metric across ecosystems and throughout the fire season. FRP estimates may also be used to draw inferences regarding fire effects, once the complexity and ecosystem-specificity of the relationships between fire intensity and fire severity is acknowledged.

scholarly journals A reconstruction of the recent fire regimes of Majete Wildlife Reserve, Malawi, using remote sensing

Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Willem A. Nieman ◽  
Brian W. van Wilgen ◽  
Alison J. Leslie
Keyword(s):  
Remote Sensing ◽  
Fire Management ◽  
Fire Regime ◽  
Fire Regimes ◽  
Dry Season ◽  
Annual Rainfall ◽  
Vegetation Types ◽  
Local Evidence ◽  
Hot Dry Season ◽  
Wildlife Reserve

Abstract Background Fire is an important process that shapes the structure and functioning of African savanna ecosystems, and managers of savanna protected areas use fire to achieve ecosystem goals. Developing appropriate fire management policies should be based on an understanding of the determinants, features, and effects of prevailing fire regimes, but this information is rarely available. In this study, we report on the use of remote sensing to develop a spatially explicit dataset on past fire regimes in Majete Wildlife Reserve, Malawi, between 2001 and 2019. Moderate Resolution Imaging Spectroradiometer (MODIS) images were used to evaluate the recent fire regime for two distinct vegetation types in Majete Wildlife Reserve, namely savanna and miombo. Additionally, a comparison was made between MODIS and Visible Infrared Imager Radiometer Suite (VIIRS) images by separately evaluating selected aspects of the fire regime between 2012 and 2019. Results Mean fire return intervals were four and six years for miombo and savanna vegetation, respectively, but the distribution of fire return intervals was skewed, with a large proportion of the area burning annually or biennially, and a smaller proportion experiencing much longer fire return intervals. Variation in inter-annual rainfall also resulted in longer fire return intervals during cycles of below-average rainfall. Fires were concentrated in the hot-dry season despite a management intent to restrict burning to the cool-dry season. Mean fire intensities were generally low, but many individual fires had intensities of 14 to 18 times higher than the mean, especially in the hot-dry season. The VIIRS sensors detected many fires that were overlooked by the MODIS sensors, as images were collected at a finer scale. Conclusions Remote sensing has provided a useful basis for reconstructing the recent fire regime of Majete Wildlife Reserve, and has highlighted a current mismatch between intended fire management goals and actual trends. Managers should re-evaluate fire policies based on our findings, setting clearly defined targets for the different vegetation types and introducing flexibility to accommodate natural variation in rainfall cycles. Local evidence of the links between fires and ecological outcomes will require further research to improve fire planning.

scholarly journals A late-Holocene multiproxy fire record from a tropical savanna, eastern Arnhem Land, Northern Territory, Australia

The Holocene ◽  
2021 ◽  
pp. 095968362098803
Author(s):  
Emma Rehn ◽  
Cassandra Rowe ◽  
Sean Ulm ◽  
Craig Woodward ◽  
Michael Bird
Keyword(s):  
Isotope Composition ◽  
Fire Regimes ◽  
Northern Territory ◽  
Ecosystem Dynamics ◽  
Optical Methods ◽  
Fire Intensity ◽  
Tropical Savanna ◽  
Anthropogenic Fire ◽  
Pyrogenic Carbon ◽  
Arnhem Land

Fire has a long history in Australia and is a key driver of vegetation dynamics in the tropical savanna ecosystems that cover one quarter of the country. Fire reconstructions are required to understand ecosystem dynamics over the long term but these data are lacking for the extensive savannas of northern Australia. This paper presents a multiproxy palaeofire record for Marura sinkhole in eastern Arnhem Land, Northern Territory, Australia. The record is constructed by combining optical methods (counts and morphology of macroscopic and microscopic charcoal particles) and chemical methods (quantification of abundance and stable isotope composition of pyrogenic carbon by hydrogen pyrolysis). This novel combination of measurements enables the generation of a record of relative fire intensity to investigate the interplay between natural and anthropogenic influences. The Marura palaeofire record comprises three main phases: 4600–2800 cal BP, 2800–900 cal BP and 900 cal BP to present. Highest fire incidence occurs at ~4600–4000 cal BP, coinciding with regional records of high effective precipitation, and all fire proxies decline from that time to the present. 2800–900 cal BP is characterised by variable fire intensities and aligns with archaeological evidence of occupation at nearby Blue Mud Bay. All fire proxies decline significantly after 900 cal BP. The combination of charcoal and pyrogenic carbon measures is a promising proxy for relative fire intensity in sedimentary records and a useful tool for investigating potential anthropogenic fire regimes.

Sign in / Sign up

Export Citation Format

Share Document