The short-term effects of an extensive and high-intensity fire on vertebrates in the tropical savannas of the central Kimberley, northern Australia

2008 ◽  
Vol 35 (1) ◽  
pp. 33 ◽  
Author(s):  
Sarah Legge ◽  
Stephen Murphy ◽  
Joanne Heathcote ◽  
Emma Flaxman ◽  
John Augusteyn ◽  
...  
Keyword(s):  
Species Richness ◽  
High Intensity ◽  
Fire Frequency ◽  
Northern Australia ◽  
Tropical Savannas ◽  
Short Term ◽  
Large Herbivores ◽  
Species Richness And Abundance ◽  
Species Specific ◽  
In Fire

We report the effects of an extensive (>7000 km2), high-intensity late-dry-season fire in the central Kimberley, Western Australia, on the species richness and abundance of mammals, reptiles and birds. Five weeks after the fire we surveyed 12 sites (six burnt, six unburnt); each pair of sites was closely matched for soil type and vegetation. The species richness and abundance of mammals and reptiles was greater at unburnt sites, especially for mammals (with a 4-fold difference in abundance between burnt and unburnt sites). There was an indication that reptiles immigrated into unburnt patches, but mammals did not. There were also species-specific responses to the fire: Rattus tunneyi and Pseudomys nanus were much more abundant in unburnt sites, whereas Pseudomys delicatulus was caught in equal numbers at burnt and unburnt sites. Diurnal reptiles were more abundant at unburnt sites, but nocturnal reptiles were equally common at burnt and unburnt sites. Avian species richness and overall abundance was similar between burnt and unburnt patches, although a few species showed preferences for one state or the other. The overall high trapping success for mammals (18% across all sites; 28% in unburnt patches) contrasts with the well documented mammal collapse in parts of northern Australia and seems paradoxical given that our study area has experienced the same increase in fire frequency and extent that is often blamed for species collapse. However, our study area has fewer pressures from other sources, including grazing by large herbivores, suggesting that the effects of these pressures, and their interaction with fire, may have been underestimated in previous studies.

Fire experiments in northern Australia: contributions to ecological understanding and biodiversity conservation in tropical savannas

2003 ◽  
Vol 12 (4) ◽  
pp. 391 ◽  
Author(s):  
R. J. Williams ◽  
J. C. Z. Woinarski ◽  
A. N. Andersen
Keyword(s):  
Field Experiments ◽  
Fire Regime ◽  
Spatial And Temporal Variability ◽  
Northern Australia ◽  
Natural Experiments ◽  
Tropical Savannas ◽  
Ecological Understanding ◽  
Manipulative Experiments ◽  
In Fire ◽  
Fire Experiments

The management of fire in savannas has been informed by a strong tradition of fire experiments, especially in Africa. This research tradition is much shorter in the 2 million square kilometres of tropical savannas in northern Australia, but has yielded several natural experiments, and three designed, manipulative, controlled field experiments (hereafter 'manipulative' experiments) of international significance (at Munmarlary, Kapalga and Kidman Springs in the Northern Territory). Here we assess the contributions of experiments, in particular the manipulative experiments, to ecological understanding and biodiversity management in Australia's savannas. Running from 1973 to 1996, the Munmarlary experiment comprised hectare-scale experimental plots with four replicated dry season fire treatments, and was designed to examine interactions between fire, landscape and biodiversity. The Kapalga experiment ran from 1989 to 1995, with a range of fire treatments broadly similar to those at Munmarlary. However, experimental units were 10–20�km2 sub-catchments, making it one of the largest, replicated fire experiments ever conducted. The Kidman Springs experiment focused on grass-layer productivity and composition to meet the needs of the pastoral industry, but also provided an opportunity to examine biodiversity responses to different fire regimes. Methodologically, the experiments have generally focused on phenomena—the responses to different fire treatments of individual taxa—rather than on mechanisms that determine response syndromes. They have highlighted that a range of responses to differences in fire regime is possible, and that no single fire regime can optimise all biodiversity outcomes. For effective conservation of biodiversity in the face of such complexity, conservation goals will need to be made explicit. The existing portfolio of manipulative experiments is incomplete, lacking especially a consideration of some critical savanna taxa and environments, and providing little information on the significance of spatial and temporal variability in fire patterns, especially at small scales. An understanding of fire in Australian savanna landscapes remains inadequate, so there is a continuing need for close partnerships between scientists and conservation managers, with fire management treated as a series of landscape experiments in an adaptive management framework.

An analysis of fire frequency in tropical savannas of northern Australia, using a satellite-based fire atlas

2013 ◽  
Vol 22 (4) ◽  
pp. 479 ◽  
Author(s):  
Sofia L. J. Oliveira ◽  
M. A. Amaral Turkman ◽  
José M. C. Pereira
Keyword(s):  
Vegetation Type ◽  
Weibull Model ◽  
Fire Frequency ◽  
Northern Australia ◽  
Tropical Savannas ◽  
Probability Models ◽  
Burnt Area ◽  
Hazard Functions ◽  
Early Peak ◽  
Fire Intervals

We characterised fire frequency in western Arnhem Land, northern Australia (~24 000 km2), during the period 1990–2008, using available satellite burnt area maps. We estimated fire mortality and fire survival distributions, and hazard functions by vegetation type. We tested the performance of three probability models to study fire interval distributions: continuous and discrete Weibull, and discrete lognormal. Over the 19 year study period the mean annual area burnt was 36%. Median fire intervals ranged from 1 to 4 years. The discrete lognormal model best fitted the data, yielding non-monotonic hazard functions that peak at 2 to 3 years, making it more appropriate for fire frequency analysis in fire-prone tropical savannas than the more popular Weibull model. Open forest showed the highest flammability dependence on fuel age, and closed forest the lowest. The probability of burning as a function of time since last fire reaches an early peak and subsequently declines, due to fuel dynamics in these flammable savanna systems. Age-specific fire incidence is much higher for older vegetation patches than was suggested by earlier analysis of fire interval distributions. Fitting an appropriate model is important to characterize the observed fire frequency patterns, and make inferences for unobserved, longer fire intervals.

Response of a shrubland mammal and reptile community to a history of landscape-scale wildfire

2015 ◽  
Vol 24 (4) ◽  
pp. 534 ◽  
Author(s):  
Tim S. Doherty ◽  
Robert A. Davis ◽  
Eddie J. B. van Etten ◽  
Neil Collier ◽  
Josef Krawiec
Keyword(s):  
Fire History ◽  
Fire Management ◽  
Local Level ◽  
Fire Frequency ◽  
Specific Information ◽  
Fire Exclusion ◽  
Management Approaches ◽  
Species Specific ◽  
Taxonomic Groups ◽  
In Fire

Fire plays a strong role in structuring fauna communities and the habitat available to them in fire-prone regions. Human-mediated increases in fire frequency and intensity threaten many animal species and understanding how these species respond to fire history and its associated effect on vegetation is essential to effective biodiversity management. We used a shrubland mammal and reptile community in semiarid south-western Australia as a model to investigate interactions between fire history, habitat structure and fauna habitat use. Of the 15 species analysed, five were most abundant in recently burnt habitat (8–13 years since last fire), four were most abundant in long unburnt areas (25–50 years) and six showed no response to fire history. Fauna responses to fire history were divergent both within and across taxonomic groups. Fire management that homogenises large areas of habitat through either fire exclusion or frequent burning may threaten species due to these diverse requirements, so careful management of fire may be needed to maximise habitat suitability across the landscape. When establishing fire management plans, we recommend that land managers exercise caution in adopting species-specific information from different locations and broad vegetation types. Information on animal responses to fire is best gained through experimental and adaptive management approaches at the local level.

scholarly journals Effects of fire frequency on savanna butterfly diversity and composition: A preliminary study

Koedoe ◽  
2020 ◽  
Vol 62 (1) ◽  
Author(s):  
Elie Gaget ◽  
Catherine L. Parr ◽  
Clélia Sirami
Keyword(s):  
Species Richness ◽  
Low Frequency ◽  
Fire Regimes ◽  
Spatial Diversity ◽  
Fire Frequency ◽  
Management Tool ◽  
Butterfly Diversity ◽  
Fire Experiment ◽  
In Fire

Fire plays a major role in many biomes, is widely used as a management tool and is likely to be affected by climate change. For effective conservation management, it is essential to understand how fire regimes affect different taxa, yet responses of invertebrates are particularly poorly documented. We tested how different fire frequencies influence savanna butterfly diversity and composition by using a long-term savanna fire experiment initiated in 1954 in the Kruger National Park (South Africa). We compared butterfly abundance, species richness and community composition across three fire frequencies: high (burnt annually), medium (burnt triennially) and low (burnt twice in 60 years). Plots with high fire frequency hosted higher abundance than medium- or low-frequency plots. Fire frequencies did not affect species richness, but they led to distinct communities of butterflies. Our findings suggest that, in view of the three fire frequencies tested, a spatial diversity of fire frequencies may increase butterfly diversity at the landscape level in wet savannas. Managers may need to promote a greater diversity of fire frequencies by increasing fire frequency in some areas to provide habitat for species requiring high fire frequency, and by decreasing fire frequency in a large proportion of the landscape to provide fire refuges. This study provides new insights for butterfly conservation in savannas and highlights several knowledge gaps, which further studies should address for insect responses to be given adequate consideration in fire management strategies.Conservation implications: A spatial diversity of fire frequencies may increase butterfly diversity. Managers may need to promote a greater diversity of fire frequencies by increasing fire frequency in some areas to provide habitat for species requiring high fire frequency, and by decreasing fire frequency in other areas to provide fire refuges.

scholarly journals Overlapping den tree selection by three declining arboreal mammal species in an Australian tropical savanna

2020 ◽  
Vol 101 (4) ◽  
pp. 1165-1176
Author(s):  
Cara E Penton ◽  
Leigh-Ann Woolley ◽  
Ian J Radford ◽  
Brett P Murphy
Keyword(s):  
High Intensity ◽  
Individual Species ◽  
Rapid Decline ◽  
Northern Australia ◽  
Tropical Savannas ◽  
Mammal Species ◽  
Tree Cavities ◽  
Large Trees ◽  
Tree Cavity ◽  
Arboreal Mammal

Abstract Tree cavities are important denning sites for many arboreal mammals. Knowledge of cavity requirements of individual species, as well as potential den overlap among species, is integral to their conservation. In Australia’s tropical savannas, development of tree cavities is enhanced by high termite activity, and, conversely, reduced by frequent fires. However, it is poorly understood how the availability of tree cavities in the tropical savannas impacts tree cavity use and selection by cavity-dependent fauna. There has been a severe decline among arboreal mammal species in northern Australia over recent decades. Investigation of their cavity requirements may illuminate why these species have declined drastically in some areas but are persisting in others. Here we examined this issue in three species of arboreal mammals (Trichosurus vulpecula, Mesembriomys gouldii, Conilurus penicillatus) on Melville Island, northern Australia. We radiotracked individuals to their den sites to evaluate whether the species differ in their den tree and tree-cavity selection. The strongest influence on den tree selection was the presence of large cavities (> 10 cm entrance diameter), with all three species using larger cavities most frequently. Conilurus penicillatus, the smallest species, differed the most from the other species: it frequently was found in smaller, dead trees and its den sites were closer to the ground, including in hollow logs. The two larger species had broader den tree use, using larger live trees and dens higher up in the canopy. Dens of C. penicillatus are likely to be more susceptible to predation and destruction by high-intensity savanna fires. This may have contributed to this species’ rapid decline, both on Melville Island and on the mainland. However, the apparent preference for larger tree cavities by all three arboreal species is concerning due to the limited availability of large trees across Australian savannas, which are subject to frequent, high-intensity fires.

Correlates of grass-species composition in a savanna woodland in northern Australia

2009 ◽  
Vol 57 (1) ◽  
pp. 10 ◽  
Author(s):  
K. A. Scott ◽  
S. A. Setterfield ◽  
A. N. Andersen ◽  
M. M. Douglas
Keyword(s):  
Species Composition ◽  
Vegetation Structure ◽  
Spatial Scales ◽  
Fire Frequency ◽  
Grass Species ◽  
Northern Australia ◽  
Tropical Savannas ◽  
Environmental Characteristics ◽  
Savanna Woodland ◽  
Litter Cover

Environmental features associated with the distribution of grass species are poorly known in tropical savannas, particularly at smaller spatial scales. The present study aimed to determine the relative influence of 11 environmental characteristics on grass-species composition in a savanna woodland in northern Australia. Environmental characteristics relating to woody-vegetation structure and soil, plus the long-term (14-year) fire frequency, were documented along an environmental gradient and compared with grass-species composition. Differences in grass-species composition, as well as richness and evenness, were related to differences in vegetation structure and edaphic characteristics. In particular, grass-species composition was most strongly related to plant-available moisture, the density of woody plants in the midstorey (2.0–9.99 m height), and canopy and litter cover. Grass-species richness and evenness were extremely low in areas where midstorey density, canopy cover and litter cover were high, and where soil moisture content in the root zone of grasses was low. Differences in fire frequency also influenced grass-species composition, with areas that had experienced lower fire frequency during the previous 14 years having lower density of the annual grass Sorghum intrans (F.Muell. ex Benth.) and the perennial grass Heteropogon triticeus (R.Br.) Stapf, and increased dominance of the perennial Eriachne triseta Nees ex Steud. The results of the present study demonstrate a complex interplay between bottom-up environmental factors and top-down processes such as fire, as determinants of grass-species composition in tropical savannas.

Fire severity in a northern Australian savanna landscape: the importance of time since previous fire

2010 ◽  
Vol 19 (1) ◽  
pp. 46 ◽  
Author(s):  
Brett P. Murphy ◽  
Jeremy Russell-Smith
Keyword(s):  
Fire History ◽  
Fire Severity ◽  
Severity Index ◽  
Fire Frequency ◽  
Dry Season ◽  
Strong Increase ◽  
Northern Australia ◽  
Feedback Process ◽  
Clear Trend ◽  
In Fire

Using a detailed fire history collected over a 10-year period throughout a savanna landscape in northern Australia, we have addressed the question of whether fire severity, inferred from a semiquantitative fire severity index, increases with time since previous fire. There was a clear trend of fires becoming much more severe with increasing time since previous fire. Between 1 and 5 years following a fire, the probability of a subsequent fire being classified as ‘severe’ increased from 3 to 8% for early dry-season fires, and from 21 to 43% for late dry-season fires. It was clear that the strong increase in fire severity was not confined to the first 2–3 years following the previous fire, as previously suspected. These findings highlight the difficulty of reducing both fire frequency and severity in northern Australian savanna landscapes, as they imply that a negative feedback process exists between the two; that is, reducing fire frequency is likely to increase the severity of fires that do occur.

Does fire limit tree biomass in Australian savannas?

2015 ◽  
Vol 24 (1) ◽  
pp. 1 ◽  
Author(s):  
Brett P. Murphy ◽  
Adam C. Liedloff ◽  
Garry D. Cook
Keyword(s):  
Conceptual Model ◽  
Upper Bound ◽  
Water Availability ◽  
Fire Management ◽  
Fire Frequency ◽  
Tropical Savannas ◽  
Tree Biomass ◽  
Tree Layer ◽  
Recruitment Bottleneck ◽  
In Fire

Processes allowing coexistence of trees and grasses in tropical savannas have long intrigued ecologists. Early theories focused on climatic controls, but a conceptual model has emerged suggesting that savanna trees are subject to a fire-mediated recruitment bottleneck, with frequent fires preventing recruitment of saplings into the tree layer and maintaining biomass well below its climate-determined upper bound. We propose that this conceptual model has been overemphasised in northern Australia, where tree abundance is more strongly controlled by water availability. The dominant trees, eucalypts, have a remarkable capacity to grow through the ‘fire trap’ to reach fire-resistant sizes. This fire tolerance makes eucalypts relatively unresponsive to management-imposed reductions in fire frequency and intensity. Other trees in these savannas are typically more fire sensitive and respond positively to such management. There are suggestions that savanna fire management could lead to increases in woody biomass, but we contend that if tree biomass is strongly limited by water availability, then potential increases in tree biomass are relatively limited, at least in relation to the dominant eucalypt component. There is potential to increase the biomass of the more fire-sensitive non-eucalypts, but the upper bound of non-eucalypt tree biomass in these eucalypt-dominated systems remains poorly understood.

Conservation value of low fire frequency in tropical savannas: Ants in monsoonal northern Australia

2010 ◽  
Vol 36 (5) ◽  
pp. 497-503 ◽  
Author(s):  
ALAN N. ANDERSEN ◽  
BENJAMIN D. HOFFMANN
Keyword(s):  
Fire Frequency ◽  
Conservation Value ◽  
Northern Australia ◽  
Tropical Savannas

scholarly journals Non pharmacological high-intensity ultrasound treatment of human dermal fibroblasts to accelerate wound healing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jeong Yu Lee ◽  
Dae-Jin Min ◽  
Wanil Kim ◽  
Bum-Ho Bin ◽  
Kyuhan Kim ◽  
...  
Keyword(s):  
Wound Healing ◽  
High Intensity ◽  
Mapk Pathway ◽  
Dermal Fibroblasts ◽  
Ultrasound Treatment ◽  
Type I ◽  
Human Dermal Fibroblasts ◽  
Short Term ◽  
High Intensity Ultrasound ◽  
Extracellular Matrix Components

AbstractInspired by the effectiveness of low-intensity ultrasound on tissue regeneration, we investigated the potential effect of short-term high-intensity ultrasound treatment for acceleration of wound healing in an in vitro wound model and dermal equivalent, both comprising human dermal fibroblasts. Short-term ultrasound of various amplitudes significantly increased the proliferation and migration of fibroblasts and subsequently increased the production of the extracellular matrix components fibronectin and collagen type I, both of which are important for wound healing and are secreted by fibroblasts. In addition, ultrasound treatment increased the contraction of a fibroblast-embedded three-dimensional collagen matrix, and the effect was synergistically increased in the presence of TGF-β. RNA-sequencing and bioinformatics analyses revealed changes in gene expression and p38 and ERK1/2 MAPK pathway activation in the ultrasound-stimulated fibroblasts. Our findings suggest that ultrasound as a mechanical stimulus can activate human dermal fibroblasts. Therefore, the activation of fibroblasts using ultrasound may improve the healing of various types of wounds and increase skin regeneration.

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