Traditional and contemporary fire patterns in the Great

Traditional And Contemporary Fire Patterns In The Great-Free PDF

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Executive summary, The purpose of this study was to compare and contrast the recent fire pattern in the Great Victoria. Desert GVD with that likely created by traditional pre contact Aboriginal Pila Nguru Anangu. tjuta pila nguru burning We used a chronosequence of Landsat satellite imagery from 2000 2016 to. reconstruct and quantify the contemporary pattern over an area of 12 879 615 ha and the earliest. black and white aerial photography taken in 1960 61 to reconstruct and quantify Anangu burning. patterns Depopulation and displacement of Anangu began in the GVD as early as the late 1940s so by. the time of the aerial photography there were relatively few groups extant Based on best available. knowledge we acquired aerial photography over those areas where people were most likely to be. covering an area of 1 049 222 ha To better understand how and why the GVD Anangu people used. fire we reviewed the limited literature and via video link with the TjunTjunjara community. participated in discussions about fire with elders. As with most other spinifex dominated Australian deserts the contemporary fire pattern in the GVD. is characterised by cycles of very large areas burnt by hot fires in spring summer followed by. periods of lower fire activity a cycle largely driven by rainfall Over the 17 year study period the. mean and maximum fire sizes were 3 699 ha and 1 033 121 ha respectively This contrasted strongly. with the size of fires mostly attributed to Anangu burning visible on the 1960 61 aerial photgraphy. While the photography is literally a snapshot in time and space the mean and maximum fire sizes. were 11 2 ha and 3 953 ha respectively The fire scars on the photographs were clustered probably. reflecting the locations of small groups of people Compared with similar studies in the Great Sandy. Gibson Deserts the extent of recent burning evident on the old aerial photographs was limited with. only about 2 7 of the study area showing visible signs of having been recently burnt This probably. reflects the sparse population at the time of photography and relatively large areas of low. flammability vegetation in this region of the GVD, Fire played and continues to play an important role in the spritual and physical well being of people. It is clear from the old aerial photographs that the people who carried out the burning had a sound. knowledge of fire behvaiour they were able to keep the fires small because they understood. relationships between fire behaviour vegetation fuel and weather especially wind There were good. reasons why fires were kept small large fires were unnecessary wasteful and of little benefit to. Anangu Reasons for burning were many and varied and consistent with other Western Desert people. the predominant reason for burning was food acquisition A beneficial consequence of broadscale. patch burning was that it mitigated or buffered the harmful effects of hot season bushfires. While there is some level of fire management in the GVD most of the region experiences. unmanaged fire patterns dominated by large hot bushfires which are harmful to biodiversity are. environmentally degrading and are contributing to greenhouse gas emissions Action is needed to. increase the capacity of people to better manage fire in the GVD and to re instate traditional Anangu. fire management across larger areas of high cultural and conservation value Traditional fire. management carried out at appropriate scales as well as other benefits can reduce greenhouse gas. emissions and increase carbon sequestration The future carbon market could provide opportunities. for self funding fire management delivering social cultural economic environmental and. conservation benefits,1 Introduction, Spinifex grasslands are characterised by the dominance of perennial hummock grasses primarily of. the genus Triodia They occur on a diversity of landforms and soils including sand plains dune fields. stony plains and rocky hills in the semi arid and arid regions of the remote and sparsely populated. central and northern parts of Australia Spinifex grasslands cover about 2 1 million km2 27 of the. continent of which about 800 000 km2 40 is on Aboriginal land Allan and Southgate 2002 The. climate is arid or semi arid with annual average rainfall ranging from about 225 mm to 350 mm In. the north rainfall is predominantly in the summer while in the south it is somewhat non seasonal. remnants of tropical cyclones and thunderstorms associated with troughs can result in summer rainfall. and the passage of cold fronts can result in winter rainfall Typical of desert climates rainfall is highly. variable and long periods of drought are not uncommon The summers are long and hot and winters. cool and mild Spinifex grasslands are generally structurally simple with a discontinuous ground. cover of Trioda spp spinifex hummocks to a height of 25 50 cm Scattered low shrubs mallees and. trees usually grow in association with spinifex Burrows et al 1991 Beard et al 2013 Notable. shrub tree and mallee form genera sometimes associated with spinifex include Eucalyptus Corymbia. Allocasuarina Acacia Callitris Hakea and Grevillea. The combination of accumulations of flammable vegetation the physical structure of the hummocks. and the often extreme fire weather conditions makes spinifex grasslands highly flammable Griffin. and Allan 1984 Burrows et al 1991 Allan and Southgate 2002 Historically lightning and. deliberate burning by Aboriginal people were the main causes of fire Today most fires are started by. lightning although human caused ignitions are significant near settlements along vehicle travel. routes and in association with land management practices on Aboriginal and conservation lands. While most Triodia species are fire sensitive readily killed by fire spinifex grassland communities. are fire maintained fires at appropriate temporal and spatial scales are essential for their persistence. and health Burbidge 1944 Suijdendorp 1981 Griffin and Friedel 1984. Under traditional law and custom Aboriginal people inherit exercise and bequeath customary. responsibilities to manage their traditional country The relatively recent displacement of Aboriginal. people from parts of central Australia Cane 2002 Davenport et al 2005 has coincided with an. alarming decline in some native mammal and bird species and a contraction of some fire sensitive. plant communities Proposed causes of these changes include an altered fire regime resulting from the. departure of traditional Aboriginal burning practices predation by introduced carnivores and. competition with feral herbivores Johnson 1988 Burbidge and McKenzie 1989 Morton 1990 Latz. 1995 Gammage 2011 While knowledge of fire effects in hummock grasslands is incomplete there. is strong evidence of dramatically changed fire regimes in parts of the Gibson and Great Sandy. Deserts since the displacement of Aboriginal people and the associated decline of traditional burning. In general there has been a reduction in diversity of fire regimes frequency season intensity and. scale and an increase in the intensity and scale of hot spring and summer bushfires This has resulted. in a shift from a pyrogenic fine grained habitat mosaic to pyrogenic homogenization Burrows and. Christensen 1990 Allan and Southgate 2002 Bliege Bird et al 2005 Burrows et al 2006 over much. of the spinifex grasslands,1 1 Evidence of altered fire regimes. While there is considerable anecdotal evidence of changed fire regime following the departure of. traditional Aboriginal burning in much of the spinifex grasslands e g Bolton and Latz 1978 Latz. and Griffin 1978 Latz 1995 Bowman et al 1995 the most compelling and quantifiable evidence. comes from a study linking oral evidence from Traditional Owners with relatively high resolution. good quality black and white aerial photography taken by the Australian British military over a. remote area of the Great Sandy and Gibson Deserts west and south of Lake McKay in 1953 At the. time of photography Aboriginal people were living a traditional lifestyle more than a decade before. European contact Davenport et al 2005 Burrows and Christensen 1990 and Burrows et al 2006. studied a sample of the aerial photography covering about 2 500 km2 and it revealed a mosaic of. numerous small burnt patches The mean burnt patch size was about 60 ha with most 75 of the. burnt patches being less than 32 ha and 50 less than 5 ha Burrows et al 2006 About 20 of the. area was burnt by fires 100 ha and 36 by fires 1 000 ha the largest fire being about 6 000 ha. Burrows et al concluded that based on fire shape and on information provided by Martu and Pintupi. people most of the burnt patches were consistent with having been lit by people who burnt the. spinifex for a myriad of reasons but primarily for acquiring food Aerial photography is a snapshot of. a place at a time so caution is needed when extrapolating the fire patterns seen on the 1953 photos to. other times and places However the early photographic evidence was entirely consistent with oral. descriptions of traditional fire use Burrows et al 2006. Plate 1 Early 1953 pre contact aerial photography over the Great Sandy Desert clearly revealing fine scale. Pintupi burning patterns light areas, The fire patterns resulting from a fire regime dominated by Aboriginal burning contrasts sharply with.
the more recent fire regime following the displacement of people and or the cessation of traditional. burning from much of these lands By the mid 1970s some 15 20 years after the decline of traditional. burning the fire regime in the Great Sandy and Gibson Deserts had changed Satellite imagery. revealed that the mosaic of small low intensity cool fires evident on the 1953 photography had been. replaced by large intense hot bushfires primarily ignited by lightning the average fire size today is. many orders of magnitude greater than the fires set under Aboriginal management. As with the reported case study Burrows et al 2006 the fire regime in most of spinifex dominated. central Australia has changed from a stable pattern of numerous small cool fires to an unstable. pattern of large hot summer bushfires followed by intervening periods of few fires because of lack of. vegetation to burn culminating in large hot bushfires once the fuel has re accumulated For example. over the period 2000 2002 500 000 km2 of spinifex grassland was burnt Wright and Clarke 2007. and hot summer bushfires commonly exceed 200 000 ha Haydon et al 2000 Allan and Southgate. 2003 Burrows et al 2009 This boom and bust fire regime is now largely driven by rainfall which. drives the rate of fuel accumulation Griffin 1992 Allan and Southgate 2002 Murphy and Barr. 2014 with lightning as the dominant ignition source whereas for thousands of years burning by. people was a significant influence on the fire regime over much of the region. While there has been work done on quantifying and documenting historical and contemporary fire. patterns in the northern deserts Gibson Great and Little Sandy Deserts little has been done in the. Great Victoria Desert region of Western Australia Therefore the overarching objective of this project. is to better understand traditional Aboriginal Anangu burning patterns in the spinifex grasslands of. the Great Victoria Desert GVD specifically the Spinifex Native Title Determination Area Spinifex. Lands as a basis for informing contemporary fire management The study attempts to reconstruct. traditional burning patterns from the earliest aerial photography taken at a time when some Anangu. were known to be living a traditional lifestyle The value of the aerial photography for. understanding traditional burning practices depends on its timing in relation to the timing of the initial. departure of Anangu and their burning practices from these lands Using aerial photogrpahy to. understand and quantify fire patterns was complemented by reviewing the literature and having some. conversations with Anangu elders about traditional use of fire. This project also aimed to compare and contrast traditional Anangu induced fire patterns with the. contemporary lightning induced fire patterns 2000 2016 reconstructed using Landsat satellite. imagery Knowledge of traditional fire patterns in the spinifex grasslands of the GVD as well as. being of cultural significance can also inform contemporary fire management for ecosystem health. and biodiversity outcomes,2 1 Study site and target areas. The GVD its location approximated by the GVD Interim Bioregionalisation of Australia IBRA. Figure 1 is characterised by sandplains and east west trending dunefields Vegetation cover is. predominantly spinifex Triodia spp often with an overstorey of scattered trees such as marble gum. Eucalyptus gonglyocarpa mulga wanari Acacia aneura yarltarrpa E youngiana and. Kingsmill s mallee E kingsmillii Land tenure of most of the region is unallocated crown land. conservation reserves and Aboriginal land The climate is arid with variable and unreliable rainfall. Spatially averaged median rainfall is 162 mm and the study area lies between the 150 mm and 200. mm mean annual rainfall isohyets making it one of Australia s driest regions BoM By comparison. the mean rainfall for Warburton and Giles in the Gibson Desert to the north is significantly higher at. 259 mm and 292 mm respectively, Following along the lines of earlier work in the Gibson Desert Burrows and Christensen 1990. Burrows et al 2006 the original intention was to acquire 1953 aerial photography the earliest. spinifex for a myriad of reasons but primarily for acquiring food Aerial photography is a snapshot of a place at a time so caution is needed when extrapolating the fire patterns seen on the 1953 photos to other times and places However the early photographic evidence was entirely consistent with oral

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