Anangu Pitjantjatjara Lands Biological Survey RESULTS VEGETATION By P. J. Lang1, P. D. Canty1, B. J. Nesbitt2, L. M. Baker2 and A. C. Robinson1 INTRODUCTION Vegetation overview This chapter gives an introductory overview of The biogeography of the AP Lands is complex. The vegetation in the Anangu Pitjantjatjara Lands (AP range of landforms, soils and rock types, and Lands) and a brief review of previous botanical microclimates combine to provide the most diverse endeavour. This is followed by sections detailing expression of arid landscapes in South Australia. The various aspects of the flora, including new records and area, by virtue of its remoteness and lack of obvious accounts of species of particular significance. The next resources, has also remained relatively pristine, further section presents data collected by Baker and Nesbitt enhancing the biological importance of this region. integrating much of the Anangu traditional ecological The AP Lands include the tallest mountains in the knowledge provided during the survey. An analysis of State. The largest range complex, the Musgrave the quadrat-based vegetation data follows and the Ranges, has the highest mean annual rainfall (200 mm) resultant vegetation groups are described. in the Northern Arid Province (Laut et al. 1977). Altitude, aspect and drainage patterns associated with Only ‘public’ information was recorded from Anangu. these and other range systems in the region have a Prior to any survey information being collected, significant influence on vegetation, harbouring unique discussions were held with the Anangu survey plant communities, relict species and endemics. participants, to clarify what type of information was Depositional landforms surround the ranges and being sought and how it would be made available to the include extant and palaeo drainage systems. general public. Anangu then determined what type of information it would be appropriate for them to Vegetation communities are dominated by typical arid- provide. This was critical as the information collected adapted species with understorey vegetation largely of was intended for presentation in reports, papers, and spinifex hummock grasses (Triodia species) and short- other print media. Collection of non-public, culturally lived tussock grasses and herbs. Richer, more complex select information would expose readers to knowledge soils and higher rainfall support a particularly diverse that would contravene traditional Law. range of woodland species. This is in contrast to the adjacent desert regions where Mulga and mallee are The information collected was compiled as an predominant. The AP Lands support a wide variety of ACCESS database with scientific plant names linked to characteristic central Australian tree species, including the SA FLORA system. This database is held by the Desert Oak (Allocasuarina decaisneana), Hill Anangu Pitjantjatjara. Information provided on species Bloodwood (Corymbia eremaea), Native Rock Fig by different Anangu informants is cross-referenced (Ficus brachypoda), White Cypress Pine (Callitris which enables different language names for species to glaucophylla), Corkwoods (Hakea lorea and H. be retrieved and validated. The ACCESS database divaricata), Ironwood (Acacia estrophiolata), Desert and all information recorded from Anangu is the Kurrajong (Brachychiton gregorii) and Marble Gum property of Anangu Pitjantjatjara. (Eucalyptus gongylocarpa). The presentation of information in this report The southern section of the AP Lands encompasses the summarises the Anangu contribution to the northern extent of the sand plains and dune fields of the knowledge of the flora and fauna of the AP Lands Great Victoria Desert, the biologically richest and most for the survey. It is not provided for others to use pristine sandy desert in the State. Unlike other major for profit by exploitation of Anangu traditional South Australian deserts, the Great Victoria Desert knowledge with regard their use of plants or supports a surprisingly dense and diverse cover of animals as food or for medicinal purposes. This vegetation with mallee eucalypts particularly well data is the property of Anangu Pitjantjatjara and represented in both species richness and abundance. In cannot be used for any purpose without the written the east, gently undulating plains and drainage systems permission of Anangu Pitjantjatjara. feed into the Lake Eyre Basin and include gibber 1 (stony) plains and dissected tablelands (breakaway ranges) characterised by chenopod shrublands (Atriplex, Maireana and Sclerolaena species), thick 1 SA Department for Environment and Heritage, PO Box1047, ADELAIDE, SA 5001 2 Wallambia Consultants. 1070 South Arm Rd. URUNGA, NSW 2455 65 Mulga (Acacia aneura complex) woodlands and are replaced by a second vegetation type dominated by ephemeral fresh-water swamps. T. irritans. In the third major upland vegetation type, spinifex cover is absent or very limited. Instead the The region generally appears to be in a relatively ground layer is dominated by a diverse range of natural condition, with many areas infiltrated by no perennial tussock grasses and herbs and there are better more than a few introduced weed species and lacking developed shrub and tree layers characterised by fire- other obvious forms of disturbance. The sand-plain sensitive White Cypress Pine (Bowman and Latz 1993) and dune communities are particularly undisturbed. and Mulga. Since European settlement though, changes to traditional Aboriginal burning practices, grazing by By virtue of its remoteness and lack of reliable water, feral animals such as rabbits, camels and donkeys, and the region’s vegetation escaped the intense changes relatively localised impacts from pastoralism, have all normally associated with European settlement. The been influencing the status and distribution of both continued presence of Aboriginal people prolonged individual plant species and communities. Although traditional land management practices as compared to early explorer accounts of the region are generally not other areas of the State, probably until severe droughts detailed enough to gauge specific changes since early in the 19th century forced most Aboriginal European settlement, the extinction of many medium- families to seek refuge in the newly opened Christian sized native mammal species from this and similar missions. regions in central Australia, and anecdotal evidence, suggests that significant changes to vegetation have Up until this time, such traditional practices as patch occurred. burning would have had a significant influence on vegetation in all but the regions most remote from any The interruption of traditional burning practices has reliable water source (Morelli 1992, Latz 1996). generated more uniform vegetation patterns with a Burning was carried out for a variety of reasons, for tendency towards lower diversity of many plant example: species, less variation in age structure, senescence, and, • to enhance the growth and availability of palatable with higher and more uniform litter loads, a greater species (fire in mature spinifex areas combined susceptibility to hot and widespread wildfires. The with rainfall events increases species diversity, and impact of feral animals is more evident in, and in the more importantly an increase in edible plants vicinity of, the range systems. The generally richer and including Solanum spp, Eragrostis spp., Panicum more reliably watered soils, particularly in the range decompositum var decompositum, and Calandrinia outwash zones, and prolonged presence of water in spp.); waterholes during dry times, has resulted in over • to encourage the presence of hunted animals such grazing in these areas. This in turn has promoted as Red Kangaroos and Euros; dominance of unpalatable and/or short-lived (often • to protect fire sensitive and culturally valuable introduced) weedy species. Where hot wildfires have species such as the Rock Fig and Mulga from infiltrated previously protected areas such as Mulga wildfire by seasonal burning-off in surrounding woodlands, regeneration of the community has been vegetation. prevented or greatly reduced by the impact of feral animal grazing and browsing and probably, in some The nature of this type of burning resulted in the cases, by repeated hot fires. landscape having a mosaic of vegetation in different stages of post-fire regeneration. The effect of this type The ranges are notable in many areas for their lack of of fire regime, most likely carried out for tens of tree and shrub cover, supporting instead a relatively thousands of years, would have encouraged a high uniform cover of spinifex (Triodia species). The diversity of plant and animal species able to cope with ranges, though, host considerable diversity in tree and fire, but possibly had a negative impact on species less shrub species including fire-sensitive species such as tolerant of fire. The deliberate protection of fire- White Cypress Pine (Callitris glaucophylla) and Rock sensitive but culturally valuable species to assist their Fig (Ficus brachypoda) – as the majority of the survival supports this possibility. relictual and endemic species occur in the ranges. Tree species are often only represented by mature or The range vegetation in the AP Lands in particular, senescent examples. Regeneration is restricted and hints at the impact of fire. This would appear to be a patchy (though often vigorous) and appears less in result of wildfire, as Anangu did not deliberately burn spinifex-dominated
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