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ISSN 0083-8675 Department of Agriculture Agdex 320/10 Western Australia ljt@©Duuuoccg([lO D ~lliJ @ DOl An inventory and condition survey of the nort~ . -e . ~stern Goldfields, Western Australia H.J.R. Pringle AM.E.VanVreeswyk SA Gilligen An inventory and condition survey of rangelands in the north-eastern Goldfields, Western Australia Compiled by: H.J.R. Pringle, A.M.E. Van Vreeswyk and S.A. Gilligan Editor: K.M.W. Howes Technkal Bulletin 1\:0. 87 December 1994 Department of Agriculture Baron-Hay Court SOUTH PERTI-I 6151 Western Australia rSSN 0083-8675 i 16631-1 The compilers HJ.R. Pringle and A.M.E. Van Vreeswyk, Division of Regional Operations, Natural Resources Assessment Group, Department of Agriculture, Western Australia, and S.A. Gilligan, Geodetic Services, Department of Land Administration, Western Australia. Other contributors E. Faithful!, previously with Department of Agriculture Western Australia, A.D. Allen, Geological Survey, Department of Mineral, and Energy Western Australia, A.J. Stevens, Agriculture Protection Board, Western Australia. Definition The north-eastern Goldfields, as featured in this report, includes the areas covered by the following 1:250,000 map sheets: Sir Samuel, Duketon, Leonora, Laverton, Menzies and Edjudlna; plus additional small areas representing minor portions of pastoral leases falling outside of the boundaries of the map sheet,. TIle north-eastern Goldfields contains multiple biogeographic, physiographic and administrative boundaries and as such does not warrant recognition as a region in its own right. The National Library of Australia cataloguing in Publication entry Pringle, H. J. An inventory and condition survey of rangelands in the north eastern Goldfields, Western Australia. Bibliography. ISBN 0 7309 5997 X. 1. Pastures - Western Australia. 2. Rangelands - Western Australia. I. Van Vreeswyk, AM. E. (Alexandra Margaretha Elisabeth), 1963-. II. Gilligan, S.A (Stephen Ambrose), I 1952- . III. Western Australia. Dept. of Agriculture. Ii IV. Title. (Series: Technical bulletin (WestemAustralia. II Dept. of Agriculture); no. 87). I: 633.202099416 ii Contents Page Abstract and recommendations .......................................................................... 1 Introduction............. ............. .................. ........ .............. ........... ................. .............. 5 Review ..................................................................................................................... 9 Land use history.. ................. .................... ..................... ........ ............... ......... 11 Climate............................................................................................................ 15 Hydrogeology ................................................................................................ 36 Regional vegetation ...................................................................................... 59 Declared plants and animals ....................................................................... 62 Native fauna .................................................................................................. 67 The survey.................. ........ .............................. ............... .............. ............. ............. 75 Methodology .................................................................................................. 76 Geomorphology ............................................ ,............................................... 86 Soils ................................................................................................................. 98 Vegetation....................................................................................................... 118 Ecological assessment ................................................................................... 128 Land systems ................................................................................................. 171 Resource condition ........................................................................................ 293 Acknowledgements ................................................................................................ 305 Appendices .............................................................................................................. 306 1. Plant species lists ................................................................................. 306 (i) Perennial plant spedes recorded in the survey area............. 307 (ii) Common perennial plants in the survey area ...................... .. 319 (iii) ~c:~~~~h:c~~~~:'!e:.~~~~.:~~.~~':':~r..~~.~.~~:~.~~ ... 321 (iv) Lichens and mosses collected in the survey area .................. 323 2. Land system maps (1:250,000 scale) ................................................. 306 iii Abstract and recommendations Scope of the survey L The area surveyed covers about 100,570 kIn1 and includes all of the Menzies, Edjudina, Leonora, Laverton, Sir Samuel and Duketon 1:25(),O()() scale map sheets. The area encompasses most or ali of the following salt lake systems: Lake Ballard, Lake Rebecca, Lake Marmion, Lake Raeside, Lake Darlot and Lake Carey. There are no major river ca tchments in the area. 2. Pastoralism is the most extensive land use in the survey area, covering approximately 83,322 kIn' (83%). Mining is an important land use, occurring generally as isolated pockets of intense activity, particularly along greenstone belts traversing the survey area. Areas set aside for nature conservation at the time of survey (overed approximately 924 km' (less than 1 % of the area), consisting of Wanjarri Nature Reserve and part of Goongarrie National Palk 3. Tills report includes brief accounts on background information (such as the size and location of the survey area), land use history, climate, hydrogeology, a review of previous vegetation surveys and research, declared plants and animals, and native fauna. More detailed accounts are then provided of the survey methodology, and the geomorphology, soils, vegetation, ecological assessment, land systems and resource condition (in terllkS of pastoral impact) of the survey area. Plant species lists and land system maps are presented as appendices. 4. Sampling was conducted at the land unit scale. Land unit descriptions in terms of landform, soils, vegetation and 'site type' provided the building blocks for preparing land system descriptions. Ecological assessment was addressed according to site types, with site types representing an ecological classification in wl-deh a limited number of physical environmental variables were used with perennial plant species composition to derive a plant community I soil type Ilandform classification. Land systems are grouped according to landforms and drainage patterns into nine 'land surface types' in the 'Geomorphology' chapter and into 17 broad land types according to geology, landforms, soil types .nd vegetation in the 1:250,000 land sys tern maps accompanying this report. Sixty land systems, six soil groups (and 25 soil subgroups) and 36 site types are described for this survey area. S. Resource condition statements are provided for the whole survey area and for each land system. These are derived from visual traverse assessments. These assessments are shown on the 1:250,000 land system map sheets attached. Severely degraded and . eroded areas have been mapped. There are also condition statements for l() of the major site types based on quantitative data collected at condition sites. 6. A companion report' focussing on pastoral resources and pastoral management has a Iso been produced, based on the findings of this rangeland survey. It includes much of the information primarily related to pastoralism that has previously been included in rangeland survey reports. Pastor.lists are encouraged to refer to both reports. This report deals more specifically with resource description and assessment, recognising the widespread impact of pastoralism on resources in the process. The biophysical resources 7. The landform patterns in the survey area comprise extensive sandplain, (locally with near parallel sand ridges), sub-parallel greenstone belts and breakaways with often extensive lower pediments which give way to level to very gently inclined sheetflood plains draining into salt lakes. Relief is subdued, and drainage is generally disorganised and endoreic. This regional characterisation reflects a very old landscape that has not experienced the rejuvenation of glacial events in the Pleistocene that have overwhelmingly influenced current landforms in the northern hemisphere. Here, the landform patterns are best appreciated in terms of a morphotectonic setting of --_._.- .... - -_.... - --_.... - ---... - .... ~- 1 Pringle, H.J.R. (1994). Pastoral resources and their managementin the north-eastern Goldfields, Western Australia. Department of Agriculture, Western Australia, Miscellaneous Publication No. 22/94 1 greenstone belts surrounded by extensive granitoid expanses that have undergone deep weathering in the Mid to Early Cenozoic and have been largely preserved with the onset of aridity in the Late Cenozoic, with some modification by erosion and deposition. The survey area has severa) natural characteristics that help protect the landscape against inappropriate land use practices. These include widespread stony mantles on pediments, extensive nearly level plains subject to episodic sheet flow with tall shrub strata largely unaffected by grazing, and a dearth of