Land Systems of the Kimberley Region WA Part 6.Pdf
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Land systems of the Kimberley Region MANDEVILLE LAND SYSTEM (Mnv) 242 km2 Source: WKY Broad rocky ridges with low open woodlands and curly spinifex and sandy lowlands with tall woodlands. State land type: Hills and lowlands with eucalypt woodlands and spinifex. Geology: Dipping quartzite and sandstone of Upper Proterozoic age, and lateritized basaltic rocks of Upper Proterozoic or Lower Cambrian age; Quaternary aeolian sands. Geomorphology: Land system formed by dissection of the Kimberley surface - plateaux and mountain ranges: broad, rocky ridges up to 1.6 km wide and extending along the strike for up to 10 km; lower, gently sloping sandy interfluves, and valley floors with restricted ill- drained depressions; moderately dense rectangular pattern of strike-controlled drainage; relief up to 150 m. Land management: Rocky ridges (unit 1) poorly accessible, other parts support ribbon grass and curly spinifex pastures which are moderately favoured by cattle; resilient under controlled stocking and not prone to erosion except for some valley floors with duplex soils which are moderately susceptible. Currently this area is not under an active grazing lease. The distinctive pattern of the Mandeville land system is derived from linear quartzite ridges interspersed by sandy interfluves and valley floors. Width of this 2004 aerial photograph is about 10 km. Photo: Landgate Stylised block diagram showing location of land units 154 Land systems of the Kimberley Region MANDEVILLE LAND SYSTEM (Mnv) – land units Approx. Unit area Landforms Soils* Vegetation* Pasture type+ (%) 1 24 Ridges: up to 150 m Mainly outcrop. Low depauperate CAHP 80% high; rounded rocky woodland with moderately XXNP 20% crests and boulder- dense shrubs and Triodia strewn slopes up to bynoei. 50%. Corymbia cadophora, Adansonia gregorii, C. dichromophloia community (32). 2 40 Interfluves: up to 12 m Deep yellow sands Tall grassy woodland with CSPP 50% high and 3.2 km wide, on laterite: Pago smaller tree layer, RGRP 50% extending along the family (8). abundant shrubs and strike for up to 8 km; Triodia bitextura, sandy crest slopes less Chrysopogon spp., and than 1%, and marginal Chrysopogon spp. ground slopes up to 25%, with storey. Eucalyptus miniata low, discontinuous, alliance (20a). laterite breakaways. 3 20 Valley floors: up to Mainly mottled Open grassy woodland of RGRP 1.6 km wide; sandy yellowish loamy coolibah trees with slopes mainly less than soils: Elliott family Chrysopogon spp. E. 0.2%, locally up to 1%, (6). Greyish to microtheca alliance (20a). strewn with pisoliths. brownish sands and loams over tough clays: Hooper family (20). 4 7 Ill-drained Mottled yellowish Fringing woodlands and CSPP depressions: linear, up sandy soils: paperbark thickets. to 800 m wide and Tableland family (5). Communities 26, 36. 3.2 km long; flat, With brownish, hummocky floors and mottled powdery short marginal slopes sandy soils over up to 1%. tough mottled loamy subsoils: Tarraji family (18). 5 2 Alluvial drainage Clayey alluvial soils: Open grassy woodland FRGP floors: up to 400 m Fitzroy family (22). with frontage grass. wide, gradients 1 in 200 Corymbia bella community to 1 in 500. (22a). 6 7 Channels: up to 60 m Channels, bed-loads Fringing forests and FRIP wide and 4.5 m deep. of deep sand, woodlands. Banks, brownish E. camaldulensis, loamy alluvial soils: Terminalia platyphylla Robinson family fringing community (42). (21). * Numbers in brackets refer to soil family or vegetation community/alliance in ‘General report on lands of the West Kimberley area, WA’ (Speck et al. 1970). + Pasture types described in Appendix 1. 155 Land systems of the Kimberley Region MANDORA LAND SYSTEM (Mda) 238 km2 Source: UNP* Bare salt pans and highly saline alluvial plains subject to regular inundation supporting low shrublands of samphire and melaleuca. State land type: Coastal plains, cliffs, dunes, mudflats and beaches; various vegetation types. Geology: Quaternary alluvial and lacustrine deposits – sand, silt, clay and minor gypsum. Geomorphology: Depositional surfaces; saline paleo-drainage plains and minor channels terminating in Lake Mandora. Land management: Unique alluvial system subject to regular flooding, mixed vegetation melaleuca and samphire shrublands, spinifex and mangroves, also unvegetated saline lake flats; low pastoral value. Likely to have high conservation value as wetlands. The distinctive patterns of the Mandora land system are a complex of alluvial plains, saline plains, bare salt lakes, channels and pools. Width of this 2004 aerial photograph is about 12 km. Photo: Landgate Stylised plan diagram showing arrangement of land units * Mapped by Cotching (2005), but not described in report. Originally described by McKenzie (1985) and reported in Anna Plains Station Rangelands Resource Survey Report (1985) DAWA, unpublished. 156 Land systems of the Kimberley Region MANDORA LAND SYSTEM (Mda) – land units Approx. Unit area Landforms Soils* Vegetation Pasture type+ (%) 1 25 Alluvial plains: subject Probably sandy Shrublands of Melaleuca SSPP 50% to occasional flooding duplexes (400) and lasiandra and M. HSPP 50% sandy earths (460). glomerata, Acacia bivenosa, Hakea microneura and Santalum acuminatum with understorey of Triodia pungens and T. basedowii. 2 45 Saline plains:subject Saline wet soil Low shrublands of SMPP to regular flooding (101). Tecticornia halocnemoides, T. indica and Sesuvium portulacastrum and a few grasses. 3 25 Bare areas, salt lakes: Salt lake soil (102), No vegetation or XXNP inundated for Saline wet soil occasionally very scattered extended periods (101). samphire shrubs. 4 5 Channels and pools Unknown. Nil or fringing vegetation of XXNP mangroves and/or melaleucas. + Pasture types described in Appendix 1. * Numbers refer to Soil Groups of Western Australia (Schoknecht 2002). 157 Land systems of the Kimberley Region MANNERIE LAND SYSTEM (Mnr) 433 km2 Source*: PRP, BRM Seepage areas on inland margins of paleo-tidal plains supporting melaleuca thickets and halophytic shrublands. State land type: Alluvial plains with mixed woodlands/shrublands and mixed grasses. Geology: Quaternary supratidal mudflat deposits: clay, silt and sand. Geomorphology: Depositional surfaces; level plains with seepage areas and swamps on saline alluvium, minor sandy banks; no organised drainage features. Land management: The system is subject to inundation and waterlogging and supports very dense shrublands making access difficult. The main unit of the Mannerie land system consists of dense thickets (green) of paperbark (Melaleuca lasiandra) on seepage areas flanking the seaward margins of the sandplains of Yeeda or Nita land systems. Width of this 2004 aerial photgraph is about 2.5 km. Photo: Landgate 2004 Stylised plan diagram showing arrangement of land units * This land system is described in the Pilbara Ranges Report (Van Vreeswyk et al. 2004) and the Broome Shire report (Cotching 2005). The descriptions differ, and the Pilbara Ranges Report description is presented here as it is more representative of the entire occurrence of this land system. 158 Land systems of the Kimberley Region MANNERIE LAND SYSTEM (Mnr) – land units Approx. Unit area Landforms Soils++ Vegetation Pasture type+ (%) 1 25 Saline plains: level Grey calcareous Scattered to moderately SMPP**** 80% plains up to 3 km in loamy earths (542). close low or mid height APXG 10% extent or as smaller shrublands of Tecticornia MACP*** 10% patches within seepage spp. (samphire), Frankenia zones (unit 2), surfaces spp. (frankenia), often with saline or Trianthema turgidifolia with carbonate occasional taller shrubs encrustations. Acacia ampliceps (black wattle), Melaleuca lasiandra and grass Sporobolus virginicus (salt water couch). Occasionally mixed grasslands. 2 60 Seepage zones and Grey calcareous Moderately close to closed DMES 80% swamps: level tracts up shallow loams (542) tall shrublands or low MACP*** 20% to 6 km in extent, and grey deep woodlands of Melaleuca subject to inundation loamy duplex soils lasiandra or Acacia and with water table (509). ampliceps, understoreys very close to surface. absent or very sparse, occasional patches of grass Sporobolus virginicus. 3 15 Sand sheets and Red deep sands Scattered to moderately SSSG 80% banks: level plains and (445) with some red close shrublands of Acacia BUGP** 20% sandy banks as patches sandy earths (463). and Melaleuca spp., other up to 1 km in extent or shrubs and prominent as plains up to 500 m ground layer of Triodia wide on outer landward pungens (soft spinifex) and margins of the system, occasionally Cenchrus hummocky surfaces ciliaris (buffel grass). elevated up to 1 m above saline plains and seepage zones (units 1 and 2). + Pasture types described in Appendix 1. ++ Numbers refer to Soil Groups of Western Australia (Schoknecht 2002). ** BUGP is equivalent to APBG in Pilbara report (Van Vreeswyk et al. 2004). *** MACP is equivalent to SPSG in the Pilbara report (Van Vreeswyk et al. 2004). **** SMPP is equivalent to PSPS in the Pilbara report (Van Vreeswyk et al. 2004). 159 Land systems of the Kimberley Region MARGARET LAND SYSTEM (Mrg) 1702 km2 Source: WKY Rocky plateaux and ridges and lower slopes, spinifex and stunted open woodlands. State land type: Hills and lowlands with eucalypt woodlands and spinifex. Geology: Laterised or relatively unweathered subhorizontal or gently dipping quartzite, sandstone, and shale of Upper Proterozoic age. Geomorphology: Formed by dissection of the Kimberley surface - plateaux and mountain ranges: rocky plateaux