Nature conservation

Biodiversity Reform

Darling Riverine Plains - subregions

Subregions of the Darling Riverine Plains Bioregion
SubregionGeologyCharacteristic landformsTypical soilsVegetation
Bogan-MacquarieBogan and Macquarie River alluvial fans of Quaternary age. Western margin is bedrock of the Cobar bioregion. Alluvial sediments from mixed Palaeozoic bedrock bury basement rock to 100m. Underlying sediments of Cretaceous and Jurassic age form part of the Great Artesian Basin.Channels, floodplains, and through flow swamps of past and present river systems. Grey and brown clays on the plains and depressions with texture contrast soils on the low rises of former levees and channels.River red gum and river cooba on the channels. White cypress pine and poplar box on coarser levees. Black box, belah, myall and lignum on floodplains. Complex patterns of common reed, cumbungi, and water couch depending on water levels in marshes. Poplar box woodland with wilga, budda, white pine, grey box, yellow box and Blakely's red gum on red soils on fan margins.
Castlereagh-BarwonExtensive plains on overlapping low angle alluvial fans of several rivers. Sediment derived from Jurassic sandstones on the Castlereagh fan and from basalts on the Namoi fan. Same structure as Bogan-Macquarie.Channels, floodplains, crevasse splays, levees, source bordering dunes and through flow swamps of past and present river systems.Grey and brown clays on the plains and depressions. Brown loamy sands, pale yellow or red sands, and texture contrast soils on the low rises of former levees and channels.River red gum on larger streams. Coolabah with occasional myall, river cooba, whitewood belah and clumps of river paperbark. Mitchell grass with few trees on clay plains. Poplar box with wilga, whitewood, belah, white cypress pine, silver-leaf ironbark and occasional brigalow on higher red soils.
Culgoa-BokharaClay plains of the alluvial fans of the Culgoa and Bokhara Rivers. All fine sediments of Quaternary age.Channels, floodplains, and swamps of past and present river systems.Grey clays on almost all landscapes.Coolabah, river cooba and lignum along channels with some river red gum. Widespread Mitchell grass on the clay plains with some saltbush, patches of gidgee, wilga, leopard wood and poplar box.
Warrambool-MoonieAlluvial fan and plains constructed by high level overflows from the Balonne River. Fine sediments of Quaternary age.Channels, floodplains, and swamps of past and present river systems.

 

These channels are usually dry but can be filled by high level flows in the Moonie and Balonne Rivers.

Grey clays on almost all landscapes.Coolabah, river cooba, eurah and lignum along channels with some river red gum. Coolabah woodland with poplar box, belah, budda, wilga and myall on the plains. Limited white cypress pine on rare sandy soils.
Narran-Lightning RidgeCretaceous sandstones and claystones on the ridges. Terminal lake basins. Extensive floodplains of grey clay and limited sands of Quaternary age. Low ridges on the sandstones, relief to 20m. Channels, floodplains, lakes and lunettes swamps of past and present river systems. These channels carry level flows in the Balonne and Maranoa Rivers.Stony red earths on the ridges. Grey clays over most of the plains with sandy soils and some texture contrast soils on levees, low sand dunes and lunettes.Silver leaf ironbark, white cypress pine, western bloodwood and mulga on the ridges. Poplar box on lower slopes with loamy soil. Coolabah, river red gum on channels and lake margins. Lignum in swamps and open water in Narran lakes.
Collarenebri interfluve

 

One land system only

Cretaceous sandstones and claystone that are a small part of the Surat Sandstones subregion in Queensland.Low rounded hills, relief to 10m, local dendritic drainage patterns.Stony red earths often with a gravel pavement. Soils become deeper down slope and accumulate calcium carbonate in drainage lines.Bimble box, wilga, white cypress pine, budda, warrior bush, ironwood, and belah with mixed grasses underneath.
Louth plainsAlluvial plains of the mid-Darling valley, confined between the Cobar peneplain and Mulga lands bioregions. Shallow Quaternary alluvial sediments over bedrock. Channel and floodplain features. Anabranch streams rare, occasional small dunes.Grey clays from channels to backplains with limited areas of higher red soils and patchy sands probably representing alluvial terraces.Coolabah, river red gum, river cooba and some black box along the channels. Canegrass and lignum in depressions, with saltbush, bluebush and grasses on backplains. Poplar box, rosewood and some black box on red soils and valley margins.
Wilcannia PlainsAlluvial plains of the mid-Darling valley, confined between the Cobar peneplain and Mulga lands bioregions. Shallow Quaternary alluvial sediments over bedrock. Channel and floodplain features. Anabranch streams present feeding valley margin lakes. Limited areas of dunes and sandplains.Grey clays from channels to backplains and on lake beds. Red soils and patchy sands probably representing alluvial terraces.Coolabah, river red gum, river cooba and black box along the channels. Canegrass and lignum in depressions, with saltbush, bluebush and grasses on backplains. Poplar box, belah, rosewood, black bluebush and black box on red soils and valley margins.
MenindeeQuaternary alluvial complex of river and lake sediments with associated aeolian landforms. Channel and floodplain features, well developed anabranch streams and overflow lakes with lunettes and extensive sandplains and low dunes.Grey clay and white sand in channels, lake beds and beaches. Brown clays on swamps, merging to red sands and some texture contrast soils on sandplains. Lunettes of white or pale yellow sand alternating with layers of pale brown pelleted clay.River red gum, river cooba and black box along the channels and lake margins. Canegrass and lignum in swamps and depressions. Saltbush, bluebush, turpentine, prickly wattle, and grasses with belah, and rosewood, on red soils. Bluebush and sandhill canegrass on lunettes.
Great Darling AnabranchQuaternary alluvial complex of river and lake sediments with associated aeolian landforms.Channel and floodplain features of the Great Darling Anabranch with overflow lakes, lunettes and extensive sandplains and low dunes. This system carries high level Darling River flows.Grey clay in channels, floodplains and lake beds. Limited areas of red sands and texture contrast soils. Lunettes of white or pale yellow sand alternating with layers of pale brown pelleted clay.River red gum on channels, black box and river cooba widespread on floodplains. Lignum and black box on lake margins. Belah, white cypress pine, prickly wattle and bluebush on lunettes.
Pooncarie-DarlingAs for the Great Darling Anabranch.This system carries low level Darling River flows.As for the Great Darling Anabranch.As for the Great Darling Anabranch.

From Morgan and Terrey 1992

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Page last updated: 26 April 2016