Western Cape and Gulf
The Western Cape and Gulf Freshwater Biogeographic Province (FBP) consists of many drainage basins, including the Settlement, Mornington Island, Nicholson, Leichardt, Morning, Flinders, Norman, Gilbert, Staaten, Mitchell, Coleman, Holroyd, Archer, Watson, Embley, Wenlock, Ducie, and Normanby. The FBP is located in the north-west of the state, and covers the Cape York Peninsula, Gulf Plains, Northwest Highlands, Mitchell Grass Downs, Einasleigh Uplands vegetation bioregions, and a very small portion of the Wet Tropics and Desert Uplands vegetation bioregions.
Key ecosystem drivers Western Cape and Gulf Freshwater Biogeographic Province
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Geology & topography |
Hydrology |
Water quality |
Habitat |
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Annual Mean Precipitation ranges from wet to dry along a north-south gradient. Driest Quarter Precipitation tends to be dry and uniform across the province.
Annual mean temperature for the province ranges from hot to cool. Cool areas of the province are limited to the region.
Mean annual runoff for the province is moderate.
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The north and east sections of the province are dominated by sandstones with deep heavy grey and brown cracking clays dominating the south.
The province is primarily composed of erosional and valley bottom flatness index classes both of which dominate in different regions of the province.
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On average approximately 8% of flow is base flow and the other 92% is related directly to flood flow from rainfall events.
Modelled pre-development data from 61 gauges were used for these analyses.
Spate runoff averaged 0.012 to 0.014 Ml km2 day-1, these values were relatively steady across the province with the highest and lowest values being 0.056 and 0.001 Ml km2 day-1 respectively.
Flow is intermittent in the province and no flow spells are an important feature of the hydrology.
The mean rate of rise for the province is approximately 1.5 times the mean rate of fall.
The wet season is January-March and the dry season is April-December
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Turbidity is highly variable across the province. The majority of the region has low turbidity though in some places it can be extremely high.
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Steep, moderate and low are the predominant bank slope categories in the province. All shape categories occur, though these are dominated by the concave and convex classes.
The riparian zone is sparse and primarily dominated by grasses and medium/small trees. Macrophyte (aquatic plant) tend to occur at a third of sites and are dominated by submerged and emergent growth forms.
Substrate heterogeneity is consistent between habitat types and is high compared to other provinces in Queensland. Edge and pool habitats are dominated by sand, though all substrate categories occur in all habitats.
Large woody debris (LWD) and snags are conspicuous components of many rivers in the province.
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Last updated: 21 February 2012
— Department of Environment and Resource Management
