Soil/Landform Unit 49

Undulating rises near Mount Doran

Area:

217 ha

0.02% of CMA region

The undulating rises of Quaternary volcanics in the Myrniong and Mount Doran areas are located in the east of the Corangamite catchment. Over 90% of the land here is cleared for private use. The main vegetation classes are Valley Grassy Forest, Heathy Dry Forest and Plains Grassy Woodland.

Eucalyptus ovata

E. viminalis, E. rubida

and

E. obliqua

are the dominant species for this basaltic landscape. The weathered basalt has moderate inherent fertility levels and a moderate water holding capacity. In the past the forest has provided sawn timber, posts and firewood. Current land use is mainly grazing and cropping (cereal). Soils of the slopes and plains include acidic and neutral mottled black texture contrast soils. There are minor areas of neutral mottled black texture contrast soils with a conspicuously bleached subsurface horizon, and acidic mottled yellow texture contrast soils. Areas of gilgai microrelief occur where the soils of the mounds and depressions are acidic mottled black texture contrast soils. Neutral black texture contrast soils may occur on gilgai mounds. Sheet and rill erosion, as well as periodic waterlogging, are the main degradation features of these basaltic rises.

Looking south of Lal La Reservoir towards Mount Doran

Component	1	2	3
Proportion of soil-landform unit	95%	3%	2%
CLIMATE Rainfall (mm)	Annual: 690
Temperature (^oC)	Minimum 7, Maximum 18
Precipitation less than potential evapotranspiration	October-March
GEOLOGY Age and lithology	Quaternary basalt, Orodivician marine shale and sandstone
Geomorphology	2.1.4 Dissected Western Uplands associated with volcanic landforms
LANDUSE	Uncleared: Nature conservation; water supply Cleared: Sheep and beef cattle grazing; cropping (cereal)
TOPOGRAPHY Landscape	Undulating rises
Elevation range (m)	391-450
Local relief (m)	2
Drainage pattern	Dendritic
Drainage density (km/km²)	2.2
Landform	Hillslope	Undulating plain	Hillslope
Landform element	Long gentle upper slopes	Mounds and depressions	Stony rise
Slope and range (%)	1 (1-3)	1 (1-2)	3 (2-5)
Slope shape	Straight	Straight	Concave
NATIVE VEGETATION Structure	Valley Gressy Forest (7.1%), Heathy Dry Forest (2.8%), Plains Grassy Woodland (0.2%)
Dominant species	E. ovata, E. viminalis, E. rubida, E. obliqua
SOIL Parent material	In situ weathered basalt	Alluvium	In situ weathered basalt
Description (Corangamite Soil Group)	Mottled black, brown, yellow and grey sodic texture contrast soil, coarse structure (35)	Mottled black crackin gclay soil, coarse structure (31)	Red shallow stony gradational soil (40)
Soil type sites	SW86, SW90, SFS19c	CLRA15, SW37, CLRA48	BD5, SW96, SW26
Surface texture	Clay loam	Clay	Clay loam
Permeability	Moderate to low	Moderate	High
Depth (m)	1.5	1.5	0.5
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Hardsetting surfaces, dispersible subsoils, and slow permeability results in overland flow and periodic waterlogging. Overland flow inadvertently causes sheet and rill erosion.	Clay soils beside creeks are prone to waterlogging. Streambank undercutting and streambank erosion can occur with excessive rains and inadequate ground coverage.	Overland flow is likely to cause sheet and rill erosion. Nutrient decline is possible due to shallow and permeable soils.

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