Soil/Landform Unit 6

Landform Unit Description



Unit 6 image a
The 80% uncleared forested Brisbane Ranges comrpise most of this unit with a wide range of vegetation communities
      Area: 6026 ha
      0.45% of CMA region

      Rolling hills on sedimentary sediments occur as the Brisbane Ranges on the eastern boundary of the Corangamite catchment. A rich diversity of vegetation comprising 80% of this unit include the communities of Heathy Dry Forest, Grassy Dry Forest, Lowland Forest, Valley Grassy Forest, Shrubby Woodland and Creekline Herb-rich Woodland. The dominant species of these vegetation groups are Eucalyptus obliqua, E. ovata, E. radiata and E. viminalis. The steep and rocky nature of the terrain, low fertility and low water holding capacity of the soils have discouraged further clearing, except on some of the gentler, lower slopes that support native pastures. The forest in the past has provided sawn timber, posts and firewood. Soils include an association of acidic mottled texture contrast soils with structured or massive subsoils. These relatively shallow stony soils are prone to sheet erosion, while the deeper soils in the drainage depression suffer from gully erosion and soil salting.
Unit 6 geomorphology

Unit 6 image b
Steeply dissected terrain is often vegetated, however areas are
particularly vulnerable to erosion

Unit 6 cross section
Unit 6 graphUnit 6 image c
Cleared land is mainly used for grazing

Component
1
2
3
4
Proportion of soil-landform unit
2%
50%
3%
45%
CLIMATE
Rainfall (mm)

Annual: 660
Temperature (oC)
Minimum 8, Maximum 8
Precipitation less than potential evapotranspiration
October-March
GEOLOGY
Age and lithology

Ordovician marine shale and sandstone, Neogene fluvio-marine clay, sand and gravel
Geomorphology
LANDUSE
Uncleared: Water supply; nature conservation; hardwood; gravel extraction
Cleared: Sheep and beef cattle grazing; cropping (cereal); gravel extraction
TOPOGRAPHY
Landscape

Rolling hills
Elevation range (m)
130-363
Local relief (m)
65
Drainage pattern
Dendritic
Drainage density (km/km2)
4.8
Landform
Hill
Landform element
Moist protected slopes
Dry exposed slopes
Drainage line
Crest
Slope and range (%)
15 (10-30)
15 (10-30)
3 (1-4)
3 (1-6)
Slope shape
Straight
Straight
Concave
Convex
NATIVE VEGETATION
Ecological Vegetation Class

Heathy Dry Forest (34.2%), Grassy Dry Forest (24.0%), Lowland Forest (8.2%), Valley Grassy Forest (3.6%), Shrubby Woodland (3.3%), Creekline Herb-rich Woodland (3.0%)
Dominant species
E. obliqua, E. ovata, E. radiata, E. viminalis
E. obliqua, E. dives, E. radiata, E. viminalis
E. ovata, E. radiata, E. viminalis
E. obliqua, E. dives, E. radiata, E. viminalis
SOIL
Parent material

In situ weathered sandstone and shale

In situ weathered sandstone and shale

Alluvium, clay, silt, sand, gravel

In situ weathered sandstone and shale, unconsolidated sediments
Description
(Corangamite Soil Group)
Red mottled brown, grey or yellow gradational or texture contrast soils, fine structure (25/26)
Red mottled browy, grey or yellow gradational or texture contrast soils, fine strucuture (25/26)
Black gradational soil - variable (34)
Shallow stony red and bronw, grey or yellow gradational soil (25)
Soil type sites
CLRA1, OTR733
CLRA53, CLRA58, BD10
Surface texture
Fine sandy loam
Fine sandy loam
Clay loam
Gravelly loam
Permeability
High
High
Moderate to low
High
Depth (m)
1
2
>1
0.5
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS
Steep slopes and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow.
Steep slopes and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Soil compaction is also a limitation for soils with shallow topsoils.
Moderate permeability subsoils and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Soil compaction is also a limitation for soils with shallow topsoils.
Moderate slopes and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Soil compaction is also a limitation for soils with shallow topsoils.
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This page contains material sourced from the Victorian Resources Online (VRO) website, originally published by the State Government of Victoria. The content is licensed under the Creative Commons Attribution 3.0 Australia licence . The material has been adapted and re-formatted; no endorsement by the Victorian Government is implied.