Your gateway to a wide range of natural resources information and associated maps

Victorian Resources Online

Soil/Landform Unit 2

Landform Unit Description





Unit 2 - image a
Scarps and steep slopes are very typical within this landscape
      Area: 47 185 ha
      3.53 % of CMA region

Geomorphology map unit 2
      This land unit is situated in the north of the Corangamite catchment (Midlands) within the Western Uplands and consists of rolling low hills. The broad rounded topography is in association with a Neogene capping of sands and other unconsolidated deposits, particularly in the south of the unit. The main vegetation classes of this rolling landscape includes Heathy Dry Forest, Grassy Dry Forest, Herb-rich Foothill Forest and Valley Grassy Forest. This unit, which is predominantly a single mass, forms part of the northern (and eastern) boundary of the Corangamite catchment with well defined dendritic drainage falling to the south. The broad crests may be associated with short steep slopes and the side slopes are rolling though some slopes have deep soil and others shallower. The upland basalts form a significant border. The soils generally have a significant silt component, are shallow and strongly acidic on crests and wetter areas, and are generally low in nutrients. They are susceptible to gully and sheet erosion in cleared areas.

Unit 2 - image b
Upper slopes leading to deeply dissected valleys and drainage depressions

Unit 2 cross section
Unit 2 graph
Unit 2 - image c
Plantation of
Pinus radiata within a native vegetation stand at Garibaldi

Component
1
2
3
4
5
6
Proportion of soil-landform unit
20%
15%
35%
23%
2%
5%
CLIMATE
Rainfall (mm)

Annual: 710
Temperature (oC)
Minimum 7, Maximum 18
Precipitation less than potential evapotranspiration
October-March
GEOLOGY
Age and lithology

Cambro-Ordovician marine sandstone and shale, minor
Quaternary basalt and Neogene clay, sand and gravel.
Geomorphology
LANDUSE
Uncleared: Nature conservation; sport and recreation; residential development, softwood plantations.
Cleared: Softwood plantation; residential developement; sheep and beef cattle grazing
TOPOGRAPHY
Landscape

Rolling low hills and ridges
Elevation range (m)
180-670
Local relief (m)
100
Drainage pattern
Dendritic
Drainage density (km/km2)
3.1
Landform
Hills
Drainage line
Ridges
Landform element
Broad crests
Gentle plains and rises
Rolling hills
Moderately steep slopes
Drainage line
Ridge/ravine
Slope and range (%)
4(1-7)
4(2-7)
5(2-9)
11(3-15)
4(2-9)
25(0-50)
Slope shape
Convex
Convex
Convex
Straight
Concave
Convex
NATIVE VEGETATION
Ecological Vegetation Class

Heathy Dry Forest (36.5%); Grassy Dry Forest (5.2%); Herb-rich Foothill Forest (2.6%); Valley Grassy Forest (2.5%); Creekline Herb-rich Woodland (1.2%); Plains Grassy Woodland (1.2%)
SOIL
Parent material

In situ weathered sandstone and shale

In situ weathered sandstone and shale

In situ weathered sandstone and shale

In situ weathered sandstone and shale

Alluvium colluvium clay, silt, sand and gravel
In situ weathered sandstone and shale
Description
(Corangamite Soil Group)
Acid and neutral mottled brown, grey or yellow texture contrast soils and shallow light texture soils (25)
Acid and neutral mottled brown, grey or yellow texture contrast soils (25,26)
Acid and neutral mottled brown, grey or yellow texture contrast soils (25,26)
Acid and neutral mottled brown, grey or yellow texture contrast soils and shallow light texture soils (25)
Acid and neutral mottled brown, grey or yellow texture contrast soils (26) and brown gradational soils (34)
Shallow light textured soils and acid and neutral mottled brown, grey or yellow texture contrast soils (25)
Soil type sites
CLRA53, CLRA58, BD10
BD13, CLRA54, BD10
CLRA53, CLRA58, BD13
CLRA53, CLRA58, BD10
BD13, CLRA54, CLRA15
CLRA53, CLRA58, BD10
Surface texture
Gravelly loam
Fine sandy loam to clay loam
Fine sandy loam to clay loam
Gravelly loam
Clay loam
Gravelly loam
Permeability
High
Moderate
Moderate
High
Moderate
High
Depth (m)
<0.1
<2
<1.5
<1.5
2
<0.7
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS
Gentle slopes with low permeability leads to overland flow. This flow often creates sheet and rill erosion with major rainfall events. Leaching of salts also occur
Gentle slopes with low permeability lead to overland flow. This flow often creates sheet and rill erosion with major rainfall events. Leaching of nutrients and salts also occur.
Slopes and overland flow combine to increase the likelihood of leaching, sheet erosion and nutrient decline.
Steep slopes and overland flow combine to increase the likelihood of leaching, sheet erosion and nutrient decline
Moderate permeability soils. Overland flow often creates sheet and rill erosion wth major rainfall events. Waterlogging is periodic and gully erosion is most common here.
Steep slopes and overland flow continue to increase the likelihood of leaching, sheet erosion and nutrient decline.
Page top