Soil/Landform Unit 3

Landform Unit Description

Forestry is the dominant land use on teh north-eastern boundary of the catchment. This area is particularly important with respect to water supply catchment.	Area: 4842 ha 0.36% of CMA region
	This land unit is situated in the dissected uplands (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 vegetation classes of this rolling landscape includes Herb-rich Foothill Forest/Shrubby Foothill Forest Complex, Shrubby Foothill Forest, Sedgy Riparian Woodland and Herb-rich Foothill 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.

Open forests with deep soils on undulating slopes
	Cleared pine forestry plantation with new seedlings

Component	1	2	3	4
Proportion of soil-landform unit	20%	15%	60%	5%
CLIMATE Rainfall (mm)	Annual:1000
Temperature (^oC)	Minimum 6, Maximum 16
Precipitation less than potential evapotranspiration	October-March
GEOLOGY Age and lithology	Ordovician marine sediments with minor Recent clay, sand and gravel and basalt
Geomorphology	2.1.1 Dissected Western Uplands associated with Palaeozoic sedimentary and metamorphic rocks
LANDUSE	Uncleared: Nature conservation; water supply; sport and recreation; residential development; softwood plantations Cleared: Softwood plantations; water supply; residiential development; sheet and beef cattle grazing
TOPOGRAPHY Landscape	Rolling hills
Elevation range (m)	560-740
Local relief (m)	30
Drainage pattern	Dendritic
Drainage density (km/km²)	2.2
Landform	Hills
Landform element	Crest and steep slope	Sloep with deep soil	Slope with shallow soil	Drainage line
Slope and range (%)	12 (5-20)	10 (5-20)	20 (5-30)	2 (1-4)
Slope shape	Convex	Straight	Straight	Concave
NATIVE VEGETATION Ecological Vegetation Class	Herb-rich Foothll Forest/Shrubby Foothill Forest Complex (49.6%); Shrubby Foothill Forest (4.1%); Sedgy Riparian Woodland (3.4%); Herb-rich Foothill Forest (2.0%)
NATIVE VEGETATION Ecological Vegetation Class
Dominant species	E. obliqua, E. dives, E. radiata, E. rubida	E. obliqua, E. viminalis, E. radiata, E. rubida, E. cypellocarpa	E. obliqua, E. viminalis, E. radiata, E. rubida, E. dives	E. obliqua, E. viminalis, E. radiata, E. rubida
SOIL Parent material	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
SOIL Parent material	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
Description (Corangamite Soil Group)	Shalow stony brown gradational soils (25)	Red texture contrast and red gradational soils, fine structure (26)	Brown, grey or yellow texture contrast and brown, grey or yellow gradational soils (25)	Brown gradational (earth) soil (34)
Soil type sites	CLRA53, CLRA58, BD10	BD13, BD11, MM204	CLRA53, CLRA57, BD10	CLRA15, SW39
Surface texture	Gravelly loam	Fine sandy loam to clay loam	Fine sandy loam to clay loam	Clay loam
Permeability	High	High	Moderate to high	Moderate
Depth (m)	0.5	2	1	2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Steep slopes and low permeability leads to overland flow. This flow often creates sheet and rill erosion with major rainfall events. Leaching of salts also occur.	Steep slopes and low permeability leads to overland flow. This flow often creates sheet and rill erosion with major rainfall events. Leaching of salts also occur with nutrient decline.	Steep slopes and low permeability leads to overland flow. This flow often creates sheet and rill erosion with major rainfall events. Leaching of salts also occur with nutrient decline.	Moderate permeability and overland flow are common. Subsurface waterlogging is seasonal.. Gully erosion and leaching of salts also occur. Surface compaction can benefit from controlled traffic.

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