Soil/Landform Unit 189

The near-level plains support a range of land uses including dairy. Most of the land has been cleared and replaced with annual and perennial pastures

Area:

3047 ha

0.23% of CMA region

This unit of near-level plains forms part of the sedimentary Western Plains. The unit comprises a series of sub-parallel occurrences in the Carpendeit area where they act as a divide between the stony rises (Unit

113

) to the north and sandy (Neogene) sedimentary plains (Unit

181

, Hanson Plain) to the south. Native vegetation is mainly Lowland Forest and Swamp Scrub. The soils are

acidic

mottled

black texture contrast soils (

Sodosols

). Given the relatively high rainfall and topographic position, this unit is susceptible to waterlogging and

compaction

. Nutrient decline in the upper soil and structure decline (with increasing

sodocity

) are concerns.

Looking north-west over the plains towards Mount Porndon

Component	1	2	3
Proportion of soil-landform unit	30%	65%	5%
CLIMATE Rainfall (mm)	Annual: 830
Temperature (^oC)	Minimum 8, Maximum 18
Precipitation less than potential evapotranspiration	November–March
GEOLOGY Age and lithology	Neogene fluvial-marine clay, sand and gravel; Quaternary basalt and alluvium
Geomorphology	6.2.4 Plains, rises and low hills of the Sedimentary Western Plains
LANDUSE	Uncleared areas: Hardwood forestry for sawlogs, posts and poles; water supply; nature conservation Cleared areas: Dairy farming; sheep and beef cattle grazing; water supply; cropping
TOPOGRAPHY Landscape	Near-level plains
Elevation range (m)	127–153
Local relief (m)	15
Drainage pattern	Centripetal–parallel
Drainage density (km/km²)	1.0
Landform	Plains
Landform element	Long gentle slopes	Level plain	Drainage depressions
Slope and range (%)	2 (1–4)	1 (0–3)	0 (0–1)
Slope shape	Convex	Straight	Straight
NATIVE VEGETATION Ecological Vegetation Class	Lowland Forest (0.7%), Swamp Scrub (0.5%)
SOIL Parent material	Sand, clay and gravel	Sand, clay and gravel	Alluvium; clay, sand and gravel
Description (Corangamite Soil Group)	Acidic black texture contrast soils (14)	Acidic black texture contrast soils (14)	Acidic black and mottled black texture contrast soils (32)
Soil type sites	SW99, OTR606, OTR734	SW99, OTR606, OTR734	SW88, SFS2, OTR492
Surface texture	Clay loam	Clay loam	Sandy clay loam
Permeability	Low to moderate	Low	Very low
Depth (m)	<2	<2	>2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Texture contrast, low nutrient holding capacity and water holding capacity in subsurface and surface soil, higher in subsoil. Acidic (not quite strongly). Heavy, possibly expansive clay subsoil. Moderate to slow site drainage.	Texture contrast, low nutrient holding capacity and water holding capacity in subsurface and surface soil, higher in subsoil. Acidic (not quite strongly). Heavy, possibly expansive clay subsoil. Slow site drainage, higher susceptibility to waterlogging and compaction compared with Component 1.	Texture contrast, low nutrient holding capacity and water holding capacity in subsurface and surface soil, higher in subsoil. Acidic (not quite strongly). Heavy, expansive clay subsoil. Slow to very slow site drainage, higher susceptibility to waterlogging and compaction compared with Components 1 and 2.

Page top