Soil/Landform Unit 188

Sequence of swamps, lakes and sedimentary plains near Leslie Manor

Area:

10 742 ha

0.80% of CMA region

This unit consists of near level plains in the Bookar and the Leslie Manor areas on the western shore of Lake Corangamite, between Camperdown and Lismore. As part of the Western Plains, the sedimentary plains are situated with stony rises to the north (Unit

112

) and basaltic low hills to the south (Unit

111

). The major occurrence of this unit is dissected by valleys of swamps and

lunettes

(Unit

201

). Soils are alkaline (strongly

sodic

) brown and grey texture contrast soils (

Sodosols

). Restricted site drainage makes these soils susceptible to waterlogging, depending on surface soil depth. Structure decline may also be a concern, as are the strongly sodic subsoils. Land use is dominantly grazing with annual rainfall variations across the unit influencing intensity of grazing (some dairying) and some cropping.

These heavy soils on level plains near Lake Terangpom have surface water removed by a number of drains leading to the lake
	Plains east of Mount Myrtoon

Component	1	2	3
Proportion of soil-landform unit	85%	10%	5%
CLIMATE Rainfall (mm)	Annual: 620
Temperature (^oC)	Minimum 8, Maximum 19
Precipitation less than potential evapotranspiration	October–March
GEOLOGY Age and lithology	Neogene fluvial-marine gravel, sand and silt, Quaternary basalt and alluvium
Geomorphology	6.2.4 Plains, rises and low hills of the Sedimentary Western Plains
LANDUSE	Uncleared: Water supply; nature conservation Cleared areas: Sheep and beef cattle grazing; cropping
TOPOGRAPHY Landscape	Level plains
Elevation range (m)	113–147
Local relief (m)	1
Drainage pattern	Centripetal
Drainage density (km/km²)	1.3
Landform	Plains	Drainage lines
Landform element	Plain	Drainage depressions	Drainage lines
Slope and range (%)	0 (0–1)	0 (0–1)	1 (0–2)
Slope shape	Linear	Concave	Concave
NATIVE VEGETATION Ecological Vegetation Class	Plains Grassland / Plains Grassy Woodland Mosaic (1.5%)
SOIL Parent material	Gravel, sand and silt	Gravel, sand, silt and clay	Gravel, sand, silt and clay
Description (Corangamite Soil Group)	Alkaline mottled brown, grey or yellow texture contrast soil (14)	Alkaline mottled brown, grey or yellow texture contrast soil (14)	Alkaline mottled brown, grey or yellow texture contrast soil (14)
Soil type sites	SW99, OTR734, MM204	SW99, OTR734, MM204	SW99, OTR734, SW88
Surface texture	Fine sandy loam	Fine sandy loam	Fine sandy loam
Permeability	Low to moderate	Very low	Very low
Depth (m)	<2	> 2	> 2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Large texture contrast between surface and subsoil with contrast in water holding capacity, permeability and nutrient holding capacity. Strongly sodic subsoil, sometimes surface soil, hardsetting when dry, limited structure. Little relief; Imperfect to poor site drainage.	Large texture contrast between surface and subsoil with contrast in water holding capacity, permeability and nutrient holding capacity. Strongly sodic subsoil, sometimes surface soil, hardsetting when dry, limited structure. Very poor site drainage.	Large texture contrast between surface and subsoil with contrast in water holding capacity, permeability and nutrient holding capacity. Strongly sodic subsoil, sometimes surface soil, hardsetting when dry, limited structure. Poor to very poor site drainage.

Page top