SW15

Location: Lake Corangamite

Australian Soil Classification: Endocalcareous, Self-Mulching, Black VERTOSOL

General Landscape Description: Lunette.
Site Description: Flat.
Geology: Quaternary aeolian deposits derived from lake bed sediments.

Landuse: Pasture grazing – sheep and beef.

Image: SW12-15 Landscape
SW15 Landscape – view of lower slope and terrace showing SW14 in foreground and SW15 in the distance to the right.

Soil Profile Morphology:

Surface Soil

A1	0-2 cm	Very dark grey (N3/0); light clay; moderately calcareous; pH 8.2; changing to:	SW15 Profile
Subsoil
B21	2-15 cm	Very dark grey (N3/0), with dark olive (5Y4/2) mottles; light clay (with silt); very coarse structure, parting to medium structure; rough fabric; contains shells; contains a few (>5 /cm²) roots; contains a few (< 1/ cm²) fine pores; moderately calcareous; pH 8.4; changing to:
B22	15-55 cm	Very dark grey (N3/0); light medium clay (with silt); coarse structure; rough fabric; contains calcium carbonate and shells; contains a few (>5 /cm²) roots; contains a few (< 1/ cm²) fine pores; moderately calcareous; pH 8.5; changing to:
B23	55-90 cm	Black (N2.5/0); light medium clay; medium prismatic, parting to coarse angular blocky structure; contains a few (>3%) soft calcium carbonate segregations; moderately calcareous; pH 9.2; changing to: NOTE: At 70-90 cm depth there is increasing Carbonaceous Marl.
B3	90+ cm	Olive grey (5Y5/2), with very dark grey (N3/0) on ped faces; light medium clay; coarse prismatic structure; contains a common amount of fragments; moderately calcareous; pH 9.6.

Soil Profile Characteristics:

	pH	Salinity Rating	Sodicity	Dispersion
Surface (A1 horizon)	Moderately Alkaline	Low to Medium	Non-Sodic	None
Subsoil (B21 horizon)	Moderately Alkaline	Low to Medium	Non-Sodic	None
Deeper Subsoil (at 90+cm)	Extremely Alkaline	Moderate to High	Strongly Sodic	None¹

¹Strong dispersion after remoulding.

Graph: SW15

The surface and the upper subsoil is moderately alkaline. The deeper subsoil becomes extremely alkaline.

The salinity rating in both the surface and the subsoil is low to medium. The salinity rating increases to high in the deeper subsoil.

Both the surface and the upper subsoil are non sodic. Sodicity increases to strongly sodic in the deeper subsoil.

Clay content is moderate throughout the profile.

Horizon	Horizon Depth (cm)	pH (water)	pH (CaCl₂)	EC ds/m	NaCl %	Exchangeable Cations
						Ca	Mg	K	Na
						meq/100g
A11	0-2	8.2	7.8	0.24		38	29	3.2	0.47
B21	2-15	8.4	7.9	0.21		35	38	2.6	0.46
B22	15-55	8.5	8	0.21		31	39	1.9	0.82
B23	55-90	9.2	8.5	0.62	0.06	3.8	38	2.1	7.4
B3	90+	9.6	8.4	0.88	0.08	1.3	26	2.1	12

Horizon	Horizon Depth (cm)	Organic Carbon g/100g	Total Nitrogen g/100g	Wilting Point pF4.2	Coarse Sand (0.2- 2.0 mm)	Fine Sand (0.02- 0.2 mm)	Silt (0.002- 0.02 mm)	Clay (<0.002 mm)


A11	0-2	4.1	0.42	37	1	25	29	18
B21	2-15			36	0	28	31	16
B22	15-55			38	0	36	23	17
B23	55-90
B3	90+

Profile Described By: Richard MacEwan, John Martin, Mark Imhof (March 1997).

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