CLRA44

Location: Swan Bay Road, Queenscliff district, Bellarine Peninsula

Australian Soil Classification: Bleached-Sodic, Sodosolic, Redoxic HYDROSOL


General Landscape Description: Coastal flat
Geology: Quaternary coastal dune deposits: beach deposits, coastal and inland dunes, lunettes and swamps; sand, silt, clay, calcarenite deposits


CLRA44 Landscape. Coastal flats of Swan Bay

Soil Profile Morphology:

Surface Soil

A1	0–15	Black (10YR2/1); loamy sand; apedal single grain structure; pH 8.5; sharp boundary to:				CLRA44 Profile
A21	15–30	Brown (10YR5/3); sand; apedal single grain structure; pH 8.5; abrupt boundary to:
A22	30–55	Light olive brown (2.5Y5/6); sand; apedal single grain structure; pH 8.5; gradual boundary to:
A23	55–85	Yellowish brown (10YR5/8) with common medium faint to distinct yellowish brown mottles (10YR5/8); sand; many small to medium angular shell fragments; apedal single grain structure; pH 8.5; abrupt boundary to:
Subsoil
B1h	85–95	Dark grey (5Y4/1); sand; common small to medium angular shell fragments; apedal single grain structure; pH 8.5; abrupt boundary to:
B2	95–110	Olive (5Y4/3) with common medium faint dark yellowish brown (10YR4/6) mottles; medium clay; few distinct slickenside cutans; few medium manganiferous nodules; pH 8.5.

Soil Profile Characteristics:

Horizon	Sample Depth (cm)	pH (water)	pH (CaCl2)	EC 1:5	Exchangeable Cations
					Ca	Mg	K	Na
					meq/100g
A23/B1h/B2	55–110	7.2	7.1	3.8	6.5	5.8	1.9	7.5

Management Considerations:

• This is a sandy, alkaline soil with clay at depth. The clay can have a major effect by reducing and/or redirecting the internal drainage and restricting root growth beyond the upper horizons. Salinity is an issue in these coastal locations. Soil salinity at depth will affect deeper rooting plants and may indicate water movement restrictions. It is important not to increase the ground water level bringing the salinity closer to the surface; more efficient use of water by plants and/or deep drainage is suggested. This is also notes by the high sodium levels.
• Sodic subsoils are another key feature of many of the soils in the CMA, particularly in the drier areas. These subsoils usually have poor structure (generally as coarse domed columns). The poor structure results in dispersion (and subsequent clogging of pores), restricting water and gas movement through the subsoil. These subsoils are hardsetting and have limited opportunity for cultivation without further damage to soil structure. The application of gypsum is used to counter the effect of the sodicity. Penetration by deep-rooted crops is also useful as is minimum tillage practices which avoids bring the sodic, dispersive material to the surface.

Profile Described By: David Rees, Doug Crawford, Nathan Robinson, Keith Reynard & Grant Boyle (December 2002).