Marong map unit Qag

Back to: A Land Capability Study of the Rural City of Marong

Map Unit:	Quaternary alluvium, drainage depression	Map Unit Symbol:	Qag
		% of Study Area:	1.6

Land-form diagram for Marong map unit Qag

General Description:
The drainage depressions within the main alluvial plain are usually in the form of swamps or creeks such as Myers Creek. The soils associated with the creeks have not been described due to their highly variable nature and narrow coverage. The soils associated with the swamps are duplex with grey clay loam top soils and yellowish brown heavy clay subsoils. Minor variations include redder subsoils in less frequently wet areas, gradational soils and profiles with more uniform textures throughout. The creeks are often saline due to run off from the lower catchments, while the swamps are not.

Site characteristics:

Parent material age:	Quaternary	Depth seasonal watertable:	0 m
Lithology:	Alluvium	Potential recharge to groundwater:	Low
Landform Pattern:	Alluvial plain	Flooding risk:	High
Element:	Swamp	Drainage:	Poorly drained
Slope common:	0.5%	Depth to hardrock:	> 2 m
Slope range:	0-1%
Rock outcrop:	0%

Major vegetation: Red Gum, Grey Box, Yellow Box, Peppercorn, Round-leaf Wattle, Tussock grass, Rye Grass, Wallaby Grass.

Present land use: Partially forested, grazing sheep & cattle (major) cropping (minor)

Land degradation:	Water erosion		Wind erosion	Salting	Acidification
Land degradation:	Sheet/rill	Gully	Wind erosion	Salting	Acidification
Susceptibility	Low	Moderate	High	Low	Moderate
Incidence	Low	Low	Moderate	Low	Low

Soil profile characteristics:

Permeability (measured - average, range):	-
Permeability (estimated):	Very slow
Available water capacity:	279 mm H₂O
Linear shrinkage (B horizon):	15.0 %

Soil profile description:

A1	0-10 cm	Greyish yellow brown (10YR4/2) fine sandy clay loam, weak structure, subangular blocky peds less than 2 mm, smooth fabric, very weak consistence, high organic matter, pH 6.6, Clear transition to
A2	10-26 cm	Greyish yellow brown (10YR5/2) fine sandy loam, a few faint fine red mottles, moderate structure, subangular blocky peds 10-20 mm, smooth fabric, moderately firm consistence, a few iron segregations, pH 6.6. Clear transition to
B21	26-115 cm	Dull yellowish brown (10YR5/3) heavy clay, moderate structure, angular blocky peds 10-20 mm, smooth fabric, pH 6.9. Gradual transition to
B22	115-156+ cm	Dull yellowish brown (10YR5/3) light clay, strong structure, angular blocky peds 10-20 mm, smooth fabric, pH 7.1.

Soil classification:

Factual Key (Northcote):	Dy2.22 (major) Gn3.92/3, Gn3.52, Uf2 (minor)
Australian Soil Classification:	Chromosolic, Oxyaquic, Hydrosol; very deep, medium, clay loamy, non-gravelly
Unified Soil Group:	CL

Interpretation of soil analyses*

Horizon	pH	Gravel %	E.C. (salts)	Nutrient Status	P	K	Al	Organic Matter	Dispersibility
A1	6.6	6.7	VL	VH	D	S	S	H	L
A2	6.6	1.3	VL	M	S	S	S	L	H
B21	6.9	< 1	VL	H	D	S	S	VL	M
B22	7.1	< 1	VL	M	D	S	S	VL	M

VL : Very Low; L : Low; M : Moderate; H : High; VH : Very High; D : Deficient; S : Satisfactory; T : Toxic; **: Acid * See Appendix 4 for analytical results

Land capability assessment

Land Use	Class	Major limiting feature(s)/ landuse
Agriculture (CTS values)	C₃T₁S₅	High seasonal watertable
Effluent disposal (septic tanks)	5	Poor drainage, very slow permeability, high risk of flooding
Farm dams (earthen)	5	High seasonal watertable
Building foundations - slab	5	Poor drainage, high seasonal watertable, high risk of flooding
Building foundations - stumps/footings	5	Poor drainage, high seasonal watertable, high risk of flooding
Secondary roads	5	High risk of flooding, high seasonal watertable, very poor drainage
Urban residential	5	Secondary roads, building foundations
Rural residential	5	Farm dams effluent disposal, secondary roads, building foundations

The high resolution PDF file provided on this page can be viewed using the free Adobe PDF reader, this software can be installed for free from the Adobe website (external link).

A Land Capability Study of the Rural City of Marong - map unit Qag - (PDF - 42 KB)

Page top