Soil/Landform Unit 89

Dissected hills of the remnant ferrubinised plateau near Anglesea (top left is the township of Anglesea)

Area:

8371 ha

0.63% of CMA region

Stretching inland from the coast between Bells Beach and Moggs Creek lies a dissected plain of Paleogene sediments. Long straight slopes emanate from spurs and ridges. The coastal margins are retreating and often abut the sea as cliffs or massive landslips and earthflows.

The parent material is variable, ranging from ferruginised sediments on the ridges to relatively unweathered alluvium in the drainage lines. Thus the soils are particularly variable.

In general, plant nutrient levels are low and surface horizons are weakly structured. Plant communities are mainly open forests less than 15 m in height; the height decreases towards the coast under the influence of salt-bearing winds. The area is highly regarded for its diversity of flora. Some parts have been cleared for agriculture. The main hazards to land use are gully erosion and sheet erosion.

Long slopes retreating to coastal margins with steep cliffs
	Vegetation of the remnant plateau

Component	1	2	3	4	5	6	7
Proportion of soil-landform unit	25%	5%	10%	30%	25%	2%	3%
CLIMATE Rainfall (mm)	Annual: 600-800, lowest January (35), highest August (80)
Temperature (^oC)	Annual: 14, lowest July (9), highest February (17)
Seasonal growth limitations	Temperature: less than 10^oC (av.) july Precipitation: less than potential evapotranspiration mid October-early April
GEOLOGY Age and lithology	High variable Paleogene sediments consisting mainly of unconsolidated clayey silt, sand, gravel, tuff, tuff breccia also groundwater ironstone and sandstone
Geomorphology	6.2.2 Dissected plains, rises and low hills of the Sedimentary Western Plains and 3.3.2 Dissected low hills of the Southern Uplands
LANDUSE	Uncleared areas: Nature conservation; active and passive recreation; landscape conservation; gravel extraction Cleared areas: Beef cattle grazing on mainly unimproved pastures; residential; active recreation
TOPOGRAPHY Landscape	Moderately dissected hills lying below and on the seaward side of the ferruginised plateau
Elevation range (m)	0-195
Local relief (m)	50
Drainage pattern	Rectangular
Drainage density (km/km²)	2.7
Landform	Hills
Landform element	Exposed coastal slope	Slope and crest	Lower slope and drainage line	Middle slope	Upper slope and crest	Steep slope	Landslip
Slope and range (%)	20 (5-45)	9 (5-15)	8 (1-15)	15 (5-35)	10 (1-20)	45 (25-55)	(5-90)
Slope shape	Linear/irregular	Linear	Concave	Convex	Convex	Linear	Irregular
NATIVE VEGETATION Structure	Open forest	Open forest	Low woodland (variable)	Open forest	Open forest	Open forest	Tall woodland
Dominant species	E. obliqua, Casuarina stricta, E. sideroxylon	E. viminalis, E. radiata, E. baxteri	E. sideroxylon, E. obliqua	E. sideroxylon, E. obliqua	E. obliqua, E. sideroxylon, E. baxteri	E. obliqua, E. baxteri, E. sideroxylon	E. sideroxylon, E. obliqua, Melaleuca lanceolata, Casuarina stricta
SOIL Parent material	Calcareous sand, clay, silt, sand and gravel	Sand and gravel	Clay, silt and gravel	Clay, silt and sand, sandstone	Deeply weathered clay, silt and sand	Lateritic ironstone, sandstone	Clay, silt and sand; some aeolian sand
Description (Corangamite Soil Group)	Variable sodic texture contrast soils (27)	Grey sand soils (29)	Yellow-brown sodic texture contrast soils, coarse structure (27, 14)	Yellow-brown texture contrast soils, coarse structure (27, 15)	Mottled brown, grey, yellow and red texture contrast soils (27, 13)	Stony red gradational soils (29)	Variable sodic texture contrast soils (27)
Soil type sites	-	OTR742	OTR606	OTR499	OTR492, OTR744	-	-
Surface texture	Sandy loam	Loamy sand	Fine sandy loam	Fine sandy loam	Sandy loam	Sandy loam	Sandy loam
Permeability	Moderate	Very high	Very low	Very low	Moderate	Very high	Moderate
Depth (m)	>2	>2	>2	>2	>2	0.2	>2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Native vegetation is sensitive to salt pruning and disturbance. Highly dispersible soils on steep slopes are prone to sheet erosion, gully and tunnel erosion.	Very low inherent fertility and high permeability lead to nutrient decline.	Sodic, highly dispersible subsoils are prone to gully and tunnel erosion.	Highly dispersible soils are prone to gully and tunnel erosion. Weakly structured surface soils over slowly permeable subsoils on steep slopes are prone to sheet erosion.	Low inherent fertility, phosphorus fixation and leaching of permeable A horizons lead to nutrient decline.	Stony shallow soils with low organic content, weak structure and low waterholding capacity on steep slopes are prone to sheet erosion.	Native vegetation is sensitive to salt pruning and disturbance. Marine under-cutting of highly dispersible soils maintains active landslips and earth flows.

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