Cape Otway Land System

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In the vicinity of Cape Otway and extending discontinuously to the west is an elevated plain of coastal dunes. The coastal margins of the plain are generally fronted by 100 m cliffs of calcarenite with possibly small primary dunes at the base of the cliffs. Behind the cliffs, the plain has an irregular dune topography that may extend several kilometres inland. The demarcation to other land systems is very sharp and easily defined.

Woodlands of Eucalyptus viminalis with open grassy understoreys used to cover most areas, although shrubs resistant to salt- and salt-laden winds formerly colonized the coastal localities. Most areas have been cleared for grazing, but the establishment of improved pastures present difficulties. Overgrazing has resulted in severe wind erosion in some areas, and reclamation is difficult and expensive.

A Study of land in the catchments of the Otway Range and adjacent plains - cape otway

Large parts of the Cape Otway land system have been cleared
and provide rough grazing for cattle on native grasses.

Area: 36 km²	Component and its proportion of land system
Area: 36 km²	1 6%	2 4%	3 20%	4 20%	5 10%	6 40%
CLIMATE Rainfall, mm	Annual: 900 – 1,100, lowest January (45), highest July (105)
Temperature, 0^oC	Annual: 14, lowest July (10), highest February (18)
	Temperature: less than 10^oC (av.) July
	Precipitation: less than potential evapotranspiration late November - February
GEOLOGY Age, lithology	Recent sand and shell grit on a calcarenite basement
TOPOGRAPHY Landscape	Elevated longitudinal coastal dunes at and to the west of Cape Otway
Elevation, m	0 – 155
Local relief, m	15
Drainage pattern	Mainly absent; some dendritic areas
Drainage density, km/km²	0.7
Land form	Foredune	Cliff		Longitudinal dune	Interdune corridor	Inland dune
Land form element	-	-	Windward slopes	Leeward slopes	-	-
Slope (and range), %	20 (15-40)	65 (50-100)	25 (5-50)	20 (5-50)	3 (0-9)	25 (3-60)
Slope shape	Convex	Linear	Convex	Convex	Concave	Concave
NATIVE VEGETATION Structure	Tussock grassland	Open scrub	Open scrub	Woodland	Open forest	Woodland
Dominant species	Spinifex hirsutus, Scirpus nodosus, Calocephalus brownii	Casuarina stricta, Casuarina longifolia, Alyxia buxifolia	Alyxia buxifolia, Leucopogon parviflorus, Cassinia longifolia, Acacia verticillata, Leptospermum juniperinum, Helichrysum paralium	Casuarina stricta, E. viminalis, Leucopogon parviflorus	E. obliqua E. viminalis	E. viminalis
SOIL Parent material	Coarse sand, shell grit	Calcarenite, aeolian sand	Sand with calcarenite basement	Sand with calcarenite basement	Sand with calcarenite basement	Sand with calcarenite basement
Description	Yellow calcareous sand soils, uniform texture	Yellow calcareous sand soils, uniform texture	Brown calcareous sand soils, uniform texture	Brown calcareous sand soils, uniform texture	Red-yellow calcareous sand soils, uniform texture	Red-yellow calcareous sand soils, uniform texture
Surface texture	Coarse sand	Coarse sand	Loamy sand	Loamy sand	Loamy sand	Loamy sand
Permeability	Very high	Very high	Very high	Very high	Very high	Very high
Depth, m	>2	0.3	>2	>2	>2	1.9
LAND USE	Cleared areas: Beef cattle grazing on unimproved pastures; mining of calcarenite; residential; active recreation. Uncleared areas: Forest grazing of beef cattle; active and passive recreation; nature conservation; landscape conservation.
SOIL DETERIORATION HAZARD Critical land features, processes, forms	Dune inherently unstable due to cyclical marine erosion. Low fertility, low water-holding capacity and vegetation sensitive to disturbance lead to wind erosion and leaching of nutrients.	Weakly structured sand soils of low water-holding capacity on steep slopes with vegetation sensitive to disturbance and salt pruning are prone to sheet erosion by wind and water.	Weakly structured sand soils with low water-holding capacities, subjected to strong on-shore winds are prone to wind erosion. Low inherent fertility, high alkalinity and rapid leaching lea to nutrient decline.	Weakly structured sand soils with low water-holding capacities are prone to wind erosion. Low inherent fertility, high alkalinity and rapid leaching to nutrient decline.	Low inherent fertility and high permeability lead to nutrient decline.	Weakly structured sand soils with low water-holding capacities are prone to wind erosion. Low inherent fertility and high permeability lead to nutrient decline.

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