Soil/Landform Unit 91

Rugged coast cliffs and undulating plain near Point Reginald

Area:

1757 ha

0.13% of CMA region

Paleogene sediments outcrop along the coast at Moonlight Head, Rotten Point and Apollo Bay. The terrain is a deeply dissected plain fronted by steep coastal cliffs. The rainfall is high (850–1000 mm). The soils vary, ranging from old profiles with evidence of ferruginisation to young soils with little horizon development. The native vegetation appears to be more dependent on exposure to salt- and sand-laden coastal winds than on the soil type.

Casuarina luehmannii

at Rotten Point is an unusual member of the vegetative community, but most species are well adapted to the harsh environment. Clearing is confined to an area near Apollo Bay used for grazing. The area has high landscape and nature conservation values, but disused sand and gravel extraction pits at Moonlight Head and Rotten Point detract from these attributes. Once the vegetation is disturbed, reestablishment is slow and difficult, and sheet, rill and gully erosion are likely to occur.

Dissected low hills and hills south of Marengo
	Heathy scrubland leading to costal cliffs at Storm Point

Component	1	2	3	4	5
Proportion of soil-landform unit	10%	20%	30%	30%	10%
CLIMATE Rainfall (mm)	Annual: 850-1000, lowest January (40), highest July (110)
Temperature (^oC)	Annual: 14, lowest July (10), highest February (18)
Precipitation less than potential evapotranspiration	Temperature: No month less than 10^oC (av.) Precipitation: Exceeds potential evapotranspiration all months
GEOLOGY Age and lithology	Cretaceous fluvio-volcanic sandstone and mudstone	Paleogene marine sand and clay; minor Neogene fluvial sand			Recent calcareous clay and sand
Geomorphology	3.3.2 Dissected rolling low hills of the Southern Uplands
LANDUSE	Uncleared areas: Nature conservation; landscape conservation; sand and gravel extraction; forest grazing Minor cleared areas: Residential; dairy farming; beef cattle grazing often on unimproved pastures
TOPOGRAPHY Landscape	Deeply dissected uplifted plains with coastal cliffs
Elevation range (m)	0-150
Local relief (m)	70
Drainage pattern	Dendritic
Drainage density (km/km²)	2.3
Landform	Cliffs	Deeply dissected plains			Dune
Landform element	-	Lower slope	Dissected slope	Upper slope and crest	-
Slope and range (%)	70	7 (4-12)	14 (2-36)	5 (1-14)	14 (2-36)
Slope shape	Concave	Linear	Convex	Convex	Convex
NATIVE VEGETATION Ecological Vegetation Class	Open heath to tall shrubland	Open scrub	Open scrub	Low woodland	Open scrub
Dominant species	Casuarina stricta, Cassinia longifolia, HHelichrysum paralium, Casuarina luehmanii, Calocephalus brownii	E. baxteri, E. nitida, Leptospermum juniperinum, E. ovata, E. obliqua	E. baxteri, E. nitida, Leptospermum juniperinum, Casuarina luehmanii, Cassinia longifolia, E. ovata, E. obliqua	E. baxteri, E. ovata, E. nitida	Helichrysum paralium, Leptospermum juniperinum, Cassinia longifolia, Acacia verticillata
SOIL Parent material	Beach sand, some cliff detritus	Clay, silt and sand	Sand	Clay, silt and sand	Calcareous sand
Description (Corangamite Soil Group)	Stony brown gradational soils (7)	Yellow-grown gradational soils, coarse structure (29, 7)	Grey sand soils with hardpans (29)	Mottled brown, grey, yellow and red gradational soils with ironstone (29)	Brown calcareous sand soils (12)
Soil type sites	OTR732	OTR750	OTR608	OTR782	OTR415, CLRA41
Surface texture	Loamy sand	Sandy loam	Loamy sand	Sandy loam	Loamy sand
Permeability	Very high	Low	Low	Moderate	Very high
Depth (m)	0.1	>2	>2	>2	>2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Native vegetation is sensitive to salt pruning and disturbance. Dispersible soils of low water holding capacity on steep slopes with underlying rock are prone to sheet erosion. Wave undercutting and saturation of soils lead to landslides. Weakly structured sand soils are prone to wind erosion.	Highly dispersible soils are prone to gully and tunnel erosion. Weakly sructured surfaces over slowly permeable subsoils are prone to sheet and rill erosion.	Weakly structured surfaces overlying hardpans on steeper slopes are prone to sheet and rill erosion. Very low inherent fertility and leaching of permeable surfaces lead to nutrient decline.	Weakly structured surfaces and impeding ironstone layers lead to sheet erosion on steeper slopes. Low inherent fertility, phosphorus fixation and leaching of permeable surface horizons lead to nutrient decline.	Weakly structure sands subject to strong coastal winds are prone to wind erosion. Low inherent fertility, high alkalinity and rapid leaching lead to nutrient decline.

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