Sandy (Sy)

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Sandy - geo

Area: 41 sq. km (0.2%)

All drainage depressions in the Eastern lowlands and Baragwanath Anticline in which sandy alluvium dominates have been mapped in Sandy land system, except for areas with braided channels which are mapped in Stratford land system. This is consequently a very variable land system and most variation is dealt with on a component basis. All components are not always present in any one occurrence of the land system due to differences between streams. Streams have low gradients and at least two terrace levels, except on the Baragwanath Anticline where the downstream slopes are greater. Here there are also springs and seepage areas on the lower slopes.

Sandy soils dominate and those above normal flood levels are weakly podzolised with somewhat bleached subsurface horizons and brown subsoils which may be cemented and nodular. In lower lying parts subject to flooding the sands generally are younger with little profile differentiation beyond humus accumulation in the surface. There are some clayey parent materials and these can also differ in degree of soil development depending on flood regime. Duplex soils develop in non-inundated, better-drained areas. In areas which are poorly drained or seasonally flooded, soil development is limited to surface darkening and subsoil mottling. Wind erosion appears to be the main hazard on the sandy soils, as slopes are generally too gentle and soils too permeable for sheet erosion by water. However, the permeable soils are susceptible to leaching.

The vegetation is mainly woodland I or II, often shrubby or ferny.

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Sandy - image

A higher level terrace adjacent to the Perry River

CLIMATE Rainfall, mean (mm) Temperature, mean (°C) Seasonal growth limitations	Annual 500 - 800; lowest July (30 - 50), highest October (50 - 80) Annual 12 - 14; lowest July (8 - 10), highest February (19 - 21) Temperature <10°C (av.): June - August Rainfall < potential evapotranspiration: November – March
GEOLOGY Age, lithology	Holocene sandy alluvium; minor Tertiary gravels, sands and clays
PHYSIOGRAPHY Landscape Elevation range (m) Relative relief (m) Drainage pattern Drainage density (km/km²)	Drainage floors with predominantly sandy alluvium 20 - 120 5 - 20 Meander channel 1.7
PRESENT LAND USE	Mostly cleared: grazing of cattle and sheep on unimproved pastures; softwood plantations (limited) Minor proportion uncleared: apiculture; bush grazing (limited); small area in the Holey Plains State Park

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Sandy - cs

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Sandy - graph

LAND COMPONENT Percentage of land system Diagnostic features	1 70 High-level linear terraces only inundated by very high floods	2 15 Lower, narrow modern flood plains	3 15 Drainage areas sometimes with seepage zones
PHYSIOGRAPHY Slope %, typical and (range) Slope shape	1, (0- 2) Straight	1, (0- 2) Straight	1- 2, (0- 3) Straight
SOIL
Parent material	Sandy alluvium
Description	Deep black sand over greyish brown subsurface soil; dark brown sand or nodular coffee rock subsoil; often strongly acidic throughout	Variable; little differentiated sand to sandy clay loam, black to dark brown at the surface, greyish brown to light yellowish brown at depth; sometimes mottled	Limited observations — variable; sandy soils as in component 1; also dark greyish brown sandy loam over greyish brown mottled sandy loam with abrupt change to blocky yellowish brown clay subsoil
Classification	Incipient Podzols, Siliceous Sands Uc2.36, Uc4.23, Uc4.24	Alluvial Soils Ucl.21, Uc5.23, Um1.41	Incipient Podzols, Yellow Podzolic Soils Uc2.31, Uc4.- , also Dy2.2-
Surface texture	Loamy sand	Loamy sand to sandy or silty clay loam	Sand to sandy loam
Surface consistence	Soft when dry	Soft when dry	Soft when dry
Depth (m)	>2.0	>2.0	>2.0
Nutrient status	Very low	Very low to low	Very low to low
Available soil water capacity	Very low	Very low to moderate	Very low to moderate
Perviousness to water	Very rapid	Slow to very rapid	Slow to very rapid
Drainage	Excessive	Somewhat poor to good	Somewhat poor to good
Exposed stone (%)	0	0	0
Sampled profile number	-	-	-
NATIVE VEGETATION Structure of vegetation and characteristic species of dominant stratum (+ Predominant species)	Ferny or shrubby woodland II: E. consideniana+ or E. viminalis var. racemosa+	Limited data — probably woodland II or open forest II, often shrubby with E. globoidea+ or with E. ovata+ and E. tereticornis	Mainly shrubby woodland I, II: Species include E. radiata+, E. bridgesiana+ and E. ovata Occasionally closed forest I, II: Melaleuca ericifolia+

Disturbance	Affected process and trend	Primary resultant deterioration			Casual activities	Primary off-site process
Disturbance	Affected process and trend	Form	Susceptibility of components	Incidence with components	Casual activities	Primary off-site process
Alteration of vegetation: — reduction in leaf area, rooting depth and/or perenniality	Reduced transpiration, resulting in increased deep percolation and leaching	Nutrient loss	1; high 2; moderate 3; variable, low - high	Not determined	Removal of trees	Increased movement of water to groundwater; increased base-flow of streams
Increased exposure of surface soil	Increased wind velocity over soil and increased detachment of sand	Wind erosion	1; high 2; low - moderate 3; low	Uncommon	Clearing, burning, overgrazing, road building and other earth-moving activities, rabbit burrowing, trafficking by stock and vehicles.	Encroachment by sand
Increased physical pressure on soil	Increased compaction	Structure decline	1,3; low 2; low - moderate	Uncommon	Increased trafficking, cultivation, overgrazing, export of organic matter	-
Increased soil disruption	Increased soil break-up Increased loosening of sand	Gully erosion Wind erosion	1,2; very low 3; moderate 1; high 2; low - moderate 3; low	Uncommon Uncommon	As for wind erosion above As for wind erosion above	Increased sediment load Encroachment by sand
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