Location: Seaspray. | Australian Soil Classification: Grey SODOSOL (very thick sandy surface horizons). |
Geology: Tertiary sediments later overlain by Pleistocene aeolian sediments. | General Landscape Description: Dune and swale landscape. |
Mapping Unit: Gormandale with Stockdale (This soil profile more typically reflects Gormandale mapping unit). | Site Description: Lower slope of an old dune (0-5% slope) with a southerly aspect. This site occurs within native vegetation. |
Native Vegetation: Original vegetation included Manna Gum (E. viminalis), Grey Box, Yertchuk (E. consideniana), Banksia, Tea-tree (Leptospernum sp.), Bracken. |
Site GP48 Landscape. |
A11 | 0-20 cm | Very dark greyish brown (10YR3/2); loamy sand; weak medium subangular blocky, parting to fine subangular blocky structure; slight hardpan; pH 4.3; clear change to: | Site GP48 Profile. |
A12 | 20-40 cm | Dark brown (10YR3/3); loamy sand; weak structure; pH 4.5; clear change to: | |
A2 | 40-90 cm | Pale Brown (10YR6/3) conspicuously bleached (10YR8/2d); sand; massive; weak consistence dry; pH 5.6; abrupt change to: | |
Subsoil | |||
B1 | 90-95 cm | Light brownish grey (10YR6/2) with strong brown (7.5YR5/6) mottles; coarse sand; massive; strong consistence dry; clear but discontinuous change to: | |
B21 | 95-120 cm | Grey (10YR6/1) with yellowish brown (10YR5/8) mottles; light medium clay; moderate coarse prismatic, parting to moderate coarse polyhedral structure; strong consistence dry; dark organic stains along prism faces; pH 6.2; clear and wavy change to: | |
B22 | 120-140 cm | Grey (10YR5/1) with yellowish brown (10YR5/6) mottles; sandy loam (sandy); weak coarse prismatic, parting to weak coarse blocky structure; pH 6.3. |
Key Profile Features:
| |
Soil Profile Characteristics: |
Horizon | pH | Salinity Rating | ||
Surface (A11 horizon) | Extremely Acid | Very Low | Non-Sodic | None |
Subsoil (B21 at 1 m) | Slightly Acid | Moderate | Strongly Sodic | Moderate |
Deeper subsoil (at 1.3 m) | Slightly Acid | Moderate | Strongly Sodic | Slight |
The surface soil is extremely acidic. The subsoil is slightly acid throughout. | The salinity rating in the surface is very low. The level of soluble salts is moderate in the deep subsoil. | The clay content increases sharply at the A/B horizon boundary. |
Horizon | Horizon Depth (cm) | pH (water) | pH (CaCl2) | EC 1:5 | NaCl | Exchangeable Cations | |||
Ca | Mg | K | Na | ||||||
meq/100g | |||||||||
A11 | 0-20 | 4.3 | 3.6 | 0.06 | 0.63 | 0.54 | 0.12 | 0.16 | |
A12 | 20-40 | 4.5 | 3.8 | 0.07 | 0.2 | 0.39 | 0.07 | 0.26 | |
A2 | 40-90 | 5.6 | 4.6 | 0.06 | 0.16 | 0.27 | 0.06 | 0.26 | |
B! | 90-95 | ||||||||
B21 | 95-120 | 6.2 | 5.7 | 0.76 | 0.16 | 0.4 | 5.2 | 0.2 | 3.1 |
B22 | 120-140 | 6.3 | 5.8 | 0.3 | 0.06 | 0.1 | 1.8 | 0.1 | 1 |
Horizon | Horizon Depth (cm) | Exchangeable Aluminium mg/kg | Exchangeable Acidity meq/100g | Field Capacity pF2.5 | Wilting Point pF4.2 | Coarse Sand (0.2-2.0 mm) | Fine Sand (0.02-0.2 mm) | Silt (0.002-0.02 mm) | Clay (<0.002 mm) |
A11 | 0-20 | 49 | 3.1 | 59 | 30 | 6 | 3 | ||
A12 | 20-40 | 83 | 2.3 | 53 | 35 | 6 | 3 | ||
A2 | 40-90 | 17 | 1.2 | 54 | 36 | 5 | 3 | ||
B! | 90-95 | ||||||||
B21 | 95-120 | 9.4 | 17.7 | 26 | 19 | 5 | 49 | ||
B22 | 120-140 | 5.9 | 41 | 38 | 7 | 16 |