Location: Nambrok. | Australian Soil Classification: Vertic, Mottled-Subnatric,Brown SODOSOL |
Great Soil Group: solodic | Geology: Late Quaternary prior stream deposits. |
General Landscape Description: Level plain with prior stream activity. | Mapping Unit: Denison [This soil is equivalent to Nambrok clay loam as described by Skene and Walbran (1948)]. |
Site Description: Uncultivated area beside dairy grazing paddock. |
Site GP66 Landscape |
A1 | 0-10 cm | Brown (10YR4/3); silty clay loam; weak coarse blocky structure; very firm consistence, moist; many macropores; pH 5.4; clear change to: | Site GP66 Soil Profile |
A2 | 10-20 cm | Brown (10YR5/3), conspicuously bleached (10YR7/3d); some rusty root channel mottling; clay loam; moderate coarse polyhedral structure; very firm consistence moist; pH 5.7; clear change to: | |
Subsoil | |||
B21 | 20-35 cm | Dark brown (10YR3/3) with yellowish brown (10YR5/6) mottles; medium clay; moderate coarse prismatic, parting to strong coarse polyhedral structure; contains a few (5%) iron nodules (2-4 mm in size); pH 6.0; clear change to: | |
B22 | 35-50 cm | Dark brown (10YR4/3) with (40%) brownish yellow (10YR6/8) mottles; heavy clay; moderate coarse prismatic, parting to moderate coarse blocky structure; slickensides present; pH 7.0; gradual change: | |
B23 | 50-90 cm | Light olive brown (2.5Y5/4); heavy clay; strong coarse prismatic, parting to moderate coarse blocky structure; slickensides present; pH 8.1: | |
B24 | 90+ cm | Light olive brown (2.5Y5/6); heavy clay; pH 8.9. |
Key Profile Features:
| |
Soil Profile Characteristics: |
pH | Salinity Rating | |||
Surface (A1 Horizon) | Strongly Acid | Low - Moderate | Non-Sodic | None1 |
Subsoil (B21 Horizon) | Moderately Acid | Low | Sodic | Slight2 |
Deeper Subsoil (at 90cm) | Strongly Alkaline | Low | Strongly Sodic | Slight2 |
The soil profile becomes increasingly alkaline with depth. | The surface soil is non-sodic. The sub-soil is sodic, becoming strongly sodic at 80 cm. | ||
The surface salinity levels are low to moderate. The subsoil has a low salinity rating. | The clay content increases significantly at the A/B horizon interface. |
Horizon | Horizon Depth (cm) | pH (water) | pH (CaCl2) | EC 1:5 | NaCl | Exchangeable Cations | |||
Ca | Mg | K | Na | ||||||
meq/100g | |||||||||
A1 | 0-10 | 5.4 | 4.8 | 0.28 | <0.03 | 4.4 | 3.3 | 1.2 | 0.42 |
A2 | 10-20 | 5.7 | 4.8 | 0.1 | 2.6 | 2.1 | 0.73 | 0.4 | |
B21 | 20-35 | 6 | 4.7 | 0.07 | 2.8 | 5.5 | 0.61 | 0.99 | |
B22 | 35-50 | 7 | 5.9 | 0.12 | 3.2 | 8.9 | 0.49 | 2.1 | |
B23 | 50-90 | 8.1 | 7.1 | 0.3 | 0.05 | 3 | 10 | 0.45 | 3.8 |
B24 | 90+ | 8.9 | 8.1 | 0.07 | 2.9 | 9.5 | 0.45 | 7.4 |
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) |
A1 | 0-10 | 10 | 15.7 | 4 | 24 | 31 | 32 | ||
A2 | 10-20 | 12 | 12.7 | 3 | 28 | 34 | 35 | ||
B21 | 20-35 | 43 | 19.2 | 6 | 13 | 20 | 61 | ||
B22 | 35-50 | 20.9 | 2 | 10 | 18 | 70 | |||
B23 | 50-90 | 20.4 | 1 | 10 | 19 | 70 | |||
B24 | 90+ |