Location: Mt Pollock
Australian Soil Classification: Calcic, Self-Mulching, Brown VERTOSOL
Site Description: Southern Farm Systems (SFS) field day raised bed demonstration site.
Land Use: Canola crop.
SFS12 Landscape. Also shows the Map Units within the Gnarwarre SFS trial site (Adcock, 1998).
Soil Profile Morphology:
Surface Soil | SFS12 Profile | ||
Ap | 0-20 cm | Very dark greyish brown (10YR3/2); self-mulching surface condition; light medium clay; fine to medium friable structure; very firm to strong consistence dry; pH 5.5; sharp change to: | |
Subsoil | |||
B21tg | 20-30/60 cm | Very dark grey (10YR3/1) with prominent common strong brown (7.5YR4/6) mottles as well as distinct common light grey (2.5Y7/2) and yellow (2.5Y7/6) mottles; medium heavy clay; very coarse prismatic, parting to fine prismatic, parting to blocky structure; irregular smooth faced peds; pH 6.7; gradual and irregular change to: | |
B22ss | 30/60-90 cm | Dark grey (5Y4/1) becoming dark greyish brown (2.5Y4/2); light medium clay; coarse slickensides evident; pH 8.5; gradual change to: NOTE: most moisture is at this depth (base of cracks). | |
B23g | 90-130 cm | Pale olive (5Y6/4) with fine to coarse olive yellow (2.5Y6/6) mottles; sandy light clay; massive apedal structure; friable consistence moist; very few coarse calcium carbonate concretions; slight effervescence at B22/B23 junction; pH 9.1. |
pH | Salinity Rating | |||
Surface (A1 horizon) | Strongly Acid | Low-Medium | Non-Sodic | None1 |
Subsoil (B21 horizon) | Slightly Acid | Low-Medium | Sodic | Strong |
Deeper Subsoil (at 1 m) | Very Strongly Alkaline | Medium-High | Strongly Sodic | Strong |
| The salinity rating is low to medium in the surface and upper subsoil, becoming medium to high in the deeper subsoil. | The surface is non sodic. The subsoil is sodic becoming strongly sodic with depth. | The clay content is moderate throughout the profile. |
Horizon | Horizon Depth (cm) | pH (water) | pH (CaCl2) | EC dS/m | NaCl % | Exchangeable Cations | |||
Ca | Mg | K | Na | ||||||
meq/100g | |||||||||
Ap | 0-20 | 5.5 | 4.9 | 0.20 | 7.0 | 5.6 | 0.43 | 0.92 | |
B21 | 20-30/60 | 6.7 | 5.7 | 0.25 | 5.5 | 7.9 | 0.66 | 3.3 | |
B22 | 30/60-90 | 8.5 | 7.9 | 0.67 | 0.09 | 6.7 | 11 | 0.6 | 6.5 |
B23 | 90-130 | 9.1 | 8.3 | 0.56 | 0.08 | 4.9 | 9.6 | 0.3 | 6.4 |
Horizon | Horizon Depth (cm) | Exchangeable Aluminium mg/kg | Exchangeable Acidity meq/100g | Oxidisable Organic Carbon % | Total Nitrogen % | 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) |
Ap | 0-20 | 14 | 12 | 1.6 | 0.15 | 28.2 | 15.2 | 18 | 29 | 16 | 34 |
B21 | 20-30/60 | 8.1 | 35.1 | 18.9 | 14 | 26 | 17 | 40 | |||
B22 | 30/60-90 | <5 | 48.2 | 25.7 | 10 | 19 | 16 | 53 | |||
B23 | 90-130 | 15 | 35 | 15 | 35 |