Location: Mt Pollock.
Australian Soil Classification: Vertic (& Ferric), Mottled-Subnatric, Grey SODOSOL
General Landscape Description: Possible alluvial fan below eruption point to east.
Site Description: Southern Farming Systems (SFS) 'Concept Farm' crop runoff trial site.
Geology: Quaternary - Newer Volcanics.
SFS3 Landscape. |
Surface Soil | SFS3 Profile. | ||
Ap | 0-10 cm | Dark brown (10YR3/3) with rusty root channel mottling; fine sandy clay loam; weakly pedal; very firm consistence dry; contains many fine ferruginous nodules; pH 6.2: | |
Subsoil | |||
B21cg | 10 – 75 cm | Dark greyish brown (10YR4/2) with brownish yellow (10YR6/6) mottles; fine gravelly clay; fine polyhedral structure; shiny ped faces; abundant fine buckshot; fragments of sub-rounded basalt (up to 100 mm diameter); pH 7.4: | |
B22 | 75 – 100/110 cm | Brownish yellow (10YR6/6) with dark grey (10YR4/1) infill in earthworm channels; sandy clay; many quartz fragments; very few ferruginous nodules; pH 9.1; wavy change to: | |
B23ss | 100/110 + cm | Greyish brown (2.5Y5/2); gravelly clay; abundant fine and coarse buckshot; slickensides present (50-100 mm in size); contains weathered basalt fragments; pH 9.0. |
Buckshot and mottling within the B21 horizon. | Plough pan at the intersection between the surface and subsoil. |
pH | Salinity Rating | |||
Surface (A1 horizon) | Slightly Acid | Low | Non-Sodic | None |
Subsoil (B21 horizon) | Slightly Alkaline | Low | Sodic | None1 |
Deeper Subsoil (at 1 m) | Very Strongly Alkaline | Low | Strongly Sodic | Strong |
The pH in the surface is slightly acid. The pH in the subsoil is slightly alkaline becoming very strongly alkaline with depth. | The salinity rating is low throughout. | 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 | 0-10 | 6.2 | 5.6 | 0.21 | 9.7 | 4.9 | 0.65 | 0.81 | |
B21g | 10-75 | 7.4 | 6.2 | 0.15 | 6.6 | 12 | 1.2 | 2.8 | |
B22 | 75-100/110 | 9.1 | 7.8 | 0.23 | 4 | 9.4 | 0.47 | 4.3 | |
B23 | 100/110+ | 9 | 7.9 | 0.35 | 0.03 | 5.5 | 13 | 0.7 | 6.5 |
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 | 0-10 | <10 | 9.7 | 2.3 | 0.21 | 31.5 | 14.6 | 16 | 38 | 14 | 29 |
B21g | 10-75 | 7.3 | 40.5 | 20.8 | 22 | 19 | 7 | 49 | |||
B22 | 75-100/110 | 1.5 | 31.7 | 14.5 | 17 | 42 | 8 | 33 | |||
B23 | 100/110+ | 2.4 | 44.9 | 21.3 | 14 | 31 | 12 | 43 |