PVI 7

Site: PVI 7	Land Unit: Monivae Basalt
*Aust. Soil Class.:* Melanic (& Ferric), Eutrophic, Brown CHROMOSOL (thick, moderately gravelly, clay loamy surface) (confidence level 1)

General Land Unit Description:
The level to gently undulating basalt plains between Branxholm and Glenthompson consist of an association of Vertic or Ferric Brown Chromosols and Ferric Brown Sodosols. The Chromosols typically occur on the upper slopes and crests of very slight rises that may have scattered surface boulders, and Sodosols on the lower slopes and depressions. Sodosols or Vertosols, occasionally with a sporadic bleached subsurface horizon, are usually found in open depressions or drainage lines.

Site Description:

Geology: Quaternary basalt	Landform pattern: Level to gently undulating plain
Position in landscape: Near slope of low rise	Internal drainage: Moderately well drained

Soil Profile Morphology

A1	0-20 cm	Very dark greyish brown (10YR3/2), very fine sandy clay loam, moderate to strong medium polyhedral, parting to moderate to strong fine polyhedral structure, firm consistence (dry), many (30%) ferruginous nodules (2-5 mm), well structured uncultivated, pH 5.7. Clear change to:
A21	20-30 cm	Brown (10YR5/3), sporadically bleached, clay loam (very fine sandy), moderate coarse blocky, parting to moderate medium blocky structure, firm consistence (dry), pH 6.2. Gradual change to:
A22	30-40 cm	Brown (10YR5/3) with few faint yellowish brown (10YR5/6) mottles, light clay (very fine sandy) , strong consistence (dry), pH 6.5. Clear change to:
	Subsoil
B21	40-55 cm	Brown (10YR4/3) with few (10%) yellowish brown (10YR5/4) mottles, medium clay, moderate medium polyhedral, parting to moderate fine polyhedral structure, strong consistence (dry), few (5%) ferruginous nodules (2-10 mm), pH 6.5. Gradual change to:
B22	55-100 cm	Brown (10YR4/3) with many (20%) brownish yellow (10YR6/6) mottles, medium clay, moderate coarse prismatic, parting to moderate to strong coarse to medium to fine polyhedral structure, few (5%) ferruginous and manganese nodules (2-10 mm), pH 6.8. Gradual change to:
B23	100+ cm	Light brownish grey (2.5Y6/2) and brownish yellow (10YR6/6), medium clay, strong consistence (moist), pH 6.5.

Key Profile Features

Strong texture contrast between surface (A) horizons and subsoil (B21) horizon
Large amount of ferruginous nodules in surface (A1) horizon

Soil Profile Characteristics

	pH	Salinity Rating	Sodicity	Dispersion
Surface soil (A1 horizon)	Moderately Acid	Low	Non-Sodic	None
Upper subsoil (40-55 cm)	Slightly Acid	Low	Non-Sodic	-¹
Deeper subsoil (at 10+ cm)	Slightly Acid	Low	Sodic	None

¹ strong dispersion after remoulding

Soil pit PVI 7 graphs

Horizon	Horizon Depth	pH (water)	pH CaCl2	EC dS/m	NaCl %	Exchangeable Cations				Ex Al mg/kg	Ex Ac meq/100g	Field pF2.5	Wilting Point pF4.2	Coarse Sand (0.02-0.2mm)	Fine Sand (0.02-0.2mm)	Silt (0.02-0.02mm)	Clay (<0.002mm)
						Ca	Mg	K	Na
						meq/100g
A1	0-20	5.7	5.0	0.09		6.1	3.6	0.29	0.40	<10		37.4	17.0	6.4	31.1	22.0	31.0
A21	20-30	6.2	5.3	0.06		5.3	3.5	0.12	0.44	<10		31.2	14.2	9.2	31.2	33.0	30.5
A22	30-40	6.5	5.5	0.06		5.2	4.1	0.09	0.58			33.0	17.2	13.5	24.6	17.5	41.0
B21	40-55	6.5	5.6	0.07		6.0	6.1	0.14	0.89		11	41.7	24.5	6.2	17.0	11.5	61.0
B22	55-100	6.8	6.0	0.11		5.7	8.4	0.20	1.5		11	49.9	30.6	3.5	7.2	11.5	76.5
B23	100+	6.5	6.0	0.23		4.3	10	0.20	3.1

Page top