Reference soil Mozambique 05: Phaeozem

MZ005

Phaeozems occur all over the world, but especially on the more moist side of the steppe regions, bordering Chernozems.

Characteristics

Soils having a mollic horizon (deep, brownish or blackish surface horizon with a significant accumulation of organic matter and high base saturation); a base saturation of 50 percent or more between 25 and 100 cm from the soil surface; a calcium carbonate-free soil matrix at least to a depth of 100 cm from the soil surface, or to a contrasting layer between 25 and 100 cm; no diagnostic horizons other than an albic, argic, cambic or vertic horizon, or a petrocalcic horizon in the substratum.

Distribution of Phaeozems (rough estimation supplied by soilgrids)

Reference soil MZ005: Phaeozems

Brief description of the profile: A deep, well drained, dark reddish brown clay soil, strongly or moderately structured; with a thick dark coloured topsoil; subsoil aggregates fall apart when wetted. Soil when dry has a few cracks, width is less than 0.5 cm. Soil clods fall apart in very fine angular aggregates when saturated with water. At a depth of about 70-100 cm a "stone layer" is present with a thickness of 5 to 15 cm, containing few, fine to medium, iron rich angular concretions and few quartz gravels; the layer forms no limitation for root development. Land use: at site nearly permanently cultivated plots of smallholders, nearby large cotton estates.

Classification

WRB 2006

WRB 1998

Luvic- Phaeozem (Calcaric Pachic Clayic Chromic)

Pachi-Luvic- Phaeozem (Calcaric Chromic)

0-50 cm	mollic horizon
30-140 cm	argic horizon
-	calcaric

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Calcari-Luvic Phaeozem

Luvic Phaeozem

0-50 cm	mollic A horizon
30-140 cm	argic B horizon
-	calcareous

0-50 cm	mollic A horizon
30-140 cm	argillic B horizon

Other classification

USDA-SCS (1975)

Argiustoll ustic kaolinitic thermic

More images

Physical characteristics

Particle size distribution

Depth (cm)	Gravel % v/v	very coarse sand % w/w	coarse sand % w/w	medium sand % w/w	fine sand % w/w	very fine sand % w/w	Total sand % w/w	coarse silt % w/w	fine silt % w/w	Total silt % w/w	Clay % w/w
0-15	-	1.8	4.6	7.8	12.4	8.5	35.1	8.4	15.0	23.4	41.4
15-30	-	0.6	2.8	6.4	10.8	7.5	28.1	8.1	15.5	23.6	48.3
30-50	-	0.8	2.3	4.9	9.0	5.2	22.2	7.1	11.2	18.3	59.5
50-82	-	0.8	2.2	2.9	4.6	3.3	13.8	2.6	6.3	8.9	77.3
82-125	-	1.2	3.5	4.3	6.4	4.6	20	4.8	8.1	12.9	67.1
140-160	-	2.4	11.4	13.0	16.9	10.2	53.9	9.1	13.1	22.2	23.9

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
15-21	1.190	-	-	-	-
0-15	-	-	-	16.2	41.4
15-30	-	-	-	19.8	48.3
35-40	1.442	-	-	-	-
75-80	1.467	-	-	-	-
30-50	-	-	-	25.1	59.5
50-82	-	-	-	21.9	77.3
82-125	-	-	-	22.1	67.1
140-160	-	-	-	-	23.9

Other physical data

Depth (cm)	Bulk density kg/dm³	pF 0 % v/v	pF 1.0 % v/v	pF 1.5 % v/v	pF 2.0 % v/v	pF 2.3 % v/v	pF 2.7 % v/v	pF 3.4 % v/v	pF 4.2 % v/v
15-21	1.190	51.9	46.0	36.5	30.8	29.6	28.0	24.6	22.7
35-40	1.442	46.2	45.1	40.4	36.0	35.0	33.7	32.6	31.0
75-80	1.467	47.1	46.4	43.8	39.7	37.7	36.5	40.6	38.2

Chemical data

Depth (cm)	pH H2O	pHKCl	EC 1: 2.5 dS/m	CaCO3 % w/w	C % w/w	N %	C / N	Exch. Acid cmol(c)/kg	Exch. Al cmol(c)/kg	Ca cmol(c)/kg	Mg cmol(c)/kg	K cmol(c)/kg	Na cmol(c)/kg	Sum Cations cmol(c)/kg
0-15	7.1	6.0	0.13	3.1	2.81	0.19	15	-	-	22.5	2.6	1.2	0.2	26.5
15-30	7.9	6.6	0.13	2.3	1.92	0.14	14	-	-	21.9	4.9	0.3	0.2	27.3
30-50	7.9	6.3	0.09	3.0	1.18	0.10	12	-	-	15.2	4.9	0.2	0.1	20.4
50-82	7.8	6.1	0.08	2.0	0.74	0.09	8	-	-	11.5	6.9	0.2	0.3	18.9
82-125	8.0	6.0	0.06	2.7	0.51	0.08	6	-	-	10.7	7.2	0.1	0.2	18.2

Depth (cm)	Base sat. %	CEC soil cmol(c)/kg	CEC clay cmol(c)/kg	CEC org cmol(c)/kg	ECEC cmol(c)/kg	Al sat. %	ESP %
0-15	86	30.9	75	9.8	-	-	1
15-30	97	28.1	58	6.7	-	-	1
30-50	93	21.9	37	4.1	-	-	0
50-82	88	21.5	28	2.6	-	-	1
82-125	96	18.9	28	1.8	-	-	1

Depth (cm)	pH NaF	P Retention %	ODOE	Al o % w/w	Si o % w/w	Fe d % w/w	Al d % w/w	Fe p % w/w	Al p % w/w	C p % w/w	Fe o % w/w
0-15	-	-	-	0.25	0.11	4.42	0.25	0.07	0.18	-	0.20
15-30	-	-	-	0.23	0.09	5.08	0.26	0.03	0.11	-	0.20
30-50	-	-	-	0.21	0.10	5.69	0.35	0.01	0.08	-	0.21
50-82	-	-	-	0.23	0.11	5.67	0.39	0.02	0.08	-	0.23
82-125	-	-	-	0.19	0.09	5.59	0.41	0.02	0.09	-	0.19

Elemental composition of the soil

Depth (cm)	Al2O3 % w/w	CaO % w/w	Fe2O3 % w/w	K2O % w/w	MgO % w/w	Na2O % w/w	SiO2 % w/w	TiO2 % w/w
0-15	20.8	3.61	10.3	0.91	1.96	-	50.3	0.81
15-30	21.5	3.31	11.1	0.75	1.84	-	49.4	0.81
30-50	23.8	2.29	11.5	0.65	1.49	-	47.1	0.85
50-82	27.9	1.37	11.8	0.45	1.11	-	44.8	0.73
82-125	26.9	2.19	12.7	0.33	1.70	-	44.2	0.70

Depth (cm)	Al2O3/Fe2O3 mol/mol	LOI % w/w	MnO2 % w/w	P2O5 % w/w	SiO2 / Al2O3 mol/mol	SiO2/Fe2O3 mol/mol	SiO2 / R mol/mol
0-15	3.2	10.8	0.13	0.11	4.1	13.0	3.1
15-30	3.0	10.1	0.14	0.04	3.9	11.8	2.9
30-50	3.2	12.0	0.12	0.02	3.4	10.9	2.6
50-82	3.7	11.7	0.09	0.01	2.7	10.1	2.1
82-125	3.3	10.8	0.11	0.02	2.8	9.2	2.1

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-15	-	-	-	very weak to weak	-	very weak to weak	strong	-	-	very weak	weak to medium	-
15-30	-	-	-	very weak to weak	-	very weak to weak	strong	-	-	very weak	weak to medium	-
30-50	-	-	-	very weak to weak	-	very weak to weak	strong	-	-	very weak	weak to medium	-
50-82	-	-	-	very weak to weak	-	very weak to weak	very strong	-	-	very weak	weak	-
82-125	-	-	-	very weak to weak	-	very weak to weak	very strong	-	-	very weak	weak	-

Sand mineralogy

Depth (cm)	Heavy Frac. sand % w/w	K-Feldspar % w/w	Light Fra. sand % w/w	Opaque % w/w	Plagioclase % w/w	Quartz % w/w
30-50	-	20	-	21	57	23
82-125	-	18	-	10	63	19

Minerals

Depth (cm)	Anatase % w/w	Andalusite % w/w	Apatite % w/w	Augite % w/w	Biotite % w/w	Hornblende (basaltic) % w/w
30-50	-	-	-	13	-	40
82-125	-	-	-	12	-	42

Depth (cm)	Grenate % w/w	Grossular % w/w	Muscovite % w/w	Rutile % w/w	Sillimanite % w/w	Spinel % w/w
30-50	6	-	-	3	-	-
82-125	2	-	-	-	-	-

Profile description

Ah 0-30 cm	very dark grey (5YR 3/1, moist)clay,moderate very fine and fine subangular blocky and moderate very fine and fine crumb,slightly hard very friable slightly sticky slightly plastic,no cutans,many very fine yo medium pores,many fine and medium roots,moderately calcareous (2-10%),clear smooth boundary to,
30-50 cm	dark reddish brown (2.5YR 3/4, moist)dark reddish brown (5YR 3/2, moist),clay,clay,moderate to strong fine and medium subangular blocky and moderate to strong fine and medium angular blocky,moderate to strong fine and medium subangular blocky and moderate to strong fine and medium angular blocky,hard friable sticky plastic,hard friable sticky plastic,broken thick clay cutans,continuous thick clay cutans,many very fine pores,common very fine and fine pores,common fine roots,common fine roots,few fine and medium gravel quartz fragments,moderately calcareous (2-10%),moderately calcareous (2-10%),gradual smooth boundary to,gradual smooth boundary to,
95-140 cm	(2.5YR 3/5, moist)clay,moderate fine subangular blocky and moderate fine angular blocky,hard friable sticky plastic,continuous thick clay cutans,common fine pores,common fine roots,very few medium gravel strongly weathered rotten rock fragments and few fine gravel fresh fragments,moderately calcareous (2-10%),diffuse wavy boundary to,
140-160 cm	strong brown (7.5YR 5/8, moist)rock structure,(2.5 YR 3/4),strongly weathered rotten rock fragments,moderately calcareous (2-10%),

Depth1	140cm
Kind 1 (parent material) ; Parker (eds), 1984	gabbro
Mode of accumulation or deposition of parent material	residual material
Remarks on Parent Materials	Basement Complex
Soil Depth	140cm
Texture of parent material	clayey
Weathering Resistance	moderate
General characterization of the status of weathering of solid rock	partially or moderately

Intensity of the soil erosion type	moderate
Soil erosion type	rill

Land use or vegetation in the immediate vicinity of the site	low level arable farming
Remarks on Land Use / Vegetation	VEGETATION: Originally probably dense rich forest
Status of vegetation; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	secondary
Major vegetation type; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	grassland

Altitude	180m
Physiographic Unit	dissected interfluve
Physiographic position of the site	crest
Regional landform; McDonald, R.C., Isbell, R.F. et all, 1984; Australian soil and land survey Field Handbook, Inkata Press, Melbourne.	peneplain
Slope	2%
Form of the slope surrounding the site	convex
Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	flat or almost flat

Drainage class ; FAO (2006) - Guidelines for soil description	well
Dry From - To	85-160cm
Flooding frequency (FAO, 1986)	never
Kind of ground water table (USDA, 1979)	no groundwater table observed
Moist From - To	0-85cm
Estimated permeability (class) of least permeable part of the profile	moderate
Estimated run off (class)	very slow

Evidence of alkali ; Soil Survey Manual USDA, 1951	non-alkaline
Surface cracking	small cracks (width less than 1 cm, or depth less than 50 cm)
Slaking of aggregates by tillage, rainfall or frost (USDA/SCS, 1979)	no surface slaking/crusting observed
Micro relief type: small-scale differences in relief in the direct vicinity of the site (FAO, 1986)	termite/ant mounds
Microrelief pattern	isolated
Rock outcrop class (FAO (2006) - Guidelines for soil description)	none
Evidence of salt; Soil Survey Manual USDA, 1951	non-saline
Surface stoniness class (FAO (2006) - Guidelines for soil description)	none

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Reference soil Mozambique 05: Phaeozem

Characteristics

Reference soil MZ005: Phaeozems

Classification