Reference soil Mozambique 04: Acrisol

MZ004

Acrisols occur dominantly in the wetter parts of the tropics and subtropics and the warm temperate regions in relatively young landscapes.

Characteristics

Soils having an argic horizon (a subsurface horizon with distinct higher clay content than the overlying horizon), which has a cation exchange capacity of less than 24 cmolc per kg in some part, either starting within 100 cm from the soil surface, or within 200 cm from the soil surface if the argic horizon is overlain by loamy sand or coarser textures throughout. They have a base saturation (total amount of Ca, Mg, K and Na with respect to the cation exchange capacity) of less than 50 percent in the major part between 25 and 100 cm from the soil surface

Distribution of Acrisols (rough estimation supplied by soilgrids)

Reference soil MZ004: Acrisols

Short description of the profile: a very deep, well drained, dusky red clay soil, weakly to moderately structured up to 125 cm, than porous massive; a dark coloured topsoil. Vegetation: closed bambu forest with scattered high trees. Nearby permanent , mechanized farming with maize and cotton as crops. At the surface an about 1 cm thick layer of litter. The upper horizon has a few holes filled with reddish subsoil the subsoil has a few holes filled with dark coloured topsoil. Traces of magnetite are present from 30 cm and deeper. Spherical termite holes with a flat bottom and with a diameter of 4 to 8 cm are visible throughout the profile, the density is about 4 per square meter.

Classification

WRB 2006

WRB 1998

Umbric-Cutanic- Acrisol (Clayic Rhodic)

Rhodi-Umbric- Acrisol

0-30 cm	umbric horizon
125-175 cm	ferralic horizon
18-125 cm	argic horizon

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Umbri-Haplic Acrisol

Humic Acrisol

0-30 cm	umbric A horizon
125-175 cm	ferralic B horizon
18-125 cm	argic B horizon

0-30 cm	umbric A horizon
125-175 cm	oxic B horizon
18-125 cm	argillic B horizon

Local classification:	Ithaya Yoquilla

Other classification

USDA-SCS (1975)

Paleustalf ustic kaolinitic isohyperthermic

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
0-5	-	1.7	8.1	16.9	24.3	11.6	62.6	7.3	8.3	15.6	21.9
5-18	-	2.2	8.6	16.1	22.0	11.3	60.2	6.0	6.9	12.9	26.7
18-28	-	2.2	8.9	13.6	17.9	8.7	51.3	6.1	3.3	9.4	39.4
30-50	-	3.0	7.5	9.7	12.9	6.7	39.8	4.1	11.0	15.1	55.1
60-90	-	2.3	5.4	7.8	10.7	5.4	31.6	3.4	2.2	5.6	62.7
125-170	-	2.2	5.1	7.7	12.1	6.7	33.8	4.4	2.6	7	59.2
225-275	-	3.1	4.3	6.8	11.4	7.2	32.8	5.5	5.0	10.5	56.8

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
0-5	-	-	-	7	21.9
15-20	1.399	-	-	-	-
45-50	1.448	-	-	-	-
5-18	-	-	-	9.5	26.7
18-28	-	-	-	14.4	39.4
130-135	1.240	-	-	-	-
30-50	-	-	-	15.2	55.1
60-90	-	-	-	10.2	62.7
125-170	-	-	-	0.5	59.2
225-275	-	-	-	0.0	56.8

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
15-20	1.399	42.9	38.6	32.0	26.4	24.9	23.3	21.9	20.6
45-50	1.448	42.3	41.6	36.6	32.4	30.9	29.4	25.4	24.6
130-135	1.240	49.5	48.1	39.5	31.2	27.9	25.3	25.2	24.5

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
0-5	5.9	5.3	0.06	-	2.29	0.13	18	0.0	0.0	4.7	4.2	0.1	0.3	9.3
5-18	5.7	4.8	0.03	-	1.77	0.10	18	0.0	0.0	3.3	2.8	0.1	0.1	6.3
18-28	5.6	4.7	0.03	-	1.10	0.07	16	0.1	0.0	2.4	2.0	0.1	0.1	4.6
30-50	5.5	4.5	0.02	-	0.73	0.07	10	0.1	0.0	1.9	1.7	0.1	0.1	3.8
60-90	5.9	4.9	0.01	-	0.42	0.04	11	0.0	0.0	2.1	1.5	0.1	0.1	3.8
125-170	6.4	5.5	0.01	-	0.00	0.05	0	0.0	0.0	2.1	1.7	0.1	0.1	4
225-275	6.4	5.6	0.02	-	0.00	0.03	0	0.0	0.0	2.5	1.8	0.1	0.1	4.5

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 %
0-5	58	15.9	73	8.0	-	0	2
5-18	49	12.9	48	6.2	-	0	1
18-28	47	9.7	25	3.9	-	0	1
30-50	42	9.1	17	2.6	-	0	1
60-90	46	8.2	13	1.5	-	0	1
125-170	56	7.2	12	0.0	-	0	1
225-275	61	7.4	13	0.0	-	0	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
0-5	-	-	-	0.08	0.03	2.73	0.13	0.02	0.03	-	0.08
5-18	-	-	-	0.09	0.04	3.14	0.16	0.07	0.05	-	0.10
18-28	-	-	-	0.1	0.06	4.24	0.19	0.07	0.06	-	0.14
30-50	-	-	-	0.11	0.06	5.42	0.25	0.05	0.10	-	0.16
60-90	-	-	-	0.11	0.05	5.98	0.27	0.01	0.05	-	0.16
125-170	-	-	-	0.11	0.04	6.27	0.28	0.00	0.03	-	0.17
225-275	-	-	-	0.09	0.05	6.44	0.03	0.00	0.03	-	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
0-5	7.1	0.27	7.0	0.05	0.16	-	76.8	2.74
5-18	8.8	0.20	7.7	0.03	0.16	-	75.4	2.67
18-28	12.2	0.14	8.8	0.02	0.09	-	69.9	2.29
30-50	16.6	0.10	10.2	0.02	0.10	-	63.5	1.77
60-90	19.9	0.08	11.4	0.02	0.09	-	59.4	1.69
125-170	18.3	0.08	11.3	0.02	0.07	-	59.2	1.88
225-275	19.3	0.09	11.9	0.02	0.09	-	60.1	1.84

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
0-5	1.6	6.3	0.13	0.03	18.4	29.2	11.3
5-18	1.8	6.1	0.12	0.03	14.5	26	9.3
18-28	2.2	6.6	0.11	0.03	9.7	21.1	6.7
30-50	2.5	7.5	0.09	0.03	6.5	16.5	4.7
60-90	2.7	8.3	0.08	0.03	5.1	13.9	3.7
125-170	2.5	7.5	0.10	0.02	5.5	13.9	3.9
225-275	2.5	7.6	0.11	0.01	5.3	13.4	3.8

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-5	-	-	-	weak	-	weak	very strong	-	-	very weak	-	-
5-18	-	-	-	weak	-	weak	very strong	-	-	very weak	-	-
18-28	-	-	-	weak	-	weak	very strong	-	-	very weak	-	-
30-50	-	-	-	weak	-	weak	very strong	-	-	very weak	-	-
60-90	-	-	-	weak	-	weak	very strong	-	-	very weak	-	-
125-170	-	-	-	weak	-	weak	very strong	-	-	very weak	-	-
225-275	-	-	-	weak	-	weak	very strong	-	-	very 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	-	-	-	97	-	100
125-170	-	-	-	96	-	100

Minerals

Depth (cm)	Anatase % w/w	Andalusite % w/w	Apatite % w/w	Augite % w/w	Biotite % w/w	Hornblende (basaltic) % w/w
30-50	-	-	1	-	-	1
125-170	-	-	2	-	-	6

Depth (cm)	Grenate % w/w	Grossular % w/w	Muscovite % w/w	Rutile % w/w	Sillimanite % w/w	Spinel % w/w
30-50	1	-	-	33	4	-
125-170	1	-	-	32	5	-

Profile description

Ah 0-18 cm	dark reddish brown (5YR 2.5/2, moist)sandy clay loam,weak very fine and fine crumb,very friable non sticky slightly plastic,no cutans,many very fine to medium pores,many fine and medium roots,termite channels,non calcareous,clear smooth boundary to,
18-30 cm	dusky red (2.5YR 3/2, moist)sandy clay,weak very fine and fine subangular blocky,very friable slightly sticky slightly plastic,no cutans,many very fine to medium pores,many fine and medium roots,termite channels,non calcareous,gradual smooth boundary to,
Bt1 30-60 cm	dusky red (10R 3/4, moist)clay,weak to moderate very fine and fine subangular blocky,hard very friable slightly sticky slightly plastic,broken moderately thick clay cutans,many very fine to medium pores,many fine roots,termite channels,non calcareous,diffuse smooth boundary to,
Bt2 60-125 cm	(10R 3/5, moist)clay,weak very fine and fine subangular blocky,slightly hard very friable slightly sticky slightly plastic,patchy thin clay cutans,many very fine to medium pores,common fine and medium roots,termite channels,non calcareous,diffuse smooth boundary to,
Bo 125-175 cm	(10R 3/5, moist)clay,porous massive,slightly hard very friable slightly sticky slightly plastic,patchy thin clay cutans,many very fine pores,common fine and medium roots,very few medium soft argillaceous nodules,termite channels,non calcareous,
Auger 175-320 cm	(10R 3/5, moist)clay,non calcareous,
Auger 320-400 cm	(10R 3/5, moist)clay,few medium spherical soft and hard ferruginous concretions,non calcareous,
Auger 400-430 cm	clayfrequent medium spherical soft and hard ferruginous concretions,non calcareous,abrupt boundary to,
R 430-430 cm	dominant coarse gravel and stones hard rock fragmentsnon calcareous,

Depth1	430cm
Kind 1 (parent material) ; Parker (eds), 1984	gabbro
Mode of accumulation or deposition of parent material	residual material
Remarks on Parent Materials	Basement Complex. prob. gabbro norite
Soil Depth	400cm
Texture of parent material	clayey
Weathering Resistance	moderate
General characterization of the status of weathering of solid rock	highly

Intensity of the soil erosion type	slight
Soil erosion type	sheet

Main type of irrigation; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	no irrigation
Land use or vegetation in the immediate vicinity of the site	afforestation
Remarks on Land Use / Vegetation	VEGETATION: Closed bambu forest (see gen. remarks)
Rotation scheme ; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	crop rotation scheme not relevant
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)	closed forest

Altitude	500m
Physiographic Unit	very broad, smooth, interfluve
Physiographic position of the site	upper slope
Regional landform; McDonald, R.C., Isbell, R.F. et all, 1984; Australian soil and land survey Field Handbook, Inkata Press, Melbourne.	peneplain
Slope	1%
Form of the slope surrounding the site	straight
Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	undulating

Drainage class ; FAO (2006) - Guidelines for soil description	well
Dry From - To	25-300cm
Flooding frequency (FAO, 1986)	never
Kind of ground water table (USDA, 1979)	no groundwater table observed
Moist From - To	0-25cm
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	no cracks observed
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

You are here

Reference soil Mozambique 04: Acrisol

Characteristics

Reference soil MZ004: Acrisols

Classification