Reference soil Côte d'Ivoire 07: Acrisol

CI007

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 CI007: Acrisols

A very deep (125-180 cm), moderately well drained, strong brown gravelly clay soil. Plinthite starting at 60 cm depth. With high biological activity (termites, ants, earthworms).

Classification

WRB 2006

WRB 1998

Pisoplinthic-Cutanic-Vetic- Acrisol (Hyperdystric Profondic Clayic)

Veti-Pisoplinthic- Acrisol (Hyperdystric)

18-60 cm	pisoplinthic horizon
60-150 cm	plinthic horizon
7-150 cm	argic horizon

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Veti-Plinthic Acrisol skeletic

Plinthic Ferralsol petric

0-7 cm	ochric A horizon
7-150 cm	argic / ferralic B horizon
-	ferric
-	plinthite

0-7 cm	ochric A horizon
7-150 cm	argillic / oxic B horizon
-	ferric
-	plinthite

Local classification:	Sol ferrallitique, see remarks

Other classification

USDA-NRCS (1999)	Acrudoxic Plinthic Kandiudult
USDA-SCS (1975)	Acrudoxic Plinthic Plinthudult udic clayey oxidic isohyperthermic

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
0-7	7	7.0	14.7	17.2	18.5	8.4	65.8	5.2	5.8	11	23.2
7-15	29	12.4	13.4	12.9	14.2	6.6	59.5	5.2	6.8	12	28.7
15-30	63	10.9	8.9	9.4	12.8	6.7	48.7	3.6	8.3	11.9	39.4
40-60	47	12.0	9.6	8.5	9.7	4.8	44.6	3.2	8.6	11.8	43.6
60-85	40	6.5	8.8	7.2	7.6	4.3	34.4	4.4	10.6	15	50.6
90-110	55	7.9	9.1	6.6	6.4	3.7	33.7	4.8	13.4	18.2	48.1
120-150	85	1.4	5.2	5.1	6.1	4.1	21.9	8.2	21.4	29.6	48.4

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
0-7	-	-	-	6.2	23.2
5-10	1.41	-	-	-	-
50-70	1.36	-	-	-	-
7-15	-	-	-	14.1	28.7
15-30	-	-	-	22.3	39.4
40-60	-	-	-	7.0	43.6
60-85	-	-	-	0.5	50.6
90-110	1.30	-	-	0.0	48.1
120-150	-	-	-	0.5	48.4

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
5-10	1.41	45.2	44.1	40.4	36.3	34.8	32.0	14.8	12.9
50-70	1.36	47.1	45.7	41.7	37.9	36.6	34.9	31.3	29.5
90-110	1.30	49.9	49.2	46.1	43.1	41.7	39.8	29.5	26.5

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
0-7	5.4	4.7	0.18	-	1.75	0.13	13	0.1	0.0	3.9	1.1	0.1	0.1	5.2
7-15	5.2	4.3	0.07	-	1.34	0.11	12	0.3	0.0	1.8	0.8	0.0	0.0	2.6
15-30	4.8	3.9	0.03	-	0.97	0.09	11	1.3	0.9	0.0	0.2	0.0	0.1	0.3
40-60	4.7	3.9	0.02	-	0.59	0.05	12	1.2	0.7	0.0	0.1	0.0	0.0	0.1
60-85	4.8	4.0	0.02	-	0.60	0.05	12	1.2	0.7	0.0	0.1	0.0	0.0	0.1
90-110	4.8	4.0	0.02	-	0.46	0.05	9	1.2	0.7	0.0	0.2	0.0	0.0	0.2
120-150	4.9	4.0	0.02	-	0.31	-	-	1.2	0.7	0.0	0.2	0.0	0.1	0.3

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 %
0-7	75	6.9	30	6.1	-	0	1
7-15	49	5.3	18	4.7	-	0	0
15-30	9	3.5	9	3.4	-	26	3
40-60	4	2.6	6	2.1	-	27	0
60-85	4	2.3	5	2.1	-	30	0
90-110	9	2.3	5	1.6	-	30	0
120-150	14	2.1	4	1.1	-	33	5

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
0-7	-	-	-	0.1	0.0	2.1	0.2	-	-	-	0.3
7-15	-	-	-	0.1	0.0	2.2	0.3	-	-	-	0.4
15-30	-	-	-	0.1	0.0	3.2	0.4	-	-	-	0.3
40-60	-	-	-	0.1	0.0	4.8	0.5	-	-	-	0.1
60-85	-	-	-	0.1	0.0	4.1	0.5	-	-	-	0.2
90-110	-	-	-	0.1	0.0	4.8	0.6	-	-	-	0.1
120-150	-	-	-	0.1	0.0	4.2	0.5	-	-	-	0.1

Elemental composition of the clay

Depth (cm)	SiO2 % w/w	Al2O3 % w/w	Fe2O3 % w/w	CaO % w/w	MgO % w/w	K2O % w/w	Na2O % w/w	TiO2 % w/w
0-7	39.6	34.1	10.0	0.08	0.06	0.01	-	1.10
7-15	39.8	34.2	9.9	0.04	0.07	0.01	-	1.09
15-30	39.3	34.3	10.1	0.00	0.05	0.00	-	1.04
40-60	38.4	33.7	10.8	0.00	0.05	0.00	-	1.03
60-85	39.4	34.6	10.8	0.00	0.03	0.00	-	1.02
90-110	39.0	34.0	10.1	0.00	0.03	0.00	-	1.04
120-150	39.6	34.5	10.3	0.00	0.02	0.00	-	-

Depth (cm)	MnO2 % w/w	P2O5 % w/w	Ign.Loss clay % w/w	Total Clay % w/w	SiO2/Al2O3 mol/mol	SiO2/Fe2O3 mol/mol	SiO2 / R mol/mol	Al2O3/Fe2O3 mol/mol
0-7	0.03	0.26	14.2	99.44	2	10.5	1.7	5.3
7-15	0.02	0.20	14.0	99.33	2	10.7	1.7	5.4
15-30	0.01	0.15	14.2	99.15	1.9	10.3	1.6	5.3
40-60	0.01	0.15	14.2	98.34	1.9	9.4	1.6	4.9
60-85	0.01	0.16	14.2	100.22	1.9	9.7	1.6	5
90-110	0.01	0.15	14.3	98.63	1.9	10.3	1.6	5.3
120-150	0.01	0.15	14.5	99.08	1.9	10.2	1.6	5.2

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
0-7	8.3	0.10	4.0	0.02	0.07	-	79.8	0.51
7-15	15.1	0.00	7.0	0.00	0.04	-	67.7	0.75
15-30	11.1	0.04	5.5	0.01	0.06	-	74.7	0.62
40-60	17.7	0.00	8.3	0.00	0.06	-	64.3	0.80
60-85	20.6	0.00	8.0	0.00	0.03	-	61.9	0.83
90-110	22.4	0.00	8.2	0.00	0.05	-	58.6	0.90
120-150	24.4	0.00	8.4	0.00	0.03	-	55.4	0.92

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
0-7	3.3	6.9	0.02	0.02	16.3	53	12.5
7-15	3.4	8.1	0.01	0.01	7.6	25.7	5.9
15-30	3.2	7.4	0.02	0.01	11.4	36.2	8.7
40-60	3.3	8.4	0.01	0.01	6.2	20.6	4.7
60-85	4	9.4	0.01	0.01	5.1	20.6	4.1
90-110	4.3	9.8	0.01	0.01	4.4	19	3.6
120-150	4.5	10.3	0.01	0.01	3.9	17.5	3.2

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-7	very weak to weak	-	very weak to weak	weak to medium	-	-	very strong	-	-	-	-	weak
7-15	weak	-	very weak to weak	weak to medium	-	-	very strong	-	-	-	-	very weak to weak
15-30	weak	-	very weak to weak	weak to medium	-	-	very strong	-	-	-	-	very weak
40-60	weak to medium	-	very weak to weak	weak to medium	-	-	very strong	-	-	-	-	-
60-85	weak to medium	-	very weak to weak	weak to medium	-	-	very strong	-	-	-	-	-
90-110	weak to medium	-	very weak to weak	weak to medium	-	-	very strong	-	-	-	-	-
120-150	weak	-	very weak to weak	weak to medium	-	-	very strong	-	-	-	-	-

Profile description

Ah 0-7 cm	(dark) brown (10YR 4/3, moist)sandy clay loam,moderate fine subangular blocky,friable sticky plastic,many very fine medium interstitial pores and many medium tubular pores,many very fine to coarse roots,non calcareous,clear smooth boundary to,
BA 7-18 cm	yellowish brown (10YR 5/8, moist)gravelly sandy clay loam,moderate fine subangular blocky,friable sticky plastic,patchy cutans on rock fragments,common very fine to medium interstitial pores and common very fine to medium tubular pores,many very fine to coarse roots,very few medium spherical hard ferruginous nodules,very few fine gravel quartz and medium gravel quartz fragments,non calcareous,clear wavy boundary to,
Boc1 18-35 cm	strong brown (7.5YR 5/8, moist)very gravelly clay,moderate fine subangular blocky,friable sticky plastic,broken thin clay and sesquioxide cutans on rock fragments,common very fine and fine interstitial pores and common very fine and fine tubular pores,common very fine and fine roots,very frequent medium spherical hard ferruginous nodules and few charcoal fragments,very few fine gravel quartz fragments,non calcareous,clear irregular boundary to,
Boc2 35-60 cm	strong brown (7.5YR 5/8, moist)gravelly clay,moderate fine angular blocky to subangular blocky,friable sticky plastic,broken thin clay and sesquioxide cutans,common very fine and fine tubular pores and common very fine and fine interstitial pores,few very fine and fine roots,frequent medium irregular hard charcoal nodules and very frequent medium irregular hard argillaceous nodules,non calcareous,gradual smooth boundary to,
Bv1 60-85 cm	yellowish brown (10YR 5/8, moist)slightly gravelly clay,moderate very fine and fine angular blocky to subangular blocky,friable sticky plastic,many (15-40%) mottles (5YR 5/8),broken thin clay and sesquioxide cutans on pedfaces,few to common very fine tubular pores and few to common very fine interstitial pores,few very fine and fine roots,very frequent medium irregular soft ferruginous nodules,non calcareous,gradual smooth boundary to,
Bv2 85-150 cm	strong brown (7.5YR 5/8, moist)clay,moderate very fine and fine angular blocky to subangular blocky,friable sticky plastic,common (5-15%) medium faint diffuse mottles (10 YR 5/6) and many (15-40%) coarse prominent clear mottles (2.5 YR 4/6),broken thin clay and sesquioxide cutans on pedfaces,many very fine and fine tubular pores and many very fine and fine interstitial pores,few very fine and fine roots,very frequent large irregular soft argillaceous nodules ferruginous nodules,few quartz fragments,non calcareous,

Kind 1 (parent material) ; Parker (eds), 1984	metamorphic rock
Mode of accumulation or deposition of parent material	residual material
Remarks on Parent Materials	Precambrian migmatite
Texture of parent material	clayey
Weathering Resistance	moderate
General characterization of the status of weathering of solid rock	highly

Land use or vegetation in the immediate vicinity of the site	nature and game preservation
Remarks on Land Use / Vegetation	VEGETATION: Tropical lowland forest; national park; logged once
Status of vegetation; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	primary
Major vegetation type; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	evergreen forest

Altitude	165m
Physiographic Unit	dissected peneplain
Physiographic position of the site	middle slope
Regional landform; McDonald, R.C., Isbell, R.F. et all, 1984; Australian soil and land survey Field Handbook, Inkata Press, Melbourne.	peneplain
Slope	3%
Slope Aspect	east
Form of the slope surrounding the site	convex
Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	rolling

Drainage class ; FAO (2006) - Guidelines for soil description	moderately well
Flooding frequency (FAO, 1986)	never
Kind of ground water table (USDA, 1979)	no groundwater table observed
Moist From - To	0-150cm
Estimated permeability (class) of least permeable part of the profile	high
Estimated run off (class)	medium

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
Microrelief Height: variation in height	100
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 Côte d'Ivoire 07: Acrisol

Characteristics

Reference soil CI007: Acrisols

Classification