Reference soil Kenya 52: Cambisol

KE052

Cambisols occur mainly in the temperate and boreal regions of the world, where the soil’s parent material is still young or where low temperatures slow down the processes of soil formation.

Characteristics

Soils having either a cambic horizon (a horizon showing evidence of alteration with respect to the underlying material), or a mollic horizon overlying a subsoil, which has a base saturation of less than 50 percent in some part within 100 cm from the soil surface, or one of the following diagnostic horizons within the specified depth: an andic, vertic, or vitric horizon starting between 25 and 100 cm; a (petro-)plinthic or salic horizon starting between 50 and 100 cm, in absence of loamy sand or coarser textures above these horizons.

Distribution of Cambisols (rough estimation supplied by soilgrids)

Reference soil KE052: Cambisols

Dense bushed woodland with Boscia sp. and Acacia tortillis. Small scale rainfed annual crops, pigeon peas, cotton, millet. Ca-concretions form a surface gravel mulch. Slides: 10,114 - 10,118.

Classification

WRB 2006

WRB 1998

Haplic- Cambisol (Calcaric)

Calcaric- Cambisol

25-150 cm	cambic horizon
-	calcaric
-	secondary carbonates

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Rhodi-Calcaric Cambisol rudic

Calcic Cambisol

0-25 cm	ochric A horizon
25-150 cm	cambic B horizon
-	calcareous

0-25 cm	ochric A horizon
25-150 cm	cambic B horizon
-	soft powdery lime

Other classification

USDA-SCS (1975)

Haplustalf ustic fine-loamy over clayey 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
0-25	-	2.3	7.7	10.0	8.6	4.7	33.3	7.2	16.9	24.1	42.6
25-70	-	2.2	10.0	12.5	11.0	6.3	42	12.0	24.8	36.8	21.3
70-110	-	2.4	9.5	12.5	11.3	7.7	43.4	13.2	25.1	38.3	18.3
110-150	-	3.7	10.6	12.9	11.0	5.3	43.5	10.1	26.3	36.4	20.1

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
0-25	-	-	-	13.5	42.6
25-70	-	-	-	8.6	21.3
70-110	-	-	-	7.2	18.3
110-150	-	-	-	-	20.1

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
0-25	8.2	6.7	0.23	8.5	0.39	0.06	7	-	-	52.8	5.3	0.4	0.0	58.5
25-70	8.3	6.8	0.24	5.6	0.15	0.04	4	-	-	43.4	8.8	0.4	0.1	52.7
70-110	8.3	6.9	0.28	3.5	0.05	0.03	2	-	-	29.7	12.5	0.4	0.2	42.8
110-150	8.4	7.0	0.27	3.1	0.07	0.03	2	-	-	29.1	17.5	0.4	0.4	47.4

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 %
0-25	227	25.8	61	1.4	-	-	0
25-70	238	22.1	104	0.5	-	-	0
70-110	228	18.8	103	0.2	-	-	1
110-150	213	22.3	111	0.2	-	-	2

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
0-25	-	-	-	0.1	0.1	1.7	0.1	-	-	-	0.2
25-70	-	-	-	0.1	0.0	1.5	0.1	-	-	-	0.1
70-110	-	-	-	0.1	0.0	1.4	0.1	-	-	-	0.1
110-150	-	-	-	0.1	0.0	1.4	0.1	-	-	-	0.0

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-25	-	-	-	-	-	-	medium	-	medium	-	medium	-
25-70	-	-	-	-	-	-	weak to medium	-	weak to medium	-	medium to strong	-
70-110	-	-	-	-	-	-	weak to medium	-	weak to medium	-	medium to strong	-
110-150	-	-	-	-	-	-	weak to medium	-	weak to medium	-	strong	-

Profile description

Abk 0-25 cm	dark yellowish brown (10YR 4/4, dry) dark yellowish brown (10YR 4/4, moist)silty clay loam,moderate medium subangular blocky,slightly hard very friable slightly sticky slightly plastic,continuous thin clay cutans throughout,many very fine pores and few fine pores,common very fine and few fine roots,frequent medium irregular hard calcareous concretions,Garnets,Quartz fragments,moderately calcareous (2-10%),clear smooth boundary to,
Bk 25-150 cm	yellowish brown (10YR 5/6, dry) light yellowish brown (10YR 6/4, moist)silty clay loam,moderate very coarse angular blocky,hard very friable slightly sticky slightly plastic,many very fine pores and few fine and medium pores,few very fine roots,few medium and large irregular hard calcareous concretions,Garnets, Quartz fragments,moderately calcareous (2-10%),abrupt irregular boundary to,
150-150 cm	rock structuredominant strongly weathered gneiss fragments,non calcareous,

Depth1	150cm
Kind 1 (parent material) ; Parker (eds), 1984	gneiss
Mode of accumulation or deposition of parent material	residual material
Remarks on Parent Materials	Basement system, hornblende-biotite gneiss
Soil Depth	150cm
Texture of parent material	loamy
Weathering Resistance	moderate
General characterization of the status of weathering of solid rock	partially or moderately

Occurrence of soil aggradation (McDonald et al., 1984)	absent
Intensity of the soil erosion type	severe
Intensity of the soil erosion type (second entry)	moderate
Soil erosion type	sheet
Soil erosion type (second entry)	rill
Slope stability	stable

Major crops	millet
Land improvements ; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	no land improvement
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	fallow
Remarks on Land Use / Vegetation	VEGETATION: Dense bushed woodland with Boscia sp. and Acacia tortillis. LAND USE: Small scale rainfed annual crops, also pigeon peas and cotton
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)	degraded
Major vegetation type; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	deciduous shrub

Altitude	845m
Physiographic Unit	gently und. upland near stream
Physiographic position of the site	lower slope
Regional landform; McDonald, R.C., Isbell, R.F. et all, 1984; Australian soil and land survey Field Handbook, Inkata Press, Melbourne.	plain
Slope	3%
Form of the slope surrounding the site	convex
Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	undulating

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

Evidence of alkali ; Soil Survey Manual USDA, 1951	non-alkaline
Average size of stone	0.5
Surface cracking	no cracks observed
Slaking of aggregates by tillage, rainfall or frost (USDA/SCS, 1979)	no surface slaking/crusting observed
Microrelief pattern	none
Rock outcrop class (FAO (2006) - Guidelines for soil description)	none
Evidence of salt; Soil Survey Manual USDA, 1951	non-saline
Shape of stones (on average)	(sub-)rounded
Surface stoniness class (FAO (2006) - Guidelines for soil description)	exceedingly stony

You are here

Reference soil Kenya 52: Cambisol

Characteristics

Reference soil KE052: Cambisols

Classification