Reference soil Kenya 69: Phaeozem

KE069

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 KE069: Phaeozems

Slides: 10,229 - 10,233.

Classification

WRB 2006

WRB 1998

Petrocalcic-Rendzic- Phaeozem

Epipetric- Calcisol

0-28 cm	mollic horizon
28-45 cm	petrocalcic horizon
-	calcaric
-	secondary carbonates

FAO-UNESCO-ISRIC 1988

Petrocalci-Rendzic Leptosol

0-28 cm	mollic A horizon
28-45 cm	petrocalcic horizon

Other classification

USDA-NRCS (1999)	Lithic Haplustoll
USDA-SCS (1975)	Lithic Rendoll ustic isothermic

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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
0-24	0	6.6	9.7	14.5	19.3	4.9	55	7.8	5.5	13.3	31.7
24-30	5	11.2	10.3	12.2	13.6	5.5	52.8	6.0	10.0	16	31.3

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
0-24	-	-	-	8.0	31.7
24-30	-	-	-	8.5	31.3

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
0-24	7.3	6.2	0.14	1.5	2.02	0.14	14	-	-	25.2	1.7	0.5	0.1	27.5
24-30	8.0	7.2	0.16	9.6	2.12	0.13	16	-	-	44.4	1.4	0.4	0.1	46.3

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 %
0-24	107	25.7	62	7.1	-	-	0
24-30	160	28.9	80	7.4	-	-	0

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-24	-	-	-	very weak	-	-	medium to strong	weak	-	-	weak	-

Profile description

Ah 0-24 cm	black (10YR 2/1, moist)clay loam,moderate medium subangular blocky parting to crumb,soft very friable slightly sticky slightly plastic,many very fine pores and few fine and medium pores,many very fine and few fine roots,frequent fine gravel weathered limestone frequent medium gravel weathered fragments,slightly calcareous (0-2%),clear smooth boundary to,
AC 24-30 cm	dark brown (7.5YR 3/2, moist)gravelly sandy clay,moderate medium subangular blocky parting to crumb,soft very friable slightly sticky slightly plastic,many very fine pores and few fine pores,many very fine and few fine roots,common medium and coarse gravel weathered limestone,moderately calcareous (2-10%),abrupt irregular boundary to,
Ckm 30-70 cm	many coarse gravel and stones weathered limestone and many fine gravel weathered fragmentscontinuous platy indurated petrocalcic pans,extremely calcareous (>25%),

Kind 1 (parent material) ; Parker (eds), 1984	limestone
Mode of accumulation or deposition of parent material	residual material
Remarks on Parent Materials	crystaline limestone and quartz-biotite gneiss of Basement System
Soil Depth	30cm
Texture of parent material	loamy
Texture of parent material (second entry)	gravelly
Weathering Resistance	high
General characterization of the status of weathering of solid rock	partially or moderately

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

Land use or vegetation in the immediate vicinity of the site	woodland, grazed
Remarks on Land Use / Vegetation	VEGETATION: Bushed grassland of Acacia mellifera and Acacia thomasii wih Sporobolus and Eragrostis species. LAND USE: Militairy trainingground
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 woodland

Altitude	1745m
Physiographic Unit	footslope of hills
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.	hill
Slope	6%
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	well
Flooding frequency (FAO, 1986)	never
Kind of ground water table (USDA, 1979)	no groundwater table observed
Moist From - To	0-70cm
Estimated permeability (class) of least permeable part of the profile	moderate
Estimated run off (class)	rapid
Drainage class - intergrade; FAO (2006) - Guidelines for soil description	somewhat excessive

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)	surface partly slaked, round smooth aggregates
Microrelief Height: variation in height	15
Micro relief type: small-scale differences in relief in the direct vicinity of the site (FAO, 1986)	terracettes
Microrelief pattern	isolated
Rock outcrop class (FAO (2006) - Guidelines for soil description)	very rocky
Evidence of salt; Soil Survey Manual USDA, 1951	non-saline
Shape of stones (on average)	platy or flat
Surface stoniness class (FAO (2006) - Guidelines for soil description)	exceedingly stony

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Reference soil Kenya 69: Phaeozem

Characteristics

Reference soil KE069: Phaeozems

Classification