Reference soil Ecuador 11: Phaeozem

EC011

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 EC011: Phaeozems

EC11 is comparable to profile Ecuador No.13 in: part III tourguide for Ecuador of the sixth international soil classification workshop (1984). The soil has been redescribed and resampled by G.del Posso in May 1987, additionally two monoliths has been taken. The A2 horizon includes also 7.5 YR 3/4 colour. The 2Btbe is multicoloured having 10YR44, 2.5YR4/8 and 5Y6/2 colours. The coatings on peds from 55cm and deeper includes also some pressure cutans. In the surroundings of the site also maize and soybeans.

Classification

WRB 2006

WRB 1998

Luvic-Vitric- Phaeozem

Luvi-Vitric- Phaeozem

0-30 cm	mollic horizon
30-165 cm	argic horizon
-	vitric

0-30 cm	mollic horizon
0-77 cm	vitric horizon
30-165 cm	argic horizon

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Andi-Luvic Phaeozem

Luvic Phaeozem

0-30 cm	mollic A horizon
30-165 cm	argic B horizon
-	andic
-	strongly humic

0-30 cm	mollic A horizon
30-165 cm	argillic B horizon
-	smeary consistence

Local classification:	Suelos de chocolate

Other classification

USDA-SCS (1975)

Paleustoll ustic medial over clayey mixed 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
0-30	0	0.1	0.1	0.2	6.9	15.6	22.9	19.0	32.7	51.7	25.3
30-55	0	0.1	0.1	0.2	8.2	14.9	23.5	16.2	26.7	42.9	33.6
55-77	0	0.4	0.3	0.5	8.3	13.7	23.2	15.9	30.1	46.0	30.9
77-107	0	0.3	0.4	0.5	2.4	3.4	7.0	7.1	15.4	22.5	70.5
107-165	0	0.0	0.1	0.1	0.7	1.1	2.0	3.2	11.1	14.3	83.6

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
0-30	-	-	-	2.0	25.3
25-40	0.990	-	-	-	-
30-55	-	-	-	13.1	33.6
55-70	1.340	-	-	-	-
55-77	-	-	-	15.2	30.9
80-110	1.090	-	-	-	-
77-107	-	-	-	14.8	70.5
107-165	-	-	-	17.9	83.6

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
25-40	0.990	58.0	57.0	47.7	41.1	39.1	37.5	26.2	23.3
55-70	1.340	48.0	47.7	44.3	42.0	40.9	39.9	31.1	27.3
80-110	1.090	59.6	59.5	57.9	56.6	56.1	55.5	49.0	45.7

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
0-30	5.4	4.5	0.21	-	2.79	0.30	9	-	-	9.9	1.0	1.5	0.2	12.6
30-55	6.8	5.2	0.05	0.9	1.47	0.13	11	-	-	14.5	1.1	1.8	0.2	17.6
55-77	6.9	5.2	0.05	0.8	0.64	0.06	11	-	-	8.9	0.8	1.4	0.2	11.3
77-107	6.7	5.4	0.12	0.7	0.34	0.06	6	-	-	9.0	1.7	1.8	0.2	12.7
107-165	6.7	5.4	0.12	0.7	0.28	0.04	7	-	-	8.6	2.1	1.9	0.3	12.9

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 %
0-30	55	23.1	91	9.8	-	-	1
30-55	84	21.0	63	5.3	-	-	1
55-77	84	13.4	43	2.1	-	-	1
77-107	88	14.4	20	1.1	-	-	1
107-165	85	15.2	18	1.1	-	-	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
0-30	8.8	51	-	0.80	0.30	1.70	0.30	0.30	0.30	-	1.00
30-55	8.5	38	-	0.50	0.30	2.20	0.30	0.10	0.10	-	1.00
55-77	8.3	27	-	0.30	0.20	2.30	0.20	0.00	0.00	-	0.70
77-107	8.7	35	-	0.20	0.10	3.70	0.40	0.00	0.00	-	0.30
107-165	8.7	39	-	0.20	0.10	4.50	0.40	0.00	0.00	-	0.20

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-30	-	weak	-	-	medium to strong	-	-	-	-	-	-	-
30-55	-	weak	-	-	medium to strong	-	-	-	-	-	-	-
55-77	-	medium to strong	-	-	medium to strong	-	-	-	-	-	-	-
77-107	-	weak	-	-	medium to strong	-	-	-	-	-	-	-
107-165	-	weak	-	-	medium to strong	-	-	-	-	-	-	-

Profile description

Ah1 0-30 cm	black (10YR 2/1, moist)loam,moderate medium and coarse subangular blocky,very friable non sticky non plastic weakly smeary,many very fine tubular pores and common medium tubular pores,gradual wavy boundary to,
Ah2 30-55 cm	very dark brown (10YR 2/2, moist)silt loam,moderate fine and medium subangular blocky,very friable slightly sticky slightly plastic weakly smeary,many very fine medium tubular pores and few tubular pores,diffuse wavy boundary to,
Bt 55-77 cm	very dark brown (10YR 2/2, moist)silty clay,strong medium and coarse subangular blocky,friable slightly sticky slightly plastic,patchy thin clay on pedfaces cutans,many very fine fine tubular pores,diffuse wavy boundary to,
2Btb1 77-107 cm	dark brown (7.5YR 3/4, moist)clay,moderate coarse prismatic parting to moderate coarse angular blocky,firm sticky plastic,continuous thin clay on pedfaces cutans,common very fine fine tubular pores and few tubular pores,gradual wavy boundary to,
2Btb2 107-165 cm	claymoderate coarse and very coarse prismatic parting to moderate medium and coarse angular blocky,firm sticky plastic,continuous thin clay on pedfaces cutans,common very fine fine tubular pores,

Depth1	77cm
Kind 1 (parent material) ; Parker (eds), 1984	pyroclastic, unconsolidated
Kind 2 (parent material) (second entry); Parker (eds), 1984	pyroclastic, unconsolidated
Mode of accumulation or deposition of parent material	ejecta ash
Mode of accumulation or deposition of parent material (second entry)	ejecta ash
Remarks on Parent Materials	multiple ash layers
Soil Depth	165cm
Texture of parent material	loamy
Texture of parent material (second entry)	clayey
Weathering Resistance	poor
Weathering Resistance (second entry)	poor
General characterization of the status of weathering of solid rock	slightly
General characterization of the status of weathering of solid rock (second entry)	partially or moderately

Major crops	cocoa
Land use or vegetation in the immediate vicinity of the site	medium level arable farming
Remarks on Land Use / Vegetation	VEGETATION: Forest with guajaba, cocoa and coffee LANDUSE: Nearby maize and soybean
Major vegetation type; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	semi-deciduous forest

Altitude	100m
Physiographic Unit	higher part of fan
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.	alluvial plain
Slope	1%
Form of the slope surrounding the site	straight
Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	flat or almost flat

Drainage class ; FAO (2006) - Guidelines for soil description	moderately well
Depth to groundwater table	900cm
Kind of ground water table (USDA, 1979)	groundwater table observed
Moist From - To	0-200cm
Estimated permeability (class) of least permeable part of the profile	moderate
Estimated run off (class)	slow

Evidence of alkali ; Soil Survey Manual USDA, 1951	non-alkaline
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 Ecuador 11: Phaeozem

Characteristics

Reference soil EC011: Phaeozems

Classification