Reference soil Ecuador 09: Andosol

EC009

Andosols occur throughout the world where volcanic activity is common, especially in the circum-Pacific region and along the mid-Atlantic Ridge.

Characteristics

Soils with a vitric or andic horizon (slightly to moderately weathered horizons in pyroclastic deposits dominated by short-range-order minerals, notably allophane and imogolite) starting within 25 cm from the soil surface. In addition, they may have a histic, fulvic, melanic, mollic, umbric, ochric, duric, or cambic horizon. Other diagnostic horizons (unless buried deeper than 50 cm by volcanic deposits) are absent.

Distribution of Andosols (rough estimation supplied by soilgrids)

Reference soil EC009: Andosols

EC02 is comparable to profile Ecuador No.5 in: part III-tourguide for Ecuador of the sixth international soil classification workshop (1984). The soil was redescribed and resampled by G.del Posso in May 1987, additionally two soil monoliths were taken. Down to a depth of 110cm medium and coarse decayed roots are present. The A horizon includes also the 10YR2/1 colour. About 1% fragments of brick and artifacts are present in the first half metre. Twenty years ago the area was frequently flooded by the rio Blanco (and rio Quininde), now the area is protected against flooding.

Classification

WRB 2006

WRB 1998

Umbric-Silandic-Epivitric- Andosol (Dystric Siltic)

Sili-Vitric- Andosol (Umbric Vetic)

56-94 cm	umbric horizon
7-56 cm	cambic horizon
-	vitric
-	andic

0-7 cm	ochric horizon
56-94 cm	andic horizon
56-94 cm	umbric horizon
7-56 cm	vitric horizon

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Dystri-Vitric Andosol

Ochric Andosol

0-7 cm	ochric A horizon
56-94 cm	umbric A horizon
7-56 cm	cambic B horizon
-	andic
-	strongly humic

0-7 cm	ochric A horizon
56-94 cm	umbric A horizon
7-56 cm	cambic B horizon
-	exchange complex dominated by amorphous material

Local classification:	Suelo Mojado

Other classification

USDA-SCS (1975)

Dystrandept udic medial 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	0	0.0	0.1	0.4	16.2	14.3	31.0	16.7	35.9	52.6	16.4
7-24	0	0.1	0.1	0.4	16.1	14.0	30.7	15.1	38.3	53.4	16.0
24-56	0	0.1	0.2	0.5	15.8	13.7	30.3	17.8	35.2	53.0	16.7
56-94	0	0.0	0.1	0.5	18.8	15.5	34.9	15.6	30.6	46.2	18.8
94-119	0	0.1	0.4	0.9	17.5	13.7	32.6	15.3	29.7	45.0	22.4
119-130	0	0.2	0.6	1.8	20.9	12.6	36.1	14.3	27.0	41.3	22.5
130-145	0	0.6	1.8	3.3	14.3	8.3	28.3	12.8	30.2	43.0	28.8

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
0-7	0.790	-	-	8.6	16.4
7-24	-	-	-	9.3	16.0
54-94	0.770	-	-	-	-
24-56	-	-	-	0.0	16.7
95-125	0.800	-	-	-	-
125-140	0.780	-	-	-	-
56-94	-	-	-	0.0	18.8
94-119	-	-	-	0.0	22.4
119-130	-	-	-	0.0	22.5
130-145	-	-	-	0.0	28.8

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
0-7	0.790	63.4	63.1	57.6	52.2	50.3	48.5	34.0	27.0
54-94	0.770	67.0	67.0	62.2	57.6	55.7	53.4	36.1	32.3
95-125	0.800	67.4	67.4	61.7	55.1	52.7	50.0	40.5	36.8
125-140	0.780	71.3	70.4	64.1	58.3	55.4	51.5	45.3	41.3

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
0-7	5.2	4.6	0.22	-	3.40	0.28	12	0.2	0.2	4.9	0.6	0.3	0.8	6.6
7-24	5.5	4.8	0.13	-	2.89	0.39	7	0.1	0	4.8	0.4	0.2	0.2	5.6
24-56	5.8	5.0	0.05	-	2.16	0.20	11	0.1	0	1.3	0.2	0.0	0.0	1.5
56-94	5.9	5.2	0.03	-	1.63	0.17	10	0.1	0	1.0	0.2	0.1	0.0	1.3
94-119	6.2	4.9	0.02	-	1.10	0.11	10	0.1	0	1.0	0.1	0.4	0.0	1.5
119-130	6.2	4.8	0.02	-	0.66	0.08	8	0.1	0	2.0	0.3	1.2	0.1	3.6
130-145	6.4	4.7	0.02	-	0.49	0.07	7	0.1	0	3.5	0.6	0.6	0.3	5.0

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	53	12.4	76	11.9	-	2	6
7-24	49	11.5	72	10.2	-	0	2
24-56	17	8.8	53	7.7	-	0	0
56-94	12	11.1	59	5.6	-	0	0
94-119	10	14.5	65	3.9	-	0	0
119-130	30	12.2	54	2.5	-	0	1
130-145	32	15.7	55	1.8	-	0	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
0-7	10.1	75	-	1.50	0.70	0.70	0.50	0.40	0.60	-	0.50
7-24	10.2	79	-	1.50	0.70	0.80	0.50	0.40	0.50	-	0.50
24-56	10.4	85	-	1.70	1.00	0.80	0.50	0.20	0.40	-	0.40
56-94	10.1	91	-	2.50	1.70	1.00	0.50	0.10	0.40	-	0.40
94-119	9.5	94	-	2.40	1.60	1.60	0.80	0.10	0.30	-	0.30
119-130	9.2	81	-	2.00	1.50	2.50	1.00	0.10	0.20	-	0.40
130-145	8.8	80	-	2.10	1.50	2.10	0.90	0.10	0.20	-	0.80

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-7	weak	very weak	-	-	-	-	very weak to weak	-	-	-	-	-
7-24	weak	very weak	-	-	-	-	very weak to weak	-	-	-	-	-
24-56	weak	very weak to weak	-	-	-	-	very weak to weak	-	-	-	-	-
56-94	very weak	very weak	-	-	weak	-	-	-	-	-	-	-
94-119	weak	very weak	-	-	weak	-	very weak to weak	-	-	-	-	-
119-130	weak	-	-	-	-	-	very weak to weak	-	-	-	-	-
130-145	-	very weak	-	-	weak	-	-	-	-	-	-	-

Profile description

Ah 0-7 cm	dark brown (10YR 3/3, moist)loam,weak coarse subangular blocky,friable non sticky non plastic,common very fine fine tubular pores,very few pottery inclusions,clear irregular boundary to,
Bw1 7-24 cm	(dark) brown (10YR 4/3, moist)silt loam,weak medium subangular blocky,very friable slightly sticky slightly plastic,many very fine fine tubular pores and many interstitial pores,very few pottery inclusions,gradual wavy boundary to,
Bw2 24-56 cm	(dark) brown (10YR 4/3, moist)silt loam,weak coarse angular blocky parting to weak medium subangular blocky,friable non sticky non plastic,common very fine fine tubular pores,very few pottery inclusions,gradual wavy boundary to,
2Ab 56-94 cm	very dark greyish brown (10YR 3/2, moist)loam,weak coarse angular blocky parting to weak medium subangular blocky,friable non sticky non plastic,common very fine fine tubular pores and many interstitial pores,gradual wavy boundary to,
2C 94-119 cm	(dark) brown (10YR 4/3, moist)loam,weak coarse angular blocky parting to weak medium subangular blocky,friable slightly sticky slightly plastic,common very fine fine tubular pores and many interstitial pores,clear wavy boundary to,
2Cg 119-130 cm	(10YR 5/1.5, moist)fine sandy loam,weakly coherent porous massive,friable non sticky non plastic,common fine distinct mottles (10 YR 4/4) and common medium prominent mottles (2.5 Y 4/2),common very fine tubular pores and many interstitial pores,abrupt irregular boundary to,
3Ab 130-145 cm	very dark greyish brown (10YR 3/2, moist)silt loam,weakly coherent porous massive,friable non sticky non plastic,many very fine tubular pores and many interstitial pores,

Kind 1 (parent material) ; Parker (eds), 1984	pyroclastic, unconsolidated
Mode of accumulation or deposition of parent material	ejecta ash
Remarks on Parent Materials	several ash deposits
Soil Depth	145cm
Texture of parent material	loamy
Weathering Resistance	poor
General characterization of the status of weathering of solid rock	slightly

Major crops	oil palm
Land improvements ; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	land improvements - not specified
Land use or vegetation in the immediate vicinity of the site	high level mixed farming
Remarks on Land Use / Vegetation	VEGETATION: forest cleared, now oil palm and pasture LANDUSE: Twenty years ago the area was frequently flooded by the Rio Blanco (and Rio Quininde), now the area is protected against flooding
Major vegetation type; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	evergreen forest

Altitude	280m
Physiographic Unit	broad low interfluve
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 terrace
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
Flooding frequency (FAO, 1986)	never
Depth to groundwater table	200cm
Kind of ground water table (USDA, 1979)	groundwater table observed
Moist From - To	0-110cm
Estimated permeability (class) of least permeable part of the profile	moderate
Estimated run off (class)	slow
Wet From To	110-190cm

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 09: Andosol

Characteristics

Reference soil EC009: Andosols

Classification