Reference soil Brazil 19: Podzol

BR019

Podzols mainly occur in cool temperate and moist regions on coarse textured materials. Areas of Podzols have also been recorded from wet, tropical regions, notably the Amazon basin, southern central Africa and southeast Asia.

Characteristics

Soils having a spodic horizon (a dark coloured subsurface horizon with illuvial amorphous alumino-organic substances) within 200 cm from the soil surface, underlying an albic, histic, umbric or ochric horizon, or an anthropedogenic horizon less than 50 cm thick. Podzols are probably the most extensively researched group of soils.

Distribution of Podzols (rough estimation supplied by soilgrids)

Reference soil BR019: Podzols

Deep, moderately well drained sandy soil derived from Tertiary sediments; having a strongly cemented impermeable iron layer in the deeper subsoil. Brazilian classification: Podzol com duripan or Podzol hidromorfico. *Geomorphology: dissected plain ("Tabuleiro") developed in Tertiary sediments of the "Barreiras" group. The genesis of these sediments is not yet understood. Lateral groundwater flow over impermeable iron pan. Seepage zones on lower slope. Imperfectly to moderately well Drained. Major crops: roots like 'inhame' (Dioscoreaceae), cassava, sweet potato. Additional information: Boletim Tecnico no 35 (ISRIC-library), slides 9821-9826. Classification: the iron & duripan is situated at a depth than 100cm, it therefore does not classify as Placorthord or Durorthod.

Classification

WRB 2006

WRB 1998

Albic-Ortsteinic- Podzol

Densic- Podzol

110-150 cm	spodic horizon
20-110 cm	albic horizon

0-20 cm	ochric horizon
110-150 cm	spodic horizon
20-110 cm	albic horizon

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Spodi-Albic Arenosol

Albic Arenosol duripan

0-20 cm	ochric A horizon
110-150 cm	spodic B horizon
20-110 cm	albic E horizon
- cm	spodic B horizon

0-20 cm	ochric A horizon
110-150 cm	spodic B horizon
20-110 cm	albic E horizon
-	albic material

Local classification:	Podzol com duripan

Other classification

USDA-NRCS (1999)	Typic Haplorthod
USDA-SCS (1975)	ustic sandy siliceous 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
0-20	-	2.8	21.0	39.6	26.0	5.0	94.4	1.7	1.4	3.1	2.5
20-70	-	2.3	16.3	35.5	33.0	7.2	94.3	2.3	1.3	3.6	2.0
70-110	-	5.6	17.7	31.3	33.1	7.3	95.0	2.6	0.7	3.3	1.7
110-116	4	6.5	17.1	27.9	31.9	7.3	90.7	3.3	1.0	4.3	5.0
116-126	13	2.9	15.6	26.0	23.6	8.1	76.2	8.7	5.2	13.9	10.1
126-150	60	2.6	16.9	29.6	23.7	8.7	81.5	6.9	8.2	15.1	3.4

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
0-20	-	-	-	0.9	2.5
10-15	1.391	-	-	-	-
20-70	-	-	-	0.4	2.0
90-95	1.617	-	-	-	-
70-110	-	-	-	0.4	1.7
110-116	-	-	-	1.3	5.0
116-126	-	-	-	2.5	10.1
126-150	-	-	-	0.9	3.4

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
10-15	1.391	44.2	42.0	21.7	8.2	7.2	6.3	2.9	2.9
90-95	1.617	33.9	32.3	23.0	5.0	3.4	2.8	1.4	1.4

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
0-20	5.2	4.3	0.04	-	0.65	0.05	13	0.4	0.2	0.2	0.1	0.0	0.1	0.4
20-70	5.6	4.2	0.01	-	0.42	0.04	10	0.5	0.5	0.2	0.0	0.0	0.1	0.3
70-110	5.6	4.4	0.01	-	0.16	0.01	16	0.2	0	0.2	0.0	0.0	0.1	0.3
110-116	5.2	4.4	0.02	-	0.48	0.04	12	0.5	0.5	0.0	0.0	0.0	0.0	0.0
116-126	5.1	4.4	0.02	-	1.11	0.05	22	1.0	0.9	0.2	0.0	0.1	0.1	0.4
126-150	4.9	5.0	0.02	-	0.85	0.03	28	0.2	0	0.2	0.0	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 %
0-20	25	1.6	64	2.3	-	13	6
20-70	13	2.3	115	1.5	-	22	4
70-110	60	0.5	29	0.6	-	0	20
110-116	0	2.1	42	1.7	-	24	0
116-126	8	4.8	48	3.5	-	19	2
126-150	27	1.1	32	2.1	-	0	9

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
0-20	-	-	-	0.00	0.00	0.00	0.00	-	-	-	0.00
20-70	-	-	-	0.00	0.00	0.00	0.00	-	-	-	0.00
70-110	-	-	-	0.00	0.00	0.00	0.00	-	-	-	0.00
110-116	-	-	-	0.10	0.00	0.00	0.10	-	-	-	0.00
116-126	-	-	-	-	-	0.00	0.50	-	-	-	-
126-150	-	-	-	-	-	0.20	0.50	-	-	-	-

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-20	-	weak	-	weak	-	-	medium to strong	-	-	weak	-	-
20-70	-	weak	-	weak	-	-	medium to strong	-	-	weak	-	-
70-110	-	weak	-	weak	-	-	medium to strong	weak	-	weak	-	-
110-116	-	weak	-	weak	-	-	medium to strong	-	-	weak	-	-
116-126	-	weak	-	weak	-	-	medium to strong	-	-	weak	-	-
126-150	-	weak	weak	weak	-	-	medium to strong	-	-	weak	-	-

Profile description

Ah 0-20 cm	grey (10YR 5/1, dry) very dark grey (10YR 3/1, moist)Description sand,structureless single grain,loose non sticky non plastic,many very fine interstitial random pores,clear smooth boundary to,
E1 20-70 cm	(light) grey (10YR 6/1, dry) very dark grey (10YR 3/1, moist)Description sand,structureless single grain,loose non sticky non plastic,many very fine micro random pores,gradual smooth boundary to,
E2 70-110 cm	light grey (10YR 7/1, dry) (10YR 5.5/2, moist)Description sand,structureless single grain,loose non sticky non plastic,many very fine micro random pores,abrupt wavy boundary to,
Bh 110-116 cm	dark greyish brown (10YR 4/2, moist)Description sand,structureless single grain,loose non sticky non plastic,many very fine interstitial random pores,abrupt wavy boundary to,
Bhsm 116-126 cm	pale brown (10YR 6/3, moist)Description sand,strongly coherent massive,very hard extremely firm,common fine prominent clear mottles (7.5 YR 5/8),continuous massive strongly cemented iron pan pans,abrupt wavy boundary to,
Bsm 126-150 cm	brownish yellow (10YR 6/6, moist)Description sand,strongly coherent massive,extremely hard extremely firm,common fine prominent clear mottles (7.5 YR 5/8),continuous massive indurated pans,

Kind 1 (parent material) ; Parker (eds), 1984	sediment, unconsolidated
Mode of accumulation or deposition of parent material	marine sediments
Remarks on Parent Materials	Tertiary sediments of the "Barreiras" group; the genesis of these sediments is not yet well-understood
Soil Depth	116cm
Texture of parent material	sandy
Weathering Resistance	high
General characterization of the status of weathering of solid rock	partially or moderately

Occurrence of soil aggradation (McDonald et al., 1984)	not apparent
Intensity of the soil erosion type	slight
Soil erosion type	sheet
Slope stability	stable

Major crops	root crops
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	low level arable farming
Remarks on Land Use / Vegetation	VEGETATION: LANDUSE: Inhame (Dioscoreaceae), cassava, sweet potato
Rotation scheme ; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	shifting - fallow grass
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	50m
Physiographic Unit	broad low hill in dissected plain ("Tabuleiro")
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.	marine terrace
Slope	6%
Slope Aspect	north-east
Form of the slope surrounding the site	convex
Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	rolling

Lower limit of a slow permeable or stagnating layer in the profile	150cm
Drainage class ; FAO (2006) - Guidelines for soil description	imperfect
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	slow
Estimated run off (class)	rapid
Drainage class - intergrade; FAO (2006) - Guidelines for soil description	moderately well
Upper limit of a slow permeable or stagnating layer in the profile	116cm

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
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 Brazil 19: Podzol

Characteristics

Reference soil BR019: Podzols

Classification