Reference soil Colombia 8: Acrisol

Code: 
CO008
Collection date: 
January, 1981
Soil surveyor: 
Siderius W
Location: 
Approximately 10km NE of Araracuara (Caqueta)
Climate classification: 
Af
Classification: 

WRB 2006:

WRB 1998:

Cutanic Acrisol(Alumic Humic Profondic)
Profondi- Humic Acrisol(Alumic Chromic)
21-150 cm argic horizon  
0-21 cm ochric horizon  
21-150 cm argic horizon  
strongly humic properties  

 

FAO-UNESCO-ISRIC 1988:

FAO-UNESCO 1974:

Humi- Haplic Acrisol
Ferric Acrisol
0-21 cm ochric A horizon  
21-150 cm argic B horizon  
strongly humic  
0-21 cm ochric A horizon  
21-150 cm argillic B horizon  
ferric properties
Physiography: 
The altitude of the soil profile relative to mean sea level, specified in meters 230 m asl
Regional landform plain
Topography of the surrounding country undulating
Physiographic Unit in the immediate surrounding of the site denud.sedimentary upland plain
The slope refers to the inclination of the land immediately surrounding the site. The measured or estimated slope angle is specified to the nearest per cent 3 %
The physiographic position of the site where the profile is located upper slope
Form of the slope surrounding the site straight
Slope Aspect of the site north-east
Parent material: 
The main parent rock/ material over which the soil has been formed (1st entry)  
Mode of Accumulation or deposition of parent material (1st entry) unconsolidated, unspecified
Texture of parent material (1st entry) clayey
Remarks on Parent Materials
Hydrology and drainage: 
Drainage Class well
Land use: 
Current land use at the site (semi-)natural vegetation
Vegetation Type;The natural vegetation at the site evergreen forest
Status of vegetation primary
Remarks on Land Use / Vegetation VEGETATION: Palm trees LANDUSE: Hunting and food gathering
Surface characteristics: 
Evidence of salt non-saline
Evidence of alkali non-alkaline

Nearest climate station:

Station : No representative climate station available for this site

Profile description:

Ah 0-8 cm : dark brown (7.5YR 3/2, moist) , sandy clay loam , weak fine subangular blocky , soft friable slightly sticky slightly plastic , many fine to coarse tubular pores , gradual smooth boundary to ,
AB 8-21 cm : (dark) brown (7.5YR 4/4, moist) , sandy clay loam , weak fine subangular blocky , slightly hard friable sticky plastic , common many fine to coarse tubular pores , charcoal inclusions , few fine gravel charcoal fragments , frequent coprogenic elements , gradual smooth boundary to ,
Bt1 21-50 cm : reddish brown (5YR 4/4, moist) , clay , moderate fine subangular blocky , friable sticky plastic , patchy moderately thick cutans , common fine tubular pores and common pores , charcoal inclusions , few charcoal fragments , frequent pedotubules , gradual smooth boundary to ,
Bt2 50-75 cm : (5YR 4/8, moist) , clay , moderate fine angular blocky , friable sticky very plastic , broken moderately thick cutans , few fine tubular pores and common pores , charcoal , charcoal inclusions , few charcoal fragments , frequent pedotubules , gradual smooth boundary to ,
Bto 75-100 cm : red (2.5YR 4/6, moist) , clay , weak to moderate fine angular blocky , friable sticky very plastic , broken moderately thick cutans , few few fine medium tubular pores and common common tubular pores , few quartz grain fragments , few pedotubules , diffuse smooth boundary to ,
Bo 100-150 cm : red (2.5YR 4/8, moist) , clay , weak to moderate fine angular blocky , friable sticky very plastic , broken moderately thick cutans , few few fine medium tubular pores and common common tubular pores , few pedotubules ,

Physical

Particle size distribution:

Depth (cm)   Gravel (%) Very Coarse Sand (%) Coarse Sand (%) Medium Sand (%) Fine Sand (%) Very Fine Sand (%) Total Sand (%) Coarse Silt (%) Fine Silt (%) Total Silt (%) Clay (%)
0-8 : - 0.7 1.7 7.9 21.1 6.2 37.6 5.5 10.1 15.6 46.7
8-21 : - 0.2 0.7 4.2 17.3 6.3 28.7 6.9 11.1 18.0 53.2
21-50 : - 0.3 0.6 3.7 13.5 5.4 23.5 4.8 11.5 16.3 60.2
50-75 : - 0.1 0.7 2.8 12.1 4.8 20.5 5.0 10.6 15.6 63.9
75-100 : - 0.2 0.5 2.5 11.5 4.3 19.0 3.0 12.8 15.8 65.3
100-150 : - 0.6 0.5 2.5 10.2 4.0 17.8 6.9 12.8 19.7 62.5

Water retention characteristics

Depth (cm)   Bulk Density (kg/dm³) pF 0 (% w/v) pF 1.0 (% w/v) pF 1.5 (% w/v) pF 2.0 (% w/v) pF 2.3 (% w/v) pF 2.7 (% w/v) pF 3.4 (% w/v) pF 4.2 (% w/v) pF 2.5 (%)
20-28 : 1.010 59.8 54.6 50.2 47.3 45.7 44.6 38.2 36.0 -
60-68 : 1.100 56.6 55.6 53.4 50.9 49.8 48.7 44.8 42.7 -
105-113 : 1.150 58.0 57.3 55.0 52.9 51.8 50.6 47.3 45.5 -

Other physical data

Depth (cm)   Bulk Density (kg/dm³) Spec. Surf. Area (m2/g) COLE (cm/cm) Water Disp. Clay (%) Clay (%)
0-8 : - - - 10.7 46.7
8-21 : - - - 10.4 53.2
21-50 : - - - 0.2 60.2
50-75 : - - - 0.4 63.9
75-100 : - - - 0.0 65.3
100-150 : - - - 0.0 62.5

Chemical characteristics:

Depth (cm)   pH H2O pH KCl EC 1 : 2.5 (mS/cm) CaCO3 (%) Org. C (%) Org. N (%) C / N Exch. Acid (cmol/kg) Exch. Al (cmol/kg) Ca (cmol/kg) Mg (cmol/kg) K (cmol/kg) Na (cmol/kg) Sum Cations (cmol/kg)
0-8 : 3.7 3.6 0.21 - 6.46 0.40 16 - - 0.0 0.0 0.0 0.1 0.1
8-21 : 4.2 3.9 0.13 - 1.56 0.14 11 - - 0.4 0.0 0.0 0.0 0.4
21-50 : 4.5 3.9 0.04 - 0.89 0.09 10 - - 0.0 0.0 0.0 0.3 0.3
50-75 : 4.9 3.9 0.02 - 0.63 - - - - 0.0 0.1 0.1 0.0 0.2
75-100 : 4.9 3.9 0.02 - 0.47 - - - - 0.0 0.0 0.0 0.0 0.0
100-150 : 5.0 3.9 0.01 - 0.36 - - - - 0.0 0.0 0.1 0.0 0.1

 

Depth (cm)   CEC Soil (cmol/kg) CEC Clay (cmol/kg) CEC Org (cmol/kg) ECEC (cmol/kg) Base sat. (%) Al sat. (%) ESP (%)
0-8 : 31.0 - 22.6 - 0 - 0
8-21 : 14.4 - 5.5 - 3 - 0
21-50 : 13.3 - 3.1 - 2 - 2
50-75 : 10.8 - 2.2 - 2 - 0
75-100 : 9.9 - 1.6 - 0 - 0
100-150 : 13.2 - 1.3 - 1 - 0

 

Depth (cm)   pH NaF P Retention (%) ODOE Melanic Index Fe o (wt%) Al o (wt%) Si o (wt%) Fe d (wt%) Al d (wt%) Fe p (wt%) Al p (wt%) C p (wt%)
0-8 : - - - - 0.29 0.37 0.01 2.69 0.95 - - -
8-21 : - - - - 0.27 0.24 0.03 3.14 0.90 - - -
21-50 : - - - - 0.09 0.31 0.04 3.61 0.84 - - -
50-75 : - - - - 0.05 0.17 0.03 3.76 0.86 - - -
75-100 : - - - - 0.04 0.23 0.06 4.07 0.81 - - -
100-150 : - - - - 0.04 0.20 0.03 4.88 0.72 - - -

 

Clay mineralogy:

Depth (cm)   Kaolinite Mica / illite Vermiculite Chlorite Smec Halloysite Mixed layer Quar Feldspar Gibbsite Goethite Hematite
0-8 : very strong - weak - - - - medium to strong medium to strong - - -
8-21 : very strong - medium to strong - - - - weak - - - -
21-50 : very strong - medium to strong - - - - very weak - - - -
50-75 : very strong - weak - - - - very weak - - - -
75-100 : very strong - weak - - - - very weak - - - -
100-150 : very strong - weak - - - - very weak - - - -