Soil type characteristics:
Alisols occur in the tropics and subtropics, and in the warm temperate regions of the world in relatively young landscapes. The high level of exchangeable aluminium in these soils is caused by rapid weathering of secondary high-activity clays such as vermiculite and smectite.
Characteristics
Soils having an argic horizon (a subsurface horizon with distinct higher clay content than the overlying horizon), which has a cation exchange capacity of 24 cmolc per kg clay or more, and which starts either within 100 cm from the soil surface, or within 200 cm from the soil surface if the argic horizon is overlain by loamy sand or coarser textures throughout. They have "alic" properties (high content of exchangeable aluminium) in the major part between 25 and 100 cm from the soil surface; moreover, only such diagnostic horizons as an ochric, albic, andic, ferric, nitic, plinthic, or vertic horizon are present.
Distribution of Alisols (rough estimation supplied by soilgrids)
Description:
Reference soil CN047: Alisols
PROFILE DESCRIPTION : Deep, well drained, strong brown clay to silty clay developed from solid rock derived from shale. GENERAL LANDFORM: in between the low mountains and hills, small valleys are found, filled with colluvium, where irrigated rice is cultivated. The different geomorphological units form part of the broad Pingba basin / PARENT MATERIAL: the soil is developed on shale, outcropping in the inmediate surroundings in form of some low steep bare mountains / SOIL DEPTH: hills which are more gently sloping have a thick solumn (yellow earth) and the parent material is at relatively great depth / GENERAL SOIL INFORMATION: nearby yellowish red coloured soils on Quaternary clay (CN048) are also classified as Yellow soils in the new Chinese soil classification.
General information:
| Authors | Vogel AW, Wang Mingzhu & Huang Xiaoqing |
| Köppen | Cwa |
| Location | Pingba County, Gaofeng municipality, Lubacan village |
| Date | 1993-07-01 |
| Lat/Lon | 26.3833, 106.4333 |
Code:
CN047
Parent material
| Kind 1 (parent material) ; Parker (eds), 1984 | shale |
| Remarks on Parent Materials | more than 2.5m depth |
| General characterization of the status of weathering of solid rock | slightly |
| Mode of accumulation or deposition of parent material | residual material |
| Soil Depth | 150cm |
Physiography
| Physiographic Unit | lower hill, Pingba Basin |
| Form of the slope surrounding the site | convex |
| Altitude | 1230m |
| Slope Aspect | north |
| Physiographic position of the site | upper slope |
| Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006) | undulating |
| Slope | 2% |
| Regional landform; McDonald, R.C., Isbell, R.F. et all, 1984; Australian soil and land survey Field Handbook, Inkata Press, Melbourne. | low hill |
Hydrology and drainage
| Moist From - To | 0-110cm |
| Wet From To | 110-150cm |
| Kind of ground water table (USDA, 1979) | no groundwater table observed |
| Estimated run off (class) | medium |
| Flooding frequency (FAO, 1986) | never |
| Drainage class ; FAO (2006) - Guidelines for soil description | well |
Erosion and degradation
| Slope stability | stable |
| Occurrence of soil aggradation (McDonald et al., 1984) | absent |
| Intensity of the soil erosion type (second entry) | slight |
| Soil erosion type | sheet |
| Intensity of the soil erosion type | slight |
| Soil erosion type (second entry) | rill |
Land use
| Remarks on Land Use / Vegetation | LANDUSE: Undergrowth of grasses eaten by cattle |
| Land use or vegetation in the immediate vicinity of the site | low level arable farming |
| Major crops | tea |
Surface characteristics
| Average size of stone | 15 |
| Shape of stones (on average) | platy or flat |
| Evidence of salt; Soil Survey Manual USDA, 1951 | non-saline |
| Rock outcrop class (FAO (2006) - Guidelines for soil description) | none |
| Surface cracking | no cracks observed |
| Slaking of aggregates by tillage, rainfall or frost (USDA/SCS, 1979) | no surface slaking/crusting observed |
| Evidence of alkali ; Soil Survey Manual USDA, 1951 | non-alkaline |
| Microrelief Height: variation in height | 10 |
| Micro relief type: small-scale differences in relief in the direct vicinity of the site (FAO, 1986) | knobs |
| Surface stoniness class (FAO (2006) - Guidelines for soil description) | very few stones |
Classification
WRB 2006
| Cutanic Alisols (Alumic Clayic ) |
| 15-140 | argic horizon |
WRB 1998
| Cutanic Dystri Luvisols |
| 0-15 cm | ochric horizon |
| 15-140 cm | argic horizon |
FAO-UNESCO-ISRIC 1974
| Orthic Acrisols |
| - | ferric horizon |
| 0-15 cm | ochric A horizon |
| 15-140 cm | argillic B horizon |
Local classification
| Classification information | Argillic yellow soil; Hapli-Perudic Argosol |
| Common name | Yellow claypan soil |
Other classification
| USDA-NRCS (1999) | Typic Hapludult |
| USDA-SCS (1975) | Typic Hapludult perudic clayey mixed mesic |
Other
| Description of a site | PROFILE DESCRIPTION : Deep, well drained, strong brown clay to silty clay developed from solid rock derived from shale. GENERAL LANDFORM: in between the low mountains and hills, small valleys are found, filled with colluvium, where irrigated rice is cultivated. The different geomorphological units form part of the broad Pingba basin / PARENT MATERIAL: the soil is developed on shale, outcropping in the inmediate surroundings in form of some low steep bare mountains / SOIL DEPTH: hills which are more gently sloping have a thick solumn (yellow earth) and the parent material is at relatively great depth / GENERAL SOIL INFORMATION: nearby yellowish red coloured soils on Quaternary clay (CN048) are also classified as Yellow soils in the new Chinese soil classification. |
Climate data
| Description | record | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Bright sunshine (%) | 21 | 16 | 18 | 26 | 34 | 28 | 25 | 43 | 45 | 36 | 24 | 23 | 17 | 27.9 |
| Maximum temperature (°C) | 21 | 8.1 | 10 | 16.2 | 21 | 23 | 24.7 | 26.7 | 26.5 | 24 | 19.1 | 14.2 | 10.2 | 18.6 |
| Mean temperature (°C) | 999 | 3.9 | 5.5 | 10.7 | 15.4 | 18.4 | 20.6 | 22.4 | 21.6 | 18.9 | 14.8 | 10.1 | 6.1 | 14 |
| Minimum temperature (°C) | 21 | 1.2 | 2.4 | 7.1 | 11.4 | 15.3 | 17.5 | 19.3 | 18.4 | 15.5 | 11.9 | 7.4 | 3.4 | 10.9 |
| Precipitation (mm) | 21 | 17.7 | 18.9 | 31.8 | 122.6 | 202.3 | 264.4 | 179.2 | 168.8 | 120.2 | 104.4 | 49.6 | 23.8 | 1303.7 |
| Relative humidity (%) | 21 | 83 | 83 | 80 | 79 | 81 | 82 | 83 | 84 | 83 | 84 | 83 | 84 | 82.4 |
| Act. Evapotranspiration (mm) | 28 | 49.6 | 63 | 110.9 | 143.1 | 141.8 | 130.1 | 158.5 | 150.4 | 121.5 | 84.1 | 64.1 | 48.1 | 1265.2 |
| Bright sunshine (hours/day) | 27 | 1.9 | 2.3 | 3.5 | 4.6 | 3.9 | 3.7 | 5.5 | 5.4 | 4.4 | 3 | 2.6 | 1.9 | 3.6 |
| Number of rain days | 30 | 14.9 | 14.1 | 13.8 | 15.7 | 20.2 | 19.3 | 19.1 | 17.4 | 14.3 | 17.2 | 13.8 | 13.5 | 193.3 |
| Precipitation (mm) | 30 | 17.6 | 19.6 | 28.7 | 92.1 | 228.1 | 264.6 | 241.1 | 180.7 | 118.6 | 102.5 | 43.8 | 24.2 | 1361.6 |
| Total global radiation (MJ/m²) | 999 | 5.7 | 7.1 | 10.2 | 13.3 | 13.3 | 12.7 | 15.6 | 15.1 | 12.4 | 8.5 | 6.9 | 5.5 | 10.5 |
| Windspeed (m/s, at 2m height) | 27 | 1.9 | 2.2 | 2.3 | 2.3 | 2.1 | 1.8 | 2 | 1.5 | 1.7 | 1.8 | 1.8 | 1.8 | 1.9 |
| Station: | Pingba |
| Country: | China |
| WMO Code: | 99.999 |
| Altitude: | 0 |
| Latitude/Longitude | N26°25 E106°16 |
Profile description
| Ah 0-15 cm | dark yellowish brown (10YR 4/4, moist)clay,moderate fine subangular blocky to moderate medium granular,firm,common very fine inped pores highly porous (>60 vol%),very few small irregular hard unspecified unspecified inclusions very few small irregular soft unspecified unspecified inclusions,frequent pedotubules,abrupt smooth boundary to, |
| Bt1 15-50 cm | strong brown (7.5YR 5/8, moist)clay,moderate to strong fine and medium subangular blocky,firm,continuous clay and humus on pedfaces cutans,many very fine inped pores and common inped pores highly porous (>60 vol%),few pedotubules,abrupt smooth boundary to, |
| Bt2 50-110 cm | strong brown (7.5YR 5/8, moist)clay,moderate to strong fine and medium subangular blocky to moderate to strong medium columnar,friable,continuous clay and humus in root channels and pores cutans,many very fine inped pores and common inped pores highly porous (>60 vol%),few pedotubules,clear wavy boundary to, |
| BC 110-140 cm | reddish yellow (7.5YR 6/8, moist)silty clay,moderate medium columnar,very friable non sticky,common medium distinct sharp mottles (7.5YR 6/8),broken clay and humus in root channels and pores cutans,many very fine inped pores and many inped pores highly porous (>60 vol%),clear boundary to, |
| C 140- cm | yellow (10YR 7/6, moist)silty clay,weak to moderate medium columnar to weak to moderate medium subangular blocky,very friable non sticky,many very fine inped pores and many inped pores moderately porous (40-60 vol%), |
Chemical characteristics
| Depth (cm) | C % weight/weight | Ca cmol(c)/kg | CaCO3 % weight/weight | C / N unitless | EC 1: 2.5 mS/cm | Exch. Acid cmol(c)/kg | Exch. Al cmol(c)/kg | K cmol(c)/kg | Mg cmol(c)/kg | N % | Na cmol(c)/kg | pH H2O unitless | pHKCl unitless | Sum Cations cmol(c)/kg |
| 0-15 | 1.92 | 4.3 | - | 10 | 0.08 | 8.6 | 6.9 | 0.4 | 1.4 | 0.19 | 0.2 | 4.9 | 4.1 | 6.3 |
| 15-50 | 0.56 | 2.9 | - | 6 | 0.03 | 9.8 | 8.1 | 0.2 | 0.7 | 0.09 | 0.0 | 5.1 | 4.0 | 3.8 |
| 50-110 | 0.29 | 2.8 | - | 6 | 0.01 | 10.6 | 8.2 | 0.2 | 0.7 | 0.05 | 0.2 | 5.3 | 4.1 | 3.9 |
| 110-140 | 0.16 | 1.3 | - | 3 | 0.04 | 10.4 | 8.7 | 0.2 | 0.4 | 0.06 | 0.2 | 5.4 | 4.1 | 2.1 |
| 140-140 | 0.15 | 1.2 | - | 3 | 0.04 | 10.6 | 8.5 | 0.3 | 0.3 | 0.06 | 0.1 | 5.3 | 4.0 | 1.9 |
| Depth (cm) | Al sat. % | Base sat. % | CEC clay cmol(c)/kg | CEC org cmol(c)/kg | CEC soil cmol(c)/kg | ECEC cmol(c)/kg | ESP % |
| 0-15 | 41 | 38 | 29 | 6.7 | 16.8 | - | 1 |
| 15-50 | 55 | 26 | 22 | 2.0 | 14.7 | - | 0 |
| 50-110 | 47 | 22 | 30 | 1.0 | 17.6 | - | 1 |
| 110-140 | 60 | 14 | 28 | 0.6 | 14.6 | - | 1 |
| 140-140 | 55 | 12 | 33 | 0.5 | 15.4 | - | 1 |
| Depth (cm) | CaSO4.2H2O % | P Bray mg/kg | pH CaCl2 unitless | P Olsen mg/kg |
| 0-15 | - | 8.4 | - | 8.8 |
| 15-50 | - | 0.0 | - | 1.6 |
| 50-110 | - | 0.0 | - | 0.4 |
| 110-140 | - | 0.0 | - | 1.8 |
| 140-140 | - | 0.0 | - | 1.9 |
Physical characteristics
Particle size distribution
| Depth (cm) | Clay % weight/weight | coarse sand % weight/weight | coarse silt % weight/weight | fine sand % weight/weight | fine silt % weight/weight | Gravel % volume/volume | medium sand % weight/weight | Total sand % weight/weight | Total silt % weight/weight | very coarse sand % weight/weight | very fine sand % weight/weight |
| 0-15 | 57.8 | 1.3 | 5.6 | 1.4 | 30.3 | - | 1.3 | 6.3 | 35.9 | 1.2 | 1.1 |
| 15-50 | 67.3 | 0.1 | 2.1 | 0.4 | 29.0 | - | 0.2 | 1.7 | 31.1 | 0.2 | 0.8 |
| 50-110 | 59.6 | 0.4 | 3.0 | 1.5 | 33.7 | - | 1.0 | 3.7 | 36.7 | 0.1 | 0.7 |
| 110-140 | 52.8 | 0.5 | 2.8 | 2.4 | 38.9 | - | 1.5 | 5.7 | 41.7 | 0.1 | 1.2 |
| 140-140 | 47.3 | 0.7 | 5.3 | 2.6 | 41.3 | - | 1.7 | - | 46.6 | 0.1 | 0.9 |
Other physical data
| Depth (cm) | Bulk density kg/dm³ | Clay % weight/weight | COLE cm/cm | Spec. Surf. Area m²/g | Water disp. clay % |
| 0-15 | 1.261 | 57.8 | - | - | - |
| 15-50 | 1.090 | 67.3 | - | - | - |
| 50-110 | 1.083 | 59.6 | - | - | - |
| 110-140 | - | 52.8 | - | - | - |
| 140-140 | - | 47.3 | - | - | - |
Water retention characteristics
| Depth (cm) | Bulk density kg/dm³ | pF 0 % volume/volume | pF 1.0 % volume/volume | pF 1.5 % volume/volume | pF 2.0 % volume/volume | pF 2.3 % volume/volume | pF 2.7 % volume/volume | pF 3.4 % volume/volume | pF 4.2 % volume/volume |
| 0-15 | 1.261 | 55.7 | 54.2 | 51.7 | 47.7 | 45.5 | 43.3 | 41.9 | 37.3 |
| 15-50 | 1.090 | 62.4 | 60.6 | 59.7 | 58.4 | 57.8 | 57.0 | 49.2 | 44.2 |
| 50-110 | 1.083 | 64.2 | 64.0 | 63.4 | 62.7 | 62.2 | 61.6 | 50.1 | 45.6 |
Clay mineralogy
| Depth (cm) | Chlorite unitless | Feldspar unitless | Gibbsite unitless | Goethite unitless | Halloysite unitless | Hematite unitless | Kaolinite unitless | Mica / illite unitless | Mixed-layer unitless | Quartz unitless | Smec unitless | Vermiculite unitless |
| 0-15 | - | - | - | weak | - | - | medium to strong | weak | medium to strong | - | weak | weak |
| 15-50 | - | - | - | weak | - | - | medium to strong | weak | medium to strong | - | weak | weak |
| 50-110 | - | - | - | medium to strong | - | - | medium to strong | medium to strong | medium to strong | - | weak | weak |
| 110-140 | - | - | - | medium to strong | - | - | medium to strong | medium to strong | medium to strong | - | weak | weak |
| 140-140 | - | - | - | medium to strong | - | - | medium to strong | medium to strong | medium to strong | - | weak | weak |
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