Reference soil China 38: Solonetz

CN038

Solonetzes occur where a sodium source supplies the clay-rich subsoil with exchangeable Na, causing peptization of clay and organic substances and deterioration of the topsoil.

Characteristics

Soils having a natric horizon (a subsurface horizon with distinct higher clay content than the overlying horizon and more than 15% exchangeable sodium) within 100 cm from the soil surface.

Distribution of Solonetz (rough estimation supplied by soilgrids)

Reference soil CN038: Solonetz

PROFILE DESCRIPTION : Very deep, poorly drained, dark brown to light yellowish brown silty clay loam derived from clayey lacustrine sediments. The soil has a very high amount of exchangeable sodium and a strongly alkaline reaction throughout. It occurs in close association with Gleyic Solonetz and Gleysols. No regular pattern can be found; slight differences in topography may result in a different soil type. LAND USE: area used for communal extensive (though over-)grazing (ox, sheep, horse). During the cultural revolution part of these soils have been irrigated with little success (1st year maize yield 3750 kg/ha (500 jin/mu), decreasing rapidly in the next years). Nearby Chernozems yield 9000 kg/ha 1200 jin/mu). An abandoned irrigation canal is present close to site. The Btn horizon of these soils is used for the roofs of houses (good protection against rain due to its loss of structure upon wetting) / EROSION: both overgrazing and digging for Btn soil material cause the severe wind and some water erosion of these soils. Furthermore the destruction of plant cover through gathering of medicinal herbs and cutting of grass for fuel (there are very few trees in the area!) adds to the erosion / CLIMATE: additional climatic data are available for the weather station of Anda (46 23 N/125 19 E; 149 m a.s.l.; 61 km NW of site; relevance: moderate) (see CN039). "

Classification

WRB 2006

WRB 1998

Stagnic- Solonetz (Humic)

Humi-Stagnic- Solonetz

35-90 cm	natric horizon
-	reducing conditions
-	stagnic colour pattern

0-1 cm	ochric horizon
35-90 cm	natric horizon
-	strongly humic
-	stagnic

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Silti-Stagnic Solonetz

Orthic Solonetz

0-1 cm	ochric A horizon
35-90 cm	natric B horizon
- cm	natric B horizon
- cm	ochric A horizon
-	stagnic

0-1 cm	ochric A horizon
35-90 cm	natric B horizon

Local classification:	Haplic solonetz; Hapli-Alkalic Halosol
Common name:	Black sodic soil

Other classification

USDA-SCS (1975)

Natriboralf ustic fine montmorillonitic frigid

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
1-14	-	0.1	0.1	0.2	1.1	24.1	25.6	27.0	15.6	42.6	31.9
17-30	-	0.0	0.1	0.3	0.8	21.4	22.6	25.1	15.9	41.0	36.4
40-60	-	0.0	0.0	0.1	0.3	16.1	16.5	29.9	13.9	43.8	39.8
65-85	-	0.0	0.1	0.1	0.3	13.4	13.9	27.3	19.2	46.5	39.7
100-140	-	0.0	0.0	0.1	0.2	9.1	9.4	27.6	23.3	50.9	39.7

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
5-10	1.046	-	-	-	-
1-14	-	-	-	9.3	31.9
20-25	1.299	-	-	-	-
17-30	-	-	-	27.4	36.4
45-50	1.320	-	-	-	-
40-60	-	-	-	37.9	39.8
65-85	-	-	-	39.7	39.7
100-140	-	-	-	27.3	39.7

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
5-10	1.046	54.3	51.8	47.6	39.2	35.9	31.7	26.5	20.2
20-25	1.299	49.4	49.4	49.4	49.3	48.9	47.6	36.8	32.4
45-50	1.320	53.2	53.2	53.2	53.1	52.9	50.4	38.5	31.3

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
1-14	8.7	7.2	0.46	1.1	3.06	0.32	10	-	-	39.1	3.5	0.3	5.8	48.7
17-30	9.6	7.8	0.94	2.8	2.04	0.24	9	0.1	0	44.0	4.9	0.2	16.2	65.3
40-60	10.0	8.2	1.10	6.1	0.78	0.09	9	0	0	37.0	7.7	0.3	21.0	66
65-85	9.9	8.3	1.00	8.5	0.44	0.05	9	0	0	35.3	9.9	0.1	16.8	62.1
100-140	9.6	8.0	0.66	7.8	0.35	0.04	9	0	0	39.9	11.2	0.1	9.1	60.3

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 %
1-14	154	31.7	99	10.7	-	-	18
17-30	223	29.3	80	7.1	-	0	55
40-60	-	24.3	61	2.7	-	0	86
65-85	-	21.9	55	1.5	-	0	77
100-140	-	19.2	48	1.2	-	0	47

Depth (cm)	CaSO4.2H2O %	P Bray mg/kg	P Olsen mg/kg	pH CaCl2	clay_noncarbonate % w/w	clay_carbonate % w/w	phosphorus4 mg/kg	phosphorus1 mg/kg	total_sulfur % w/w
1-14	-	-	2.1	-	-	-	-	-	-
17-30	-	-	3.4	-	-	-	-	-	-
40-60	-	-	1.3	-	-	-	-	-	-
65-85	-	-	0.4	-	-	-	-	-	-
100-140	-	-	1.2	-	-	-	-	-	-

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
1-14	weak	very weak	-	-	-	-	weak	weak	-	weak	strong	-
17-30	weak	very weak	-	-	-	-	weak	weak	-	weak	strong	-
40-60	weak	very weak	-	-	-	-	weak	weak	-	weak	strong	-
65-85	weak	weak	-	-	-	-	medium to strong	weak	-	weak	medium to strong	-
100-140	weak	weak	-	-	-	-	medium to strong	weak	-	weak	strong	-

Profile description

E 1-14 cm	very dark brown (7.5YR 2/2, moist)silt loam structureless,weakly coherent porous massive,slightly hard very friable sticky plastic,common very fine tubular pores,clear smooth boundary to,
Btn 14-35 cm	(7.5YR 2/3, moist)silty clay loam structureless,weak fine and medium prismatic parting to weak to moderate fine and medium angular blocky,very friable sticky plastic,common medium prominent sharp mottles (10YR 6/3),patchy thin clay and humus on pedfaces cutans,many very fine tubular pores and very fine continuous tubular pores,clear smooth boundary to,
BCt 35-60 cm	(7.5YR 3/3, moist)silty clay loam structureless,weak to moderate coarse subangular and angular blocky parting to moderate medium crumb,very friable sticky plastic,patchy thin clay and humus on pedfaces cutans,many very fine tubular pores and very fine continuous tubular pores,gradual smooth boundary to,
60-90 cm	(7.5YR 4/3, moist)silty clay loam structureless,moderate fine and medium crumb,very friable sticky plastic,common coarse prominent diffuse mottles (7.5YR 4/1),patchy thick clay and humus on pedfaces cutans,many very fine tubular pores,gradual smooth boundary to,
C 90-160 cm	light yellowish brown (10YR 6/4, moist)silty clay loam structureless,moderately coherent,very friable sticky plastic,few coarse prominent diffuse mottles (7.5YR 3/1),patchy thin clay and humus cutans,common very fine tubular pores,

Kind 1 (parent material) ; Parker (eds), 1984	sediment, unconsolidated
Mode of accumulation or deposition of parent material	lacustrine sediments
Remarks on Parent Materials	small snails shells
Soil Depth	60cm
Texture of parent material	clayey
Texture of parent material (second entry)	clayey

Occurrence of soil aggradation (McDonald et al., 1984)	absent
Intensity of the soil erosion type	severe
Intensity of the soil erosion type (second entry)	severe
Soil erosion type	wind
Soil erosion type (second entry)	sheet

Land use or vegetation in the immediate vicinity of the site	semi-natural grassland, grazed
Remarks on Land Use / Vegetation	VEGETATION: Alkali-tolerant grassland
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)	short grassland

Altitude	150m
Physiographic Unit	very flat plain
Physiographic position of the site	flat
Regional landform; McDonald, R.C., Isbell, R.F. et all, 1984; Australian soil and land survey Field Handbook, Inkata Press, Melbourne.	lacustrine plain
Slope	0%
Topography; Guidelines for soil description - Fourth edition (FAO, Rome, 2006)	flat or almost flat

Lower limit of a slow permeable or stagnating layer in the profile	35cm
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)	ponded
Upper limit of a slow permeable or stagnating layer in the profile	14cm

Evidence of alkali ; Soil Survey Manual USDA, 1951	moderately alkaline
Surface cracking	no cracks observed
Slaking of aggregates by tillage, rainfall or frost (USDA/SCS, 1979)	surface slaked; sorted sand/silt, some clay films
Rock outcrop class (FAO (2006) - Guidelines for soil description)	none
Evidence of salt; Soil Survey Manual USDA, 1951	slightly saline
Surface stoniness class (FAO (2006) - Guidelines for soil description)	none

You are here

Reference soil China 38: Solonetz

Characteristics

Reference soil CN038: Solonetz

Classification