Reference soil Mali 05: Fluvisol

ML005

Fluvisols typically are young soils in alluvial, deltaic, lacustrine, or marine deposits, and occur all over the world.

Characteristics

Soils having fluvic soil material starting within 25 cm from the soil surface and continuing to a depth of at least 50 cm from the soil surface. They have no diagnostic horizons other than a histic, mollic, ochric, takyric, umbric, yermic, salic, or sulfuric horizon.

Distribution of Fluvisols (rough estimation supplied by soilgrids)

Reference soil ML005: Fluvisols

See also data from unit X1 in"Mali land and water resources", 1983, PIRT, mapscale 1:500.000. Oral information indicates that the lake was yearly flooded by the Niger. The flooding stopped due to the blocking of the entrance/outlet by sand dunes. The soil has a very low bulk density. Structure of the Ah horizon is powdery. Porosity is difficult to assess, infact a high micro porosity is present. Effective soil depth is probably limited by platy structure of the subsoil. Texture is probably silt (the soil brought into suspension settles quickly). When the ferro-oxyde mottling is not fossile but caused by stagnant water,the soil will classify as an aquic torriorthent. Monthly precipitation records of the period 1907 to 1985 are available in the file. The windspeed is recorded at a height of 10 meter. Vegetation changes has been monitored by PIRT for the period 1980-1986.

Classification

WRB 2006

WRB 1998

Gleyic- Fluvisol (Calcaric Sodic Aridic Siltic)

Aridi-Gleyic- Fluvisol (Calcaric Endosodic)

FAO-UNESCO-ISRIC 1988

FAO-UNESCO-ISRIC 1974

Sodi-Calcaric Fluvisol

Calcaric Fluvisol sodic

0-14 cm	ochric A horizon
-	calcareous
-	sodic

0-14 cm

ochric A horizon

Local classification:	Lacs desseches *

Other classification

USDA-NRCS (1999)	Typic Torrifluvent
USDA-SCS (1975)	Typic Torrifluvent aridic fine-silty mixed (calcareous) hyperthermic

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
0-14	-	1.4	1.2	1.3	5.3	4.0	13.2	13.9	47.7	61.6	25.3
14-32	-	0.6	0.5	0.5	1.8	1.6	5	12.2	57.9	70.1	24.9
60-80	-	0.8	2.2	2.4	4.1	1.7	11.2	8.0	45.3	53.3	35.5
80-125	-	0.1	0.2	0.4	1.1	0.7	2.5	1.9	41.0	42.9	54.7
125-160	-	0.5	0.6	1.4	7.5	6.2	16.2	2.8	34.7	37.5	46.2
160-180	-	0.0	0.1	0.1	0.8	1.2	2.2	9.2	53.0	62.2	35.5
180-200	-	2.2	2.8	2.9	5.9	5.3	19.1	8.2	34.0	42.2	38.8

Water retention characteristics

Depth (cm)	Bulk density kg/dm³	Spec. Surf. Area m²/g	COLE cm/cm	Water disp. clay %	Clay % w/w
7-12	0.66	-	-	-	-
0-14	-	-	-	13.8	25.3
100-105	0.54	-	-	-	-
14-32	-	-	-	14.8	24.9
60-80	-	-	-	24.5	35.5
80-125	-	-	-	29.3	54.7
125-160	-	-	-	20.2	46.2
160-180	-	-	-	23.3	35.5
180-200	-	-	-	27.7	38.8

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
7-12	0.66	71.8	68.3	63.4	55.8	52.0	45.7	22.2	17.1
100-105	0.54	77.5	76.0	68.8	63.8	61.6	57.7	31.2	25.3

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
0-14	8.3	7.1	0.25	14.3	1.22	0.13	9	-	-	57.2	4.1	4.0	0.1	65.4
14-32	8.3	7.0	0.26	13.8	1.29	0.13	10	-	-	51.0	4.8	2.5	0.2	58.5
60-80	8.3	6.9	0.27	5.0	0.85	0.12	7	-	-	46.3	8.4	2.9	1.1	58.7
80-125	8.6	7.0	0.30	3.5	0.91	0.14	7	-	-	23.3	6.3	3.6	3.0	36.2
125-160	8.8	7.0	0.35	3.5	0.75	0.12	6	-	-	28.5	6.5	3.7	3.8	42.5
160-180	8.9	7.4	0.34	55.6	0.62	0.06	10	-	-	46.5	8.2	1.8	2.5	59
180-200	9.1	7.2	0.34	30.7	0.74	0.08	9	-	-	51.7	8.1	7.1	5.2	72.1

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 %
0-14	330	19.8	78	4.3	-	-	1
14-32	291	20.1	81	4.5	-	-	1
60-80	152	38.5	108	3.0	-	-	3
80-125	137	26.4	48	3.2	-	-	11
125-160	168	25.3	55	2.6	-	-	15
160-180	391	15.1	43	2.2	-	-	17
180-200	241	29.9	77	2.6	-	-	17

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
0-14	-	-	-	0.1	0.1	0.4	0.0	-	-	-	0.1
14-32	-	-	-	0.1	0.1	0.6	0.1	-	-	-	0.1
60-80	-	-	-	0.0	0.4	6.1	0.0	-	-	-	2.5
80-125	-	-	-	0.1	0.1	1.9	0.1	-	-	-	0.3
125-160	-	-	-	0.1	0.1	1.5	0.1	-	-	-	0.1
160-180	-	-	-	0.0	0.2	4.1	0.0	-	-	-	0.9
180-200	-	-	-	0.2	0.1	0.5	0.0	-	-	-	0.2

Clay mineralogy

Depth (cm)	Chlorite	Feldspar	Gibbsite	Goethite	Halloysite	Hematite	Kaolinite	Mica / illite	Mixed-layer	Quartz	Smec	Vermiculite
0-14	-	-	-	-	-	-	weak	very weak to weak	weak to medium	-	very weak to weak	-
14-32	-	very weak to weak	-	-	-	-	weak to medium	weak	weak to medium	-	weak	-
60-80	-	very weak to weak	-	-	-	-	medium to strong	weak	weak	-	medium to strong	-
80-125	-	very weak to weak	-	-	-	-	strong	weak	weak	-	medium to strong	-
125-160	-	very weak to weak	-	-	-	-	strong	weak	weak	-	strong	-
160-180	-	very weak to weak	-	-	-	-	weak	-	very weak to weak	-	weak to medium	-
180-200	-	very weak to weak	-	-	-	-	weak to medium	weak	weak	-	weak to medium	-

Profile description

Ah 0-14 cm	greyish brown (10YR 5/2, moist)silt,single grain,soft slightly sticky slightly plastic,many very fine roots,strongly calcareous (10-25%),gradual smooth boundary to,
AC 14-35 cm	light olive grey (5Y 6/2, moist)silt,weak to moderate medium subangular blocky parting to weak very fine crumb,slightly hard slightly sticky slightly plastic,many very fine roots,strongly calcareous (10-25%),clear smooth boundary to,
CA 35-60 cm	light olive grey (5Y 6/2, moist)silt,moderate medium granular,slightly hard slightly sticky slightly plastic,many (15-40%) coarse prominent sharp mottles (5YR 4/4),few fine roots,moderately calcareous (2-10%),clear wavy boundary to,
C 60-85 cm	olive (5Y 5/3, moist)silt,strong fine platy,hard slightly sticky slightly plastic,moderately calcareous (2-10%),clear wavy boundary to,
Cg1 85-125 cm	(5Y 4.5/3, moist)silt,moderate fine and medium platy parting to moderate medium granular,slightly hard slightly sticky slightly plastic,few (2-5%) medium faint clear mottles (7.5YR 5/6),moderately calcareous (2-10%),gradual smooth boundary to,
Cg2 125-180 cm	light olive grey (5Y 6/2, moist)silt,massive,very hard slightly sticky slightly plastic,many (15-40%) coarse prominent sharp mottles (7.5YR 4/6),extremely calcareous (>25%),

Kind 1 (parent material) ; Parker (eds), 1984	sediment, unconsolidated
Mode of accumulation or deposition of parent material	lacustrine sediments
Remarks on Parent Materials	diatomitic sediments
Soil Depth	60cm
Texture of parent material	silty

Occurrence of soil aggradation (McDonald et al., 1984)	absent
Slope stability	stable

Land use or vegetation in the immediate vicinity of the site	semi-natural grassland, grazed
Remarks on Land Use / Vegetation	VEGETATION: "steppe a epineux xeromorphic"
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	260m
Physiographic Unit	lake bottom, no subdivision
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%
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
Dry From - To	0-200cm
Flooding frequency (FAO, 1986)	never
Kind of ground water table (USDA, 1979)	no groundwater table observed
Estimated permeability (class) of least permeable part of the profile	moderate
Estimated run off (class)	slow
Drainage class - intergrade; FAO (2006) - Guidelines for soil description	well

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 Mali 05: Fluvisol

Characteristics

Reference soil ML005: Fluvisols

Classification