Full Paper [PDF] - Ahmadu Bello University

Nig. J. Soil & Env. Res. Vol. 11: 2013, 86 - 93
@ Department of Soil Science,
Faculty of Agriculture,
Ahmadu Bello University, Zaria,
Nigeria
Nigeria
Journal of Soil and
Environmental Research
Classification and properties of soils developed on gneisses and schists
in the Northern Guinea Savanna of Nigeria
1
Shobayo, A.B., 2Raji, B.A., 1Malgwi, W.B. and 1Odunze, A.C.
1
2
Department of Soil Science, Ahmadu Bello University, P.M.B. 1044, Zaria, Nigeria.
Fountain University, Osogbo, P.M.B. 4491, Osogbo, Osun State, Nigeria.
ABSTRACT
The sustainable use of soil resources requires in depth knowledge of the soil forming factors and
processes influencing soil development. The present study evaluates the morphological, physical and
chemical properties of soils developed on two parent materials (gneiss and schist). The geology of the
study area indicated that soil parent materials were primarily of Basement Complex. Three pedons were
examined in each type of parent material. The six pedons were located on the crests of the landscapes and
sampled to determine the soil parent material differences. Particle size distribution and some
selectedchemical analyses of the soils studied indicated that the soils were well stratified. All the soils
were deep to moderately shallow. Values of clay content (80 to 400 gkg-1) increased with depth except in
the Btv horizons across the six pedons. Blocky structure dominated in the soils developed in both types
ofparent materials. CEC values of soils formed on gneiss and schist were rated medium [4.2 to 15.2
cmol(+)kg-1]. Soils of the study area were classified based on the criteria and nomenclature of USDA
Soil Taxonomy and correlated with the World Reference Base for Soil Resources (WRB). The soils were
mostly plinthustalf or Eutric Lixisols.
Keywords: Lithosequence, parent material, basement complex.
INTRODUCTION
Soils are resources that affect the wealth of nations.
This study focused on the effect of parent material on the
formation of soils in Zaria area. Geology of the area is
Basement Complex. Basement complex rocks are the
oldest rocks in Nigeria and they are made up of granites,
quartzites, schists, and gneisses (Iloeje, 2004). In this
study, two different parent materials, gneiss and schist
were chosen. It has been reported that Basement Complex
(senile parent material) has less influence on soil
formation over time or space compared to the juvenile
parent materials (Esu, 1999). This study on lithosequence
is aimed at confirming this fact on soils of Zaria
environment. Buol et al. (1981) reported that the influence
of any soil forming factor on soil properties can be made
only within specified geographic areas. This, they say, is
due to spatial variation in parent materials and other soil
forming factors.
Effect of the composition of soil parent materials
on pedogenic processes has long been recognized
(Ehrlich et al., 1955; Akamigbo and Asadu, 1983).
Different soils will result from different types of parent
material or lithosequences of soils. Adjacent soils
frequently exhibit different profile characteristics because
of differing parent materials. These differing soil areas are
called lithosequences (Esu, 1999). Thus, understanding
the influence of parent material on the morphological and
chemical properties of the soils formed on the Basement
Complex of Zaria area is needed to complement the
present knowledge of soil forming processes in the study
area.
Objectives of this study were:
1.
2.
To determine the variation in morphological and
physicochemical properties and assess the status of
the soils developed on the two parent materials.
To classify the soils formed on two parent materials
(gneiss and schist) according to the USDA Soil
Taxonomy (Soil Survey Staff, 1999) and the World
Reference Base for Soil Resources (FAO-ISRICISSS, 1998).
Shobayo, A.B., Raji, B.A., Malgwi, W.B. and Odunze, A.C.
89
33 57
57 100
Bt2
Btv
62 80
Btv
28 59
Btv
12 58
58 96
96 182
Bt1
Bt2
Btv
0 12
Ap
Pedon SIII
0 14
14 28
Ap
Bt
1.67
1.38
1.62
1.44
1.48
1.54
1.68
1.80
47 105
Pedon SII
Bt2
1.64
0 13
13 47
Ap
1.41
1.54
1.47
1.57
1.60
1.56
1.36
1.82
Bt1
Pedon SI
13 30
30 62
Bt1
Bt2
0 13
Ap
Pedon GIII
0 14
14 33
Ap
Bt1
1.39
1.47
41 160
Pedon GII
Bt2
1.47
0 12
12 41
1.53
BD
(Mgm-3)
Ap
Depth
(cm)
Bt1
Pedon GI
Horizon
320
30
0
0
660
430
100
140
110
420
610
420
140
130
590
140
50
110
40
40
20
Gravel*
(gkg-1)
Table 2: Physico-chemical properties of soils
440
400
360
700
580
560
680
360
520
600
500
440
460
660
580
340
400
540
340
380
580
Sand
(gkg-1)
240
280
240
220
180
220
260
240
240
300
220
240
240
260
200
300
280
320
280
260
300
Silt
(gkg-1)
H20
pH 1:2.5
5.0
5.5
5.1
4.5
5.1
4.8
4.5
4.6
5.0
4.8
4.7
320
320
400
80
240
220
60
400
240
100
5.1
5.3
5.0
5.6
5.8
5.3
5.8
5.3
4.9
5.4
Schist Parent material
280
320
300
80
220
360
320
140
380
360
120
Gneiss Parent Material
Clay
(gkg-1)
3.7
4.4
4.3
4.4
5.2
4.4
5.0
4.9
4.3
5.1
5.3
4.5
4.3
4.3
4.0
3.8
3.8
4.1
3.6
3.9
3.8
CaCl2
2.17
2.33
2.03
1.83
3.67
1.83
1.83
6.67
3.50
1.67
4.00
4.33
2.83
1.83
1.67
3.20
2.50
2.50
2.17
1.50
1.50
Ca
1.75
2.16
2.82
1.33
2.72
1.45
1.17
5.54
3.07
1.15
2.12
2.40
2.00
1.19
2.22
2.40
1.75
1.15
1.85
0.85
0.63
Mg
0.03
0.04
0.17
0.26
0.18
0.06
0.21
0.10
0.17
0.17
0.61
0.19
0.45
0.17
0.17
0.61
0.52
0.17
0.16
0.21
0.10
Na
0.14
0.06
0.07
0.13
0.04
0.05
0.04
0.26
0.04
0.08
0.13
0.04
0.03
0.07
0.07
0.24
0.17
0.26
0.17
0.04
0.09
K
Exchangeable Bases [cmol(+)kg-1]
4.09
4.59
5.09
3.55
6.61
3.39
3.25
12.6
6.78
3.07
6.86
6.96
5.31
3.26
4.13
6.45
4.94
4.08
4.35
2.60
3.32
Total
4.6
1.8
1.8
0.6
0.4
0.8
0.4
0.8
0.8
0.6
0.8
1.8
1.2
1.0
0.8
2.8
2.4
1.6
2.8
2.6
1.0
Exch. Acidity
(H++Al3+)
(cmolkg-1)
90
Classification and properties of soils developed on gneisses and schists in the Northern Guinea Savanna of Nigeria

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