Chemistry Reference
In-Depth Information
Table
3
Some
chemical
characteristics
of
selected
sites
in
West
Africa.
(Source: Sy).
81
Organic
matter
(%)
Available P
(bray 1)
(mg kg
21
)
d
n
1
r
2
n
g
|
4
Soil
classification
Soil pH
(H
2
O)
CEC
(cmol kg
21
)
Site
Fendal (Liberia)
Plinthic Acrisol
1.5
5.0
1.0
6
Owem (Nigeria)
Acrisol
2.2
4.8
5.2
6
Kwadaso (Ghana)
Acrisol
1.3
4.9
3.5
2.2
Samaru (Nigeria)
Lixisol
1.0
5.8
4.3
3.5
Davie (Togo)
Nitisol
0.8
6.0
2.8
1.4
Kaboli (Togo)
Lixisol
1.1
5.9
2.4
1.2
Farakoba (Burkina
Faso)
Lixisol
1.0
5.4
0.8
2.7
Agonkamey (Benin)
Alfisol
0.6
6.6
2.3
2.0
Yundum (Gambia)
Lixic Ferralsol
1.1
5.5
8.1
15.2
Saria (Burkina Faso)
Arenosol
0.6
5.3
1.8
2.5
Gaya (Niger)
Arenosol
0.7
6.3
1.7
2.3
Sadore (Niger)
Aridic Arenosol
0.3
5.0
1.0
2.8
Sotuba (Mali)
Lixisol
0.5
5.4
2.3
1.7
elements in the process. Such improved methods of tillage should lessen the
problem of hardpans and plough soles. This will greatly enhance soil water
uptake for plant growth,
13
developing efficient systems of irrigation that
increase production without degrading the soil,
14
and adopting soil conserva-
tion measures that are simple, effective and affordable.
15
Thus, understanding
the soil is the key to its improvement as there are many physical, chemical and
biological properties of the various soil types that affect plant growth.
4 Soil Biology: Role of Soil Biodiversity and Functions
(Ecosystem Services)
Soil biota are an essential component of soil health and constitute a major
fraction of global terrestrial biodiversity.
16
Within the context of Integrated
Soil Fertility Management (ISFM), soil biota are responsible for the key
ecosystem functions of decomposition and nutrient cycling, soil organic matter
synthesis and mineralisation, soil structural modification and aggregate
stabilisation, nitrogen fixation, nutrient acquisition, regulation of atmospheric
composition, the production of plant growth substances and the biological
control of soil-borne pests and diseases.
17
Understanding biological processes
is not as well advanced as those that are related to soil physical and chemical
properties, creating opportunities for breakthroughs in biotic function to
better service agriculture. These services accrue through two basic approaches:
indirectly, as a result of promoting beneficial soil biological processes and
ecosystem
services
through
land
management,
or
directly
through
the
