Chemistry Reference
In-Depth Information
Occurrence, characteristics, use and management of major soil types of the tropical region (Source: Palm et al.).
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Table 1
Constraints
Occurrence
Characteristics
Use and management
Soil types*
Soils with
salinity
problem.
Mainly in arid and
semi-arid areas, on
flat to very gently
undulating
topography and in
poorly managed
irrigation areas;
surface and ground
water may be the
main source of
soluble salts when
used for irrigation;
nature of the
parent material can
also be the source
of soluble salts.
A saline soil profile has a pH
below 8.5; white salt
crystals are common on the
sides of the soil profile or
salt crust can be seen on
the surface.
Can be reclaimed by leaching
excessive soluble salts.
Sometimes may be advisable to
leave the soils under natural
vegetation as it can be very
expensive to reclaim them
especially where availability of
good quality water for irrigation
is a limitation. Widely used for
growing horticultural crops in
small-scale irrigation schemes.
However, salt accumulation in
most of these schemes has led to
their abandonment. This is
because such soils require major
land improvement and thus
become extremely difficult to
manage under low-input
conditions which characterise
African small-scale farmers.
Solonchaks (saline soils) or
other soils classified as
having a saline phase.
