Management of Salt-Affected Soils - Practices of Irrigation and On-farm Water Management - page 312

Land leveling is needed to achieve a more uniform application of water for
better leaching and salinity control. Tillage is useful for soil permeability improve-
ment. Deep tillage is most beneficial on stratified soils having impermeable layer.
It loosens the soil aggregates, improves the physical condition of the layer, and
increases air spaces and hydraulic conductivity. Special planting procedures that
minimize salt accumulation around the seed include planting on sloping beds or
raised furrows in single or double rows, which are helpful in getting better stands
under saline conditions.
Organic Manuring
Incorporation of organic manure in the soil has two principal beneficial effects on
saline soil: improvement of soil permeability and release of carbon dioxide and
certain organic acids during decomposition. It also acts as a source of nutrients.
Application of Sand (Sanding)
For fine textured soils, sand may be added to the surface soil to increase permeabil-
ity. As a result of such application, soil texture is permanently changed. If properly
done, sanding can result in improved air and water movement, and enhance leaching
by saline/sodic water. Sanding with plowing provides better results.
Row/Seed Bed Management
In addition to leaching salt below the root zone, salts can also be moved to areas
away from the primary root zone with certain crop bedding and surface irriga-
tion systems. The goal is to ensure the zones of salt accumulation stay away from
germinating seeds and plant roots.
In ridge bed system, salts accumulate at the center of the bed, and the shoulders
and corners are relatively salt-free (Fig. 8.5 ) , thus seedling establishment and plant
stand are better at the corner and sloping beds or shoulders compared to normal
planting.
Fig. 8.5 Arrangement of
row/seed bed for salinity
management