The publication of this Handbook was supported by the Russian Federation

Soil leaching to remove salts. Soil leaching to remove salts is a treatment designed for reducing 
an excessively high concentration of  salts down to a level that permits the growth of  agricultural 
crops. The treatment involves supplying freshwater to the soil surface and collecting the drained 
saline solution [21]. Leaching treatments are applied to soils containing toxic salts of  alkali metals, 
alkaline earth metals and/or heavy metals with the aim of  detoxifying such soils.
Under agricultural crops the thickness of  a treated layer is usually around 1 m. This can be 
decreased to 0.5 m under highly and moderately salt-resistant crops with shallow root systems 

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Chapter 4.The rational use of saline and alkaline soils (with examples from Ukraine) 
(fodder beet, Sorghum sudanense and other sorghum varieties, cereal crops and some vegetable crops), 
if  the soil layer below that depth is only weakly saline.
Flooding is the main and most widespread technique of  soil leaching. An optimal time period for 
flooding is September-October, when the groundwater table is deep and evaporation is low. At 
that time, leaching treatment also serves as soil irrigation. Preparation for leaching includes soil 
ploughing, levelling, repeat ploughing, application of  calcium-containing ameliorators, harrowing 
and the creation of  ridges to prevent run-off.
The method of  saline soil leaching using sprinkler irrigation was developed and implemented 
by specialists from the Institute for Soil Science and Agrochemistry Research named after O.N. 
Sokolovsky (Kharkiv). Soil pre-treatment before sprinkling includes leaching by flood irrigation 
without the construction of  dividing ridges on the field surface. Sprinkling devices of  any type can 
be used if  they provide uniform moistening of  soils together with water supply rates of  up to 3-4 
thousand m
3
 / ha for a period of  several days [14].
On weakly saline soils and also in cases, where residual salinity is retained after leaching treatments, 
sprinkler irrigation rates are lower. These are undertaken either in spring (at the beginning of  the 
growing season) or in autumn (as a moisture-recharge treatment to support winter crops).
Leaching of  saline soils by sprinkler irrigation in combination with vertical drainage systems and 
chemical amelioration treatments are 10 times cheaper and require 4-5 times less water, than 
traditional leaching by flooding. The rates of  soil desalinization and yield increases are the same 
in both cases.