Contents preface (VII) introduction 1—37

6.4.15. Soil Reclamation
Saline soils are found in the states of Madhya Pradesh, Rajasthan, Maharashtra, Karnataka, Andhra Pradesh, West Bengal, Tamil Nadu, and Gujarat. Alkaline soils are found in the Indo-Gangetic plains of Punjab, Haryana, UP, and parts of Bihar and Rajasthan. Because of their adverse effects on agricultural production as well as magnitude, saline and alkaline soils need to be reclaimed on a high priority basis and in a planned manner by the joint efforts of agricultural chemists, agronomists, agricultural experts, and irrigation engineers. The role of an irrigation engineer is important in lowering the water table if it is high and also providing irrigation water of good quality for leaching out the salts.
For reclamation works, one needs to know the following before taking any remedial measure (8):
(i) Characteristics of the soil and the salts present in it, (ii) Availability and quality of irrigation water,

(iii) Level of ground water table, and

(iv) Crops which can be grown under given conditions.

MANAGEMENT OF CANAL IRRIGATION IN INDIA

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The main components of soil reclamation works are as follows (8):

(i) Isolation of land areas according to their categorisation and levelling and bunding of the affected land as per the category.
(ii) Provision of drainage (surface or subsurface or vertical) network to remove leaching water and to keep the water table to a safer level.
(iii) Breaking up of impervious subsoil layer in alkali soils by deep ploughing.
(iv) Adding suitable chemicals (such as gypsum, sulphur, etc.) depending upon the re-sults of chemical tests of the affected soil.
After application of the chemicals, the leaching is carried out by four to five applications of good quality water up to depth of about 60 cm.
If the reclaimed soil is not suitable for foodgrain production, it can be used to grow certain species of trees such as safeda (hybrid eucalyptus), vilayati babul (prospis jiliflora), and indigenous babul (acacia milotica). If the soil has been reclaimed to the extent that it can be used for foodgrain production, it is usual to grow paddy as the first crop in Kharif and barley or wheat in the next Rabi and dhaincha in summer as a green manure.