Modelling the effects of saline water use in agriculture

✍ Scribed by M. J. Kaledhonkar; Ashok K. Keshari

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 148 KB
• Volume: 55
• Category: Article
• ISSN: 1531-0353
• DOI: 10.1002/ird.226

✦ Synopsis

Abstract

Use of saline groundwaters is inevitable in rice–wheat, cotton–wheat, and millet–wheat crop rotations in the northern region of India due to limited canal water supplies. The UNSATCHEM model is calibrated and validated with field data on saline water use for the wheat and cotton crop. The calibrated and validated model has been employed to study different aspects of the salinisation process. The effect of irrigation water quality on the salinisation process is understood with the help of simulations in which irrigation waters of different SAR, SO and Cl^−^ concentrations are used. A linear relation is observed between the weighted average of irrigation water salinity and the root zone. The salinisation process under different conjunctive use practices is understood through simulations. The practices are compared on the basis of temporal changes in root zone salinity with reference to the sensitivity of the wheat crop to salinity for deciding the preference of one conjunctive use practice over another. The preference order, thus prepared, is verified with the published yield data of wheat from conjunctive use field studies. The effect of soil texture on salinisation is studied through simulations. The saturated water content influences the salinisation process more than the hydraulic conductivity. The long‐term simulations as per water quality guidelines for a six‐year period under wheat–cotton rotation are carried out to assess the sustainability of saline water use for crop production. Copyright © 2006 John Wiley & Sons, Ltd.