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Sustainable agriculture can contribute to food security in arid and semi-arid regions if soil salinity in the root zone is kept under control. Recently, experts have been concentrating their research towrds alternative and environmentally friendly solutions. In this study, dry drainage was evaluated as a sustainable and cost-effective alternative technique, by means of both field experiments and a numeric approach based on the HYDRUS-2D modelling environment. Results showed that soil salinity in the cropped area increased from the soil surface to the bottom, and soil salinity movement (transport direction) was from the cropped to uncropped area. Increasing the ratio of cropped to uncropped width led to an increase in soil salinity of the cropped root zone and lack of stabilization of salinity concentration. Results of modelling showed that there are no significant differences between observed and modelled data, even though HYDRUS-2D simulated soil water content better than soil salinity. Averages of performance indices for simulated soil water content (SE = 0.08, NRMSE = 0.133) were better in comparison with simulated soil salinity (SE = 0.28, NRMSE = 0.262). Soil surface salinity in the cropped area increased 2.7 times (from 2.1 to 5.7 dS m(-1)) during the experiment for equal cropped to uncropped width (1 (cropped): 1 (uncropped)), and by increasing cropped width (2 (cropped): 1 (uncropped)) it increased 7.5 times (from 2.3 to 17.3 dS m(-1)). Copyright (c) 2017 John Wiley & Sons, Ltd.

Resume L'agriculture durable peut contribuer a la securite alimentaire dans les regions arides et semi-arides si la salinite du sol dans la zone racinaire est maitrisee. Recemment, les experts dirigent leurs recherches vers des solutions alternatives et respectueuses de l'environnement. Dans cette etude, le drainage evaporatoire a ete evalue comme une technique alternative durable et rentable, au moyen d'experiences de terrain et d'une approche numerique basee sur l'environnement de modelisation HYDRUS-2D. Les resultats ont montre que la salinite du sol dans la zone cultivee augmentait de la surface du sol vers le fond, et que les transferts de sels (direction du transport) se faisaient de la zone cultivee a la zone non cultivee. L'augmentation du rapport entre la largeur cultivee et la largeur non cultivee a entraine une augmentation de la salinite du sol de la zone racinaire et un defaut de stabilisation de la concentration en sels. Les resultats de la modelisation ont montre qu'il n'y avait pas de differences significatives entre les donnees observees et modelisees, meme si HYDRUS-2D simule mieux la teneur en eau du sol que sa salinite du sol. La moyenne des indices de performance pour la teneur simulee en eau du sol (SE = 0.08, NRMSE = 0.133) etait meilleure en comparaison de la salinite simulee du sol (SE = 0.28, NRMSE = 0.262). Lorsque le ratio largeur de la bande cultivee a celle de la bande non cultivee vaut 1, la salinite entre les deux bandes, la salinite de la surface du sol augmente de 2.7 fois d'une bande a l'autre (de 2.1 a 5.7 dS m(-1)); lorsque ce ratio vaut 2, la salinite du sol augmente de 7.5 fois (de 2.3 a 17.3 dS m(-1)). Copyright (c) 2017 John Wiley & Sons, Ltd.