QUANTIFICATION DE LA DOSE DE LESSIVAGE ET PERFORMANCE DU RESEAU DE DRAINAGE DANS LE PERIMETRE IRRIGUE DE KALAAT EL ANDALOUS (TUNISIE)

Abstract

In Tunisia, saline soils occupy an area of 1,5 million hectares, roughly 25% of the total area of arable land in the country. The irrigated area of Kalâat EL Andalous, is a part of this environment and already characterized by low yields. The present work aims to quantify the dose of salt leaching and verification of its effectiveness to predict the risk of salinity on the soil and on plants. The measured of leaching dose is about 1100 m³/ha, close to the theoretical value determined by the formula of Rhoades. A quantity of salts made by the irrigation water is about 15 t / ha, the amount of leached salt is about 9 t / ha. The amounts of salt accumulated in the root zone during the irrigation season is 6 t / ha.