Sodization, a threat to coastal irrigated areas case of M'nasra (Morocco)Author(s): I.Idrissi Alami, A.Rhidouani, M.Zeraouli, A.Haidar, A.Echchelh, M.Addou
The MÂnasra zone which has an agricultural land area that represents 70% of the total area and its agricultural production reach 12% of the national production is threatened by a sodization of underground waters. We know that this water table is the only ground water source available for this region. Thereby, researches that have been carried out on the field have confirmed the salinization of this water-table due to sea water intrusion and to intensive fertilization (salts) and pesticides. Sodium (Na+) is one of the most undesirable elements in irrigation water because of its negative effects and even toxic effects on sensitive crops of the region such as carrots, beans, strawberries etc. In this view, this work aims to study the spatial and temporal evolution of sodiumabsorption ratio (SAR), according to campaign period of 1993 and 2008 and in different places of MÂnasra region. The spatial analysis has confirmed a sodization of an area of 19,800 Ha representing 37%of the total area, between 1993 and 2008. The conformity of sodiumconcentration is compared toMoroccan and Canadian standards.