TRADITIONAL IRRIGATION SYSTEM AND METHODS OF WATER HARVESTING IN THE OASIS OF SFISSIFA KSOUR MOUNTAINS - ALGERIA

Abstract

Groundwater serves as the most reliable source of water both for domestic use and for irrigation in arid zones, which are characterized by low rainfall and high evaporation. To overcome the water scarcity in these regions traditional water management systems were locally developed. This study was conducted on the oasis of Sfissifa, which is situated in the Wilaya of Naâma in the southwest of Algeria.  The main objectives of this study are to present the ancestral agricultural system of the region named “Tissfalt” and to assess the suitability of groundwater for drinking and irrigational purposes. The essential idea of Tissfalt is that of a gently sloping tunnel, often along the radius of an alluvial fan, which extends upslope until the water table is tapped and emerges at the downslope end to supply the oasis. It plays an important role in the social and economic development of the oasis. It’s considered also as a factor of stability enabling and regulating social interactions. Groundwater samples were collected and analyzed for major anions and cations. Physicochemical parameters such as electrical conductivity (EC) and total dissolved solids (TDS) were also measured. From the results of the analyses and measurements, the assessment of water potential for drinking uses was evaluated using physicochemical parameters, while the suitability for irrigation was evaluated based on the sodium adsorption ratio (SAR) and the percentage sodium (%Na), Wilcox diagram was also applied. The results show that all water samples analyzed fell within Algerian Standards’ guidelines limit, and also classify the groundwater as excellent for irrigation purposes.