A GIS mapping assessment of the suitability of the Oued Rmel aquifer for irrigation in the Zaghouan district (north-eastern Tunisia)

• Published in: Environmental earth sciences Vol. 77; no. 7; pp. 1 - 15
• Main Authors: Ameur, Meriem, Hamzaoui-Azaza, Fadoua, Ben Cheikha, Lilia, Ahmed, Toqeer, Gueddari, Moncef
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2018; Springer Nature B.V
• Subjects: adsorption; Alkalinity; alkalinization; Aquifers; bicarbonates; Biogeosciences; Calcium; Calcium ions; Carbonates; chlorides; Destabilization; Earth and Environmental Science; Earth Sciences; Electrical conductivity; Electrical resistivity; Environmental Science and Engineering; Geochemistry; geographic information systems; Geographical information systems; Geology; Groundwater; Groundwater quality; Hazards; Hydrology/Water Resources; ions; Irrigation; Irrigation water; Magnesium; Major elements; Original Article; Parameters; Permeability; potassium; Quality assessment; risk; salinity; SAR (radar); sodicity; Sodium; Sodium carbonate; Soil; Soil permeability; Spatial distribution; sulfates; temperature; Terrestrial Pollution; Tunisia; Water analysis; Water quality; Water quality assessments; Water sampling; winter; Tunisia; GIS; Water quality for irrigation; Oued Rmel aquifer; Tunisia; Water resources
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-018-7472-9

A total of twenty-three water samples were collected in winter 2013 to assess groundwater quality in the Oued Rmel aquifer in the Zaghouan governate in Tunisia. These samples were subject to in-field measurements of some physico-chemical parameters (temperature, pH, and salinity), and laboratory analysis of major elements. Several parameters were used to assess the quality of water destined for irrigation, including electrical conductivity (EC) and sodium adsorption ratio (SAR). As part of this work, GIS was used to study spatial distributions of SAR, EC, residual sodium carbonate, sodium percentage (%Na), Doneen’s permeability index, Kelly’s ratio, and magnesium hazard and, therefore, evaluated the water quality of Oued Rmel (good, fair, or poor) regarding irrigation. The major ions most abundantly found in the waters of Oued Rmel were in the following order: Na +  > Ca 2+  > Mg 2+  > K + and Cl −  > SO 4 2−  > HCO 3 . 56% of water samples from the Oued Rmel aquifer showed a low alkalinization risk, where SAR was lower than 10, 39% have a medium soil destabilization risks (10 < SAR < 18), and just 5% indicated high alkalinity hazards (SAR > 26). Samples of water intended for irrigation showed a medium to high sodicity and alkalinization risk. It is expected that output may help in assessing the impacts of water quality of the Oued Rmel aquifer used for irrigation.