Water Quality Monitoring for Irrigation by the Integration of Water Quality Index in a Geographic Information System Environment in Chiba Watershed, Nabeul, Tunisia

Irrigation is essential to ensure food security in arid and semi-regions and even in countries affected by water scarcity. Furthermore, monitoring water quality using appropriate water quality indicators can be a valuable approach in developing sustainable groundwater management strategies. Therefore, the aims of this study are to establish a Water Quality Index (WQI) for irrigation purposes and to predict groundwater appropriateness in Chiba watershed in Nabeul, Tunisia. The research methodology applied in this study integrates a comprehensive WQI calculation within a GIS framework to evaluate and forecast groundwater suitability for irrigation. In addition, the main parameters of this WQI are associated with the risk of the salinity problems, the reduction of water infiltration in the soil, and plant toxicity. The findings reveal that 84.38% of the analyzed samples present an average WQI value below 40, indicating severe restriction. However, only 3.12% of the samples are classified into low restriction class, with WQI values ranging between 70 and 85. The poor water quality observed is mainly attributed to both natural and anthropogenic factors. This study can be useful for decision-makers to adopt appropriate measures for water resource management and to mitigate the risks associated with crop toxicity, soil degradation, and yield loss.