Mapping groundwater recharge potential zones in arid region using remote sensing and GIS perspective, Central Tunisia

Given the semi-arid to arid climate in the Regueb region of Central Tunisia, groundwater is a crucial resource for meeting the escalating demands of socioeconomic development. Careful estimation of the current recharge amount and the delineation of potential zones of rainfall precipitation are required for an accurate evaluation of the regional water balance in order to ensure sustainable development and preserve water resources. The aim of this study was to define the prospective locations for phreatic aquifer recharge by doing a preliminary assessment of the groundwater recharge in the Regueb basin. In order to determine the lateral variation of the recharge zone, ArcGIS was utilized in conjunction with a geological and hydrogeological database that was acquired. The obtained results indicated that there are five recharge potential areas: 5% of the study area has very low, 9% has low, 20% has moderate, 28.5% has good, and 36.5% (located principally in the southern part of the study region) has very good recharge potential. This distribution is controlled principally by the geomorphological, geologic, and hydrogeological features of the region. Reasonable management strategies based on the perennial exploitation of these low-renewable resources are required to optimize water-dependent socio-economic development. The environmental risk from groundwater and/or soil pollution and salinization (total dissolved solids (TDS) in groundwater ranged between 1.19 and 16.92 g/L) is undoubtedly explained by the dual actions of climatic conditions and mismanagement of land resources, especially in the agricultural sector, as the study area is mainly devoted to irrigation of vegetation. In addition, this study is helpful in the establishing and managing sustainable groudwater. An isotopic analysis is recommended to aid the decision maker in establishing an adequate strategy.