Chikhaoui et al. (2026) Advancing groundwater recharge zone mapping using AHP and high-resolution satellite imagery: A case study from northwestern Tunisia

Identification

• Journal: Journal of African Earth Sciences
• Year: 2026
• Date: 2026-02-12
• Authors: Zied Chikhaoui, Rim Trabelsi, K. Zouari
• DOI: 10.1016/j.jafrearsci.2026.106076

Research Groups

Radio-Analysis & Environment Laboratory (LRAE), National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia

Short Summary

This study maps groundwater recharge potential in the El Kef region of northwestern Tunisia using an integrated approach combining remote sensing, geological/hydrogeological data, and the Analytical Hierarchy Process (AHP). It identifies that 42.8% of the area has high recharge potential, validated by multi-tracer analysis, providing a framework for sustainable groundwater management.

Objective

• To accurately identify and map groundwater recharge zones in the El Kef region of northwestern Tunisia for effective management, addressing the threat to groundwater resources in semi-arid regions.

Study Configuration

• Spatial Scale: El Kef region, northwestern Tunisia.
• Temporal Scale: Current (based on available data for mapping and validation).

Methodology and Data

• Models used: Analytical Hierarchy Process (AHP), weighted overlay analysis (in ArcGIS).
• Data sources: High-resolution satellite imagery (remote sensing), geological datasets, hydrogeological datasets, lithology, lineament density, ground slope, soil texture, precipitation, land use/land cover (LULC), drainage density, piezometric levels, well yields, tritium, δ2H, total dissolved solids, nitrate concentrations.

Main Results

• 42.8% of the study area exhibits high groundwater recharge potential, concentrated in zones with favorable lithology, permeable soils, and low-gradient topography.
• 35% of the area shows moderate recharge potential, and 22.2% has low potential, dominated by impermeable clay formations and steep slopes.
• Sensitivity analysis determined uncertainty envelopes: 38.2–43.5% (high), 33.7–39.5% (moderate), and 21.7–22.7% (low).
• Multi-tracer validation (piezometric levels, well yields, tritium, δ2H, total dissolved solids, nitrate concentrations) confirmed a strong correspondence between mapped high-recharge zones and areas of elevated groundwater productivity and recent recharge signatures.

Contributions

• Provides a spatially explicit framework for prioritizing groundwater management interventions, including artificial-recharge site selection and aquifer-protection strategies.
• Demonstrates an integrated approach combining remote sensing, geological/hydrogeological data, and AHP for mapping groundwater recharge potential in semi-arid regions.
• Offers direct applicability to other semi-arid regions worldwide facing similar groundwater-depletion pressures.

Funding

• Not specified in the provided text.

Citation

@article{Chikhaoui2026Advancing,
  author = {Chikhaoui, Zied and Trabelsi, Rim and Zouari, K.},
  title = {Advancing groundwater recharge zone mapping using AHP and high-resolution satellite imagery: A case study from northwestern Tunisia},
  journal = {Journal of African Earth Sciences},
  year = {2026},
  doi = {10.1016/j.jafrearsci.2026.106076},
  url = {https://doi.org/10.1016/j.jafrearsci.2026.106076}
}