Farchouni et al. (2025) Mapping groundwater recharge potential zones in a semi-arid, anthropogenically modified mountainous basin

Identification

• Journal: Scientific African
• Year: 2025
• Date: 2025-10-07
• Authors: Abderrahman El Farchouni, Abdessamad Hadri, Younes Fakır, Mohamed Ouarani, Mohamed Azaroual, Azzouz Kchikach
• DOI: 10.1016/j.sciaf.2025.e03025

Research Groups

• International Water Research Institute (IWRI), Mohammed VI Polytechnic University, Ben Guerir, Morocco
• Center for Remote Sensing Application (CRSA), Mohammed VI Polytechnic University, Ben Guerir, Morocco
• Department of Geology, Faculty of Sciences Semlalia, Cadi Ayyad University, Marrakech, Morocco
• BRGM (French Geological Survey), France
• Geology and Sustainable Mining Institute (GSMI), Mohammed VI Polytechnic University, Morocco
• Georessources, Geoenvironment & Civil Engineering, Cadi Ayyad University, Morocco

Short Summary

This study maps groundwater recharge potential zones (GRPZ) in the semi-arid Tensift basin, Morocco, using a multi-factorial approach combining remote sensing, GIS, Analytical Hierarchy Process (AHP), and stable isotopes for validation. It identifies mountains and piedmonts as primary recharge areas, with moderate potential in irrigated plains and low potential in urbanized zones.

Objective

• To delineate Groundwater Recharge Potential Zones (GRPZ) in the semi-arid, anthropogenically modified Tensift basin, Morocco, by integrating a multi-factorial approach (rainfall, LULC, lithology, lineament density, slope, drainage density) with remote sensing, GIS, and AHP, and validating the results using stable isotopes (δ¹⁸O and δ²H).

Study Configuration

• Spatial Scale: Tensift basin, Morocco, approximately 22,000 square kilometers (km²), including the Haouz plain (approximately 6,500 km²), High-Atlas mountains, and Jebilet massif.
• Temporal Scale: Precipitation data analyzed for the period 1980–2022 (42 years).

Methodology and Data

• Models used:
  • Analytical Hierarchy Process (AHP) for assigning weights to recharge factors.
  • Random Forest (RF) classifier for Land Use and Land Cover (LULC) mapping.
  • Inverse Distance Weighting (IDW) for precipitation interpolation.
  • Geographic Information System (GIS) for spatial data integration and weighted overlay analysis.
  • LINE algorithm in PCI GEOMATICA software for automatic lineament extraction.
• Data sources:
  • Satellite imagery: Sentinel 2 (for LULC), Landsat 8 OLI (for lineament density).
  • Observation data: ASTER Digital Terrain Model (DEM) database (for slope and drainage density).
  • Reanalysis data: TerraClimate precipitation data (1980–2022).
  • Geological maps: Marrakech (1:500,000) and Oriental Haouz (for lithology).
  • Field samples: Groundwater samples for stable isotopes (δ¹⁸O and δ²H) from existing literature [2,4].

Main Results

• The GRPZ map categorizes the study area into five potential zones: Very Low, Low, Moderate, High, and Very High.
• Moderate recharge zones are the most extensive, covering 82.5 % (17,832.7 km²) of the basin, primarily in the plains.
• High recharge zones constitute 7.6 % (1,636.1 km²), predominantly located in the High-Atlas mountains and piedmonts, attributed to high precipitation, seasonal snowmelt, and streamflow.
• Low recharge zones account for 9.8 % (2,126.7 km²), mainly found in the arid Paleozoic massif of Jebilet and urban areas.
• Land Use and Land Cover (LULC) was identified as a pivotal factor, reflecting the significant impact of human activities like irrigation and urbanization on recharge patterns.
• Stable isotope validation (δ¹⁸O and δ²H) confirmed that groundwater recharge primarily originates from high-altitude precipitation in the High Atlas Mountains, with inferred recharge elevations between 1,800 and 2,800 meters above sea level (m.a.s.l.).
• Isotopic mass balance indicated that approximately 57 % of groundwater recharge in the Haouz plain originates from snowmelt, and 43 % from direct rainfall.

Contributions

• Develops a transferable and robust framework for mapping GRPZ in semi-arid, anthropogenically modified mountainous basins by integrating remote sensing, GIS, AHP, and stable isotope validation.
• Emphasizes the critical importance of Land Use and Land Cover (LULC) as a key recharge factor in such complex environments, accounting for urbanization, irrigation, and surface water bodies.
• Provides a process-based validation approach using environmental tracers (stable isotopes), which is more appropriate for data-scarce and complex basins than traditional well-based methods.
• Offers valuable insights for guiding sustainable groundwater resource management and Managed Aquifer Recharge (MAR) strategies, contributing to climate resilience and the achievement of Sustainable Development Goals (SDGs 1, 2, 6, and 13).

Funding

No specific funding projects, programs, or reference codes were provided in the article.

Citation

@article{Farchouni2025Mapping,
  author = {Farchouni, Abderrahman El and Hadri, Abdessamad and Fakır, Younes and Ouarani, Mohamed and Azaroual, Mohamed and Kchikach, Azzouz},
  title = {Mapping groundwater recharge potential zones in a semi-arid, anthropogenically modified mountainous basin},
  journal = {Scientific African},
  year = {2025},
  doi = {10.1016/j.sciaf.2025.e03025},
  url = {https://doi.org/10.1016/j.sciaf.2025.e03025}
}