GEOINFORMATICS-BASED APPROACH FOR AQUIFER RECHARGE ZONE IDENTIFICATION IN THE WESTERN DESERT OF IRAQ
Keywords:
GIS, RS, GWPZs, AHP, Multi-Criteria decision makingAbstract
Vast parts of the globe are facing a water scarcity problem owing to the increasing water demand of the growing population and urban expansion, and intensive agriculture and industrial activities. Arid and semiarid areas already suffer from a severe shortage of surface water supplies due to climatic conditions such as a temperature rise, evaporation rates, and diminution of rainfall amounts with discontinued intervals. Delineation of suitable sites for the groundwater potential recharging zones is one of the available solutions to recompense surface water shortages in the Al-Mohammedi basin in the Iraqi Western Desert. Recently, the utilization of modern geospatial techniques such as remote sensing (RS) data and geographic information system (GIS) in combination with multi-criteria decision-making (MCDM) approaches has proven an efficient tool for groundwater demarcation. In this study, RS data, such as Landsat 8 images and SRTM Digital Elevation Model (DEM), published geological maps, and metrological data were used to generate eight thematic layers of criteria—geomorphology, geology, lineament, rainfall, soil infiltration, slope, land use and land cover, and drainage density. All thematic maps were generated and transformed into the raster format depending on the raster conversion tool in ArcGIS 10.8 software. The output map of groundwater potential zones (GWPZs) was generated by integrating all the thematic layers according to the weightage values generated depending on the Analytical Hierarchal Process (AHP) approach. Finally, the prospective zones were examined and validated with present yield wells data. Twenty-two out of twenty-eight validation boreholes (76.87%) matched the predicted classes of the yield boreholes, and the cross-correlation value certified this result as R2 = 0.67.