Groundwater potential zones demarcation in the hard rock province of South India: insights from remote sensing, GIS and AHP techniques
摘要
The research aims to assess the groundwater potential zones (GWPZs) in the Chinnalapatti firka hard rock region to aid in sustainable groundwater management. The GWPZs were determined with the aid of Analytic Hierarchy Process (AHP) along with remote sensing (RS) and geographical information system (GIS) technologies. These Remote sensing and GIS greatly enhance groundwater potential mapping and assessment, as well as monitoring and conservation efforts. To evaluate groundwater potential (GWP) in the area of interest, remote sensing (RS) and conventional data sources were used to construct eight thematic maps. These maps included lineament density, drainage density, rainfall, geomorphology, geology, land use/land cover, soil and slope. Using AHP, each thematic layer, along with its subclasses, was assigned weights based on their influence on groundwater occurrence. Following this, the GWPZ map of Chinnalapatti firka was prepared by integrating the thematic layers with weighted overlay analysis in ArcGIS 10.7. The resulting map classified the study area into five groundwater potential groups: very good (19.97%), good (31.78%), moderate (30.61%), poor (17.63%), and very poor (0.01%). Utilizing the ArcSDM tool within ArcGIS software, the receiver operating characteristic (ROC) curve analysis showed that the area under the curve AUC = 0.80, which means that the GWPZ has good model performance. Planning and implementing artificial groundwater recharge projects, especially in semi-arid and hard rock terrains, is greatly aided by the spatial database created in this study. To improve groundwater sustainability, appropriate locations for recharge activities must be found. These results provide important information for sustainable groundwater management and long-term planning of water resources in the Chinnalapatti Firka region.