Remote sensing, GIS and AHP techniques based investigation of groundwater potential zones in the Karumeniyar river basin, Tamil Nadu, southern India

摘要

A primary objective of this study is to analyse the multiple parameters for mapping of groundwater potential zones in the Karumeniyar river basin located in Southern India using integrated remote sensing, GIS, and geophysical techniques. In this analysis, multiple geo-environmental parameters such as geology, geomorphology, soil, drainage density, lineament density, land use/land cover (LULC), slope, rainfall, topographic wetness index (TWI), surface roughness, topographic curvature, elevation (relief), and land surface temperature (LST) are analysed for identifying groundwater potentiality at site-specific scale using the GIS-based analytical hierarchy process (AHP) technique. Each thematic layer is derived from corresponding spatial data sources through systematic procedures and assigned to appropriate weights and ratings based on the degree of magnitude to recharge and permeability. The result reveals that 10.7 of the total area shows higher potential of groundwater sources, whereas 26.8 area is noted as good potential of groundwater along streams and paleochannels. Significantly, 33.6 of the area has moderate groundwater potential due to monsoonal recharge fluctuations. However, 28.9 of the area is found to have lower groundwater potential because of sub-surface settings and lack of recharge or permeability. The groundwater potential zones are cross-verified at selected locations based on in situ VES geophysical survey (vertical electrical sounding) and groundwater yield data. Among the six locations, the VES results indicate that the aquifers underlying unconfined and semi-confined formations have very good to good groundwater potential than other categories of aquifers. Moreover, the higher groundwater yield is estimated in good and very good zones, which indicates higher potentiality of groundwater sources. This study provides the geodatabase of primary information for planning and management of groundwater resources in the non-perennial river basin environment.