Geospatial Assessment of Groundwater Quality for Irrigational Suitability and Uses for the Region of Manipur Valley, India

A comprehensive spatiotemporal qualitative investigation and assessment of groundwater resources of Manipur Valley were carried out to evaluate their suitability for irrigational uses and geospatially identify the vulnerable groundwater zones. In this regard, 140 grided representative samples during pre-monsoon and post-monsoon were collected from the region along with their in-situ parameters. The groundwater suitability for irrigational uses was evaluated based on significant water quality parameters and indices. The study highlights that except for a few parameters and indices for selected parts of the region, most of the samples were found under suitable categories. Few samples with elevated electrical conductivity values and higher sodium concentrations signify the possibility of alkalinity and salinity hazards for prolonged uses of groundwater for irrigation. The study witnessed the presence of saline aquifer in the region where samples exhibit higher salinity (>1000 ppm) and can potentially cause salinity hazards for prolonged uses of groundwater for irrigation. The hydrogeochemical classification reveals the dominance of the HCO3--Ca2+ type of water followed by mixed-type water due to rock weathering dominance during both seasons. Thus, the study highlights the comprehensive spatiotemporal scenario of groundwater quality for irrigational uses in the region through spatial mapping to identify the vulnerable groundwater zones for sustainable agricultural soil management.