Sustainable Groundwater Development and Management in a Tropical Savanna Region of Eastern India

Abstract

Regional sustainability and spatio-temporal variability of groundwater level (GWL) in newlinetropical savanna climatic region with heavily stressed aquifers needs future projection newlineskills by taking hydrological, geological, and climatic (HGC) controls into newlineconsideration. This study analyzed the spatio-temporal variability of quarterly GWL newlineand the regulating HGC controls it during the 1995-2015 period over a data-scarce newlinetropical savanna region in India. Using data mining techniques, the study evaluated newlineland use land cover (LULC), geomorphology, lithology, topography, and rainfall as newlineHGC controls for GWL variability. The analysis revealed that this region has high newlineintra-annual spatial variability characterized by higher GWL variability in the drier newlineperiod of the year than wet period. The temporal analysis of GWL demarcated the newlinedistinct regions with highly significant rising and declining trends with magnitude newlineranging from -0.51 to 0.42 m/year. It was discovered that the LULC could explain the newlineobserved GWL variability with the highest degree as compared to the other newlineconsidered HGC controls. Subsequently, through principal component analysis (PCA) newlinesix representative components covering more than 90% of the variance in 2002 LULC newlinedataset were used for training the random forest (RF) learning algorithm to develop newlinefour prediction models corresponding to four temporal quarters. The PCA-RF based newlinetrained prediction models showed adequate accuracy during testing using the 2005, newline2010, and 2015 LULC datasets. The developed models were further used to make newlineshort- and long-term GWL predictions in the study region. The developed models can newlinecontribute to regional-scale groundwater planning and management. The results newlineobtained on the dominancy of HGC controls can contribute to subsequent mapping newlineand modeling analysis at finer resolutions. newlineAs a basin-scale study, an integrated approach for concurrent delineation of newlinegroundwater storage and recharge potential zones using remote sensing, geographical newlineinformation systems (GIS), and analytical