Characterization of Groundwater Quality in the Transitional Plain of Luni Basin and its Suitability for Agricultural Uses

Abstract

Groundwater quality was assessed for irrigation purposes by collecting
groundwater samples from 113 locations during pre-monsoon seasons in Jalore district
(Rajasthan). These groundwater samples were analyzed for physico-chemical parameters
like pH, EC, TDS, major cations, and anions. Furthermore, irrigation quality indices like
salinity hazard, chloride hazard, carbonate and bicarbonate hazard and sodium hazard
were calculated using the analytical results. These parameters were compared with
standard limits for irrigation use for the prevailing crops. Generally, hydrochemical
results indicate that the groundwater in the study area is neutral to very strongly
alkaline in nature. Based on the EC classification, most of the groundwater samples are
falling under the high to very high salinity hazard category. The order of abundance
of major cations and anions in groundwater was found as Na+>Ca2++Mg2+>K+ and
Cl–>SO42–>HCO3–>CO3–. Based on the EC and SAR, classification >60% of the samples is
falling under the moderate to a high reduction in infiltration rate category. In addition,
the study also emphasized that the practice of very high saline and moderately sodic
groundwater for irrigation may cause soil salinity as well as sodicity in soils. The study
found that the majority of the groundwater samples are above the minimum irrigation
water quality standards, suggesting that necessary action is required for sustainable
crop production by using appropriate management practices in the area.