To Study the Effect of Irrigation Water Quality on the Soil Productivity of Pehowa Block of Kurukshetra District, Haryana, India

Abstract

Groundwater plays a crucial role in Indian agriculture, acting as a main source for irrigating crops. It is likewise the most extensively harvested raw material in the world. In dry and semi-dry areas, evaluating groundwater quality for irrigation is crucial because of the demands from growing populations, urbanization, and industrial growth. The elevated salt levels in soil and irrigation water present a major threat to the productivity and sustainability of agriculture. Soil salinity restricts crop growth by obstructing water uptake, inducing osmotic stress, and modifying nutrient availability. Likewise, elevated salt concentrations in irrigation water directly affect the quality of water used for agricultural purposes. This may lead to diminished crop yields, delayed plant growth, lower nutrient uptake, and heightened susceptibility to pests and illnesses. In 2023, fifty water samples were gathered from villages in the Pehowa block of Kurukshetra district to assess the groundwater quality of that specific area. All the fifty irrigation water samples were analyzed for a range of hydrochemical parameters, including pH, electrical conductivity (EC), cations (Ca²⁺, Mg²⁺, Na⁺, and K⁺), and anions (CO₃²⁻, HCO₃⁻, Cl⁻, and SO₄²⁻) using standardized methods. Additionally, irrigation indices such as Sodium Adsorption Ratio (SAR) and Residual Sodium Carbonate (RSC) were also calculated. The results revealed that groundwater pH ranged from 7.65-8.82, EC varied between 0.44-1.81 dSm-1, SAR was between 2.67-11.40 mmol1/2 L-1 and RSC ranged from 0.00 to 5.07meq L-1. The concentration of cations viz., Ca2+, Mg2+, Na+ and K+ varied from 0.31-1.00, 0.73-2.73, 2.45-13.24, 0.16-0.45 me L-1 with mean values of 0.47, 1.34, 5.32, 0.28 me L-1, respectively. Likewise, the concentration of anions viz., CO32-, HCO3-, Cl- and SO42- varied from 0.00-1.6, 0.16-6.32, 1.71-6.54, 0.50-3.75 me L-1 with average values of 0.06, 1.46, 3.30, 2.03 me L-1, respectively. It shows the trend among the average ionic concentration of cations and anions were Na+>Mg2+> Ca2+> K+ and Cl->SO42->HCO3-> CO32-, respectively. According to AICRP, 1989 in Pehowa block 82, 14 and 4% samples were found in good, marginally alkali and highly alkali categories, respectively. Likewise, soils of village Mohan Nagar and NayaDiwana which are receiving highly alkali irrigation water continuously from last many years have accumulated Na+ (26.0 and 25.2 meq L-1), HCO3- (15.5 and 14.20 meq L-1) and CO32- (3.42 and 4.5 meq L-1), respectively in 0-15 cm soil. Due to accumulation of Na+, HCO3- , CO32-, soil pH is more than 8.5 and SAR is more than 10. The results indicated that the increasing RSC in irrigation water significantly increased the pH, ECe and SAR of the soil. Spatial variability maps of EC, pH, SAR and RSC of irrigated ground water were also prepared for the Pehowa block of Kurukshetra district. The results obtained in this study and the spatial database established in GIS will be helpful for monitoring and managing groundwater quality in the study area.