Influence of Super Absorbent Polymers on Infiltration Characteristics of Alfisols in Semi-Arid Region

Infiltration characteristics of the soil are important to understand the water dynamics in the root zone of a soil-plant system. A laboratory experiment was conducted to study the infiltration characteristics of sandy loam soil under different application rates of super absorbent polymers (SAPs). Four polymer products (P1, P2, P3 and P4) of the commercial value with different concentrations (0.25%, 0.75%, 1.25% and 1.75%) were used and compared with control (soil without polymer). Among four polymer products tested, SAP P3 showed maximum reduction (90%) in the steady state infiltration rate as compared to P1, P2 and P4 tested over different concentrations. The steady infiltration rate was decreased by 3.6 to 1.75, 4.1 to 0.4, 1.4 to 0.52 and 1.6 to 0.76 cm/hr under P1, P2, P3 and P4, respectively in the polymer concentrations of 0.25, 0.75, 1.25 and 1.75%. The infiltration data were fitted to Philip model and model parameters had the best description of the relationship between infiltration rate and application rate of super absorbent polymers in the sandy loam soil with significant reduction in saturated hydraulic conductivity (A) varying from 12.4 to 84.75%. Out of four polymers tested, P3 had more reduction capacity in the infiltration rates of sandy loam soils as compared to other SAPs.