Quantifying macroporosity and preferential flow variations in soil under rice and wheat cultivation

Soil macropores play a vital role in movement of water in agricultural fields, yet their spatial and structural dynamics under intensive crop rotation systems remain poorly quantified. This study investigates the contrasting effects of rice‐wheat cultivation on soil hydraulic properties, macropore function, and preferential flow dynamics. Field experiments were conducted post‐harvest of rice and wheat crops at an agricultural plot in IIT Kanpur. Dye‐tracer experiments were performed for visual confirmation of preferential flow. Tension disc and double ring infiltrometer measurements were taken at six different locations at 3 depths (10, 25, and 50 cm). The parameters for matrix ( and ) and macropore ( ) domains were estimated. Wheat soil exhibited significant difference depth‐wise in infiltration rate (). Critically, the steady‐state flux at 25 cm was 77.53% greater, indicating the sporadic activation of deep, high‐capacity macropores within a restrictive layer. No significant depth‐wise variation was observed in parameters under rice cropping (). Matrix parameters were significantly higher under wheat when compared to rice (mean: cm h −1 , cm −1 for rice; 24.26 cm h −1 , for wheat) and showed significant depth‐wise variation at 25 and 50 cm. This trend confirms the restorative and deep‐reaching effect of the wheat root system on pore continuity and subsoil structural stability. The findings emphasize that preferential flow under rice and wheat cultivation is dynamic and crop‐dependent, governed by alternating phases of structural degradation and recovery.