Water‐Droplet Energy and Soil Amendments: Effect on Infiltration and Erosion

Abstract

Abstract The impact energy of water droplets from rain or overhead sprinklers can cause a seal to form at the soil surface. This constitutes a severe problem in agricultural lands in the arid and semiarid regions. Spreading a soil conditioner on the surface of the soil and providing a constant supply of electrolytes may prevent seal formation. The effect of droplet impact energy and water quality on infiltration and erosion was studied, using a tank drip‐type rain simulator, in a sandy loam soil (Typic Rhodoxeralf) treated with an anionic polyacrylamide (PAM) and phosphogypsum (PG). Three kinetic energies (KE) of 3‐mm diameter drops were obtained by varying their falling heights. The two qualities of water were distilled water (DW) and tap water (TW), to simulate rain and irrigation water, respectively. Increasing the impact energy reduced the infiltration rate (IR), cumulative infiltration (rain intake), and soil erosion in all treatments. Addition of PAM in the presence of electrolytes (either PG or TW) increased both final IR and cumulative infiltration by 7‐ to 8‐fold compared with the control, and was much more effective than PAM, PG, or TW alone. The PAM + electrolyte treatments decreased soil erosion by more than one order of magnitude compared with the control.