The effect of water quality and storm sequence upon infiltration rate and crust formation

The effect of applications of distilled water (DW) and saline water (SW) (EC: 5.0 dS m^?1) upon the infiltration rates (IR) of crusted soil surfaces was studied using a rain simulator. A sandy loam and silt loam were placed in trays at a slope of 5%. The soils were pre-wet before each storm and a water table maintained at a depth of 5 cm. IR losses due to crust formation during storms of DW could be reversed by the use of SW in subsequent storms. A minor increase in IR was obtained in the silty loam soil, the crust of which stayed entire during successive rainstorms. Complete reversibility of IR was possible in the sandy loam, the crust of which was destroyed and reformed due to rainfall impact during each successive storm. The cohesion of the particles in the crusted silty loam soil was sufficient to render it resistant to raindrop impact, but cohesion between the particles of the sandy loam was insufficient to prevent reworking by rainfall impact during each storm. Crust formation therefore occurs in each storm in the sandy loam and the IR obtained is a consequence of the EC of the applied water of that storm only.