Splash erosion and infiltration in relation to mulching and polyvinyl alcohol application in semi-arid tropics

Abstract

Splash erosion, caused due to structural instability, leads to the formation of soil crust, which hampers infiltration rate of soils and affects the germination of seeds. To ensure the optimum infiltration rate and better germination, it is important that splash erosion and crusting are prevented. A study was carried out in sandy loam and silt loam soils to monitor the splash loss and infiltration rates in relation to application of straw mulch and polyvinyl alcohol (PVA) under simulated rainfall. The treatments included spreading chopped wheat straw on tilled soil at a rate of 6 t ha−1 and spraying of 0.1 and 0.5% PVA solutions on tilled soil surface, in addition to an untreated tilled soil as control. The treatments were replicated four times. The straw mulch application decreased the mean splash loss by 68% compared to unmulched soil. The mean basic infiltration rate (IR) measured, as an index of soil crusting, was 54% higher in soils with mulch cover than in soils without mulching. The average splash loss decreased by 56% with 0.1% PVA and 84% with 0.5% PVA application compared to untreated soil. The mean basic IR did not increase significantly, when treated with 0.1% PVA solution compared to untreated soils, whereas 0.5% PVA application increased the basic IR by 77%. The effect of mulch and PVA in decreasing splash loss and increasing IR was more effective in sandy loam than in silt loam.