Evaluation of Oil Mulch Effect on Wind Erosion Threshold Velocity and Some of Soil Properties, (Case Study: Dehloran, Ilam)

Mulching is a method of controlling wind erosion in arid and desert areas. In this study, the effects of oil mulch on some properties of soil were investigated, and the optimum amount of mulch to wind erosion control in Dehloran, Iran, was determined. For these purposes, after a mulching practice, soil samples were taken from the three treatments of mulched, control and the afforestation area at two depths of 0-10 and 10-50 cm through monthly field surveys during a year to measure soil parameters, including temperature, soil moisture, pH and EC. Then, the threshold velocity of wind erosion was determined using a wind tunnel and the optimum amount of mulch for erosion control was calculated. The results of soil characteristics analysis showed that soil temperature was significantly affected by the depth and season of sampling and their interactions, in contrast, soil moisture was only affected by the season. Also, soil pH was affected by all independent variables, while EC was only affected by the treatments. Na and SAR were not significantly affected by treatment, depth, and their interactions, while OM was significantly affected by treatment and the interaction between depth and treatment. Finally, the wind tunnel results showed that the erosion threshold velocity in the control area, at the height of 30 cm, was 4.84 m/s. Results also showed that mulching practice can control wind erosion under the maximum wind speed of the region and 7 tons/ha was recommended for future mulching practices in the region and similar areas.