The Effect of Soil Moisture Levels on the Threshold Velocity of Wind Erosion in Dust Centers of South and Southeast of Khuzestan Province-Ahwaz

One of the most important environmental hazards that is rising drastically in IRAN in the last decade is wind erosion causing the spread of soil particles. The present study aims to evaluate the effect of soil surface moisture on the wind erosion threshold velocity in three supercritical centers of dust, located in the regions of south and southeast of Khuzestan province. For this purpose, 11 soil samples from the selected regions were collected. The soil samples were prepared in terms of moisture contents (air-dry, 4, 7, and 9%). Then they were tested in a wind tunnel based on a completely randomized design. The results of comparing the mean values of wind erosion threshold velocity using Duncan method at a probability level of 5% confirmed that the effect of moisture on the erosion threshold velocity is significant for all samples. In addition, the two parameters of moisture and erosion threshold velocity was strongly correlated in all soil samples, so that with increasing moisture levels, the wind erosion threshold velocity also increased. The findings also confirmed that the amount of increase in velocity is different depending on the levels of moisture, indicating that increasing the moisture content from air-dry to 4% level yielded the largest change in threshold velocity, which could have a substantial effect in controlling the erosion phenomenon in the study regions.