Abstract:In order to provide theoretical basis for scientific prevention and control of sand dune hazard, in this paper, lab analysis and wind tunnel simulation were used to study the effects of sand moisture content on surface roughness length, wind velocity profile and structure of drifting sand flux in the Hobq Desert. According to the real dynamics of wind tunnel, the inlet wind speeds were set to be 6, 8, 10, 12, 14, 16 m/s. In addition to dry sand, artificially mixed sand, of which the moisture content was 0.25%, 0.5%, 1%, 1.5%, 2% and 2.5%, was also used for the wind tunnel simulation experiment. The results showed that the surface roughness length increased with the increasing wind speed and overall showed a trend of decrease with the increasing moisture content. Wind velocity profile showed a logarithmic distribution with height. As the wind speed increased, the logarithmic rule of wind velocity profile became better, wind velocity gradient decreased. When the moisture content increased, the absolute sand transport rate with the increase of wind speed decreased, but the relative value increased. As a whole, sand transport rate decreased with increasing moisture content. Under all moisture conditions, sand transport rate decreased with increasing height; when the moisture content reached 2.5%, the wind erosion process almost stopped, regardless of the height. About 80% of dry sand transport occurred within the first 5?cm near the surface, but when the moisture content increased, a higher proportion of sand transport occurred below 5 cm; when the moisture content was between 0.25% and 1.5%, sand transport occurred in the 5 cm to 8 cm layer near the surface accounted for more than 30% of the total sand transport. Our results indicated that the mechanical sand prevention measures which can increase the surface roughness length should be used in the Hobq Desert, and the height of the sand fixing measures should be higher than that in other deserts.