Abstract: In this paper,the data of horizontal and vertical sand-dust flux and the annual wind speed and direction during eight sandstorms,collected from the sandwatch tower near the surface layer (0-50 cm) of Inner Mongolia Dengkou Desert Ecosystem National Observation Research Station,were used.The purposes of the study were to analyze the variations of sand-driving wind regime,distribution of wind-blowing sand and the effect of shelterbelt on sandstorms on small scale in the northeast marginal zone of the Ulan Buh Desert.The results were as follows:① The average wind speed inside and outside the shelterbelt increased with the increase of height,the wind speed profiles during sandstorms could be expressed by the power exponential function,the prevailing wind directions inside and outside the shelterbelt were W,WNW and NE,but their proportions were different.② The horizontal wind-blowing sand flux and the sand-dust concentration outside the shelterbelt decreased with the increase of height.The distribution of wind-blowing sand accorded with the exponential function,the horizontal wind-blowing sand flux and sand-dust concentration inside and outside the shelterbelt increased slowly with the increase of height,and the distribution of wind-blowing sand accorded with the power exponential function.The vertical wind-blowing sand flux inside and outside the shelterbelt decreased significantly with the increase of height,and the distribution of wind-blowing sand accorded with the power exponential function.③ When sandstorm passed through the shelterbelt system,the wind speed was significantly decreased with an average reduction of 31.03%,while the horizontal and vertical fluxes of wind-blowing sand were reduced by 298.16 g·m^-2 and 0.37 g·m^-2 respectively,and the concentration of wind-blowing sand was decreased by 22.48 g·m^-2.

Key words: shelterbelt, wind speed, sandstorm, horizontal flux, vertical flux, wind-blowing sand concentration, Ulan Buh Desert