Abstract:

The Wuhai-Maqin Highway is of great significance to the formation of urban agglomerations and regional economic development in northwest China. To prevent the highway from being threatened by wind-sand hazards, field observations and investigations of aeolian environments, dune types and their distribution rules, and the characteristics of the surface sediment along the Wuhai-Maqin Highway were conducted. During the observational period, the results show that the average annual wind speed was 2.86 m·s^-1. The annual value of the sand-drifting wind was 6.23 m·s^-1. The major directions were NW-NNW and E-ESE. From northeast to southwest, the sand transport potential and maximum possible sand transport show a decreasing trend but still belong to low wind energy environments. All the dunes in the plots were mobile dunes, except in plot 5, where the dunes were fixed. The type of dunes was primarily grid dunes. Under the action of wind, the main beams of the grid dunes primarily extend NE-SW. Moreover, from the northeast to the southwest, the height of the typical dunes increase as a result of the altitude and local environment. The grain sizes of the surface sediments of the dunes in the study area correspond primarily to medium and fine sands, with good sorting properties. The skewness is positive or extremely positive, and the kurtosis is medium and broad. Based on the above results, a comprehensive protection system of “six belts in one” is proposed to ensure the safe operation of the Wuhai-Maqin Highway.

Key words: sand-drifting wind, drift potential, grid dunes, Wuhai-Maqin Highway