| In arid and semi-arid regions, wind erosion taking away nutrient-rich soil particles, will result in land impoverishment. Because low shrubs, regularly distributing on the soil surface, undertake part of the friction caused by wind and as a result weaken the direct effect of wind on soil, the intensity of wind erosion abated. Due to the shortage of water in arid and semi-arid areas, the rational plant allocation is needed to achieve maximization of ecological and economic benefits in the case of low coverage. In this paper, the wind speed, roughness, the rate of sand transporting near-surface and wind-break potency were analyzed contrastively in different shrub coppice forests with various configurations by life and artificial shrub field experiments, and several reasonable configurations of plant were tried to found out, in order to provide reference for vegetation construction in shifting sandland. The conclusions are as follow:(1) When the wind-sand flow through natural shrub, Wind speed increased initially and then decreased beside the shrub, and decayed sequentially in the Leeward side of shrub. The wind speed of the side was greater than that of the windward side, and wind speed was close to the natural one in 2H Department. The sediment discharge of each point mostly converged in the height range of 0～9 centimeters, which was accounted for over 80% in average. The sediment discharge order was:the wilderness> the side of the shrub 1H> windward side 1H> leeward side 1H.(2) The wind prevention effects of three shrub coppices with different row distributions at 0.2m height were:Three rows> two rows> only one row, Artemisia halodendron> Caragana Korshinskii Kom> Salix psammophila. The rate of sediment transporting of the forest belt had been reduced compared to the wilderness within 7H department. For the three shrub coppices, certain function of prevention and control of wind erosion was obvious within the 10H department for two-line and three-line configuration and within 7H for one-line configuration. The roughness of three shrub coppices had almost revived to the status of wilderness at the distance of 10H department.(3) The protection efficiency of the shrub belt with different configurations decreased with increasing of the bandwidth and the distance from the belt. After strong wind, three sand deposited before and after of the forest belt for three shrub coppices with the forming of "concave" surface between belts, and the bottom of the "Concave" was between 1.5m～6.5m after the first belt. There was nearly no wind erosion whithin the range of 1.6m after the first and before the second belt, where the sediment retention was better. The average wind prevention efficiency at the height of 0.2m was significantly better in forests with configurations of 4m (the best one),6m,8m than those of 10m and 12m for the three shrub forests. The effects of wind prevention and sand resistance were the best within 1-3H department, and unsatisfactory at the distance no shorter than 12H. There was no significant difference of the sediment retention capability among the three shrub coppices, however, with the increasing of bandwidth, the sediment retention capability of the Artemisia halodendron and Caragana Korshinskii Kom was slightly higher than that of Salix psammophila.
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