Field observations on the protective effect of semi-buried checkerboard sand barriers

Semi-buried checkerboard sand barriers, especially those made of wheat straw and rolled reeds, are a widely used, cheap and practical sand stabilization measure in China. Such sand barriers can halt near-surface sand flow by increasing underlying surface roughness, reducing near-surface wind velocity, and weakening sand transportation intensity, thereby stabilizing the sand surface. Vortex actions within the cells of the grid produce a stable, concave surface after erosion and deposition reach equilibrium. Experiments showed that 1.0 × 1.0, 1.5 × 1.5, and 2.0 × 2.0 m straw sand barriers in a checkerboard pattern offer significant protection, whereas 0.5 × 0.5 m sand barriers are expensive and can be buried rapidly by sand, thereby losing their protective effect. Similar sizes of checkerboard sand barrier provide different protection depending on topography. Accordingly, the protection provided by semi-buried checkerboard sand barriers should be evaluated based on the sand flow field and topography.