Abstract:In this study, we simulated wind erosion mechanism and sand-fixation effects of three shrub communities varying in spatial arrangement in a wind tunnel experiment with specific reference to sand-fixation forests at 18%-20% coverage. Plants within the three shrub communities were arranged as belts, equal-spacing, or random. Results showed that when wind speed was at 10m/s, wind erosion did not occur in the belt shrub community after 30 min of the treatment; whereas wind erosion occurred in the equal-spacing and random shrub communities within 8min and 3min, respectively, of the treatment. When wind speed was increased to 15m/s, light degree of wind erosion and sand accumulation occurred in the belt shrub community, and steady “concave” sand surface developed after 30min, with the maximum loss and accumulation at 0.4cm and 0.7cm, respectively. Moreover, the wind-driven sand flow was not formed in the belt shrub community after 30min; whilst strong wind-driven sand flows were formed in the equal-spacing and random shrub communities, with as much as 65.57% and 66.96% sand being blown off after 30min. Wind erosion in the equal-spacing shrub community mainly occurred in the free space between plants; whereas in the random shrub community, the space with distant plant distribution suffered from wind erosion and that of the packed plant distribution accumulated sand, forming a complex pattern of sand surface.