Abstract:
Using electronic total station and RTK to sample the three dimensional form of Populus euphratica dunes, the experimental model of the Populus euphratica dunes was made based on the measured data. In wind tunnel, 3 groups of different wind speeds (6, 10 and 14 m/s) were applied to simulate the pure airflow field of the Populus euphratica dune model. Combined with the grain size distribution characteristics of the surface sediments of Populus euphratica dunes, the accuracy of the flow field wind tunnel simulation was confirmed, and sediment transport rate was measured under 5 different wind speeds (6, 8, 10, 12, 14 m/s) after 100 cm of Populus euphratica dunes. The results show that the air flow is stronger in the windward slope of the Populus euphratica dune, and it accelerates along the windward slope of the dune. The air flow intensity decreases obviously on the leeward slope of dune, and a part of the air flow direction reverses, forming a strong eddy area. Finally, the air flow intensity gradually returns to the rear of the dune. The flow change characteristics of Populus euphratica dune coincide with the grain size distribution characteristics of the surface sediments of Populus euphratica dune.Behind the Populus euphratica dune, the rate of sand transport decreased rapidly with the increase of height,the amount of wind erosion and sediment transport is 78% of no vegetation, and the sediment transport volume is obviously less than that in the flat sandy land.
