Numerical simulation of the evolution and propagation of aeolian dune fields toward a desert–oasis zone

In this study, the evolution and propagation of aeolian dune fields toward a desert–oasis transitional zone are numerically investigated through considering the spatial variation of wind speed and the influence of vegetation on sand erosion and transportation etc. The propagation speed at the edge of desertified land and the influence of a straw checkerboard are quantitatively analyzed. Results show that evolution time, wind speed and sand diameter have obvious impacts on the propagation of desert and desertified land. A formula describing the propagation speed of desertified land with respect to wind speed and vegetation coverage is given. In addition, when considering the effects of straw checkerboards, the propagation speed of the downwind desertified land is found to be related to the length of and distance from the checkerboard area.