Abstract: Barchan dune is an important type of aeolian landform and forms during the process of desertification. In the previous researches, more researchers focused mainly on the surface dynamic process of barchan dune but less on the influence of barchan dune on surface wind erosion during desertification process. In this paper, the plugging-brazing method was used to measure the distribution pattern of wind erosion/deposition on the surface around barchan dunes at the Taitema playa. The wind tunnel was used to simulate the distribution pattern of airflow over the typical barchan dune. The mechanism of barchan dune affecting surface wind erosion around dune was analyzed. The results showed that the airflow structure changed with the varying geometry shapes of barchan dunes, and it affected significantly the intensity of wind erosion/deposition over the surface. Although the wind erosion depth and sedimentary thickness were slightly greater than those on flat sand, the average volume of net wind erosion per unit area was close to an equilibrium in the frontal region of windward slope and on both sides of dunes. Deposition was dominant in the frontal region on leeward slope of barchan dune, but wind erosion was dominant on the surface of flank wake zone of leeward slope. The average volume of net wind erosion per unit area was slightly increased with the increase of dune size. In a word, the barchan dunes affect the intensity of surface wind erosion and deposition during the process of desertification in playa.

Key words: barchan dune, distribution of wind erosion and deposition, intensity of wind erosion, airflow structure, Taitema Lake