艾比湖干涸湖底不同地表类型风蚀强度及粉尘输移通量的风洞试验研究

Wind Tunnel Study of Wind Erosion and Dust Flux on Different Surfaces in Dry Ebinur Lake,Xinjiang,China

以新疆准格尔盆地西部艾比湖干涸湖底及相关邻近地区7种不同形态的原状土为研究对象,通过风洞模拟试验,揭示干涸湖底不同地表类型的风蚀强度和沙/盐尘低空输送通量。结果表明：粉状盐漠和含盐量较低的淤泥-粘土混合物临界启动风速最低,硬质盐壳的临界启动风速最大;大于16 m·s^-1的大风是造成艾比湖干涸湖底风蚀的主要动力,7种地表类型中湖相沉积物、风积物、粉状盐漠的风蚀率最大,是风蚀尘暴的主要尘源;风蚀过程中颗粒的初始运动主要集中在0～10 cm高度范围内,以近地面跃移为主,风积物、湖相沉积物和粉状盐漠的输移通量最大。

Seven forms of original soil samples were sampled from dry Ebinur Lake and neighboring region in western Jungar Basin, Xinjiang. Their susceptibility to wind erosion and the dust flux has been tested in a wind tunnel. Results showed that： The threshold wind velocity is the smallest on the powdery salt crust and the silt-clay mixed sediment crust with lower salt content, and the largest on the hard salt crust; Gale with velocity over than 15 m·s^-1 is the main erosion force; The lacustrine sediments, eolian sediment and powdery salt crust among the 7 types of surface crusts have higher erosion rates, which are the principal dust sources of dust- and salt-dust storms; Particles transportation are originally concentrated with 0 to 10 cm height, and predominated by saltation ; The flux over lacustrine sediments, eolian sediment and powdery salt crust are lager.