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新疆策勒沙漠-绿洲过渡带的天然植被对绿洲内部的农田起到了很好的保护作用,具有良好的防风阻沙效益。对策勒沙漠-绿洲过渡带的流沙地、半固定沙地、固定沙地的水平输沙通量和风速进行了分析。结果表明:(1)近地表的输沙通量和平均风速从流沙地至半固定、固定沙地大幅度地减少。在0~202.5cm高度范围,半固定沙地、固定沙地水平输沙通量相比流沙地分别少了56.91%、90.23%;在0~70cm高度范围内,输沙通量分别少了85.31%、99.55%;(2)平均风速越大,半固定沙地、固定沙地相比流沙地的输沙通量减少得愈多,流沙地、半固定沙地、固定沙地近地表输沙通量与平均风速分别服从指数、线性和多项式函数关系;(3)策勒沙漠-绿洲过渡带的有效宽度不小于1.74km,才能保护绿洲免受风沙危害。
The natural vegetation in the Cele’er desert-oasis transitional zone of Xinjiang plays a very good role in protecting the farmland inside the oasis and has good windbreak and sand-blocking benefits. The horizontal sand transport fluxes and wind speeds in the sand desert, semi-fixed sandy land and fixed sandy land in the transition zone between Lele and Cameroon are analyzed. The results show that: (1) The sediment flux and mean wind speed of the near surface are greatly reduced from sandy soil to semi-fixed and fixed sandy land. In the height range of 0 ~ 202.5cm, the horizontal sediment transport loss in semi-fixed and fixed sandy land was 56.91% and 90.23% less than that in quicksand, respectively, while that in the 0 ~ 70cm height range was 85.31% %, And 99.55% respectively. (2) The greater the average wind speed, the more the sediment transport loss in the semi-fixed sand land and the fixed sand land is lower than that in the sandy land. The sand transport, semi-fixed sand and fixed sandy land near surface sediment transport The flux and average wind speed are subject to exponential, linear and polynomial functions, respectively; (3) The effective width of the Cele’er desert-oasis transitional zone is not less than 1.74 km in order to protect the oasis from sandstorm.