Aeolian sediment transport over the Gobi with high gravel coverage under extremely strong winds in the Hundred Miles windy area along the Lanzhou-Xinjiang High-Speed Railway
Aeolian sediment transport over the Gobi with high gravel coverage under extremely strong winds in the Hundred Miles windy area along the Lanzhou-Xinjiang High-Speed Railway
复制标题
兰新高铁百里风区特强风下砾石覆盖率高的戈壁风沙输送
DOI：
10.1016/j.jweia.2021.104857
复制
发表时间：
2021-11-26
影响因子：
4.8
通讯作者：
Shi, Boyuan
中科院分区：
文献类型：
--
作者：
Wang, Tao;Qu, Jianjun;Shi, Boyuan
在砾石覆盖率高的戈壁地区，由极强的风驱动的风成输运仍然知之甚少。在兰新高速铁路沿着百里风沙区，对砾石覆盖率为70-94%的戈壁风沙流进行了野外观测。结果表明，在典型的输运过程中，在砾石覆盖率较高的情况下，输运最强烈的时段可以发生近似连续的跃移，平均跃移层高度（0.58 ± 0.12 m）约为砂面跃移层高度的6倍。在年输沙量为705.14矢量单位（VU）的条件下，年输沙量为46.31 kg·m（-1）·a（-1），表明在极强风区砾石覆盖率高的戈壁表面，风沙活动仍然很强。此外，粒度分布表明，沙粒的跃移高度可达2米，和沉积物通量密度的累积频率表明，99%的泥沙输运在0-3米的表面。建议将拦沙栅的高度从目前的2 m提高到3 m，这样可以截留更多的输沙颗粒。
Aeolian transport driven by extremely strong winds over Gobi areas with high gravel coverage remains poorly understood. In this study, field observations of aeolian transport over a Gobi surface with 70-94% gravel coverage were performed in the Hundred Miles windy area along the Lanzhou-Xinjiang High-Speed Railway. The results reveal that during a typical transport event, approximately continuous saltation can occur in the most intense transport period under such high gravel coverage, and the average saltation layer height (0.58 +/- 0.12 m) is approximately 6 times larger than that over sand surfaces. The annual sediment transport rate reached 46.31 kg m(-1).a(-1) under an annual sand drift potential of 705.14 vector units (VU), indicating that wind-blown sand activities are still strong over Gobi surfaces with high gravel coverage in extremely strong windy areas. Furthermore, the grain size distribution indicates that the saltation height of sand particles can reach 2 m, and the cumulative frequency of the sediment flux density indicates that 99% of sand is transported within 0-3 m of the surface. Our findings suggest that the height of sand fences should be raised from the present 2 m-3 m, which can trap more transported sand particles.