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干旱区地理 ›› 2016, Vol. 39 ›› Issue (3): 495-503.

• 地表过程研究 • 上一篇    下一篇

砾质戈壁在不同扰动方式下的风蚀量研究——以敦煌雅丹地质公园北边的砾质戈壁为例

殷代英, 屈建军, 赵素平, 谭立海, 安志山, 肖建华   

  1. 中国科学院寒区旱区环境与工程研究所敦煌戈壁荒漠生态与环境研究站甘肃省风沙灾害防治工程技术研究中心, 甘肃 兰州 730000
  • 收稿日期:2015-12-15 修回日期:2016-03-01 出版日期:2016-05-25
  • 作者简介:殷代英(1985-),女(汉族),理学硕士,工程师,主要从事风沙工程研究.Email:yindaiying@lzb.ac.cn
  • 基金资助:

    中科院寒旱所人才基金(51Y451311);冰川冻土学特殊学科点人才培养基金(J121003/J0109)

Amount of wind erosion to gravel gobi under different disturbing modes

YIN Dai-ying, QU Jian-jun, ZHAO Su-ping, TAN Li-hai, AN Zhi-shan, XIAO Jian-hua   

  1. Dunhuang Gobi and Desert Ecology and Environment Research Station, Lanzhou 730000, Gansu, China;Cold and Arid Region Environmental and Engineering Research Institute, Lanzhou 730000, Gansu, China;Chinese Academy of Sciences. Gansu Center for Sand Hazard Reduction Engineering and Technoogy Lanzhou 730000, Gansu, China
  • Received:2015-12-15 Revised:2016-03-01 Online:2016-05-25

摘要: 通过野外移动式风洞,测定了雅丹的砾质戈壁在不同破坏方式、破坏强度、不同风速和不同破坏面积下的风蚀量。结果表明:砾质戈壁不同破坏方式下的风蚀量为:车碾压> 剥去砾石破坏> 不去砾石破坏> 脚踩踏;不同破坏强度下的风蚀量为:车碾压三道>车碾压一道。连续破坏的风蚀量要明显高于间隔破坏。无论在哪种破坏方式和破坏强度下的风蚀量都要远远大于自然床面。不同破坏方式引起的风蚀量随着风速的增大呈指数增加,当风速低于10 m·s-1时床面以轻微侵蚀为主,当风速>12 m·s-1时床面以强烈侵蚀为主。戈壁破坏面积与风蚀模数无关,因此可以利用风蚀量乘以对应的面积来估算各个破坏面积下的风蚀总量。不同扰动方式与强度对风沙流结构也有明显影响。

关键词: 砾质戈壁, 扰动方式, 风速, 风蚀量, 风沙流结构

Abstract: Field wind tunnel experiments were conducted in Yardang Gravel Gobi to measure the amount of wind erosion under different disturbance modes, wind speeds and disturbance areas. Five free wind speeds were selected in this study, i.e., 8, 10, 12, 14 and 16 m·s-1. The sand dust at different heights was collected using the sand sampler with a height of 20 cm having the interval of 2 cm for each entrance, and eolian processes were measured by weighing transducer. Results show as follows:(1) the wind erosion amount varied under different disturbance modes and different disturbance intensity, and was the severest under triple crushing by trucks among the five disturbance modes, the slightest under natural bed mode, indicating that the disturbance with more intensity led to greater wind erosion. The wind erosion amount under the continuous disturbance was significantly higher than that under interval disturbance.(2) Wind erosion amount increased exponentially with the increase of wind speed:when wind speeds was 8 to 10 m·s-1, wind erosion of gravel Gobi surface was relatively slight; while strong wind erosion occurred when wind speed increased to larger than 12 m·s-1.(3) The damage areas of Gobi is irrelevant to wind erosion modulus, so the total amount of wind erosion under different disturbing area can be estimated by multiplying the wind erosion amount with the corresponding disturbing area.(4) The wind-sand flow structure can also be affected by the different disturbance modes. The largest value of sediment runoff appeared in the height of 4-6 cm above earth surface rather than generally 0-1 cm, showing the so called "Trunk Effect" which was unobvious for large disturbance. This may be related to the fact that the collision between sand and the ground decreased significantly as the surface had only abundant sand without gravel on it after a strong disturbance.(5) The wind erosion amount reached the highest value after ~60 s under calm wind for the quadrat without gravel destruction above Gobi surface, while during ~20 s for the quadrat with gravel destruction, showing that the gravel Gobi surface with disturbances reached a steady state after the surface sand was taken away by wind. This result can provide a new method to predict the total amount of wind erosion for engineering construction and tourism development and resources utilization in the Gobi region, and also a scientific and technical basis for the enforcing law of administration on soil and water conservation. Improving the Gobi protection awareness has the important theories worth in regional ecological balance protection.

Key words: gravel Gobi, disturbance modes, wind speed, the amount of wind erosion, wind-sand flow structure

中图分类号: 

  • P931.1