干旱区生态环境知识资源中心(Arid): 反向沙丘近地层气流变化及其对沙丘形态的影响

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	反向沙丘近地层气流变化及其对沙丘形态的影响
其他题名	The characteristics of inner boundary layer airflow over reversing dunes and its effect on dune morphological evolution
	潘凯佳; 张正偲; 梁爱民
来源期刊	中国沙漠
ISSN	1000-694X
出版年	2021
卷号	41 期号:2 页码:1-8
中文摘要	反向沙丘形态-动力学过程是风沙地貌的重要研究内容。选择腾格里沙漠东南缘推平沙地发育的反向沙丘为研究对象,采用二维超声风速仪对沙丘表面5个位置0. 25 m和0.5 m高度的气流进行野外观测。结果表明:(1)气流方向影响近地层气流特征。以沙丘脊线垂线为轴,0.25 m高度处沙丘脊线的垂线两侧风向变化不完全对称。当丘顶气流方向与脊线垂线角度差值为负时,迎风坡底部风速恢复较慢。(2)背风坡气流特征受风向控制。背风坡0.25 m与0.5 m高度气流变化规律相似,在背风坡中部发生偏转,但沙丘顶部气流方向与脊线垂线相差<10°时发生反向偏转。丘顶风向为285°315°(左偏)时,0. 25 m高度的偏转角度大于0.5 m高度的偏转角度。背风坡0.25 m与0.5 m高度处风速表现为脊线垂线两侧风速变化不一致。(3)沙丘表面气流影响沙丘形态。观测期间沙丘脊线发生明显移动,移动值为0.33 m。背风坡发生堆积,最大堆积厚度为0.44 m,迎风坡发生风蚀,最大风蚀深度为0.43 m。该研究结果证实了风在风沙地貌演化中的重要作用,为反向沙丘形态演化数值模拟提供数据支持。
英文摘要	The morphology-dynamic processing of reversing dune is an important issue in Aeolian geomorphology,but a little research have been done for these dunes,which limits our understanding of the dunes formation and development.For this reason,a developing reversing dunes in the southeast edge of Tengger Desert was selected.Ten-dimensional ultrasonic anemometer was used and set up at top,crest leeward stoss,dune toe,and windward stoss at 0.25 m and 0.5 m height over dune surface.The results indicated that:(1)The direction of airflow affects characteristics of airflow.Wind directions were not completely symmetry on the left and right sides of an axis perpendicular to the crest at 0.25 m height.When the flow angle between airflow directions and the direction of perpendicular line to the crest are negative,the wind speed at the windward slope recovers slowly.(2)The airflow characteristics of leeward slope are controlled by the wind direction.The variation of airflow at 0.25 m and 0.5 m height are similar,and deflection occurs in the middle of the leeward slope,and reversing deflection occurs within a range of 10° between the airflow direction at the top of the dune and perpendicular to the crest.However,when the wind at the top of the dune is 285°-315°,the deflection at 0.25 m is greater than that 0.5 m.The wind speed of 0.25 m and 0.5 m at the leeward slope is inconsistent on both sides of the direction perpendicular line to the crest.(3)Dune surface airflow affects dune morphology.During the observation period,the crest of dune moved significantly with a movement value of 0.33 m.Sediment accumulation occurred on leeward slope with the maximum thickness of 0.44 m,and erosion occurred on windward slope with the maximum depth of 0.43 m.The results of this study are important to clarify the effect of wind in the evolution of dune morphology and provide data for numerical simulation.
中文关键词	反向沙丘 ; 超声风速仪 ; 风速 ; 风向 ; 形态
英文关键词	reversing dunes sonic anemometer wind speed wind direction morphology
类型	Article
语种	中文
收录类别	CSCD
WOS类目	Geology
CSCD记录号	CSCD:6936953
来源机构	中国科学院西北生态环境资源研究院
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/354601
作者单位	潘凯佳, 中国科学院西北生态环境资源研究院;;中国科学院大学, ;;, 兰州;;, 甘肃;;北京 730000;;100049, 中国. 梁爱民, 中国科学院西北生态环境资源研究院;;中国科学院大学, ;;, 兰州;;, 甘肃;;北京 730000;;100049, 中国. 张正偲, 中国科学院西北生态环境资源研究院, 兰州, 甘肃 730000, 中国.
推荐引用方式 GB/T 7714	潘凯佳,张正偲,梁爱民. 反向沙丘近地层气流变化及其对沙丘形态的影响[J]. 中国科学院西北生态环境资源研究院,2021,41(2):1-8.
APA	潘凯佳,张正偲,&梁爱民.(2021).反向沙丘近地层气流变化及其对沙丘形态的影响.中国沙漠,41(2),1-8.
MLA	潘凯佳,et al."反向沙丘近地层气流变化及其对沙丘形态的影响".中国沙漠 41.2(2021):1-8.