干旱区生态环境知识资源中心(Arid): 新月形沙丘顶点与沙脊线重合和分离的两种过程以甘肃河西走廊沙区为例

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	新月形沙丘顶点与沙脊线重合和分离的两种过程以甘肃河西走廊沙区为例
其他题名	Processes of Superposition and Separation of Barchan Dunes on the Top and Ridge Line: A Case Study in the Desert Areas of the Hexi Corridor
	常兆丰1 ; 马中华 2; 朱淑娟 1; 张剑挥 1; 段晓峰 1; 王强强 1; 王祺 1; 张德魁 1; 唐进年 1
来源期刊	干旱区研究
ISSN	1001-4675
出版年	2017
卷号	34 期号:1 页码:167-173
中文摘要	为了揭示新月形沙丘顶点与沙脊线重合和分离的两种过程,对甘肃河西走廊沙区绿洲边缘的新月形沙丘进行了调查观测,并在民勤绿洲边缘新月形沙丘上进行了流场观测。结果表明: ①新月形沙丘的顶点与沙脊线的重合和分离两种过程交替进行,春季≥5 m·s~(-1)的NW风是沙丘顶点与沙脊线重合的主要原因,夏季≥5 m·s~(-1)的SE风是沙丘顶点与沙脊线分离的主要原因。重合的过程也是沙丘前移的过程。②沙丘顶点与沙脊线重合时,沙丘顶点的风速大于上风向旷野风速;沙丘的顶点与沙脊线分离且当旷野风速≥8 m·s~(-1)时,沙丘顶点至沙脊线之间的风速小于上风向旷野风速。③从沙丘迎风坡底部到沙丘顶部,中沙增多细沙减少;沙丘各部位的细沙粒度与≥2 m·s~(-1)的风速正相关,中沙粒度与≥2 m·s~(-1)风速为负相关;沙丘各部位粒度的不确定性是由两个相反方向的风沙流过程造成的,此过程与沙丘顶点与沙脊线重合和分离两种过程的交替进行是对应一致的。
英文摘要	There are two statuses of sand activities on the top and ridge line of barchan dunes,i. e. the superposition and separation. In order to reveal the processes of these two statuses, in this study the barchan dunes in the oasis fringe in the desert areas,Gansu Province,were investigated and observed,and the flow field of barchan dunes in the Minqin oasis fringe was also observed. The results are as follows: ① The processes of superposition and separation of barchan dunes on the top and ridge line occurred alternately. The NW wind with wind speed≥5 m·s~(-1) in spring was the main cause of superposition of barchans dunes on the top and ridge line; while the SE wind with wind speed≥ 5 m·s~(-1) in summer was the main driving force of separation of barchans dunes on the top and ridge line. The superposition process was also the dune moving process; ② The wind velocity on the top of the dunes was higher than that at the upwind open field when the top and ridge line of dunes were coincide; the wind velocity from the top to the ridge line of dunes was lower than that at the upwind open field when the top and ridge line of dunes were separated and the wind speed at upwind open field was≥8.0 m·s~(-1); ③ The sand with particle size of 0.5 - 0.25 mm increased while that with particle size of 0.25 - 0.05 mm reduced from the bottom of windward slope to the dune top. The sand with particle size of 0.25 - 0.05 mm was positively correlated with the wind speed≥2 m·s~(-1) at different positions of dunes,while the sand with particle size of 0.5 - 0.25 mm was negatively correlated with the wind speed≥2 m·s~(-1). The uncertainty of particle size at different positions of dune was caused by the two sand flows with opposite directions,which was consistent with the alternative activity of the superposition or separation of the dunes on the top and ridge line.
中文关键词	新月型沙丘 ; 顶点 ; 沙脊线 ; 重合 ; 分离 ; 河西走廊 ; 甘肃
英文关键词	barchan dune dune top ridge line superposition separation Hexi Corridor Gansu
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOSCIENCES MULTIDISCIPLINARY
WOS研究方向	Geology
CSCD记录号	CSCD:5897505
来源机构	甘肃省治沙研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/235970
作者单位	1.甘肃省治沙研究所, 兰州, 甘肃 730070, 中国; 2.武威市气象局, 武威, 甘肃 730030, 中国
推荐引用方式 GB/T 7714	常兆丰,马中华,朱淑娟,等. 新月形沙丘顶点与沙脊线重合和分离的两种过程以甘肃河西走廊沙区为例[J]. 甘肃省治沙研究所,2017,34(1):167-173.
APA	常兆丰.,马中华.,朱淑娟.,张剑挥.,段晓峰.,...&唐进年.(2017).新月形沙丘顶点与沙脊线重合和分离的两种过程以甘肃河西走廊沙区为例.干旱区研究,34(1),167-173.
MLA	常兆丰,et al."新月形沙丘顶点与沙脊线重合和分离的两种过程以甘肃河西走廊沙区为例".干旱区研究 34.1(2017):167-173.