干旱区生态环境知识资源中心(Arid): Sand dunes as potential sources of dust in northern China

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	Sand dunes as potential sources of dust in northern China
	Sweeney Mark R; Lu Huayu; Cui Mengchun; Mason Joseph A; Feng Han; Xu Zhiwei
来源期刊	Science China. Earth Sciences
ISSN	1674-7313
出版年	2016
卷号	59 期号:4 页码:760-769
英文摘要	While saltation bombardment of sand grains on a fine substrate can produce considerable dust, the well-sorted nature of sand dunes tends to preclude them from consideration as major dust sources. Recent research, however, has revealed that sand dunes can, in some cases, be large sources of dust. We used the PI-SWERL (Portable In-Situ Wind Erosion Laboratory) to measure in the field the potential of sand dunes and other desert landforms to emit particulate matter <10 mum (PM-10) dust in the Tengger, Ulan Buh, and Mu Us deserts of northern China. Combined with high resolution particle size measurements of the dune sand, an assessment of sand dunes as a dust source can be made. Large active transverse dunes tend to contain little to no stored PM-10, yet they produce a low dust flux. Coppice dunes stabilized by vegetation contain appreciable PM-10 and have very high dust emission potential. There is a positive correlation between the amount of PM-10 stored in a dune and its potential dust flux. Saltation liberates loose fines stored in dunes, making them very efficient dust emitters compared to landforms such as dry lake beds and washes where dust particles are unavailable for aeolian transport due to protective crusts or sediment cohesion. In cases where large dunes do not store PM-10 yet emit dust when active, two hypotheses can be considered: (1) iron-oxide grain coatings are removed during saltation, creating dust, and (2) sand grains collide during saltation, abrading grains to create dust. Observations reveal that iron oxide coatings are present on some dune sands. PI-SWERL data suggests that low dust fluxes from dunes containing no stored dust may represent an estimate for the amount of PM-10 dust produced by removal of iron oxide coatings. These results are similar to results from dunes in the United States. In addition, PI-SWERL results suggest that dust-bearing coppice dunes, which cover vast areas of Chinas sandy deserts, may become major sources of dust in the future if overgrazing, depletion of groundwater, or drought destabilizes the vegetation that now partially covers these dunes.
英文关键词	Coppice dunes Transverse dunes Dust PI-SWERL Desert
类型	Article
语种	英语
收录类别	CSCD
WOS研究方向	Meteorology & Atmospheric Sciences
CSCD记录号	CSCD:5681043
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/335632
作者单位	Sweeney Mark R, Department of Earth Sciences, University of South Dakota, South Dakota, USA.; Lu Huayu, Laboratory of Earth Surface Process and Environment, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu 210093, China.; Cui Mengchun, Laboratory of Earth Surface Process and Environment, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu 210093, China.; Feng Han, Laboratory of Earth Surface Process and Environment, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu 210093, China.; Xu Zhiwei, Laboratory of Earth Surface Process and Environment, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu 210093, China.; Mason Joseph A, Department of Geography, University of Wisconsin-Madison, Wisconsin, USA.
推荐引用方式 GB/T 7714	Sweeney Mark R,Lu Huayu,Cui Mengchun,et al. Sand dunes as potential sources of dust in northern China[J],2016,59(4):760-769.
APA	Sweeney Mark R,Lu Huayu,Cui Mengchun,Mason Joseph A,Feng Han,&Xu Zhiwei.(2016).Sand dunes as potential sources of dust in northern China.Science China. Earth Sciences,59(4),760-769.
MLA	Sweeney Mark R,et al."Sand dunes as potential sources of dust in northern China".Science China. Earth Sciences 59.4(2016):760-769.