风沙流输沙通量垂向分布研究
——以塔克拉玛干沙漠南缘流沙地表风沙流观测为例

摘要/Abstract

摘要： 于2010年4—6月在塔克拉玛干沙漠南缘策勒绿洲外缘流沙地进行风速、风向和输沙量同步观测,利用观测到的28组数据对输沙通量的垂向分布进行研究。结果表明,在4.5～8 m·s-1的风速区间内,总输沙率随风速增长速率较慢,大于8 m·s-1时增长迅速。在较小风速时,4个高度层(1 cm、3 cm、9 cm和19 cm)的输沙比率变化不明显,当风速大于6.6 m·s-1时,1 cm和19 cm高度输沙比率的调整较为明显,前者减小而后者增加,中间两层(3 cm、9 cm)则维持一定波动。不同的蚀积条件对于输沙通量的垂向分布具有一定的影响,平均跃移高度则在一定程度上反映了地表沙粒的吹蚀和堆积过程。在4种常见的描述输沙通量垂向分布的模型中,Zingg的修正幂函数具有最好的拟合程度,但反映的风沙流信息最少,简单幂函数的参数包涵了最为丰富的风沙流信息但拟合程度最差,指数函数同时具有较好的拟合程度和参数意义,Fryrear的幂函数则与指数函数恰恰相反。在沙物质以极细沙为主的塔克拉玛干沙漠南缘,指数函数较之简单幂函数能更好地描述该区域输沙通量的垂向分布,验证并补充了风洞实验的结果。综合比较认为,指数函数能更好地描述塔克拉玛干沙漠南缘输沙通量的垂向分布。

关键词: 塔克拉玛干沙漠, 流沙地表, 输沙通量, 垂向分布模型, 平均跃移高度

Abstract: Sand transport flux, wind speed and wind direction were observed simultaneously on bare sand surface at the southern rim of the Taklimakan Desert from April to June in 2010. Vertical distribution of sand transport flux was studied with the 28 groups of observed data. Results showed that total transport rate increased slowly when wind velocity ranged from 4.5 m·s-1 to 8 m·s-1 and increased sharply when wind velocity was higher than 8.0 m·s-1. The percentage of transport rate varied unnoticeably at lower wind velocities at the four examined layers (1 cm, 3 cm, 9 cm and 19 cm), but when wind velocity was higher than 6.6 m·s-1, the percentage of transport rate decreased at the lowest layer (1 cm) while increased at the highest layer (19 cm), yet it still remained unnoticeable variety at the other two layers (3 cm and 9 cm). The processes of surface erosion and sediment deposition had effect on vertical distribution of sand flux, and average saltation height reflected characteristics of these aeolian processes to some extent. Of the four frequently used models that described vertical distribution of sand flux, Zingg's modified power model produced the best fitness but the least message related to sand flow in its fitting parameters; the basic exponential model possessed the most message related to sand flow but the worst fitness; the exponential model took on a relatively good performance on both fitness and physical significance of parameters while Fryrears modified power model was reverse. At the fine sand dominated south margin of the Taklimakan Desert, the exponential model presented better fitness than the basic power model, and validated and enriched the conclusion that was drawn from wind tunnel experiment. Based on comprehensive comparison, the exponential model was considered to be the best one to describe vertical distribution of sand flux at the southern rim of the Taklimakan Desert.

Key words: the Taklimakan Desert, bare sand surface, sand transport flux, vertical distribution model, average saltation height

中图分类号:

X169

杨东亮, 王雪芹, 胡永锋, 杨帆, 韩章勇. 风沙流输沙通量垂向分布研究
——以塔克拉玛干沙漠南缘流沙地表风沙流观测为例[J]. 中国沙漠, 2012, 32(3): 631-639.

YANG Dong-liang, WANG Xue-qin, HU Yong-feng, YANG Fan, HAN Zhang-yong. Vertical Distribution of Aeolian Sand Mass Flux based on Field Observation at Southern Rim of the Taklimakan Desert[J]. JOURNAL OF DESERT RESEARCH, 2012, 32(3): 631-639.

参考文献

[1]李振山,倪晋仁.风沙流研究的历史、现状及其趋势[J].干旱区资源与环境,1998,12(3):89-97.

[2]柳本立,张伟民,刘小宁,等.莫高窟顶戈壁偏东风作用下输沙率变化的观测研究[J].中国沙漠,2010,30(3):516-521.

[3]廖空太,李耀辉,刘虎俊,等.库姆塔格沙漠羽毛状沙垄风沙活动强度特征[J].中国沙漠,2008,28(3):399-404.

[4]屈建军,井哲帆,张克存,等.HDPE蜂巢式固沙障研制与防沙效应实验研究[J].中国沙漠,2008,28(4):599-604.

[5]冯大军,倪晋仁,李振山.风沙流中不同粒径组沙粒的输沙量垂向分布实验研究[J].地理学报,2007,62(11):1194-1200.

[6]Butterfield G R.Near-bed mass flux profiles in aeolian sand transport:High-resolution measurements in a wind tunnel[J].Earth Surface Processes and Landforms,1999,24:393-412.

[7]吴正.风沙地貌与治沙工程学[M].北京:科学出版社,2003:61-71.

[8]Panebianco J E,Buschiazzo D E,Zobeck T M.Comparison of different mass transport calculation methods for wind erosion quantification purposes[J].Earth Surface Processes and Landforms,2010,24:393-412.

[9]Williams G.Some aspects of Aeolian transport load[J].Sedimentology,1964,3:257-287.

[10]Dong Z B,Liu X P,Wang H T,et al.The flux profile of blowing sand cloud:A wind tunnel investigation[J].Geomorphology,2002,49:219-230.

[11]Zobeck T M,Fryrear D W.Chemical and physical characteristics of windblown sediment I.Quantities and physical characteristic[J].Transactions of the ASAE,1986,29(4):1032-1036.

[12]Offer Z Y,Goossens D.Thirteen years of aeolian dust dynamics in a desert region(Negev desert,Israel):Analysis of horizontal and vertical dust flux,vertical dust distribution and dust grain size[J].Journal of Arid Environments,2004,57:117-140.

[13]Mertia R S,Privabrata Santra,Kandpal B K,et al.Mass-height profile and total mass transport of wind eroded aeolian sediments from rangelands of the Indian Thar Desert[J].Aeolian Research,2010,2(2-3):135-142.

[14]Nickling W G.Eolian sediment transport during dust storms:Slims River Valley,Yukon Territory[J].Canadian Journal of Earth Sciences,1978,15(4):1069-1084.

[15]Liu X,Dong Z,Wang X.Wind tunnel modeling and measurements of the flux of wind-blown sand[J].Journal of Arid Environments,2006,66:657-672.

[16]Gillette D A,Pitchford A M.Sand flux in the northern Chihuahuan desert,New Mexico,USA,and the influence of mesquite-dominated landscapes[J].Journal of Geophysical Research,2004,109,F04003.

[17]Ni J R,Li Z S,Mendoza C.Vertical profiles of aeolian sand mass flux[J].Geomorphology,2002,49:205-218.

[18]Fryrear D W,Stout J E,Hagen L J,et al.Wind erosion:Field measurement and analysis[J].Transactions of the ASAE,1991,34(1):155-160.

[19]Vories E D,Fryrear D W.Vertical distribution of wind-eroded soil over a smooth,bare field[J].Transactions of the ASAE,1991,34(4):1763-1768.

[20]Chen W N,Yang Z T,Zhang J S,et al.Vertical distribution of wind-blown sand flux in the surface layer,Taklimakan Desert,Central Asia[J].Physical Geography,1996,17(3):193-218.

[21]Funk R,Skidmore E L,Hagen L J.Comparison of wind erosion measurements in Germany with simulated soil losses by WEPS[J].Environmental Modelling & Software,2004,19:177-183.

[22]Li Z S,Feng D J,Wu S L,et al.Grain size and transport characteristics of non-uniform sand in Aeolian saltation[J].Geomorphology,2008,100:484-493.

[23]董玉祥,Hesp P A,Namikas S L,等.海岸横向沙脊表面风沙流结构粒度响应的野外观测研究[J].中国沙漠,2008,28(6):1022-1028.

[24]张立运,夏阳.塔克拉玛干沙漠南缘绿洲外围的天然植被[J].干旱区研究,1997,14(3):16-22.

[25]钱亦兵,张希明,李晓明.塔克拉玛干沙漠南缘绿洲沙物质粒度特征[J].中国沙漠,1995,15(2):131-135.

[26]刑文娟,雷家强,王海峰,等.荒漠-绿洲过渡带风况及输沙势分析——以策勒县为例[J].干旱区研究,2008,25(6):894-898.

[27]张伟民,汪万福,张克存,等.不同沙源供给条件下砾石床面的风沙流结构与蚀积量变化风洞实验研究[J].中国沙漠,2009,29(6):1015-1020.