毛乌素沙地西北部植被覆盖对沙丘移动的影响

doi:10.7522/j.issn.1000-694X.2020.00020

摘要/Abstract

摘要：

毛乌素沙地生态环境脆弱，近年来沙漠化虽整体呈逆转状态，但西北部仍存在沙丘活化现象，风沙活动强烈，对下风向植被恢复和农牧生产造成了一定影响。利用Google Earth卫星影像对2002—2015年毛乌素沙地西北部裸露沙丘和植被覆盖沙丘进行监测，分析了植被覆盖与沙丘移动之间的内在联系。结果表明：（1）毛乌素沙地西北部存在较严重的风沙活动，沙丘移动速度为0.38~6.05 m·a^-1，其中植被覆盖沙丘平均移动速度为2.29 m·a^-1，裸露沙丘平均移动速度为4.59 m·a^-1，沙丘平均移动方向为122.5°，与当地合成输沙方向基本一致。（2）沙丘移动速度与高度呈负相关，但相关系数比前人报告的低，这与沙丘表面覆盖植被的时空变化密切相关。（3）植被覆盖对沙丘形态变化具有明显的影响，盖度增加使沙丘形态趋于饼状，从而逐渐被固定。（4）风况、地表盐渍化和公路两旁的固沙措施等也影响了沙丘的移动速度。

关键词: 沙丘移动, 形态演变, 植被, 毛乌素沙地

Abstract:

The ecological environment is fragile in the Mu Us Sandy Land. Although as a whole the desertification has been reversed in recent years, there is still sand dune activation in the northwest of the sandy land and the sandstorm activity is strong, which has impact on the downwind vegetation restoration and agricultural and pastoral production. Google Earth satellite images were used to monitor the migration characteristics of bare dunes and dunes with vegetation in the northwest of the Mu Us Sandy Land from 2002 to 2015, and the internal relationship between vegetation cover and dune migration was analyzed. The results showed that: (1) The sand transport activity in the northwest of Mu Us Sandy Land is more serious than any other regions. The dune migration rate is 0.38-6.05 m·a^-1, and dune migration direction is 122.5° which is similar to the local resultant drift direction. The average migration rate of dunes with vegetation is 2.29 m·a^-1, while that of bare sand dunes is 4.59 m·a^-1. (2) The dune migration rate is negatively correlated with dune height, but the correlation coefficient is lower than previous studies, which is closely related to spatio-temporal changes of vegetation cover. (3) Dune morphology is complex. Vegetation coverage has a significant impact on the dune morphology, which leads to the dune fixation and pie shaped dune morphology. (4) The dune migration rate is also affected by wind regime, surface salinization and sand-fixing measures on both sides of roads.

Key words: dune migration, dune morphology, vegetation, Mu Us Sandy Land

中图分类号:

P931.3

许明静, 吕萍, 肖南, 杨军怀, 刘铮瑶, 冯淼彦, 梁准. 毛乌素沙地西北部植被覆盖对沙丘移动的影响[J]. 中国沙漠, 2020, 40(4): 71-80.

Mingjing Xu, Lü Ping, Nan Xiao, Junhuai Yang, Zhengyao Liu, Miaoyan Feng, Zhun Liang. Effect of vegetation cover on dune migration in northwest Mu Us Sandy Land[J]. Journal of Desert Research, 2020, 40(4): 71-80.

图/表 16

参考文献 34

1	吴正.中国沙漠及其治理[M].北京:科学出版社,2009.
2	王立新,刘华民,杨劼,等.毛乌素沙地气候变化及其对植被覆盖的影响[J].自然资源学报,2010,25(12):2030-2039.
3	韩雪莹,杨光,秦富仓,等.毛乌素沙地近30年沙漠化土地时空动态演变格局[J].水土保持研究,2019,26(5):144-150.
4	李晓岚.毛乌素沙地沙漠化逆转过程及成因分析[D].西安:陕西师范大学,2017.
5	曹艳萍,庞营军,贾晓红.2001-2016年毛乌素沙地植被的生长状况[J].水土保持通报,2019,39(2):29-37.
6	闫峰,吴波,王艳姣.2000-2011年毛乌素沙地植被生长状况时空变化特征[J].地理科学,2013,33(5):602-608.
7	Hunter R E,Richmond B M,Alpha T R.Storm-controlled oblique dunes of the Oregon coast[J].Geological Society of America Bulletin,1983,94(12):1450-1465.
8	吴晓旭,邹学勇,王仁德,等.毛乌素沙地不同下垫面的风沙运动特征[J].中国沙漠,2011,31(4):828-835.
9	黄富祥,牛海山,王明星,等.毛乌素沙地植被覆盖率与风蚀输沙率定量关系[J].地理学报,2001(6):700-710.
10	Wolfe S A,Nickling W G.The protective role of sparse vegetation in wind erosion[J].Progress in Physical Geography,1993,17(1):50-68.
11	王静璞,刘连友,沈玲玲.基于Google Earth的毛乌素沙地新月形沙丘移动规律研究[J].遥感技术与应用,2013,28(6):1094-1100.
12	王静璞,王光镇,韩柳,等.毛乌素沙地不同固沙措施下沙丘的移动特征[J].甘肃农业大学学报,2017,52(2):54-60.
13	北京大学地理系.毛乌素沙地自然条件及其改良利用[M].北京:科学出版社,1983.
14	肖南,董治宝,南维鸽,等.1957—2014年库布齐沙漠地面风场特征[J].中国沙漠,2018,38(3):628-636.
15	Fryberger S G.Dunes forms and wind regime[M]//Mckee E D.A Study of Global Sand Seas.Washington,USA:US Government Printing Office,1979.
16	庞营军,吴波,贾晓红,等.毛乌素沙地风况及输沙势特征[J].中国沙漠,2019,39(1):62-67.
17	张正偲,董治宝.黑河流域中游沙漠风能环境与风沙地貌[J].中国沙漠,2014,34(2):332-341.
18	Yang J,Dong Z,Liu Z,et al.Migration of barchan dunes in the western Quruq Desert,northwestern China[J].Earth Surface Processes and Landforms,2019,44(10):2016-2029.
19	Zhang Z,Dong Z,Hu G,et al.Migration and morphology of asymmetric barchans in the central Hexi Corridor of Northwest China[J].Geosciences,2018,8(6):204.
20	杨军怀,董治宝,刘铮瑶,等.库鲁克沙漠风沙地貌与沙丘移动[J].中国沙漠,2019,39(4):1-8.
21	朱震达,郭恒文,吴功成.塔克拉玛干沙漠西南地区绿洲附近沙丘移动的研究[J].地理学报,1964(1):35-50.
22	Bagnold R A.The Physics of Blown Sand and Desert Dunes[M].London,UK:Methuen,1941.
23	Sharp L P,Long J T.Barchan-dune movement in Imperial Valley,California[J].Geological Society of America Bulletin,1964(2):149-156.
24	Gay S P.Observations regarding the movement of barchan sand dunes in the Nazca to Tanaca area of southern Peru[J].Geomorphology,1999,27(3):279-293.
25	董治宝,陈广庭,颜长珍,等.塔里木沙漠石油公路沿线沙丘移动规律[J].中国沙漠,1998,18(4):34-39.
26	Finkel,Herman J.The barchans of Southern Peru[J].Journal of Geology,1959,67(6):614-647.
27	Hesp P A,K.Width Hastings,height and slope relationships and aerodynamic maintenance of barchans[J].Geomorphology,1998(2):193-204.
28	Dong Z,Wang X,Chen G.Monitoring sand dune advance in the Taklimakan Desert[J].Geomorphology,2000,35(3):219-231.
29	Hack J T.Dunes of the western Navajo Country[J].Geographical Review,1941,31(2):240-263.
30	Lu P,Dong Z,Rozier O.The combined effect of sediment availability and wind regime on the morphology of aeolian sand dunes[J].Journal of Geophysical Research-Earth Surface,2018,123(11):2878-2886.
31	张晓燕,高永,王淮亮,等.毛乌素盐渍化沙地不同亚环境土壤差异性浅析[J].内蒙古林业科技,2010,36(4):5-7.
32	Zuo X,Zhao H,Zhao X,et al.Plant distribution at the mobile dune scale and its relevance to soil properties and topographic features[J].Environmental Geology,2008,54(5):1111-1120.
33	刘艳军,刘明义,修竹奇,等.新发流动沙丘治理措施研究及效益分析[J].中国水土保持,1995(8):10-11.
34	秦伟,段广东,裴志永.毛乌素沙地穿沙公路路域沙柳防护带平茬复壮技术[J].内蒙古大学学报(自然科学版),2019,50(3):294-301.

沙丘类型	移动参数	北翼	南翼	背风坡底部	迎风坡底部	沙丘顶部
裸露沙丘	距离/m	52±19	58±18	67±8	70±15	73±9
裸露沙丘	方向/（°）	136±20	113±10	123±11	120±19	122±11
植被覆盖沙丘	距离/m	27±17	34±18	39±21	32±18	46±22
植被覆盖沙丘	方向/（°）	150±41	117±67	132±20	134±80	132±21

沙丘类型	移动参数	北翼	南翼	背风坡底部	迎风坡底部	沙丘顶部
裸露沙丘	距离/m	52±19	58±18	67±8	70±15	73±9
裸露沙丘	方向/（°）	136±20	113±10	123±11	120±19	122±11
植被覆盖沙丘	距离/m	27±17	34±18	39±21	32±18	46±22
植被覆盖沙丘	方向/（°）	150±41	117±67	132±20	134±80	132±21

研究区	沙丘数量	移动速度/（m·a^-1）	移动方向/（°）
西北部	39	0.38~6.05/3.44	100~210.3/122.5
东北部	5	1.59~5.4/2.79	96.4~120.8/109.3
西南部	5	0.22~2.58/1.54	22.6~174.5/117.2

研究区	沙丘数量	移动速度/（m·a^-1）	移动方向/（°）
西北部	39	0.38~6.05/3.44	100~210.3/122.5
东北部	5	1.59~5.4/2.79	96.4~120.8/109.3
西南部	5	0.22~2.58/1.54	22.6~174.5/117.2

研究区	沙丘数量	移动速度/（m·a^-1）	移动方向/（°）
上风向	6	2.50~5.54/4.24	109.3~143.5/122.8
下风向	14	0.39~5.10/3.38	109.8~210.3/126.7
交叉处	4	1.02~3.95/2.15	101.9~125.9/114.6