Migration of barchan dunes and factors that influence migration in the Sanlongsha dune field of the northern Kumtagh Sand Sea, China

Zhuanling Yang, Guangqiang Qian, Zhibao Dong, Min Tian , Junfeng Lu

Geomorphology 378 (2021) 107615

Abstract

The Sanlongsha dune field, on the northern edge of China's Kumtagh Sand Sea, is a large area with strong winds, causing rapid dune migration and evolution of dune morphology. By combining remote sensing images with field monitoring, we analyzed seasonal and annual migration of the barchan dunes and the factors that influence this migration. Dunes moved fastest in late spring and summer, and slowest in winter and early spring. The annual migration rates ranged between 7 and 95.2 m/yr, and averaged 35.6 m/yr. The migration directions ranged between 186.6° and 210.8°, and averaged 200.8°. Based on the influence of wind intensity and sand dune size, we found: (1) There is a robust linear relationship between the wind intensity (RDP) and dune migration; (2) In the absence of barchan volume, the basal area as indicators of dune scale can better measure the relationship between dune size and dune migration; (3) Barchan migration distance can be predicted based on the basal area covered by the dune, the resultant drift potential during the prediction period, and the regional annual average resultant drift potential (Di = (RDPi/ RDPmean) × α BAβ ). The migration of barchan dunes is also affected by the dune shape, dune density (dune number per unit area), properties of the underlying surface, and topography. This research enhances our understanding of the dynamic mechanisms of sand dune evolution and migration, and provides theoretical guidance for windbreak and sand fixation projects and dynamic monitoring of desertification.

文章链接：https://www.sciencedirect.com/science/article/pii/S0169555X21000246