Morphological evolution and migration characteristics of a climbing dune in Mainling Great Valley section of Yarlung Zangbo River
The Yarlung Zangbo River basin has the ideal conditions for aeolian sand deposition,such as sand source,wind power and accumulation site,and aeolian geomorphology are widely distributed in the wide valley of the river.Based on high-resolution remote sensing images from 1970 to 2022 and meteorological data,this study analyzed the morphological evolution and migration characteristics of typical climbing dune in Mainling Great Valley section of Yarlung Zangbo River.The results showed that:(1)From 1970 to 2010,the overall scale of climbing dune in Maicun Village increased significantly,and then remained relatively stable.From 1970 to now,the surface sand ridges of climbing dunes are more and more densely distributed,and the intersection is more and more complicated.For the climbing dune as a whole,there is little correlation between the morphologi-cal parameters,but there is a good correlation between most of the morphological parameters of the surface sand ridges.(2)The prevailing wind direction in Mainling Counrty was N and NNE,while the sand-driving wind di-rection is SW and SSW.The resultant drift direction is 53.87°,and the region has experienced a low wind energy environment(DP=28.18 VU)and moderate wind direction variability(RDP/DP=0.72)over the years.(3)From 2010 to 2022,the sueface sand ridges of climbing dunes moved 15.71 m towards the NNE.The sand ridges mi-gration rate is 0.23-26.79 m·a1,and the average migration rate is 2.57 m·a1.The low wind energy environment in the study area leads to slow sand ridges movement.Additionally,influenced by topography,near-surface air currents and large-scale wind conditions jointly govern the movement of the sand ridges,resulting in a discrepan-cy between their actual movement direction and the resultant drift direction.Terrain,wind conditions,vegeta-tion,precipitation and the characteristics of the dunes themselves combine to create special climbing dune,mak-ing it a unique and eye-catching aeolian geomorphology landscape.
climbing dunedune morphologydune migrationdynamic changeYarlung Zangbo River
NETL
NSTL
万方数据
