| The desert aeolian geomorphology in Qaidam Basin is an important part of Asian aeolian geomorphology.Its wind dynamic system is influenced by planetary wind system and local circulation,and the regional wind energy environment has a good correspondence with different types and distributions of dunes.However,because the desert in Qaidam Basin is located in the special physical and geographical environment of high and cold plateau,the research on the overall aeolian sand geomorphology characteristics and development environment of the desert is not complete at present.The characteristics of wind energy environment of the desert in Qaidam Basin are systematically studied,and the dynamic factors of aeolian sand geomorphology formation are accurately mastered,providing scientific basis and reference for regional aeolian sand geomorphology related research.On the basis of field investigation in the Qaidam Basin,this study used 9 field scientific meteorological stations built in the desert of the Qaidam Basin and high～resolution remote sensing observation of Google Earth to collect basic data of wind regime of meteorological stations,analyze the characteristics of annual wind speed,wind direction and sand transport potential of the desert of the Qaidam Basin,and compare the wind energy environment of regions with different aeolian sand landforms.To explore the influence of different wind energy environments on the development of desert aeolian geomorphology in Qaidam Basin.The main findings are as follows:(1)The wind speed in the desert of Qaidam Basin has obvious spatio-temporal difference.The average annual wind speed and the average sand-driving wind speed have the same spatial distribution trend,decreasing from the northwest to the east,and gradually increasing from the center of the basin to the marginal mountains.The variation trend of annual maximum wind speed is consistent with the variation trend of monthly average wind speed of sand-driving wind,with the maximum appearing in summer and the minimum appearing in winter.From the perspective of different aeolian sand landforms,the frequency of aeolian wind is higher in autumn and lowest in winter,except for the long ridge Yadan landform,the frequency of other aeolian wind landforms is highest in summer and lowest in winter.(2)The main wind direction of the desert in Qaidam Basin is mainly north to east except Fangshan-like Yadan landform,while the main wind direction in other regions is west to north and west to north.The variation range of sand-driving wind direction is small and the wind direction is relatively simple.Except Fangshan-like Yadan landform and houndlike Yadan landform,the main wind direction in other study areas is west to northwest.(3)The Qaidam Basin is a medium wind energy environment.The Yadan landform in the northwest is close to the medium to high wind energy environment.The resultant sediment transport potential gradually decreases from northwest to southeast,and the distribution trend of resultant sediment transport potential is similar to that of the resultant sediment transport potential.The wind direction variability index ranged from 0.70 to 0.98,indicating that the moderate and low variability corresponded to the wide unimodal wind regime and the sharp bimodal wind regime.The direction of resultant sediment transport potential changes from the northwest to the middle to the east of the basin from south to east to east.(4)The development of desert aeolian geomorphology in Qaidam Basin is greatly affected by wind dynamics,and the direction of sand dunes is consistent with the direction of synthetic sand transport potential.The barchan dune mainly develops in low wind energy environment,and the linear dune mainly develops in low and medium wind energy environment,and the symbionic dune develops in medium wind energy environment under the medium wind wind variability and blunt bimodal wind condition.The wind direction variation rate is medium variable and sharp bimodal;In the Qaidam Basin,the main body axis strike of Yadan is NW-SE,WNW-SSE,NW-SE,and the main body axis strike of each shape of Yadan is consistent with the direction of regional sand-driving wind.The archshaped Yadan landform and the whale-shaped Yadan landform are mainly developed in low wind energy environment,and the moderate wind direction variation is blunt and doublepeak wind.The hound-shaped Yadan landform is developed in low wind energy environment and low wind direction variation.Under narrow single-peak wind conditions,the long ridge Yadan landform is mainly developed under high wind energy environment,low wind direction variability and narrow single-peak wind conditions.(5)The wind energy environment,which is relative to the distribution and development of desert dunes in Qaidam Basin in China’s northern desert,follows the existing research law that the higher the wind energy is,the simpler the dune type is.The distribution characteristics of directional ratio are mostly consistent with the existing research law of wind regime in northern desert,and the near-formation wind field characteristics are consistent with the direction of synthetic sediment transport potential. |
