Study on Wind-blown Sand Characteristics at Different Directions near the Surface in the Frontier of an Oasis-desert Ecotone in Qira County,Xinjiang

Aeolian sand transport is serious in many arid regions in the world,and it is considered to be as a significant part of global biogeochemical cycles.Furthermore,wind-blown sand brings often disasters.Therefore,widespread attention has been paid to the significance of aeolian sand transport in many fields,such as geomorphology,climatology,meteorology,ecology and environmental science.Wind-blown sand direction is a base for both studying the formation and evolution of aeolian geomorphology and carrying out the sand damage control measures.In this study,a statistical analysis on wind-blown sand direction in an oasis-desert ecotone in Qira County,located in the south marginal zone of the Tarim Basin,was carried out during the period from 2010 to 2011.Some preliminary conclusions are as follows:(1) In the study area,the wind directions of sand-driving wind are mainly W and WNW,and the change of wind direction is comparatively simple;(2) In the study area,the wind directions at which the values of sediment discharge are high are dominated by NW,WNW,W,SW and WSW,and the occurring frequency is as high as 68.3%.An aeolian sediment discharge of 96 kg passing through a height extent of 0-40 cm and 1-cm width occurred.The annual resultant wind-blown sand amount is 45.9 kg,and the resultant wind-blown sand direction is 102.5°;(3) In the study area,the wind-blown sand potential and resultant wind-blown sand potential are 43.2 VU and 31.04 VU respectively.There is a considerable difference between the direction of wind-blown sand potential and the measured sediment discharge.It is recognized that wind-blown sand is a complex process,and various factors affecting wind-blow sand,such as wind speed,wind direction and underlying surface,should be comprehensively considered and researched.