塔克拉玛干沙漠腹地风蚀起沙观测试验  

The Study on Observation Experiment of Wind Erosion over the Hinterland of Taklimakan Desert

作　　者：杨兴华[1,2] 何清[1] 丁国锋 霍文[1,2] 

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002 [2]塔克拉玛干沙漠大气环境观测试验站,新疆塔中841000 [3]巴音布鲁克气象站,新疆和静841314

出　　处：《沙漠与绿洲气象》2012年第5期67-72,共6页Desert and Oasis Meteorology

基　　金：中国沙漠气象科学研究基金(Sqj2010014);国家自然科学基金项目(41175017;40975097);公益性气象行业专项(GYHY201006012)

摘　　要：利用美国Sensit公司生产的H11-LIN型风蚀传感器及贴地层风速梯度探测仪,对塔克拉玛干沙漠腹地塔中地区一次风蚀起沙过程进行了监测。结果表明:(1)风蚀起沙与微气象是一个互相影响互相制约的变化过程;(2)在此次观测试验过程中,观测到的最小起沙风速为6.0 m/s左右,同时发现起沙风速是一个变化的值,随着时间的延续呈现逐步增大的趋势,最小的起沙风速出现在风蚀开始发生的时候;(3)近地表风速廓线受沙粒运动影响明显,随着起沙量的增加,风速随高度变化的幅度增大,此时的风速廓线已不再遵循对数分布规律;(4)利用风蚀传感器测得塔中地区沙粒的临界起动摩擦速度为0.25 m/s,该值与经验公式估算的0.24 m/s非常接近,表明风蚀传感器在塔中地区具有较好的适用性;夏季塔中地区地表土壤湿度对风蚀起沙的阻碍作用可以忽略不计。The goal of this study was to obtain a detailed account of wind erosion processes within a single desert field during a dust storm in the hinterland of Taklimakan Desert. Erosion activity was monitored by a Sensit Hl l-LIN saltation sensor that responsed to the impact of sakating grains and provided a way for detecting the threshold of soil movement, and wind speed, temperature, relative humidity were monitored by gradient anemometer for near-surface layer. The results indicated that dust emission by wind erosion and micro-meteorology were mutually affected and limited, at the beginning of the storm the threshold was around 6.0m/s and as the storm progressed the threshold appeared to slowly shift upward with time, suggesting a surface that was becoming increasingly un- erodible. Wind profiles of near-surface layer didn＇t follow the logarithmic distribution, which were significantly affected by sand movements. With the increase of dust emission, wind speed could change dramatically with the increase of height. The threshold friction velocity at Tazhong, 0.25m/s, obtained by Sensit Hll-LIN saltation sensor was very close to the empirical formula value which was, 0.24m/s, suggesting that the Sensit saltation sensor had good applicability in Tazhong region. At the same time, we found that surface soil moisture was no hindering effect on dust emission by wind erosion in summer in Tazhong region.

关 键 词：风蚀 临界摩擦速度 观测试验 塔克拉玛干沙漠 

分 类 号：P445.4[天文地球—大气科学及气象学]