沙漠是沙尘物质的重要源区,沙漠近地层沙尘水平通量的测量与研究是认识沙尘输送过程、评估风沙活动强度的基础.集沙仪是测量沙尘水平通量的最重要手段之一,被广泛应用于各种观测试验中.集沙效率是集沙仪最重要的参数,是校正沙尘水平通量测量数据的依据.选择塔克拉玛干沙漠腹地塔中地区的典型平沙面为观测点,利用全自动高精度集沙仪,H-11B型Sensit风蚀传感器、10 m气象塔,于2010.7-2010.8月开展了野外观测试验,基于观测数据对全自动集沙仪的集沙效率、近地层沙尘水平通量进行了分析研究.结果表明:相同时段内,集沙总量与Sensit风蚀传感器所记录的跃移颗粒数具有较好的线性关系,R2值平均为0.6053;全自动集沙仪在5 cm高度上的平均集沙效率为94.3%;观测期间,不同沙尘天气过程的沙尘输送量存在显著差异,通过宽2 cm×高5 cm截面的最大沙尘水平通量为190.335 kg,最小为1.2 kg;5 cm高度上的跃移输沙率总体上随着风速的增加而增大,但其中有部分天气时段输沙率随风速的变化不一致,而此情况下对应时段的地表温度明显更大.%Aeolian sand transport caused by soil wind erosion is a serious problem in many arid regions in the world, and it is considered to be the significant part of global biogeochemical cycles. The dust produced by aeolian sand transport can affect the atmospheric radiation balance, climate, the environment, air quality, and human health. Therefore, widespread attention has been attracted to the significance of aeolian sand transport for geomorphology, climatology, meteorology, ecology and environmental science. Sand sampler is an important instrument to measure the quantity of aeolian sand caused by wind erosion, and there were many sand samplers designed and used in wind tunnel and field experiments for measuring aeolian sand. Sampling efficiency is an important parameter for correcting the quantity of aeolian sand collected by sand sampler, its value depends on the structures of sand sampler, wind speed during measurement process, sand particle size and measuring time. The sand-dust horizontal flux is an important parameter for the study on aeolian sand transport, as well as an important foundation. The research on sand-dust horizontal flux can enhance our understanding of soil wind erosion, aeolian sand transport and wind sand disasters. The Taklimakan Desert is the second largest shifting sand desert in the world, with about 85% of its environment made up of shifting sand dunes, and it is known to be an important dust source area that contributes to the high incidence of dusty weather in China. There is an annual average of more than 100 days of dusty weather in the desert, and in some stations this figure can be over 200. It is a huge testing platform for field experiment of aeolian sand transport.In this study, a field experiment was developed to measure the data of aeolian transport and microclimate during different dust events with a auto sand sampler, a piezoelectric saltation sensor (Sensit, H11B) and a 10 m high meteorological tower in Tazhong, the hinterland of the Taklimakan Desert from July to August in 2010. Then the sampling efficiency of auto sand sampler and horizontal dust flux of near surface were analyzed based on observed data. The results showed that: There was a good linear relationship between the amount of sediment and total saltation particle numbers, and the average value ofR2 was 0.6053. The average sampling efficiency of atuo sand sampler was 94.3% at 5 cm high. The horizontal dust flux of different dust events that passed through a section of 100 cm in width and 200 cm in height was calculated with formulaQ=256 m, the maximum of one dust event was about 190.335 kg, and the minimum was 1.2 kg. Overall, the sand transport rate increased with wind speed. However, the changes of sand transport rate did not quite fit in with wind speed during some dust events, and in this case the corresponding surface temperature was significantly higher. The experimental data obtained can provide theoretical basis for regional sand control and enacting effective engineering measures.
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