集沙仪开发研究现状、问题及突破点

Current situation,problems and breakthroughs of development and research of sand sampler

输沙(尘)量观测是沙漠化监测、沙尘暴和风沙流研究以及土地风蚀沙化研究的主要内容之一,也是干旱沙漠化地区生态环境观测研究的重要手段之一。集沙仪是其监测必不可少的重要工具之一。目前,开发研制的集沙仪不少,但至今没有统一的观测标准和准确有效的观测仪器。国外用光学颗粒流传感器和等动力方法检验集沙仪的集沙效率,结果表明,集沙仪的集沙效率低于70%。中国多采用风洞测验集沙仪的集沙效率,检验结果为72%~89%。集沙仪开发的难点是难以使得集沙仪管内气流速度等于外界风速,突破点是研制出管内气流流速等于外界风速的集沙仪。主动式集沙仪可解决这一问题。然而,由于需要动力等原因,而未真正进入应用。需要制订统一的观测标准,提高集沙仪开发研制质量和观测质量。这样,才能揭示沙尘暴、风沙流的真实情况,也便于纵向和横向对比分析,有效推进沙漠化和沙尘暴研究的进程。

The observation of sand transportation flux is one of the main tasks in desertification monitoring,the research on sandstorm,aeolian sand flux and wind erosion. It is also one of the measures for eco-environment monitoring in arid desertified lands,with sand sampler being one of the main instruments. At present,there are many kinds of sand samplers. However,there are no observational standards and instruments for precise observation. In abroad,the collecting efficiency of sand samplers,as tested by the optical particle flow sensor and the isokinetic method,was below 70%. In China,the sand collecting efficiency of sand sampler was tested in the wind tunnel,and the collecting efficiency was 72%-89%. The bottleneck of developing sand sampler is how to make the velocity of the air flow in the sand sampler be equal to that in the field. The breakthrough is to invent sand sampler with the flow velocity inside being equal to that in the field. The active sand sampler is able to solve this problem. However,this kind of sand sampler is not yet applied due to power problems. It is needed to formulate a unified observation standard to improve the precise observation of sand samplers. Such an improvement will facilitate the examination of the real situation of sandstorm and aeolian sand flow,the comparison and analyzation of vertical and horizontal sand flow,and the promotion of research on desertification and sandstorm.