Study On The Mechanism Of Shelterbelt On The Reduction Sand-dust Storm Near The Ground Surface

Sand-dust storm is a kind of calamitous weather phenomenon ,which means that strong wind draws much sand and dust near the ground surface into the sky, making air very foul and with visibility lower than 1km.In recent years, sand-dust storm has become one of popular problems which many researchers from all over the world try to study .In this paper ,on the basic theories foundation study of summary people of the past, using field observation test with wind tunnel experiment, combining meteorological resources of south and north weather station, we mainly study on the regulation and features of shelterbelt on the reduction sand-dust storm near the ground surface .In the end, the study results indicate:(1)horizontal distribution features of dustfall is that the amount of dustfall increases successively from the edge of shelterbelt to the middle part of shelterbelt, besides ,the amount of dustfall also change with the change of shelterbelt structure in different places in the same net(the front part of the net, the middle part of the net and the back part of the net);(2)vertical distribution features of dustfall: the amount of dustfall decreases with the increase of height, what,s more, the amount of dustfall of 2m height and 5m height is related in the index number; (3)shelterbelt structure influences the amount of dustfall greatly : the optimum degree of lighting of shelterbelt should between 2.4 and 3.4.Therefore in our future designing shelterbelt,we not only should consider its degree of lighting but also should consider its structure, only thus can we attain the best protection result.