Qu Jianjun introduced that Mingsha Shandong starts from Mogao Grottoes and reaches Danghekou in the west. It stretches for about 40 kilometers from east to west, and about 20 kilometers from north to south. "The sand here can sing?" He explained that Mingsha, also known as ringing sand, whistling sand or musical sand, is often distributed in deserts and beaches. The desert is the rarest one and is considered a kind of magic. Natural phenomenon, and therefore become an important tourist resource. However, the famous Mingsha Mountains in my country, including the Mingsha Mountains in Dunhuang City, Gansu Province, have successively lost their vocal function. After years of research, Qu Jianjun discovered that the surface of natural sand grains of Mingsha Mountain in Dunhuang City are porous (pit)-like structures formed by wind erosion, water erosion and other factors, forming a resonance cavity. With the help of external force, they rub and collide with each other during the movement. The extremely weak vibration sound is amplified by the resonance of a large number of surface cavities, so that the human ear can receive the sound spectrum of the moving sand particles. However, environmental pollution and the increase of human activities have caused the sand grains of Mingsha Mountain in Dunhuang to wear out, which in turn produces dust and other impurities. When these impurities invade the pores on the surface of the sand grains, due to the damping effect they produce, the resonance mechanism of the sand is lost and becomes "dumb sand". His research result won the second prize of the 8th China Innovation and Entrepreneurship Competition Sand Industry Competition in 2019. Qu Jianjun told reporters that in the 1990s, due to the increase of human activities and excessive foot-sliding, the ecological protection of Mingsha Mountain was difficult, and part of Mingsha also gradually lost its sound mechanism. In recent years, the local government has initiated the Mingsha Mountain ban protection project, delineated desertification closed areas, and carried out banned protection and vegetation conservation projects, which to a certain extent helped the recovery of some sandy hills in the Mingsha Mountain in Dunhuang City, and the formation of "tweets" Rare Mingsha group. "After years of scientific protection, part of the sand in Mingsha Mountain in Dunhuang City has been washed, and the surface of the sand has been purified. The sand can be restored to the previous'tweet' after being stepped on." Qu Jianjun suggested that it should be started as soon as possible. Scientific investigation of resources, through the investigation and evaluation of Dunhuang Mingsha resources, accurately locate Mingsha dunes, protect this magical natural phenomenon, and provide scientific basis for the protection and rational development and utilization of Dunhuang Mingsha tourism resources.
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