Preliminary Study on Dust Emission Rate over Arid Steppe Area

The dust particle concentration data measured by Wide Range Particle Spectrometer and the data observed at a 20 m meteorological tower were used to calculate the dust emission rate,friction velocity and threshold friction velocity over Zhurihe area,Inner Mongolia.The result indicated that: ①The value of dust flux was in accordance with the intense of the dust weather.The average dust flux in dust-storm weather and blowing sand weather were 6.0×10-8 kg.m-2.s-1 and 4.14×10-8 kg.m-2.s-1,respectively.②The friction velocity(U*) was almost less than 1 m.s-1.The relationship between dust emission rate and friction velocity was analyzed,when n is 1 or 2,the dust flux had the best linear correlation with U*n in Zhurihe area.③The threshold friction velocity of the observed dust diameter width was calculated—it firstly declined then ascended with diameter increasing.