Field Ovservation of Threshold Frictional Velocity on Different Types of Farmland

To quantize the difficulty level of dust production on the surface of different types of farmland,we used the Marticorena threshold frictional velocity pattern to simulate the dust threshold frictional velocity.The results are: the dust threshold frictional velocity of desertification farmland is 7.39cm s⁻¹, after the wheat harvested and the farmland ploughed is 29.05 cm s⁻¹, the turning green period is 46.85 cm s⁻¹, shooting period is 98.93 cm s⁻¹,the uncovered and the establishment period of fruit tree farmland is 26.01 cm s-1 and 139.15 cm s⁻¹ .Result show that, bare desertification farmland can be changed into source of dust release easiest.