ISSN 1002-1027　　CN 11-2952/G2

### Determination of Aerodynamic Parameters of Changbai Mountain Forest

LIU Heping1, LIU Shuhua1, ZHU Tingyao2, JIN Changjie2, KONG Fanzhi2, GUAN Dexin2

1. 1Department of Geophysics, Peking University, Beijing, 100871; 2Institute of Applied Ecology, Academia Sinia, Shengyang, 110015
• Received:1996-09-04 Online:1997-07-20 Published:1997-07-20

Abstract: The aerodynamic roughnees length Z0, the zero-plane displacement d, the momentum drag coefficient CD, water and heat drag coefficient CH are calculated by using turbulence data and wind, temperature profile data observed in Changbai Mountain forest. The causes of the error in the method of calculating d and Z0 are also discussed. The method based on the mass conservation principle is a practical one to calculate the aerodynamic roughness length and zero-plane displacement over tall vegetations. In Changbai Mountain forest, the roughness length Z0 is about 1.6+-0.25m and the zero-plane displacement d is about 19.5+-1.38m. Drag coefficients CD and CH have a good relation with stability under unstable condition, and the average values of CD and CH are 6.6×10-3 and 6.4×10-31 in the neutral atmosphere, respectively.