Abstract: Wind speed is measuied in and above sand-holding forest and above fixed dune at Zhanggutai in 1987 and 1988.The measuied wind speed profiles are employed to evaluate theaerodynamic characteristics and their relations with wind speed for sand-holdirf forest.Thezero plane displacement D,roughness length Z₀ and plant drag coefficient C_d are estimatedas 7.71m,0.93m and 0.13m respectively for the sand-holding forest with an average height of 9.2m at moderate windiness.These characteristic values increase with increasing windspeed.Above canopy,turbulent parameter Ka increases and aero dynamic resistance ra decreases compared with those above fixed dune.

Key words: archaea, crenarchaeota, soil profile, fertilization, real-time PCR