Turbulence regime near the forest floor of a mixed broad leaved/Korean pine forest in Changbai Mountains

Abstract

The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (128°28’E and 42°24’N, Jilin Province, P.R. China) in August 2001. The basic characteristics of turbulence, such as turbulence intensity, atmospheric stability, time scales, and convection state, near the forest floor were analyzed. It is concluded that the airflow near forest floor is characterized by high intermittence and asymmetry, and the active and upward movement takes the leading position. Near forest floor, the vertical turbulence is retained and its time scale and length scale are much less than that ofu, v components. The eddy near forest floor shows a flat structure and look like a ‘Disk’. Buoyancy plays a leading role in the generation and maintenance of local turbulence.

Keywords

Forest floor / Velocity statistics / Atmospheric stability / Convection states / S718.51 / A

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