3 . a three - dimensional - acoustic doppler velocimeter has been used to measure the velocity and turbulence in a compound channel with vegetated and unvegetated flood - plains . particulary in the interface region between main channel and floodplain . the distribution in three coordinate directions of velocity and turbulence intensities and the renolds stresses are presented . the momentum transfer at the main channel flood - plain interface can be described as an apparent shear stress which can be quantified as a function of the local turbulence at the interface 采用adv对滩地种树前后滩槽交界区域的流速场进行了量测。分析了滩槽交界区域的垂线流速、紊动强度和雷诺应力的变化。将滩槽交界的动量传递描述为一表观应力,这个表观应力可以看作是交界面处的脉动函数并将其定量化。