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为了解含植被水流运动规律,以柔性植物苦草为对象,在室内水槽中开展了苦草斑块对水流时均运动特征影响的试验,观测分析了不同水流(断面平均流速分别为3、5、10cm/s)和不同植株密度(172、86、43、0株/m2)条件下含苦草水流的流速分布结构。结果表明,植被斑块对水平流速分布有影响,在斑块尾部边缘有涡的产生;由于植被的阻流作用,使得植被斑块内部流速沿程减小,斑块外围流速沿程增大;垂线流速呈S型,可划分为底边界层区、冠层次级最大流速区、冠顶过渡区及冠层上部对数流速分布区。植株密度对冠层次级最大流速区影响最为显著,密度越大,流速削减越迅速,逆转梯度越大;断面平均流速越大,植被对水流的影响越显著。
In order to understand the regularity of water flow in vegetation, the experiment was conducted to study the effects of bitter grass patches on the average moving characteristics of water flow in indoor flume. The effects of different water currents , 10 cm / s) and different plant densities (172, 86, 43, 0 plants / m2). The results showed that the vegetation patch had an influence on the horizontal flow velocity distribution and the eddy at the tail edge of the patch. Due to the obstruction of the vegetation, the flow velocity inside the vegetation patch decreased and the flow velocity along the periphery of the patch increased. Vertical flow rate was S-type, can be divided into the bottom boundary zone, the maximum canopy sub-flow area, the crown transition zone and the upper logarithmic velocity distribution. Plant density had the most significant effect on the maximum canopy flow velocity. The greater the density, the faster the flow rate reduction and the larger the reverse gradient. The greater the average cross-section flow rate, the more significant the impact of vegetation on water flow.