嫩江干流防浪林消浪影响因素分析

Influencing factors analysis of wave dissipation of the wavebreak forest in mainstream of Nenjiang River

为研究嫩江干流防浪林影响因素对消浪效果的影响,合理设计防浪林优化布局,以东阳堤防为例,利用消浪性能计算公式,选取防浪林排列方式、行株距、树干半径、树冠半径、宽度、刚度作为影响因素,研究其对消浪效果的影响,并进行定量计算和理论分析。结果表明:种植棵数相同时,等边三角形排列方式的消浪效果最好;在不影响泄洪的前提下,防浪林的树干半径、树冠半径、宽度越大或行株距越小时,消浪作用越强;相同宽度下,刚性植物的消浪效果比柔性植物好,且消浪时间更持久;东阳堤防适合营造以刚性植物为主的防浪林,行株距为1.5~2 m,以宽度30~50 m为宜,刚柔混合,且当柔性植物高度大于刚性植物树冠最低处时,消浪效果更好。

In order to study the effect of influencing factors on the wave dissipation and figure out the optimized layout of wavebreak forest in the Nenjiang River mainstream,influencing factors including the arrangement mode,row spacing,stem radius,crown radius,width and rigidity were identified in this study. Then,the quantitative calculation and theoretical analysis based on the calculation formulas of wave dissipation performance were conducted for the Dongyang dike. The results indicate that the equilateral triangle is the best for the wave dissipation under the same trees; in the premise of not affecting the flood discharge,the dissipation effect is better when the forest stem radius,crown radius,and width is larger or the row spacing is smaller; the effect and duration of rigid vegetation is better than the flexible vegetation under a same width; a forest mainly consisting of the rigid vegetation and mixing with the flexible vegetation should be the optimized plan for the Dongyang dike,while the proper row spacing and width are 1.5-2 m and 30-50 m,respectively. Besides,the flexible vegetation should be higher than the lowest top of rigid vegetation to achieve a better performance.