基于水工试验探究挺水植物群落对水流结构的影响

Exploring Rigid Vegetation Community’s Influence on the Flow Structure Based on the Hydraulic Experiment

摘要: 在植物群落之中，因为挺水植物与水流之间的关系最为密切，且缓流和净水效果最为突出，常常作为湿地植被修复的首选材料。本文选择芦苇作为研究区优势挺水植物物种，基于室内水工试验确定了不同植株密度的缓流效果。结果表明：① 对于不同植株密度条件下的沿程水位变化，由于存在植被阻力的影响使得群落段前的水位雍高，而在进入植株群落时，由于植株阻力面积的减小使得水位逐渐降低；② 观测不同植被植株密度下各个横纵断面流速分布发现，当植株密度为108株/m2时的植株缓流效果最好；③ 比较不同植被植株密度下各个测点垂向流速分布，发现不同植株密度下各个测点的垂向流速规律相似。研究结果为湿地修复中的植物群落构建提供数据支撑。

Abstract: Emergent plants are often used as the preferred materials for wetland vegetation restoration, because they have the closest relationship with water flow and have the most prominent effect of slow flow and water purification. In this study, Phragmites australis was selected as the dominant emergent plant species in the study area, and the slow-flow effects of different plant densities were determined based on laboratory hydraulic tests. The results were as follows: 1) For the water level change along the path under different plant densities, the water level in front of the community segment was high due to the influence of vegetation resistance, but when entering the community, the water level gradually decreased due to the decrease of plant resistance area. 2) It was found that the slow flow effect was the best when the plant density was 108 plants/m2. 3) Comparing the vertical velocity distribution of each measuring point under different plant densities, it was found that the vertical velocity distribution of each measuring point under different plant densities was similar. The results provide data support for general lake wetland restoration.