Assessing the flow resistance caused by vegetation in rivers is a hot topic in the field of hydraulics and eco-hydrology. Based on mathematical experiments by first-order closure models, new roughness height of vegetation is proposed linked with the three factors that vegetation arrangement concentration, submergence ratio, and the ratio of width to height of vegetation. Besides, new Darcy–Weisbach friction factor is built for vegetated flow. Moreover, both collected and present experimental data are adopted for verification of the roughness height and friction factor. Compared with models from other research groups, results show that the new formulas proposed in this study have high accuracy for predicting vegetation resistance in ecological restoration and water resources management in rivers.

中文翻译：

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河道流中植被粗糙度高度和Darcy-Weisbach摩擦系数的新公式

评估河流植被引起的流阻是水力学和生态水文学领域的热门话题。基于一阶闭合模型数学实验，结合植被排列集中度、淹没率、植被宽高比三个因素，提出了新的植被粗糙度高度。此外，新的达西-魏斯巴赫摩擦系数是针对植被流而建立的。此外，采用收集的和现有的实验数据来验证粗糙度高度和摩擦系数。与其他研究组的模型相比，结果表明，本研究提出的新公式对于河流生态恢复和水资源管理中植被阻力的预测具有较高的准确性。