An estimated 100 million people inhabit coastal areas at risk from flooding and erosion due to climate change. Seagrass meadows, like other coastal ecosystems, attenuate waves. Due to inconsistencies in how wave attenuation is measured results cannot be directly compared. We synthesised data from laboratory and field experiments of seagrass-wave attenuation by converting measurements to drag coefficients (C_D). Drag coefficients varied from 0.02–5.12 with $\overline{C_D}$ = 0.74 for studies conducted in turbulent flow in non-storm conditions. A statistical model suggested that seagrass species affects C_D although the exact mechanism remains unclear. A wave model using the estimated $\overline{C_D}$ as an input parameter demonstrated that wave attenuation increased with meadow length, shoot density, shoot width and canopy height. Findings can be used to estimate wave attenuation by seagrass, in any given set of conditions.

估计有1亿人居住在沿海地区，这些地区因气候变化而遭受洪水和侵蚀的危险。像其他沿海生态系统一样，海草草甸会减弱海浪。由于测量波衰减的方法不一致，因此无法直接比较结果。通过将测量值转换为阻力系数（C _D），我们综合了海草波衰减实验室和野外实验的数据。阻力系数在0.02–5.12之间变化，$\overline{C_d}$= 0.74（对于非暴风雨条件下在湍流中进行的研究）。统计模型表明，海藻种类影响C _D，尽管其确切机制尚不清楚。使用估计的波浪模型$\overline{C_d}$作为输入参数表明，波衰减随草地长度，枝条密度，枝条宽度和冠层高度增加而增加。在任何给定的条件下，这些发现都可以用来估计海草造成的波衰减。